Return to Flight Task Group

Final Report 

July 2005 

Final Report

of the 

Return to Flight 

Task Group 

Assessing the Implementation of the 

Columbia Accident Investigation Board 

Return-to-Flight Recommendations 

July 2005 
Final Report of the Return to Flight Task Group 

On the Front Cover 

The STS-114 patch design signifies the return of the Space Shuttle to flight 

and honors the memory of the STS-107 Columbia crew. The blue Shuttle 

rising above Earth’s horizon includes the Columbia constellation of seven 

stars, echoing the STS-107 patch and commemorating the seven members 

of that mission. The crew of STS-114 will carry the memory of their friends 

on Columbia and the legacy of their mission back into Earth orbit. The 

dominant design element of the STS-114 patch is the planet Earth, which 

represents the unity and dedication of the many people whose efforts allow 

the Space Shuttle to safely return to flight. Against the background of the 

Earth at night, the blue orbit represents the International Space Station 

(ISS), with the EVA crewmembers named on the orbit. The red sun on the 

orbit signifies the contributions of the Japanese Space Agency to the 

mission and to the ISS program. The multi-colored Space Shuttle plume 

represents the broad spectrum of challenges for this mission, including 

Orbiter inspection and repair experiments, and bringing supplies to the 

International Space Station. (Courtesy of NASA) 

On the Title Page 

Discovery heads for the International Space Station during the STS-114 

return-to-flight launch on July 26, 2005. 

On the Back Cover 

The seven stars of the Columbia constellation are in memory of the 

crewmembers lost on STS-107. 

Page 2 of 216 
Final Report of the Return to Flight Task Group 

CONTENTS 

INTRODUCTION TO THE RETURN TO FLIGHT TASK GROUP .............................. 5

ORGANIZATION OF THE RTF TG FINAL REPORT ................................................... 9

EXECUTIVE SUMMARY .................................................................................................. 11

1 BACKGROUND .................................................................................................... 21

2 RELATIONSHIPS AMONG THE RECOMMENDATIONS ........................... 23

2.1 THERMAL PROTECTION SYSTEM RISK REDUCTION FRAMEWORK............................. 23

2.2 INTEGRATED VEHICLE ASSESSMENT......................................................................... 25

3 ASSESSMENT OF THE CAIB RECOMMENDATIONS ................................. 29

3.1 CAIB RECOMMENDATION 3.2-1 – EXTERNAL TANK DEBRIS SHEDDING .................. 31

3.2 CAIB RECOMMENDATION 3.3-1 – RCC NON-DESTRUCTIVE INSPECTION ................ 39

3.3 CAIB RECOMMENDATION 3.3-2 – ORBITER HARDENING ......................................... 43

3.4 CAIB RECOMMENDATION 3.4-1 – GROUND-BASED IMAGERY ................................. 49

3.5 CAIB RECOMMENDATION 3.4-2 – HIGH-RESOLUTION IMAGES OF ET...................... 57

3.6 CAIB RECOMMENDATION 3.4-3 – HIGH-RESOLUTION IMAGES OF ORBITER ............ 59

3.7 CAIB RECOMMENDATION 4.2-1 – SOLID ROCKET BOOSTER BOLT CATCHER .......... 63

3.8 CAIB RECOMMENDATION 4.2-3 – TWO-PERSON CLOSEOUT INSPECTIONS............... 67

3.9 CAIB RECOMMENDATION 4.2-5 – KSC FOREIGN OBJECT DEBRIS DEFINITION........ 69

3.10 CAIB RECOMMENDATION 6.2-1 – CONSISTENCY WITH RESOURCES ........................ 73

3.11 CAIB RECOMMENDATION 6.3-1 – MISSION MANAGEMENT TEAM IMPROVEMENTS .. 77

3.12 CAIB RECOMMENDATION 6.3-2 – NIMA MEMORANDUM OF AGREEMENT.............. 83

3.13 CAIB RECOMMENDATION 6.4-1 – TPS INSPECTION AND REPAIR............................. 85

3.14 CAIB RECOMMENDATION 9.1-1 – PLAN FOR ORGANIZATIONAL CHANGE................ 95

3.15 CAIB RECOMMENDATION 10.3-1 – DIGITIZE CLOSEOUT PHOTOS .......................... 107

3.16 RAISING THE BAR ACTION SSP-3 – CONTINGENCY SHUTTLE CREW SUPPORT ....... 111

4 TRANSITION TO THE ASAP ........................................................................... 119

4.1 CONDITIONS FOR TRANSITION ................................................................................ 119

4.2 ITEMS TO BE TRANSITIONED ................................................................................... 121

5 THE RETURN TO FLIGHT TASK GROUP ................................................... 127

5.1 FEDERAL ADVISORY COMMITTEE ACT ................................................................... 127

5.2 PURPOSE AND DUTIES OF THE TASK GROUP ........................................................... 128

5.3 ORGANIZATION OF THE TASK GROUP ..................................................................... 129

5.4 RELATIONSHIP TO THE NASA IMPLEMENTATION PLAN.......................................... 133

5.5 CONDUCT OF THE ASSESSMENT .............................................................................. 134

5.6 ASSESSMENT CLOSURE PROCESS............................................................................ 135

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Final Report of the Return to Flight Task Group 

5.7 SUMMARY OF INTERIM REPORTS............................................................................. 137

6 SUMMARY OF THE RTF TG PLENARY MEETINGS................................ 139

6.1 SUMMARY OF AUGUST 2003 PLENARY.................................................................... 139

6.2 SUMMARY OF SEPTEMBER 2003 PLENARY .............................................................. 140

6.3 SUMMARY OF DECEMBER 2003 PLENARY ............................................................... 140

6.4 SUMMARY OF APRIL 2004 PLENARY ....................................................................... 141

6.5 SUMMARY OF JULY 2004 PLENARY......................................................................... 143

6.6 SUMMARY OF SEPTEMBER 2004 PLENARY .............................................................. 143

6.7 SUMMARY OF DECEMBER 2004 PLENARY ............................................................... 144

6.8 SUMMARY OF FEBRUARY 2005 PLENARY................................................................ 146

6.9 SUMMARY OF THE MARCH 2005 PLENARY.............................................................. 146

6.10 SUMMARY OF THE EARLY JUNE 2005 PLENARY ...................................................... 147

6.11 SUMMARY OF THE LATE JUNE 2005 PLENARY......................................................... 148

APPENDIX A – RETURN TO FLIGHT TASK GROUP CHARTER ......................... 149

CHARTER EXTENSION ........................................................................................................ 151

APPENDIX B – RTF TG MEMBERS ............................................................................. 153

APPENDIX C – RTF TG STAFF..................................................................................... 167

APPENDIX D – RTF TG FACT-FINDING ACTIVITIES............................................ 169

APPENDIX E – ACRONYMS .......................................................................................... 183

ANNEX A – INDIVIDUAL MEMBER OBSERVATIONS ........................................... 187

A.1 OBSERVATIONS BY MAJ. GEN. WILLIAM A. ANDERS .............................................. 187

A.2 OBSERVATIONS BY DR. DAN C. CRIPPEN, DR. CHARLES C. DANIEL,

DR. AMY K. DONAHUE, COL. SUSAN J. HELMS,

MS. SUSAN MORRISEY LIVINGSTONE, DR. ROSEMARY O’LEARY,

AND MR. WILLIAM WEGNER ................................................................................... 188

A.3 OBSERVATIONS BY MR. JOSEPH W. CUZZUPOLI AND MR. RICHARD H. KOHRS ...... 207

A.4 OBSERVATIONS BY DR. CHARLES C. DANIEL.......................................................... 207

A.5 OBSERVATIONS BY MS. SUSAN MORRISEY LIVINGSTONE ....................................... 208

A.6 OBSERVATIONS BY MR. JAMES D. LLOYD, EX-OFFICIO ........................................... 209

A.7 OBSERVATIONS BY LT. GEN. FORREST S. MCCARTNEY .......................................... 210

A.8 OBSERVATIONS BY DR. ROSEMARY O’LEARY ........................................................ 210

A.9 OBSERVATIONS BY MR. SEYMOUR Z. RUBENSTEIN................................................. 213

A.10 OBSERVATIONS BY MR. ROBERT B. SIECK .............................................................. 214

Page 4 of 216 
Final Report of the Return to Flight Task Group 

INTRODUCTION TO THE RETURN TO FLIGHT TASK GROUP 

On February 1, 2003, the Space Shuttle Columbia disintegrated while returning to Earth 

during the STS-107 mission, killing the crew of seven. Within hours, the independent 

Columbia Accident Investigation Board (CAIB) was appointed by the NASA Administrator. 

Determining the most-probable physical cause of the Columbia accident – foam debris from 

the External Tank impacting the reinforced carbon-carbon on the Orbiter wing leading edge – 

was the more-straightforward part of the investigation conducted by the accident board. 

Unlike many accident boards, however, the CAIB elected to delve deeper into the accident 

than simply determining the physical cause. It was obvious to the board very early-on that 

there was an underlying problem with leadership, management, and culture at NASA, and 

specifically within the Space Shuttle Program. Ultimately, the CAIB placed as much weight 

on these causal factors as on the more easily understood and correctable physical cause of the 

accident. 

The CAIB released the first volume of its final report on August 26, 2003, containing 29 

specific recommendations and numerous findings and observations for changes to the vehicle, 

to the Space Shuttle Program, and to NASA in general. Among those recommendations were 

15 that the accident board believed should be implemented prior to returning the Space 

Shuttle to flight. 

On April 14, 2003, then-NASA-Administrator Sean O’Keefe wrote Lt. Gen. Thomas P. 

Stafford, U.S. Air Force (Ret.), requesting that the Stafford Task Force on International Space 

Station Operational Readiness undertake an assessment of NASA’s plans to return the Space 

Shuttle to flight. The Stafford Task Force is a standing body chartered by the NASA Advisory 

Council, an independent advisory group to the NASA Administrator. 

One month later, Lt. Gen. Stafford responded to the Administrator with a plan to activate a 

sub-organization with Col. Richard O. Covey, U.S. Air Force (Ret.), leading the day-to-day 

effort of conducting an independent assessment of the 15 CAIB return-to-flight 

recommendations. As a result, on July 18, 2003, a Return to Flight Task Group (RTF TG, or 

simply, the Task Group) was chartered under the Federal Advisory Committee Act (Public 

Law 92-463, as amended) with Lt. Gen. Stafford and Col. Covey as co-chairs. 

Over the past two years, using expertise from academia, aerospace industry, the federal 

government, and the military, the RTF TG assessed the actions taken by NASA to implement 

the 15 CAIB return-to-flight recommendations plus one additional item the Space Shuttle 

Program assigned to itself as a “raising the bar” action. During this time the Task Group 

conducted fact-finding activities, reviewed documentation, held public meetings, reported the 

status of its assessments to the Space Flight Leadership Council, and released three interim 

reports. The assessments of the Task Group, although based primarily on data provided by the 

Space Shuttle Program, were independent of that program and were intended to provide the 

NASA Administrator an evaluation of the progress NASA made toward meeting the intent of 

the CAIB recommendations. 

The Task Group completed their last assessments on June 27, 2005; this report does not 

contain data released after that date (excepting a few photographs). Although this report is 

being released after the landing of STS-114, pertinent information contained herein was 

briefed to the appropriate NASA officials prior to the launch of STS-114. 

As the Task Group delivers this final report to the NASA Administrator, Congress, and the 

American public, we take this opportunity to emphasize that this report is strictly advisory. 

Only NASA can, and should, make the determination if the vehicle, supporting infrastructure, 

and management organization are sufficiently robust to continue flying. 

Page 5 of 216 
Final Report of the Return to Flight Task Group 

The Signatures on these pages are applicable to the Body and Appendices contained in this Final Report, 

Not to the Individual Member Observations contained in Annex A. 

Co-Chair Co-Chair 

Lt. Gen. Thomas P. Stafford, U. S. Air Force (Ret.) Col. Richard O. Covey, U. S. Air Force (Ret.) 

Col. James C. Adamson, U. S. Army (Ret.) Maj. Gen. William A. Anders, USAF Reserve (Ret.) 

Dr. Walter D. Broadnax, Ph.D. Dr. Kathryn I. Clark, Ph.D. 

Mr. Benjamin A. Cosgrove Dr. Dan L. Crippen, Ph.D. 

Mr. Joseph W. Cuzzupoli Dr. Charles C. Daniel, Ph.D. 

Page 6 of 216 
Final Report of the Return to Flight Task Group 

ine H. Fox ) 

ex-officio 

Dr. Amy K. Donahue, Ph.D. Gen. Ronald R. Fogleman, U. S. Air Force (Ret.) 

Ms. Christ Col. Gary S. Geyer, U. S. Air Force (Ret.

Col. Susan J. Helms, U. S. Air Force Mr. Richard H. Kohrs 

Ms. Susan Morrisey Livingstone Mr. James D. Lloyd 

Lt. Gen. Forrest S. McCartney, U. S. Air Force (Ret.) Dr. Rosemary O’Leary, J.D., Ph.D. 

Dr. Decatur B. Rogers, P.E., Ph.D. Mr. Seymour Z. Rubenstein 

Mr. Robert B. Sieck Mr. Thomas N. Tate 

Dr. Kathryn C. Thornton, Ph.D. Mr. William Wegner 

Page 7 of 216
Final Report of the Return to Flight Task Group 

, as 

of the Vehicle 

of a Space Shuttle 

since the loss of 

on 

y

Discovery

STS-114, rolls out 

Assembly Building at 

the Kennedy Space 

Center on her way to 

Launch Complex 

39B for the first flight 

Columbia

Februar 1, 2003. 

Page 8 of 216
Final Report of the Return to Flight Task Group 

ORGANIZATION OF THE RTF TG FINAL REPORT 

This final report is organized into an executive summary, six numbered sections, various 

appendices, and one annex. 

The Executive Summary provides an overview of the efforts by NASA toward implementing 

the return-to-flight recommendations of the Columbia Accident Investigation Board (CAIB) 

and a summary of the Task Group’s assessments of each. Also included is an assessment of a 

“raising the bar” action that the Space Shuttle Program assigned to itself above and beyond 

the CAIB recommendations. The Executive Summary was delivered to the NASA 

Administrator and posted on the RTF TG website on June 28, 2005; however, the version 

contained herein has been slightly edited without affecting its content. 

Section 1 is a short, general introduction to the Space Shuttle Program and its current place in 

the Agency’s long-term plans. 

Section 2 attempts to show the interrelationships among the various recommendations since, 

in many cases, the implementation and assessment crossed multiple CAIB recommendations. 

This section also contains an assessment from the Task Group’s Integrated Vehicle 

Assessment Sub-Panel that cuts across several recommendations. 

Section 3 is the Task Group’s formal assessment of each of the CAIB return-to-flight 

recommendations, in numerical order. First, the original language of the CAIB 

recommendation is provided, followed by the Task Group’s interpretation of that 

recommendation. Next is any relevant background information that might assist the reader in 

understanding the recommendation. This is followed by an explanation of the steps NASA 

took to implement the recommendation. For the most part, the NASA implementation comes 

from NASA’s Implementation Plan for Space Shuttle Return to Flight and Beyond, using 

whatever edition was current on the date the Task Group deliberated closing their assessment. 

Additional information from the closure packages submitted by NASA, requests for 

information, and fact-finding activities are also included as necessary to ensure an adequate 

description. This is followed by the Task Group’s assessment of the Agency’s progress up to 

the date of the deliberation, and the final status of the assessment. Observations and minority 

views, if any, regarding a particular recommendation follow the assessment. 

Section 4 describes open work the RTF TG will transition to the Aerospace Safety Advisory 

Panel (ASAP) or other appropriate organizations. 

Section 5 introduces the Task Group, its function, the members, and the staff who supported 

it. Also discussed is the organization of the Task Group, a bit of its history and changes in 

personnel, policies, procedures, and processes, and a brief summary of the three interim 

reports issued by the Task Group prior to this final report. 

Section 6 provides a summary of the 11 plenary meetings of the Task Group. This gives a 

brief insight into the progress made along the way to this final report. 

Various appendices contain the charter, short biographies of the members, a list of the staff 

who supported the Task Group, dates of fact-finding activities, and an acronym list. 

Annex A contains a set of observations by individual Task Group members that are provided 

to assist the NASA Administrator in understanding any issues or other items they may have 

observed during the assessments. This section allows members of the Task Group an 

opportunity to make “observations on safety or operational readiness” as allowed by the RTF 

TG charter. 

Page 9 of 216 
Final Report of the Return to Flight Task Group 

lingers at 

Space Shuttle sits 

atop a Mobile 

photo courtesy of 

Scott Andrews) 

Discovery

the foot of Launch 

Complex 39B in the 

evening twilight on 

April 6, 2005. The 

Launcher Platform 

transported on top of 

a CrawlerTransporter. (NASA 

Page 10 of 216
Final Report of the Return to Flight Task Group 

EXECUTIVE SUMMARY 

It has been 29 months since Columbia was lost over East Texas in February 2003. Seven 

months after the accident, the Columbia Accident Investigation Board (CAIB) released the 

first volume of its final report, citing a variety of technical, managerial, and cultural issues 

within NASA and the Space Shuttle Program. To their credit, NASA offered few excuses, 

embraced the report, and set about correcting the deficiencies noted by the accident board. Of 

the 29 recommendations issued by the CAIB, 15 were deemed critical enough that the 

accident board believed they should be implemented prior to returning the Space Shuttle to 

flight. Some of these recommendations were relatively easy, most were straightforward, a few 

bordered on the impossible, and others were largely overcome by events, particularly the 

decision by the President to retire the Space Shuttle by 2010. 

The Return to Flight Task Group (RTF TG, or simply, the Task Group) was chartered by the 

NASA Administrator in July 2003 to provide an independent assessment of the 

implementation of the 15 CAIB return-to-flight recommendations. An important observation 

must be stated up-front: neither the CAIB nor the RTF TG believes that all risk can be 

eliminated from Space Shuttle operations; nor do we believe that the Space Shuttle is 

inherently unsafe. What the CAIB and RTF TG do believe, however, is that NASA and the 

American public need to understand the risks associated with space travel, and that NASA 

must make every reasonable effort to minimize such risk. 

Since the release of the CAIB report, NASA and the Space Shuttle Program expended 

enormous effort and resources toward correcting the causes of the accident and preparing to 

fly again. Relative to the 15 specific recommendations that the CAIB indicated should be 

implemented prior to returning to flight, NASA has met or exceeded most of them – the Task 

Group believes that NASA met the intent of the CAIB for 12 of these recommendations. The 

remaining three recommendations were so challenging that NASA could not comply 

completely with the intent of the CAIB, but conducted extensive study, analyses, and 

hardware modifications that resulted in substantive progress toward making the vehicle safer. 

It must be emphasized, however, that, the inability to fully comply with all of the CAIB 

recommendations does not imply that the Space Shuttle is unsafe. 

Workers in the 

l 

Center watch 

during her 

Launch Contro

Center at the 

Kennedy Space 

Discovery

slow trip to LC-39B. 

Page 11 of 216 
Final Report of the Return to Flight Task Group 

Although the scorecard is impressive, it alone does not tell the complete story. The Task 

Group applauds NASA for its efforts, but urges continued vigilance is required to prevent 

another accident. Spaceflight is a demanding pursuit, and the President, Congress, NASA, and 

the American public must provide the proper resources and environment to ensure it is 

conducted in the safest and most efficient manner possible. 

It is important to reiterate: the NASA Administrator and his staff – not the CAIB or the RTF 

TG – will ultimately determine if the remaining risk is sufficiently low to allow the Space 

Shuttle to continue flying. The Task Group cannot, and will not, make a determination of the 

safety or reliability of the next flight; that is NASA’s responsibility. 

On the hardware side, Solid Rocket Booster Bolt Catcher was redesigned in order to qualify it 

to existing requirements. Numerous changes have been made to reduce debris shedding from 

the External Tank. The ET has been modified to eliminate the bipod ramp foam that was the 

physical cause of the Columbia accident. The procedures for manual application of foam 

insulation have been changed to include greater process control and quality inspection. Much 

has been learned about foam and ice and what causes them to shed from the External Tank 

during ascent. Heaters have been added to areas of the External Tank to impede the formation 

of ice, and various other flaws in the design and manufacture of the tank were discovered and 

corrected along the way. Nevertheless, despite diligent work, it has proven impossible to 

completely eliminate debris shedding from the External Tank. The hard fact of the matter is 

that the External Tank will always shed debris, perhaps even pieces large enough to do critical 

damage to the Orbiter. 

is hoisted 

position in the 

Vehicle Assembly 

Building at the 

mated wi

set of Solid Rocket 

Boosters and an 

External Tank. 

Before a group of 

photographers, 

Discovery

into a vertical 

transfer aisle of the 

Kennedy Space 

Center. After this the 

Orbiter was lifted into 

a High Bay to be 

th a waiting 

Page 12 of 216 
Final Report of the Return to Flight Task Group 

Prior to the Columbia accident, surprisingly little was known about the actual impact 

resistance of the Orbiter Thermal Protection System, especially the Reinforced CarbonCarbon (RCC) that is used on the wing leading edges and nosecap. A great deal of effort – 

using both theoretical analysis and physical testing – has been expended over the past two 

years to quantify the durability and strength of the Orbiter Thermal Protection System, 

particularly its ability to withstand debris impacts. However, because of the limited amount of 

time remaining before the Space Shuttle fleet is retired, NASA has chosen to implement only 

a limited number of improvements to harden the Orbiter to withstand debris strikes. 

It was therefore prudent to develop a capability to repair damage to the Orbiter before entry; a 

similar effort was cancelled in 1980 when it became apparent that it was unlikely to produce 

any meaningful results prior to the first flight of Columbia in 1981. Unfortunately, repairing 

damage to the Orbiter Thermal Protection System again proved to be technically challenging 

almost to the point of impossibility. The Thermal Protection System was not designed to be 

repaired on-orbit, and virtually every approach developed thus far has serious limitations. 

While work will continue, it is likely that only very limited on-orbit repairs will be possible 

for the remaining flights of the Space Shuttle. 

The last resort, if debris does again cripple an Orbiter, is to provide a safe haven capability 

aboard the International Space Station where a Space Shuttle crew can await a rescue vehicle. 

NASA has made good progress in identifying the challenges associated with this concept, and 

the Task Group feels that a workable solution is in hand, although using it will certainly mean 

the end of the Space Shuttle Program, and very possibly the International Space Station 

Program also. Additionally, this capability is only planned for STS-114 and STS-121. 

Along with the changes to the External Tank and Orbiter, NASA has implemented a host of 

improvements to the infrastructure and tools available to the Space Shuttle Program. 

Improved ground-based cameras will track the Space Shuttle during ascent, as will airborne 

cameras mounted on WB-57 aircraft. New cameras and instrumentation have been installed 

on the External Tank, Solid Rocket Boosters, and Orbiter. Agreements to use National assets 

are in place, and instruments on the International Space Station and the newly-installed 

Orbiter Boom Sensor System will inspect the Orbiter for damage. Dozens of new analytical 

models attempt to explain debris shedding, debris transport methods, and potential damage. 

The CAIB went beyond the technical issues that were the physical cause of the Columbia 

accident and cited “management” and “culture” shortcomings as equally culpable. Therefore, 

the accident board made a number of recommendations for changes to how the Agency, 

especially the Space Shuttle Program, functions. 

The Task Group feels that NASA has met the intent of the CAIB management 

recommendations, although all of them remain works in progress. The establishment of an 

Independent Technical Authority within the Chief Engineer’s office moves technical 

requirements out of the direct control of the Space Shuttle Program management chain. This 

provides a check-and-balance when it becomes necessary to approve waivers or deviations to 

a technical requirement, since the Independent Technical Authority is not constrained by 

budget or schedule pressures that may be present within the program. Although initiated prior 

to the release of the CAIB report, the establishment of the NASA Engineering and Safety 

Center (NESC) has created an independent body that provides technical assessments across 

the Agency. A restructured Safety and Mission Assurance (SMA) organization increases the 

independence of SMA personnel. Reorganizing the systems engineering and systems 

integration activities within the Space Shuttle Program clears up several ambiguities that led 

to confused communications between elements. 

The Mission Management Team (MMT), much maligned by the CAIB, has been reconstituted 

and has undergone extensive training, with multiple simulations of alternative scenarios, 

including consideration of the use of the International Space Station as a safe haven for the 

Page 13 of 216 
Final Report of the Return to Flight Task Group 

crew of a damaged Orbiter, and the launch of a rescue mission. Refurbished facilities for the 

MMT provide a more conducive environment for their deliberations during each flight. It 

appears to the Task Group that the changes to the MMT have revitalized this group, but we 

stress that NASA must not allow this capability to atrophy as it had prior to the Columbia 

accident. 

Publicly, NASA has said that the first two return-to-flight missions are “test flights” to assess 

the performance of the modified External Tank and to evaluate repair materials and 

techniques on orbit. In reality, however, the flights are planned as much for servicing the 

International Space Station as for testing. NASA intends to carefully monitor the performance 

and condition of the Space Shuttle during these two flights. For example, the launch rules 

require specific daylight conditions at the Kennedy Space Center and during External Tank 

separation to facilitate detailed imagery of the Orbiter and External Tank. 

Risk acceptance and management are fundamental to leadership in hazardous technical 

activities and are the ultimate responsibility of any leader. Very few human endeavors, 

particularly related to high-energy activities involving advanced technologies, are completely 

free of risk. Space flight in general, and human space flight in particular, is such that it is 

impossible to drive the risk to zero. While the return-to-flight efforts have eliminated or 

minimized many known risks, Space Shuttle missions will always be “accepted risk” 

operations. This requires that the people involved understand, document, and ultimately 

accept the risk associated with that activity. NASA must be vigilant to prevent the 

development of a false sense of security by accepting faulty assumptions, or otherwise 

inappropriate analyses, to justify return to flight and continued Space Shuttle operations. 

As the CAIB opined, “NASA is a federal agency like no other. Its mission is unique, and its 

stunning technological accomplishments, a source of pride and inspiration without equal, 

represent the best in American skill and courage. At times NASA’s efforts have riveted a 

nation, and it is never far from public view and close scrutiny from many quarters.” With this 

in mind, the Task Group believes that NASA must always strive for the highest level of 

accomplishment, to exceed the expectations of the Nation, and to do what is right, despite 

easier options that may present themselves. 

Assessment Summaries 

Listed in numerical order, this is a summary of the Task Group assessments of the Agency’s 

implementation of the 15 CAIB return-to-flight recommendations. More detail may be found 

in other sections of this report. 

CAIB Recommendation 3.2-1: External Tank Debris Shedding. The physical cause of the 

loss of Columbia and its crew was a breach in the Reinforced Carbon-Carbon on the leading 

edge of the left wing. This was the result of an impact by a piece of insulating foam that 

separated from the left bipod ramp section of the External Tank. During entry this breach 

allowed superheated air to penetrate through the leading edge insulation and progressively 

melt the aluminum structure of the left wing, resulting in a weakening of the structure until 

increasing aerodynamic forces caused loss of control, failure of the wing, and the break-up of 

the Orbiter. To prevent a recurrence, the CAIB wrote this recommendation to initiate an 

aggressive program to eliminate all debris shedding from the External Tank. 

Unfortunately, it has proven impractical to eliminate all debris shedding from the External 

Tank. Therefore, NASA went to extensive lengths to better understand the debris environment 

and the amount of impacts the Orbiter could tolerate without critical damage. Most efforts 

were ultimately focused on achieving a balance between the debris shed by the ET and the 

ability of the Orbiter to tolerate the debris. 

Page 14 of 216 
Final Report of the Return to Flight Task Group 

The Agency and its contractors modified the External Tank to eliminate the bipod ramp foam 

that was the physical cause of the Columbia accident. The processes for manual application of 

foam insulation have been changed to include greater process control and quality inspection. 

An extensive effort has resulted in a new understanding of foam and ice and what causes them 

to shed from the tank during ascent. Heaters have been added to areas of the External Tank to 

impede the formation of ice, and various other flaws in the design and manufacture of the tank 

were discovered and corrected along the way. 

The RTF TG concluded that NASA did not meet the intent of CAIB Recommendation 3.2-1. 

Despite a great deal of excellent work on the part of the Agency and its contractors, the 

External Tank still sheds debris that could potentially cripple an Orbiter. The extensive work 

to develop debris models and transport analysis was, until recently, hampered by a lack of 

rigor in both development and testing. The debris-allowable requirements provided to the ET 

Project did not match what was later determined to be the impact tolerance of the Orbiter. 

That being said, the Task Group believes that the ET Project worked diligently to successfully 

meet the requirements they were provided; unfortunately, those requirements were later 

determined to be inadequate. 

CAIB Recommendation 3.3-1: Reinforced Carbon-Carbon Non-Destructive Inspection. 

The accident board was surprised at how little was known about the impact resistance and 

effects of aging on the Reinforced Carbon-Carbon used as part of the Orbiter Thermal 

Protection System. They recommended that NASA re-baseline all of the RCC components on 

each remaining Orbiter and also take advantage of advanced non-destructive inspection 

technology that was not available when the Space Shuttle Program began. 

The RTF TG concluded that NASA met the intent of CAIB Recommendation 3.3-1 after the 

Agency removed all nosecap, chin panel, and wing leading edge RCC from each of the 

Orbiters and returned them to the manufacturer for evaluation. Testing methods used by the 

manufacturer included the same evaluations done during the original acceptance testing, as 

well as new technologies. It should be noted that this action did not physically change the 

condition of the Orbiter. 

CAIB Recommendation 3.3-2: Orbiter Hardening. The Columbia accident clearly 

demonstrated that the Orbiter Thermal Protection System, including the Reinforced CarbonCarbon panels and acreage tiles, was vulnerable to impact damage from the existing debris 

environment. 

The RTF TG concluded that despite tremendous effort by NASA and its contractors, the 

Agency did not fully meet the intent of CAIB Recommendation 3.3-2, due to the present lack 

of a long-term approach to RCC hardening and the amount of remaining non-standard work 

coming out of the various design verification reviews. An early long-term plan for Orbiter 

hardening was abandoned after the National Policy decision to retire the Space Shuttle fleet 

no later than 2010. Nevertheless, through an extensive test and analysis effort, the Agency has 

learned a great deal about the impact resistance of the Orbiter and has better defined damage 

criteria. NASA has provided some increased hardening through hardware changes, but the 

Orbiter is still vulnerable to the debris environment created by the External Tank. The Space 

Shuttle Program has acknowledged the possibility of critical debris damage and has 

developed an accepted risk rationale. 

CAIB Recommendation 3.4-1: Ground-Based Imagery. The Columbia post-accident 

investigation was hampered by the lack of high-resolution imagery of the vehicle during 

ascent. The CAIB was concerned about the need to have an adequate number of appropriately 

located cameras that operated properly to provide photographic coverage of the Space Shuttle 

from launch through separation of the Solid Rocket Boosters. 

The RTF TG concluded that NASA met the intent of CAIB Recommendation 3.4-1 by 

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increasing the number and capability of ground camera assets. Also, the Agency has arranged 

for airborne assets to mitigate the effects of cloud cover and improve higher altitude 

resolution, at least for the first two launches. From a hardware asset perspective, these 

changes should ensure an adequate capability to provide three useful views. 

CAIB Recommendation 3.4-2: High-Resolution Images of External Tank. Although the 

Space Shuttle Program routinely attempted to photograph the External Tank after separation 

using hand-held cameras on the flight deck and film cameras in the Orbiter umbilical wells, 

none of these images were downlinked to the ground, and the STS-107 images were therefore 

unavailable to the CAIB. The accident board recommended that high-resolution imagery of 

the ET be obtained on each flight and downlinked to the ground as soon as practical after 

achieving orbit. 

The RTF TG concluded that NASA met the intent of CAIB Recommendation 3.4-2 by 

planning to use handheld camera images taken from the Orbiter flight deck and the addition of 

a digital umbilical well camera. The images from these cameras will be downlinked for 

evaluation during the first days on orbit. 

CAIB Recommendation 3.4-3: High-Resolution Images of Orbiter. This was a concern to 

the CAIB because their investigation was hampered by the lack of high-resolution images. 

The accident board recommended that NASA provide a capability to obtain and downlink 

high-resolution images of the underside of the Orbiter wing leading edge and the forward 

portion of the Thermal Protection System tiles under both wings. 

The RTF TG concluded that NASA met the intent of CAIB Recommendation 3.4-3 through 

the addition of the Orbiter Boom Sensor System (OBSS) with two sensor packages and the 

R-Bar Pitch Maneuver(RPM) imagery from the ISS. A full scan of the wing leading edge and 

nosecap will be accomplished by OBSS on Flight Day 2 with the capability for specific, 

detailed inspections on later flight days. Additional imagery is provided through several 

cameras on the External Tank and Solid Rocket Boosters. The Task Group cautions, however, 

this on-vehicle imagery suite does not provide complete imagery of the underside of the 

Orbiter or guarantee detection of all potential impacts to the Orbiter. 

CAIB Recommendation 4.2-1: Solid Rocket Booster Bolt Catcher. While investigating the 

cause of the Columbia accident, the CAIB noted that the Solid Rocket Booster bolt catchers 

had not been properly flight-qualified. Each SRB is connected to the External Tank by four 

separation bolts: three at the bottom plus a larger one at the top that weighs approximately 65 

pounds. Bolt catchers cover each bolt to capture the pieces after the bolt is explosively 

separated during staging. Static and dynamic testing, conducted as a result of the accident 

board’s inquiries, demonstrated that the bolt catchers flown on STS-107 had a factor of safety 

of 0.956, rather than 1.4 required by specification. 

The RTF TG concluded that NASA has gone well beyond the intent of the CAIB in 

answering CAIB Recommendation 4.2-1. Instead of simply qualifying the existing bolt 

catchers, NASA undertook an extensive redesign, and then qualified the new design. 

CAIB Recommendation 4.2-3: Two Person Closeout Inspections. While reviewing various 

security aspects of the Space Shuttle Program to eliminate terrorist activity or sabotage as 

possible causes of the Columbia accident, the CAIB noted a lapse in procedures at various 

NASA installations. There were several processes that did not require two people to be 

present when an area on the flight vehicle was closed-out (sealed prior to flight). Although 

unlikely, this could allow an individual to sabotage the vehicle without being observed, and 

was also against the general policy of “two sets of eyes are better than one” that provides 

additional technical and safety checks during closeouts. It is important to note, however, that 

the CAIB found no evidence that willful damage was a cause of the accident (Finding 4.2-12). 

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The RTF TG concluded that NASA had met the intent of CAIB Recommendation 4.2-3 

through revised procedures at all locations that now require at least two people to be present 

during a closeout. 

CAIB Recommendation 4.2-5: Kennedy Space Center Foreign Object Debris Definition. 

During January 2001 the Kennedy Space Center generated new and non-standard definitions 

for Foreign Object Debris (FOD). The term “processing debris” was applied to debris found 

during the routine processing of the flight hardware. The term FOD applied only to debris 

found in flight hardware after final closeout inspections. These definitions were unique to the 

Space Shuttle Program at KSC. Because debris of any kind has critical safety implications, 

the CAIB wanted the standard, industry-wide definition reestablished for FOD. 

The RTF TG concluded that NASA met the intent of CAIB Recommendation 4.2-5 when 

KSC and the United Space Alliance changed the definition of “Foreign Object Debris” to be 

consistent with the recognized and accepted industry standard. Further, the Agency has 

removed the misleading category of processing debris that caused concern. They have 

improved the training of the workforce and implemented several improvements above and 

beyond the expectations defined in the CAIB recommendation. 

CAIB Recommendation 6.2-1: Consistency with Resources. The CAIB explicitly 

recognized the legitimate use of schedules to drive a process, but was concerned, however, 

that the line between “beneficial” schedule pressures and those that become detrimental 

cannot be defined or measured. In the case of Columbia, the CAIB discovered that pressure 

on the Space Shuttle Program was created by the schedule for construction of the 

International Space Station. Indeed, the planned February 2004 completion of Node 2 of the 

ISS was being touted as a measure of NASA’s ability to maintain a schedule that had been 

promised to Congress. 

The RTF TG concluded that NASA met the intent of CAIB Recommendation 6.2-1, since 

new tools and processes put in place by the Agency should preclude this type of undue 

schedule pressure in the future. The Task Group cautions, however, that resource sufficiency 

is also tied to the scheduled retirement date for the Space Shuttle. Any evaluation of plans to 

keep the Space Shuttle in service past 2010 should include a reassessment of actions and 

upgrades not undertaken by NASA, and any long-term items already deleted from work and 

acquisition cycles, including the Service Life Extension Program. 

CAIB Recommendation 6.3-1: Mission Management Team Improvements. The 

performance of the Mission Management Team (MMT) during the flight of Columbia has 

been widely criticized. Many of the additional capabilities embedded in other 

recommendations from the CAIB, such as imagery from various sources and vehicle damage 

tolerance maps, are intended to support MMT activities for the return to flight. The CAIB 

recommended that the MMT receive additional training to deal with potential crew and 

vehicle safety contingencies beyond the launch and ascent phases of flight. 

The RTF TG concluded that NASA has met the intent of CAIB Recommendation 6.3-1 by 

developing a new training plan for the MMT. With the passage of time, the Task Group has 

been able to observe the implementation of most aspects of the plan. Numerous simulations 

have been conducted, including more than 10 involving live, face-to-face exercises of various 

parts of the next mission. The various delays in launching STS-114 have allowed the MMT to 

further refine its procedures and have resulted in continual improvement. The Mission 

Management Team has made notable progress in addressing the CAIB concerns, and the 

Agency has demonstrated a commitment to continual MMT improvement. 

CAIB Recommendation 6.3-2: National Imagery and Mapping Agency Memorandum of 

Agreement. There was considerable public discussion of the decision during the flight of 

Columbia to forego requesting the assistance of other federal agencies in assessing the 

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condition of the Orbiter, including any possible damage. The CAIB wanted the Space Shuttle 

Program to have the procedures in place to get all possible data to investigate a potential 

problem. This included having the proper personnel maintain the appropriate security 

clearances to access data from National assets. 

The RTF TG has concluded that NASA has met the intent of CAIB Recommendation 6.3-2. A 

revised Memorandum of Agreement is in place between NASA and the National GeospatialIntelligence Agency (NGA – the successor to NIMA), and appropriate security clearances 

have been obtained by various NASA personnel. The coordination required to use this 

capability has also been exercised in various MMT simulations. 

CAIB Recommendation 6.4-1: Thermal Protection System Inspection and Repair. This 

was a four-part CAIB recommendation. The RTF TG only assessed the parts of this 

recommendation applicable to inspection and repair for the return-to-flight effort. 

After long and often spirited discussion, the RTF TG concluded that NASA did not meet the 

intent of CAIB Recommendation 6.4-1 relative to repair of the Orbiter Thermal Protection 

System; the inspection part included in the assessment of Recommendation 3.4-3 did meet the 

intent of CAIB. The basic debate within the Task Group was more one of process than of fact; 

everybody agrees that the repair options on STS-114 “are what they are.” The Task Group 

opinion – by a slim margin – was that each of the repair options that comprise the repair 

capability must be sufficiently tested and vetted so that NASA could implement it in an 

emergency situation with confidence that it would perform as expected. To date, the tile and 

RCC repair techniques developed by the Agency are not considered sufficiently mature to be 

a practicable repair capability for STS-114. 

CAIB Recommendation 9.1-1: Detailed Plan for Organizational Change. The CAIB 

expected NASA to return to flight relatively quickly, and the accident board did not want to 

restrict this activity by requiring major organizational changes. Instead, the CAIB wrote a 

separate recommendation that NASA produce a detailed plan to implement the organizational 

changes embodied in three other recommendations – R7.5-1, Independent Technical 

Authority; R7.5-2, Safety and Mission Assurance; and R7.5-3, Systems Engineering and 

Integration. However, getting ready for the first return-to-flight mission took much longer 

than initially expected, allowing NASA to proceed with many of the organizational changes 

recommended by the CAIB. The Task Group elected to assess the actual changes, in addition 

to the plan. 

The Task Group believes that embodied in Recommendation 9.1-1, however, are a myriad of 

organizational and management issues raised by the CAIB, including “culture.” The CAIB 

used the term “culture” throughout its report, although there are neither specific 

recommendations to change culture nor any suggestions on how this might be accomplished. 

Therefore, organizational culture, although important, was not considered a return-to-flight 

issue and was not evaluated by the Task Group. 

The RTF TG concluded that NASA has met the intent of CAIB Recommendation 9.1-1 

because the Agency has a mature plan to restructure the organization as envisioned by the 

accident board. The assessment of the actual changes, however, is mixed. The planned 

implementation of the Independent Technical Authority comports with CAIB intent, but 

resistance to this formulation still exists – it will take time to see if the process is robust 

enough to overcome the internal opposition. The planned response to R7.5-2 is intentionally 

not consistent with the CAIB recommendation – NASA simply disagrees that the best 

organization is for the field centers’ Safety and Mission Assurance Offices to report directly 

to Headquarters; the Task Group is sympathetic to the NASA position. Implementation of 

R7.5-3 is uneven, with improved integration and system analysis but with some worrisome 

gaps in system engineering capability. 

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CAIB Recommendation 10.3-1: Digitize Closeout Photos. During the Columbia 

investigation, the accident board encountered numerous engineering drawings that were 

inaccurate. Further, they discovered that a large number of engineering change orders had not 

been incorporated into the drawings. Tied in with this, in many instances CAIB investigators 

were not able to access needed closeout photography for several weeks. 

The RTF TG has concluded that NASA has met the intent of CAIB Recommendation 10.3-1. 

Standardized 6.1-megapixel cameras have been acquired for use in closeout and configuration 

photography. NASA identified enhancements to the Shuttle Image Management System 

(SIMS) database, and necessary upgrades are complete. Updated training material has been 

developed for users of the SIMS database, and users have received training at KSC, JSC, and 

MSFC. Through several integrated launch countdown simulations, the Space Shuttle Program 

staff have confirmed that the modifications to the SIMS database satisfy their needs. 

The CAIB recommendation assumed that the Space Shuttle Program would continue for the 

long term, and it indicated that the digital photography should be an interim solution pending 

the digitizing and updating of all Space Shuttle engineering drawings (R10.3-2). However, 

based on the decision to retire the Space Shuttle no later than 2010, the Task Group concurs 

with NASA’s decision that it does not make economic sense to expend the resources to make 

major changes in the drawings. The digital closeout photography provides an adequate 

solution until the end of the program. The Task Group cautions, however, that should the 

decision be made to extend the Space Shuttle Program past 2010 – or to use elements of it for 

a new heavy-lift vehicle – the appropriate engineering drawings should be resolved. 

Raising the Bar Action SSP-3: Contingency Shuttle Crew Support. The CAIB report 

mentioned the feasibility of providing contingency life support on board the International 

Space Station for stranded Space Shuttle crewmembers until repair or rescue could be 

accomplished. The accident board, however, did not issue a specific recommendation to either 

evaluate or implement such a capability. As part of the return to flight efforts, NASA 

developed a capability called Contingency Shuttle Crew Support aboard the ISS for STS-114 

and STS-121. Since this capability was an option of last-resort in several scenarios evaluated 

by the RTF TG, the Task Group elected to evaluate the capability as part of this report. 

The RTF TG concluded that NASA has developed analyses and plans for CSCS which will 

offer a viable emergency capability for crew rescue. NASA set a raising the bar action and 

exceeded it by a significant margin. The Task Group commends NASA for excellent work on 

SSP-3. 

Integrated Vehicle Assessment. To assess the ability to perform an integrated vehicle 

external damage assessment, the RTF TG established the Integrated Vehicle Assessment SubPanel (IVASP). With the addition of new cameras and sensors, NASA needed a method to 

capture and integrate the information gained from these sensors, use that information to 

perform a damage assessment, and present that information in a way that supported critical 

decision-making regarding potential damage and options to mitigate that damage. 

Beginning from scratch, NASA has developed a process that holds the promise of integrating 

a variety of new and disparate types of data into information that can support these complex 

decisions during flight. They have documented these processes, vetted them, trained to them, 

and revised them accordingly. As we have said, NASA needs an ability to manage risk during 

flight; NASA’s processes to integrate these sensor data into information that can support 

damage assessments represent a significant step in that direction. 

The Task Group commends NASA for its progress in this area and recommends that this work 

continue after STS-114. We further suggest that this process could even serve as a model for 

other cross-NASA integration projects. 

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Concluding Thought 

To focus solely on the CAIB return-to-flight recommendations as a measure of the safety of 

STS-114 is inappropriate. The Task Group, while concluding that three recommendations 

were not fulfilled in their entirety, was not chartered to reach any conclusion regarding the 

safety of the next flight. Indeed, addressing the CAIB recommendations has been only a part 

of the Agency’s vast work leading to return to flight. It is improper to calculate, on the basis 

of the Task Group’s assessments, the likelihood of success for the next and subsequent flights. 

It is the responsibility of NASA, and only NASA, to define and accept the remaining risk for 

STS-114 and all subsequent missions. 

The Columbia Accident Investigation Board provided a valuable service to the Columbia 

families, NASA, and the Nation by determining the cause of the accident and prescribing 

steps to reduce the risk for subsequent flights. As with most accident boards, the CAIB set a 

high standard, perhaps one that was not achievable given the technology, funding, and 

schedule available to the Space Shuttle Program. Not everything the CAIB recommended 

could be accomplished, but this does not reflect poorly on the dedication or capabilities of the 

NASA workforce. The work accomplished since February 2003 has led to an improved 

vehicle and an enhanced understanding of its capabilities and limitations. In addition, NASA 

has begun to address organizational changes that should clarify lines of communication and 

responsibilities to provide an enhanced safety culture. Perhaps the most important lesson from 

the accident is a renewed respect for the risks inherent in space travel and the need to 

continually monitor and assess those risks. 

Space Center 

awaiting launch as 

STS-114. 

Discovery sits at 

Launch Complex 

39B at the Kennedy 

Page 20 of 216 
1 

Final Report of the Return to Flight Task Group 

BACKGROUND 

It has been 24 years since the first launch of Columbia marked the beginning of the Space 

Shuttle Program’s flight phase. During the course of 113 missions, the program suffered two 

tragic flight accidents, costing the lives of 14 astronauts. Despite this, the Space Shuttle is the 

most reliable human spacecraft ever built; reports of it being inherently unsafe do not fully 

take into account the physics or technology involved in boosting a payload off the surface of 

the Earth. 

Space, by its nature, is a hostile environment posing unique risks for any undertaking, 

especially those involving humans. The speeds, pressures, temperatures, and stresses involved 

in space flight are unparalleled in the normal Earth-bound environment in which we all live. 

There are other environments in which humans operate – in the deep sea, for instance – that 

are equally as harsh, at least in some respects, but none are as unforgiving as space flight. 

Everybody involved with the Space Shuttle Program strives – as they should, and must – for 

perfection. But all understand that despite their best efforts, it is highly unlikely they will ever 

be able to make space travel risk free. Nevertheless, perfection must continue to be the goal, 

for anything less is clearly unacceptable. 

When the Columbia Accident Investigation Board (CAIB) issued its final report in August 

2003, it included several recommendations that ultimately were not met. The CAIB 

understood this possibility, but it is the job of any accident board to identify all of the 

deficiencies it uncovers during its deliberations. The CAIB went further than most accident 

boards since it was dealing with a very complex and publicly-visible program. As the accident 

board wrote in its final report, “It is our view that complex systems almost always fail in 

complex ways, and we believe it would be wrong to reduce the complexities and weaknesses 

associated with these systems to some simple explanation.” 

Then-Administrator Sean O’Keefe embraced the CAIB recommendations and directed the 

Agency to implement all of them. This was undoubtedly the correct motivation at the time; 

the Space Shuttle was expected to remain in service for another 20 years or more. However, 

circumstances change. For the American space program, a major shift occurred on January 

14, 2004, when President George W. Bush announced the Vision for Space Exploration that 

will send astronauts back to the moon, and eventually to Mars. As part of this Vision, the 

President ordered that the Space Shuttle be retired no later than 2010, only 5 years after the 

return-to-flight of Discovery. 

This shift in National Policy had a major effect on the effort to return the Space Shuttle fleet 

to flight. NASA determined that there was no longer sufficient time, nor would it be prudent, 

to implement several of the CAIB recommendations; others must be reconsidered from a 

budgetary and schedule perspective given the limited number of missions remaining to be 

flown before the Space Shuttle is retired. 

The Return to Flight Task Group was not chartered to pass judgment on the CAIB report, but 

rather to assess the Agency’s implementation of the 15 recommendations the accident board 

indicated should be completed prior to returning to the Space Shuttle to flight. It was 

completely within the purview of NASA to determine if the recommendations were still valid 

given the new circumstances surrounding the future of the program. In several instances, 

NASA decided that it was not feasible to implement the CAIB recommendations in their 

entirety. The Task Group understands, and in some instances concurs, with the reasoning 

behind these decisions, but must still determine the Agency’s compliance with the 

recommendations as written and without reference to recent changes in the National Policy 

for space exploration. 

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Final Report of the Return to Flight Task Group 

Over the course of its 25-year history, the Space Shuttle Program has averaged just over four 

flights per year, a rate that has never allowed the system to fully mature as its designers 

originally intended. Nevertheless, the Space Shuttle has transported more people, from more 

countries, into space than all other launch vehicles combined. However, as the CAIB report 

correctly pointed out, the Space Shuttle is not now, has never been, nor will ever be, an 

“operational” vehicle. Instead, it is a developmental vehicle performing a dangerous mission 

in a known high-risk environment. Measured against similar systems, it has excelled at its 

task, but it can, and should have, done better. 

The Task Group – like the CAIB before it – does not believe that the Space Shuttle is an 

inherently unsafe vehicle. On the contrary, the Task Group believes it is a remarkable 

technological achievement that has served the Nation well for over 20 years. NASA and the 

aerospace industry have learned a great deal in those years, and the next vehicle will, 

hopefully, be safer and more reliable than the Space Shuttle. Nevertheless, constant vigilance 

will always be required to ensure NASA does not become complacent about the dangers of 

space flight. But we would be deceiving ourselves, and the American public, if we proclaimed 

that space travel will ever be “safe.” As the CAIB observed, “Building rockets is hard.” 

Building rockets for human travel is even harder. 

The United States has committed to human spaceflight, and in doing so, has also committed to 

accepting the risks associated with that endeavor, with the belief that our knowledge, skill, 

and perseverance will allow us to succeed. This will never be a safe, easy, or routine 

undertaking. The Administration, Congress, and the American public must be made aware of 

the dangers inherent in the technology and environments of space exploration. They must be 

assured that NASA and its contractors have done, and will continue to do, everything within 

their power to minimize the risks involved in this great undertaking. But they must also 

realize that it is likely that another accident will happen in the future; if not with Space 

Shuttle, then with whatever vehicle replaces it. 

The Space Shuttle Program must strive to identify and understand every potential risk – 

technical and programmatic – to the vehicle and crew. It must eliminate risk wherever 

possible, take steps to mitigate those risks that it can not eliminate, and carefully monitor 

those risks that it cannot control. The program must ensure that it is its own harshest critic 

since the vehicle and its environments are so complex that nobody will ever understand them 

better than the program itself. To accomplish this, NASA leadership must provide proactive 

oversight to ensure that the Space Shuttle Program does not overlook risks by being “too close 

to the problem.” In turn, the program must be completely honest with itself, NASA 

leadership, Congress and the American public, never minimizing the risks inherent in space 

flight, never making it appear to be easier than it is, and never forgetting that the price of 

failure is too high. Nothing less will honor the legacy of the 14 astronauts who perished in 

Challenger and Columbia. 

the setting sun 

paints a silhouette of 

(on the 

right) as it rolls out to 

Space Center in 

first mission after the 

loss of . 

The orange glow of 

Discovery

Launch Complex 

39B at the Kennedy 

preparation for the 

Columbia

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Final Report of the Return to Flight Task Group 

2 RELATIONSHIPS AMONG THE RECOMMENDATIONS 

A large majority of the CAIB return to flight recommendations rely on the results of other 

recommendations and should be placed in context to properly evaluate and appreciate the 

volume of work accomplished by NASA over the last two years. In many instances, the Task 

Group could not easily assess one recommendation without considering others. With few 

exceptions (R4.2-5; KSC Foreign Object Debris, and R4.2-3, Two Person Closeout 

Inspections), all of the technical and operational recommendations were closely linked via 

their relationship to the overall risk acceptance rationale used by NASA. In addition, the 

Agency’s response to the management recommendations influenced how the other 

recommendations were ultimately implemented. 

There was initial consideration within the Task Group of combining the assessments of 

several recommendations in this report, but ultimately it was believed that each assessment 

should stand alone – to the extent possible – to make it easier for the reader to locate the 

particular recommendation. However, it was also felt that it was necessary to explain the 

relationships among the recommendations. 

A similar quandary apparently confronted NASA. An early attempt within the NASA Safety 

and Mission Assurance community to integrate the intent of the recommendations into a 

whole came in the form of the Thermal Protection System Risk Reduction Framework, 

presented below. Using this framework, a larger picture emerges of the NASA 

implementation of the CAIB return-to-flight recommendations. 

2.1 Thermal Protection System Risk Reduction Framework 

The most important technical issue to be resolved before returning to flight was preventing 

ascent debris from causing critical damage to the Orbiter Thermal Protection System. The 

Space Shuttle Program Safety and Mission Assurance Manager described a proposed 

framework for thermal protection system risk reduction to the RTF TG at the April 2004 

plenary. This framework, starting with primary hazard control, further delineated appropriate 

warning devices and special procedures to mitigate the risk of the primary hazard control not 

being completely satisfied, and directly encompassed several of the CAIB return-to-flight 

recommendations. The Task Group found this useful for putting various recommendations in 

context with one another. 

The primary hazard control, or the first step in the roadmap, was to “Eliminate Critical 

Debris.” This was a combination of subparts: understand and improve the current ability of 

the Orbiter to withstand debris impacts (R3.3-2), ensure that the reinforced carbon-carbon 

panels currently in use were not already damaged (R3.3-1), and attempt to eliminate ascent 

debris (especially from the External Tank, R3.2-1, and SRB bolt catchers, R4.2-1). 

Warning devices encompassed the second and third steps in the roadmap. The second step, 

“Impact Detection During Ascent,” covered ground-based imagery (R3.4-1), high-resolution 

imagery of the ET (R3.4-2), observation cameras mounted on the ET and SRBs (a component 

of R3.4-3), data from National assets (R6.3-2), and data from the wing leading edge impact 

detection system (a component of the inspection portion of R6.4-1). Step III, “On-Orbit 

Debris Impact/Damage Detection,” dealt with the Orbiter Boom Sensor System (OBSS) and 

R-Bar Pitch Maneuver imagery taken from the International Space Station that are part of the 

inspection portion of R6.4-1 and which provide the high-resolution capability to meet R3.4-3. 

An implicit step in this roadmap was the integration of data from the warning devices into an 

assessment of any damage sustained by the Orbiter Thermal Protection System during the 

mission. The combination of that data with the knowledge of the capability of the Orbiter to 

enter with damage (the second part of R3.3-2) and closeout photography depicting the last 

Page 23 of 216 
Final Report of the Return to Flight Task Group 

known state of the Orbiter (R10.3-1), results in a determination of whether repair (the other 

part of R6.4-1) needs to be initiated. Additionally, test and analysis provide the rationale to 

continue with entry or invoke the safe haven offered by Contingency Shuttle Crew Support 

(CSCS – SSP-3). The integration of this data has been the primary focus of the Task Group’s 

Integrated Vehicle Assessment Sub-Panel (IVASP) and is further addressed in Section 2.2. At 

the Task Group’s urging, MMT simulations (R6.3-1) and component simulations (R3.3-2 and 

R6.4-1) exercised the resulting process. However, the Task Group cautions that limitations in 

these inspection capabilities may still allow damage to go undetected. 

The last two steps, which hopefully will never need to be exercised during a mission, are 

called “Special Procedures.” Step IV, “On-Orbit TPS Repair (Tile and RCC),” is addressed in 

the repair portion of R6.4-1. The final step of the roadmap, “Safe Haven and Crew Rescue,” is 

the focus of the “raising the bar” action for CSCS (SSP-3) that the Space Shuttle Program 

assigned to itself, and is not a direct response to a CAIB recommendation. 

On the management side, expanding the role of the Space Shuttle Integration Office to 

address the entire Space Shuttle system (R7.5-3) enabled the new Systems Engineering and 

Integration Office (SEIO) to lead the effort to understand the effects of debris, to assess the 

remaining risk due to critical debris, and to integrate the in-flight TPS assessment activities. 

Many of the efforts in the paragraphs above entail development activities, and therefore carry 

the possibility that some requirements may not be met and waivers will need to be processed. 

Restoring specific engineering technical authority, independent of programmatic decisionmaking (R7.5-1) and increasing the authority, independence, and capability of the Safety and 

Mission Assurance (SMA) organizations (R7.5-2) provide independent voices in the waiver 

and resulting risk acceptance deliberations that the CAIB felt were missing at the time of the 

Columbia accident (R9.1-1). 

Clearly, the more thoroughly critical debris can be eliminated (via a combination of reducing 

debris from the tank and increasing the ability of the Orbiter to withstand impacts), the less 

important the repair capability (with its attendant prerequisite ability to detect damage which 

needs to be repaired) or the rescue capability becomes. The more confidence in the detection 

and repair capabilities there is, the less the need for a crew safe haven and rescue function 

Page 24 of 216 
Final Report of the Return to Flight Task Group 

exists. The crew rescue capability is only a last resort (no matter the confidence one has in it) 

because in this case, the crew is saved; however, the damaged Orbiter is not salvaged. In 

addition, invoking CSCS would have significant impacts on the ISS, including the possible 

need to evacuate the station. 

All of the steps in the roadmap have remaining uncertainties associated with them (see the 

column on the right of the diagram). There still exists a possibility that the Orbiter could 

sustain critical damage to the TPS. Limited actions were taken to harden the Orbiter, and there 

is a potential that debris from the External Tank could again critically damage an Orbiter 

during ascent. If such damage occurs, there is some risk that it could go undetected, not be 

repairable, or that a rescue mission could not be launched in time. Probabilistic analysis was 

used to quantify the residual risk of critical damage to the Orbiter Thermal Protection System 

from debris and is discussed in Section 3.3 as part of R3.3-2. Other risks are captured in the 

Integrated Hazard Reports. 

NASA acknowledges that the elimination of all critical debris is not attainable; therefore the 

Agency has analyzed and formally accepted the remaining risk as a condition for the return to 

flight. 

2.1.1 Summary 

Many within the RTF TG were encouraged with this proposed “top-down” approach for 

hazard reduction. Similarly, it would have been beneficial if NASA had performed a topdown requirements flow-down that recognized the relationship between seemingly 

disconnected system elements with cross-cutting functional connectivity. Some members of 

the Task Group expressed an interest in seeing this implementation technique applied to all 

items in the NASA Implementation Plan, but no evidence of this approach was found by the 

Task Group. The failure to accomplish these tasks may ultimately result in unintended 

consequences from a lack of integration between elements. 

The basic outline of the roadmap presented at the April 2004 plenary was eventually 

incorporated into a Headquarters document, The Integrated Risk Acceptance Approach For 

Return To Flight, intended to define the overall rationale for STS-114. The Task Group notes, 

however, this document has not been formalized – it has no author, no document number, no 

approval page, apparently no configuration management – and does not directly correlate to 

any program requirements. Nevertheless, progress has been made in incorporating risk 

reduction as part of various program, element, and project activities. 

2.2 Integrated Vehicle Assessment 

The RTF TG established the Integrated Vehicle Assessment Sub-Panel (IVASP) to combine 

insights from the Operations, Technical, and Management Panels in order to assess NASA’s 

ability to perform an integrated external damage assessment of the Orbiter based on a variety 

of data sources in direct support of real-time decision-making for Space Shuttle operations. 

2.2.1 The NASA Response 

As part of their return to flight effort, NASA developed a Orbiter Thermal Protection System 

readiness determination concept. This is documented in NSTS 60540, STS-114 Operations 

Integration Plan for Thermal Protection System Assessment, baselined April 12, 2005. This 

document states its intended purpose as, “This Operations Integration Plan (OIP) is the 

agreement on the responsibilities and tasks which directly relate to the integration activities 

associated with the successful system engineering, integration, and verification of the Space 

Shuttle return to flight activities associated with the assessment of the TPS. These operations 

are intended to provide the processes for transforming the data from the TPS assessment 

Page 25 of 216 
Final Report of the Return to Flight Task Group 

NASA timeline to 

collect, process and 

assess ascent and 

on-orbit data to 

determine the state 

of the Orbiter 

Thermal Protection 

System during a 

mission. 

systems into information that can be used by Mission Management to make a timely TPS 

entry readiness, repair, or safe haven determination. This document constitutes an agreement 

on the part of participating organizations concerning products and tasks described.” 

The OIP is the response to Program Requirements Control Board (PRCB) Directive S064005, 

Action 14-1, to develop an integrated operations concept for ascent film and video, Orbiter 

umbilical well cameras, Orbiter Boom Sensor System inspection, wing leading-edge 

instrumentation, and external resources. The document also includes the plan for integration 

of pad walk down debris reports, ascent radar, Solid Rocket Booster recovery reports, 

International Space Station photography during the R-bar Pitch Maneuver, and debris 

transport analysis. In addition, the OIP includes an Annex, Orbiter Damage Assessment 

Process, that documents the damage assessment process, and the decision timeline required to 

support a safe entry assessment. The document focuses specifically on a description of the 

operations, the work and analysis to be performed, process dependencies, process flows, 

process responsibilities, and the verification requirements from an integrated perspective. 

0 1 2 3 4 5 6 7 8 9 

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i i i

/

isi

6 7 8 9 

Anal

isi

DTO 

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f

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EVA Cabin 

Repai

ir 

) 

MET 10 11 12 13 14 

FD1 

Asc 

Collect imagery & data 

Process ana yze imagery & data 

Orbiter damage assessment 

Decis on:focused inspect on requ red? 

Collect OBSS inspection data 

Process analyze OBSS inspection data 

Orbiter damage assessement 

Dec on: Repair required? 

10 11 12 13 14 

Downlink EVA photos 

yze EVA photos 

Collect OBSS inspection data 

Analyze OBSS inspection data 

Orbiter repair assessment 

Dec on: ready for undock? 

ORM, 

Redock 

OBSS 

inspect 

Inspection 

EVA 1 

install, Tile Repair 

OBSS 

Focused 

SRMS logistics 

RPM, 

Surveys, 

OBSS & Trans er 

FD6 FD10 FD11 FD12 FD13 

MPLM 

FD2 FD3 FD4 FD5 FD7 FD8 FD9 

 Transfer 

log stics 

EVA 2 

CMG R&R 

EVA 3 MPLM Undock Cabin 

reberth 

FD12 FD13 

FD15 

Waveoff 

Day 1 

Waveoff 

Day 2 

FD14 FD15 

Undock, 

ORM 

FD14 

Entry 

FD7 FD8 FD9 FD10 FD11 

Waveoff 

Stow Day 1 

MPLM 

reberth 

Undock 

r, 

EVA to Entry 

verify 

repa

OMS HH

 Repair Required (ORM Nominal Mission FD4 Inspection 

The OIP was developed based on the assets baselined for STS-114 with a daylight launch 

constraint; however, many of the processes outlined in this document are generic in nature 

and could apply to any Space Shuttle mission. Nevertheless, due to the evolutionary nature of 

the specific complement of assets, it was necessary to address the specific STS-114 

configuration for the baseline release of the OIP. It is currently NASA’s intent to update the 

document for future missions as the asset configurations and timelines required to support 

decision-making change, as well as to capture changes to the process deemed necessary to 

better support decision-making. 

2.2.2 RTF TG Assessment 

The Task Group commends the OIP and Damage Assessment Annex developers. Beginning 

from scratch, they have evolved a process that holds the promise of integrating a variety of 

new and disparate types of data into information that can support complex decision-making 

Page 26 of 216 
Final Report of the Return to Flight Task Group 

during flight. To do this, the developers had to work across NASA boundaries to identify the 

best organization to be responsible for each data source. They had to secure commitments 

from these organizations to produce data analysis reports on a specified timeline and to share 

those reports through the OIP. They have also identified and established new positions of 

authority required to set priorities on data collection and analysis to meet emerging real-time 

needs. They have conducted an aggressive training plan to exercise each component of the 

assessment process as well as the MMT use of the information. Finally, they fully 

documented the process so that it can be evolved as data sources change, studied by new 

participants in the process, and evaluated by outside observers. 

The Task Group recognizes that the OIP and Damage Assessment Annex will continue to 

mature through STS-114 and, hopefully, beyond. NASA needs an ability to manage risk 

during flight, and these two documents represent a significant step in that direction. The 

CAIB recommendations identified specific data necessary to better understand the risk to the 

Orbiter of a debris impact. The Operations Integration Plan was developed to integrate the 

data from the new data sources developed for return-to flight and the Damage Assessment 

Annex was developed to clearly define how those data would be interpreted. We see the 

Space Shuttle Program’s experience in these development initiatives as having potential that 

goes beyond the specific Thermal Protection System assessment sources developed for STS114. It represents an approach that pulls information from across NASA boundaries into a 

consolidated, integrated “whole.” There will likely be other anomalous situations during flight 

where such an approach could help the decision-makers assess and manage risk. 

2.2.3 RTF TG Observations 

During its assessment of the OIP, the Task Group had several observations. 

2.2.3.1 OIP/Damage Assessment Annex Development and Documentation 

NASA should continue to support and resource the OIP and Damage Assessment Annex 

processes. Furthermore, their accomplishments should serve as a model for tackling other 

integration challenges that NASA faces. 

The Space Shuttle Program published several draft versions of the STS-114 Operations 

Integration Plan, culminating in the baseline version on April 12, 2005. Beginning in 

December 2004, NASA conducted a series of component simulations (sims), designed to test 

specific pieces of the OIP, and mini-integration simulations, designed to test parts of the 

process that involve integration. As elements of the OIP matured, they were incorporated into 

MMT simulations. These led to MMT sim #12, conducted in March 2005 that specifically 

included a number of Orbiter Thermal Protection System incidents requiring assessment. The 

Space Shuttle Program conducted a component sim the week prior to this MMT and used the 

outputs of the component sim as inputs to the full-scale MMT sim. 

The Space Shuttle Program also released a revised version of the Orbiter Damage Assessment 

Process Annex on March 1, in time to support MMT sim #12. The IVASP reviewed the first 

version of this Annex in December 2004. The current revision is more mature and includes a 

detailed description of the processes the program will use to take the data collected and 

integrated through the OIP and use it to actually assess the status of the Thermal Protection 

System. The Annex further includes frameworks for risk-versus-risk assessments for both tile 

and RCC damage and repair activities. This Annex should continue to be exercised in the 

component and mini-integration sims scheduled before flight. The Space Shuttle Program 

should update both the OIP and Annex before flight to incorporate the lessons they have 

learned from their work through the sims, as well as incorporate final decisions for STS-114 

resulting from the Debris DVR, the Program DCR, the FRR, and model validation. 

Page 27 of 216 
Final Report of the Return to Flight Task Group 

2.2.3.2 Structured Assessment during Flight 

During flight, the information and understanding gained from the STS-114 experience will be 

invaluable for future mission data integration. The Operations Integration Plan and Damage 

Assessment Process Annex developers should put in place a structured process to capture 

records of the data collected and the processes used to integrate and assess it during flight. 

The results of a review of this information coupled with the experiences of the participants 

should form the basis for the post-STS-114 OIP/Annex revisions. 

2.2.3.3 Critical Damage/Debris Size Definition 

The Space Shuttle Program must continue to mature its critical damage and critical debris 

assessments and incorporate the results into the OIP and Annex. The results of these 

assessments determine the operation and processing of some of the key sensors, such as those 

on OBSS. This could change the timelines the OIP has developed to ensure the data will be 

available to support the damage assessment process and associated key decisions. 

2.2.3.4 Camera Requirements Analysis 

During MMT sim #12, the participants debated the significance of the loss of a suite of 

ground cameras. Some participants felt that the camera’s “Criticality 3” status made clear that 

they were not a constraint to flight, while others felt that the loss would preclude collection of 

important mission-essential information. Before the launch of STS-114, the Task Group 

believes that the relative importance of each camera (as well as all STS-114 inspection and 

imagery capabilities) should be pre-determined, to the extent possible, so that there is a 

clearer basis for these decisions. The Task Group is not recommending that the criticality of 

these cameras be changed. Rather we believe that, with all the cameras and sensors now 

available to NASA, the implications of the loss of a particular sensor need to be clear as the 

trade-offs are debated. This is even more of a factor for STS-114 since one of its explicit 

objectives is to document the debris environment actually experienced. 

Because many of the cameras are redundant and because data are available at different times, 

this determination requires analysis. We believe the OIP developers have the expertise to do 

this work and the OIP is the best place to document the results. The Task Group recognizes 

that, for some views, there are so many cameras that it would be extremely time-consuming to 

detail all the permutations. While we still believe the full analysis should be done and 

documented eventually, it would be prudent for the OIP developers to focus on those views 

where there is little or no redundancy so that the implications of the loss of one or more of 

those systems are clear in time for the launch of STS-114. 

Additionally, resources must be made available to sustain the enhanced imagery capability 

that feeds the inspection and damage assessment for the remainder of the Space Shuttle 

Program. There are inherent risks in space flight and the ability to observe and analyze the 

state of the vehicle to a high degree of confidence will always be required. It is imperative 

that NASA accept the responsibility to protect this capability, to use it for all missions, and 

continue to evaluate methods to improve it within limits for the duration of the Space Shuttle 

Program and for future programs. 

2.2.4 Summary 

The OIP and its Damage Assessment Annex represent a significant step toward developing a 

process to integrate and assess a variety of important information from disparate sources. The 

Task Group commends NASA for its progress in this area and recommends that this work 

continue after STS-114. The Task Group further suggests that the development of the OIP and 

its Annex could serve as a model for other cross-NASA integration projects. 

Page 28 of 216 
3 

Final Report of the Return to Flight Task Group 

ASSESSMENT OF THE CAIB RECOMMENDATIONS 

What follows is a section for each of the 15 Columbia Accident Investigation Board (CAIB) 

return-to-flight recommendations and the “raising-the-bar” SSP-3 action; the three Chapter 7 

recommendations (R7.5-1, R7.5-2, and R7.5-3) that are subordinate to R9.1-1 are covered in 

Section 3.14. In each case the section repeats the original recommendation word-for-word, 

gives the RTF TG interpretation of the recommendation, provides a brief background (often 

taken directly from the CAIB report), details the NASA implementation, and concludes with 

the Task Group’s final assessment of the progress NASA made toward implementing the 

recommendation. 

The section entitled “NASA Implementation” contains descriptions taken from the 

appropriate version of the NASA Implementation Plan for Space Shuttle Return to Flight and 

Beyond, based on the date for the individual assessment was deliberated. (The RTF TG 

generally called this document the NASA Implementation Plan for brevity.) Additional 

information from the closure packages submitted by NASA, requests for information, and 

fact-finding activities are also included as necessary to ensure an adequate description. In 

general, the description presented in this section is a snapshot of the progress made when the 

Task Group concluded its assessment; in many cases, things changed between then and the 

release of this report. It is not the intent of the Task Group to “put words in NASA’s mouth” 

and in case of disagreement between this document and any official NASA publication, the 

NASA document shall prevail. 

The following table summarizes the Task Group’s assessment of the CAIB return-to-flight 

recommendations. 

Report 

Section 

CAIB 

Rec. # Recommendation Title 

Assessment 

Deliberated 

Task Group 

Assessment 

3.1 3.2-1 External Tank Debris Shedding June 27, 2005 Not Met 

3.2 3.3-1 Reinforced Carbon-Carbon 

Non-Destructive Inspection 

February 17, 2005 Met 

3.3 3.3-2 Orbiter Hardening June 27, 2005 Not Met 

3.4 3.4-1 Ground-Based Imagery June 8, 2005 Met 

3.5 3.4-2 High-Resolution Images of 

External Tank 

December 16, 2004 Met 

3.6 3.4-3 High-Resolution Images of Orbiter June 8, 2005 Met 

3.7 4.2-1 Solid Rocket Booster Bolt Catcher December 16, 2004 Met 

3.8 4.2-3 Two-Person Closeout Inspections December 16, 2004 Met 

3.9 4.2-5 Kennedy Space Center 

Foreign Object Debris Definition 

December 16, 2004 Met 

3.10 6.2-1 Consistency with Resources June 8, 2005 Met 

3.11 6.3-1 Mission Management Team 

Improvements 

June 8, 2005 Met 

3.12 6.3-2 National Imagery and Mapping 

Agency Memorandum of 

Agreement 

December 16, 2004 Met 

3.13 6.4-1 Thermal Protection System 

Inspection and Repair 

June 27, 2005 Not Met 

3.14 9.1-1 Detailed Plan for 

Organizational Change 

June 8, 2005 Met 

3.15 10.3-1 Digitize Closeout Photos December 16, 2004 Met 

3.16 SSP-3 Contingency Shuttle Crew Support June 8, 2005 n/a 

Page 29 of 216 
Final Report of the Return to Flight Task Group 

, atop a 

Mobile Launch 

The MLP is moved 

wi

containing 57 cleats 

moves at a 

i

 3 million pound 

Space Shuttle stack. 

on the MLP. 

Discovery

Platform (MLP), 

crawls toward 

Launch Complex 

39B on April 6, 2005. 

by the CrawlerTransporter 

underneath. The 

crawler stands 20 

feet high, 131 feet 

long and 114 feet 

de and moves on 

eight tracks, each 

weighing one ton 

each. The crawler 

maximum speed of 

approximately 0.8 

mile per hour while 

carry ng the 

Note the “We’re 

Behind You, 

Discovery” banner 

Page 30 of 216
Final Report of the Return to Flight Task Group 

3.1 CAIB Recommendation 3.2-1 – 

External Tank Debris Shedding 

Initiate an aggressive program to eliminate all External Tank Thermal Protection System 

debris-shedding at the source with particular emphasis on the region where the bipod struts 

attach to the External Tank. 

3.1.1 RTF TG Interpretation 

Eliminate all sources of critical debris in locations where liberated debris might impact the 

Orbiter, eliminate the bipod strut foam entirely if possible, and determine the foam void size 

that produces debris of an acceptable size based on the transport and energy analyses. 

3.1.2 Background 

The Columbia accident clearly demonstrated that the Orbiter Thermal Protection System, 

including the reinforced carbon-carbon (RCC) panels and acreage tiles, was vulnerable to 

impact damage from the existing debris environment. As a result, the Columbia Accident 

Investigation Board (CAIB) issued recommendations to eliminate debris (R3.2-1), determine 

the structural integrity of the RCC (R3.3-1), harden the Orbiter (R3.3-2) against impacts, and 

to develop on-orbit repair capabilities (R6.4-1). 

The External Tank (ET) is the largest element of the Space Shuttle system. Because it is the 

common element to which the Solid Rocket Boosters and the Orbiter are connected, the ET 

serves as the main structural component during stacking, launch, and ascent. Lockheed Martin 

builds the tank at the Michoud Assembly Facility, Louisiana, under contract to the NASA 

Marshall Space Flight Center. 

The External Tank is 153.8 feet long, 27.6 feet in diameter, and comprises three major 

sections: the forward (upper) liquid oxygen tank, the aft (lower) liquid hydrogen tank, and the 

intertank area between them. The ET holds 143,351 gallons of liquid oxygen at minus 297 

degrees Fahrenheit and 385,265 gallons of liquid hydrogen at minus 423 degrees Fahrenheit. 

scheduled for use on 

anomalies wi

tank forced the 

ET-120, the External 

Tank originally 

STS-114, arrives at 

the Kennedy Space 

Center. Various 

th this 

program to switch to 

ET-121, the tank 

originally scheduled 

for STS-121. 

Page 31 of 216 
Final Report of the Return to Flight Task Group 

A bipod ramp like the 

one shown here was 

the debris that 

doomed Columbia 

on her last flight. 

These ramps have 

been completely 

eliminated from 

the modified 

External Tanks. 

Several different types of foam insulating material are applied to the ET. The acreage foam 

that covers the majority of the ET prevents the formation of ice as moist ambient air comes in 

contact with the aluminum skin of the ET when it is filled with cryogenic propellants. Other 

types of foam and lightweight ablator materials are designed to protect the External Tank 

from aerodynamic heating as the vehicle accelerates during ascent. The ET was designed to 

be economical to produce since it is the only “throw away” portion of the otherwise reusable 

Space Shuttle. The construction techniques chosen – both for economy and to minimize 

weight – made it infeasible to use an internal insulation instead of the acreage foam. 

NASA maintains that foam remains the only viable technical solution for providing a 

lightweight, efficient, external thermal protection system. However, foam poses a variety of 

manufacturing challenges. For example, it is subject to small voids during application, 

especially around complex geometries such as joints or protrusions. This problem is 

exacerbated by the fact that foam for complicated areas must be manually applied, instead of 

the more consistent automated process that is used for the smooth areas. Using nondestructive inspection to find inconsistencies or defects in the foam is an engineering 

challenge that has eluded a reliable technical solution. NASA has conducted several searches 

for non-destructive inspection techniques in industry and research institutions and has made 

repeated attempts to develop a method of inspecting the foam for correct application; to date 

these have only been partially successful. As an alternative to inspection, NASA has 

incorporated strict process controls for both automated and manual foam applications. 

The accident board found that foam loss had occurred on more than 80 percent of the 79 

missions for which imagery was available, and foam was lost from the left bipod ramp on 

nearly 10 percent of the 72 missions where the left bipod ramp was visible following ET 

separation. It was foam debris from the left bipod ramp that caused the Columbia accident. 

For about 30 percent of all missions, there was no way to determine if foam was lost; these 

were either night launches, or the External Tank bipod ramp areas were not in view when the 

images were taken. The ET was not designed to be recovered after separation, depriving 

NASA of physical evidence that could help pinpoint why foam separates from it. Photography 

of the ET after separation – although routinely accomplished – was not a priority for the 

Space Shuttle Program prior to the Columbia accident. 

A complete description of the External Tank and this problem, as explained by the accident 

board, may be found in the CAIB final report, Volume I, Section 3.2. 

3.1.2.1 ET Debris Sources 

During the early 1990s, NASA attributed several instances of foam loss to de-bonds or voids 

in the “two-tone foam” bond layer on the intertank area forward of the bipod ramp. It was 

thought that when the intertank foam was liberated, it peeled portions of the bipod ramp off 

with it. Corrective action taken after STS-50 in June 1992 included the implementation of a 

two-gun spray technique in the ET bipod ramp area to eliminate the two-tone foam 

configuration. This appeared to have solved the problem until the sixth bipod ramp event occurred during STS-112 on October 7, 2002, two flights prior to STS-107. 

After the STS-112 bipod ramp foam loss event, 

the ET Project began developing concepts to 

redesign the bipod ramp; this activity was still 

under way at the time of the STS-107 accident. 

The dissection of bipod ramps conducted for the 

Columbia accident investigation indicated that 

defects resulting from a manual foam spray 

operation over an extremely complex geometry 

could produce foam loss. 

Page 32 of 216 
Final Report of the Return to Flight Task Group 

NASA evaluated 16 

is 

shedding. Eventually 

ice debris at the LO2 

)

selected for 

improvement or 

their likelihood to 

liberate critical 

debris. 

areas of the ET 

thermal protection 

system for debr

five areas of foam 

(numbers 5, 6, 8, 10, 

13) plus a source of 

feedline bellows (not 

shown were 

redesign based on 

The LO2 and LH2 PAL (protuberance air load) ramps are designed to reduce adverse 

aerodynamic loading on the ET cable trays and pressurization lines. PAL ramp foam loss was 

observed on two flights, STS-4 and STS-7. The most likely cause of these losses were earlier 

repairs and cryo-pumping (air ingestion) into the super-lightweight ablator (SLA) panels 

under and adjacent to the PAL ramps. Configuration changes and repair criteria were revised 

early in the program, to mitigate recurrence of these failures. The PAL ramps are large, thick, 

manually sprayed foam areas that use a less complex spray process than that used on the 

bipod; however, if liberated the ramps could become large debris. 

Another area of special interest was the intertank that separates the LO2 tank from the LH2 

tank. The area where the intertank connects to the pressurized hydrogen tank is called the 

LH2/intertank flange. Imagery taken after ET separation showed repeated loss of foam from 

this flange area prior to STS-107. 

Further investigation showed that another potential source of debris was the LO2 feedline, a 

large external pipe that runs the length of the External Tank. Bellows are located at three 

joints along the feedline to accommodate thermal expansion and contraction. The bellows 

shields are covered with foam, but the ends are exposed. Because of the cryogenic fluids in 

the pipe, ice and frost form when moisture in the air contacts the cold surface of the exposed 

bellows as well as on five brackets that hold the feedline to the ET. 

Space Shuttle Program requirements included provisions for ice on the feedline bellows, 

brackets, and adjacent lines. However, ice in these areas is a potential source of debris in the 

critical debris zone – the area from which liberated debris could impact the Orbiter. Ice has 

been seen on all missions, and after a review of flight history, NASA believes a portion of the 

historical debris damage was the result of ice impacts. 

It should be noted that, despite extensive analysis and tests, to date, neither the CAIB nor 

NASA have been able to absolutely determine the root cause for the loss of the bipod ramp 

foam during the last flight of Columbia. Additionally, the accident board also was not able to 

determine that the SRB bolt catchers, while an unlikely cause, could be definitively excluded 

as a potential cause of the left wing damage on Columbia. 

3.1.3 NASA Implementation 

After the Columbia accident, NASA initiated a three-phase approach to eliminate the potential 

for debris shedding – such as ice and foam – from the External Tank. Phase 1 included those 

Page 33 of 216 
Final Report of the Return to Flight Task Group 

activities completed prior to the return-to-flight that would control critical debris on tanks 

already constructed. NASA determined that the Phase 2 activities were not required for return 

to flight, but rather focused on continuous improvement including debris elimination 

enhancements that could be incorporated into the ET production line for new tanks. Phase 3 

would have examined additional means of further reducing ET debris potential; however, 

NASA does not plan to implement Phase 3 since the Space Shuttle is scheduled to be retired 

at the end of the decade. 

NASA made several 

debris during ascent. 

Although all are 

considered 

successful

shed critical debris. 

modifications to the 

External Tank to 

reduce foam and ice 

, testing 

and analysis show 

that the ET can still 

As part of the Phase 1 effort for return to flight, NASA modified the areas of known critical 

debris sources, although NASA has never determined the root cause for all instances of foam 

shedding. This included redesigning the forward bipod fitting and associated thermal 

protection system closeout, redesigning the LH2/intertank flange thermal protection system 

closeout, and reducing ice formation on the LO2 feedline bellows. ET intertank venting was 

increased to reduce popcorning masses in the ET foam. 

In addition to addressing these known areas of debris, NASA has reassessed all areas of the 

ET to verify the robustness of the thermal protection system configuration, including both 

automated and manual spray applications. Special consideration was given to the LO2 and 

LH2 PAL ramps due to size and location. Although there is no significant history of foam 

liberation from the longeron area, the ET Project took the conservative path of removing and 

reapplying part of this area with an improved foam application process. 

NASA also pursued a testing program to understand the root causes of foam shedding from 

various areas (with varying degrees of success) and developed alternative design solutions to 

reduce the debris loss potential. Additionally, NASA is continuing the development of two 

non-destructive inspection techniques – tetrahertz imaging and backscatter radiography – to 

conduct ET thermal protection system inspection without damaging the fragile insulating 

foam. During Phase 1, non-destructive inspection was used on the LO2 and LH2 PAL ramps 

as engineering information only; certification of the foam was achieved primarily through 

verifying the application and design. 

The bipod fitting design, fitting closeout, and heater system were reviewed during the ET 

Design Certification Review. The verification included thermal tests to determine the 

Page 34 of 216 
Final Report of the Return to Flight Task Group 

capability of the design to preclude prelaunch ice, with an automated heater control baselined 

and validated based on bipod web temperature measurements. Structural verification tests 

have confirmed the performance of the modified fitting in simulated flight environments. 

Wind tunnel testing has verified the thermal protection system closeout performance when 

exposed to the expected ascent aerodynamic and thermal environments. 

The most visible 

change to the 

External Tank was 

the elimination of the 

point and the 

installation of 

the loss of . 

bipod ramps on the 

forward ET attach 

heaters in the same 

area. The loss of one 

of these foam ramps 

was responsible for 

Columbia

Initially, NASA selected a “drip lip” to reduce ice formation on the three LO2 feedline 

bellows. The drip lip diverts condensate from the bellows and significantly reduces ice 

formation. However, since the drip lip alone was not sufficient to completely eliminate the 

ice, NASA continued to pursue complementary solutions. By April 2005, analysis of the ice 

formation, estimates of the liberated ice, and transport analyses identified the residual ice at 

the forward LO2 feedline bellows location as an unacceptable debris source; therefore, 

additional reduction of ice at the forward location was required before return to flight and 

resulted in moving the launch date from May 2005 to July 2005. 

accumulation on the 

problem. 

Three photos 

showing ice 

forward LO2 feedline 

bellows. The drip lip 

was initially chosen 

for return to flight, 

but ultimately the 

heater was installed 

to further mitigate the 

During the delay, NASA installed a heater in the forward LO2 bellows cavity to reduce ice 

formation to an acceptable level. Bonding of the heaters required removal and replacement of 

a 3-inch wide strip of foam along the existing drip lip and LO2 feedline surface. The heater 

has been installed in the tanks that will be used for STS-114, STS-121, and all future flights. 

No modifications other than the drip lips have been implemented for the mid and aft bellows 

for STS-114; NASA continues to assess other ice mitigation techniques for these locations for 

future flights. 

Page 35 of 216 
Final Report of the Return to Flight Task Group 

heater installation. 

installed at the 

Michoud Assembly 

post- ET 

and 121). 

Details of the bellows 

This heater was 

Facility on the third 

Columbia

(ET-119), but was 

retrofitted at the 

Kennedy Space 

Center on the first 

two tanks (ET-120 

The new three-step 

enhanced closeout 

process for the LH2 

intertank area. 

NASA determined the primary root cause of foam loss in the intertank/LH2 tank flange area 

was the gaseous nitrogen used as a safety purge in the intertank coming into contact with the 

extremely cold hydrogen tank dome and condensing into liquid. The liquid nitrogen migrated 

through intertank joints, fasteners, vent paths, and other penetrations into the foam and then 

filled voids in the foam caused by variability in the manual foam application. During ascent, 

the LN2 returned to a gaseous state, pressurizing the voids and causing the foam to detach. 

With this knowledge, NASA evaluated the LH2/intertank closeout design to minimize foam 

voids and nitrogen leakage from the intertank into the foam. 

The solution ultimately chosen for this area was replacement of the existing intertank closeout 

with a three-step enhanced closeout process. NASA is relying on the enhanced process in the 

LH2 intertank area to reduce the presence of defects within the foam to reduce or eliminate 

void formations in the area of the flange joining the LH2 tank to the intertank. 

Because NASA believed the PAL ramps had a satisfactory flight history and there was no 

evidence of foam loss since the last configuration change after STS-7, the baseline approach 

for return to flight was to develop sufficient certification data to accept the minimal debris 

risk of the existing design. However, a portion of the LH2 PAL ramp spans the high-risk LH2 

Page 36 of 216 
Final Report of the Return to Flight Task Group 

flange closeout. The forward 10 feet of the 38-foot-long LH2 PAL ramp was removed to 

access the underlying intertank/LH2 tank flange closeout and then replaced using an 

improved manual spray application process. 

Changes were also implemented on the intertank thrust panels to increase venting to reduce 

foam loss from “popcorning” and additional changes to the aft longeron were made to reduce 

likelihood of foam cracks and ice balls. 

The improved processes developed for the manual application of foam on the ET were used in 

limited areas of the External Tanks slated for STS-114 and STS-121 because those tanks had 

been completed prior to the Columbia accident. The use of these improved processes will be 

expanded on future tanks depending on how far through the manufacturing process those 

tanks had progressed prior to the introduction of the processes. 

Since the Phase 2 and Phase 3 efforts are not directly related to STS-114, they are not covered 

here. Details of these efforts may be found in the NASA Implementation Plan. 

Improved non-destructive inspection capabilities will provide greater knowledge of the 

condition of the External Tank foam in critical areas and the integrity of the Orbiter RCC 

prior to launch. Although an improvement, these capabilities use the best available technology 

to provide a view of what is beneath the surface, but will not allow NASA to verify the 

precise condition of foam. NASA has elected to accept the risk associated with the limitations 

of the available non-destructive inspection capabilities. 

NASA intended to use a “lead tank/trail tank” approach to support the return to flight 

activities, with the trail tank (ET-121, intended for STS-121) or a launch-on-need rescue 

mission) not shipping until after the final Design Certification Review (DCR). Because the 

final DCR was rescheduled after the required ship date for the trail ET, the Space Shuttle 

Program reassessed the risk of shipping the trail ET after the DCR versus the risk of shipping 

prior to DCR to protect the capability for a rescue mission (STS-300). Since the ET DCR PreBoard on February 23-25, 2005 did not disclose any issues that would prevent shipping the 

trail tank, the program decided the approach with the least total risk was to ship the trail ET 

on March 5, prior to the first ET DCR Board on March 8, 2005. 

NASA acknowledges that the elimination of all critical debris is not attainable, and has 

analyzed and formally accepted the remaining risk as a condition for the return-to-flight. 

Additional information on this risk analysis can be found in Section 3.3 (R3.3-2). 

3.1.4 RTF TG Assessment 

For two days beginning on September 30, 2003, several members attended a series of 

informal one-on-one meetings with members of the ET Project at the Michoud Assembly 

Facility. Numerous fact-finding activities were held at a variety of locations throughout 2004. 

Subsequently, the RTF TG attended the External Tank DCR Pre-Board on February 24-25, 

2005 and the ET Program DCR on March 8-9, 2005. The Task Group also attended the 

second ET DCR on June 20, 2005 that addressed the addition of the feedline bellows heater. 

To their credit, the External Tank DCRs were accomplished in a traditional manner, including 

formal data packages, screening of discrepancies, pre-boards, and formal boards. The two 

most significant issues for the DCR Board in March 2005 were pertaining to the verification 

of “use as-is” foam insulation on ET-120 (for STS-114) and ET-121 (for STS-121), and the 

limited amount of data from formal certification testing. The approach taken for the use as-is 

foam was to “verify by similarity” using data from the dissection of ET-94 (the thermal 

protection system on ET-94 was carefully examined by removing parts of it during the 

accident investigation). The ET Project documented all exceptions to the verification process 

Page 37 of 216 
Final Report of the Return to Flight Task Group 

in a new document, NSTS 60555, Verification Limitations for the External Tank Thermal 

Protection System, instead of processing individual waivers. 

As observed during the fact-finding, the ET Project conducted an extensive effort to 

understand the root causes of foam and ice debris generation, and this has resulted in new 

knowledge about foam and ice and what causes them to be shed from the tank during ascent. 

The ET Project determined that the most likely cause of debris generation was the 

“adhesive/cohesive” failure mode and used this as their basis of acceptance based on observed 

subsurface void size. Other failure modes, including “knit line failure” and “surface/kissing 

debonds” in acreage areas, were not addressed through design or process modifications. These 

additional failure modes offer a potential for the production of debris, although flight history 

has indicated that this debris production has not been previously observed. The processes for 

manual application of foam insulation have been changed to include greater process control 

and quality inspection. The Task Group notes that investigations into ice formation came very 

late during the return-to-flight effort due to the amount of time spent evaluating foam. 

The ET Project implemented an aggressive program to eliminate critical foam and ice debris 

and met the initial debris-allowable requirements allocated to them by the Space Shuttle 

Program. Even so, the debris-allowable requirements provided to the ET Project did not 

match what was later determined to be the impact tolerance of the Orbiter. Thus, in spite of a 

great deal of excellent work on the part of the Agency and its contractors, the External Tank 

can still shed debris that could potentially result in critical damage to the Orbiter. It should be 

noted that the potential to liberate critical debris has been significantly reduced. 

In the final analysis, the Task Group believes that the ET Project worked diligently and 

successfully met the requirements they were provided; unfortunately, those requirements were 

later determined to be inadequate. Updated requirements have been delayed mainly because 

the development of debris models and transport analysis has been hampered by a lack of rigor 

in both development and testing. However, as discussed in Section 3.3 (R3.3-2), the Space 

Shuttle Program has developed an accepted-risk rationale for the return to flight which was 

approved by program and agency leadership. 

The RTF TG assessment of NASA’s actions was completed at the June 27, 2005 meeting. The 

intent of CAIB Recommendation 3.2-1 has not been met. 

3.1.5 RTF TG Observation 

Although the Space Shuttle Program has performed an extensive effort to reduce debris for 

return to flight, there still is the potential – although reduced – for foam and ice to cause 

critical damage to the Orbiter. 

The Task Group believes that the Space Shuttle Program should continue their program 

to eliminate critical debris by aggressively working off the limitations documented in 

NSTS 60555, Verification Limitations for the External Tank Thermal Protection System. 

The Task Group also notes that the processes for manual application of foam insulation on the 

ET have changed to include greater process control and quality inspection. These processes 

are costly, but the Task Group feels that these processes should be maintained over time. 

3.1.6 RTF TG Minority Opinion 

The ET Project and Space Shuttle Program have initiated an aggressive program to eliminate 

ET debris and, within the exceptions and limitations as documented in NSTS 60555, 

Verification Limitations for the External Tank Thermal Protection System, and the Technical 

Panel believes that NASA met the intent of CAIB recommendation 3.2-1. 

Page 38 of 216 
Final Report of the Return to Flight Task Group 

3.2 CAIB Recommendation 3.3-1 – 

Reinforced Carbon-Carbon Non-Destructive Inspection 

Develop and implement a comprehensive inspection plan to determine the structural integrity 

of all Reinforced Carbon-Carbon system components. This inspection plan should take 

advantage of advanced non-destructive inspection technology. 

3.2.1 RTF TG Interpretation 

Rebaseline the reinforced carbon-carbon components by recycling through the original 

inspection process, and also using advanced technology as appropriate. 

3.2.2 Background 

The Columbia accident clearly demonstrated that the Orbiter Thermal Protection System, 

including the reinforced carbon-carbon (RCC) panels and acreage tiles, was vulnerable to 

impact damage from the existing debris environment. As a result, the Columbia Accident 

Investigation Board (CAIB) issued recommendations to eliminate debris (R3.2-1), determine 

the structural integrity of the RCC (R3.3-1), harden the Orbiter (R3.3-2) against impacts, and 

to develop on-orbit repair capabilities (R6.4-1) 

An advanced composite called reinforced carbon-carbon (RCC) is used on the Orbiter wing 

leading edge, nosecap, chin panel, and forward ET attach point. RCC is a graphite-impregnated rayon fabric laminate, further impregnated with phenolic resin and layered, one ply at a 

time, in a unique mold for each part, then cured, rough-trimmed, drilled, and inspected. The 

part is then packed in calcined coke and fired in a furnace to convert it to carbon and is made 

denser by three cycles of furfuryl alcohol vacuum impregnation and firing. 

To mitigate oxidation, the outer layers of the carbon substrate are converted into a 0.02-to0.04-inch-thick layer of silicon carbide in a chamber filled with argon at temperatures up to 

3,000 degrees Fahrenheit. As the silicon carbide cools, “craze cracks” form because the 

thermal expansion rates of the silicon carbide and the carbon substrate differ. The part is then 

repeatedly vacuum-impregnated with tetraethyl orthosilicate to fill the pores in the substrate, 

and the craze cracks are filled with a sealant. 

There are four areas 

of each Orbiter 

protected by RCC – 

the nosecap, the 

wing leading edges, 

chin panel, and the 

forward ET attach 

point. Damage to 

one RCC panel on 

the wing leading 

edge led to the 

destruction of 

Columbia. 

Page 39 of 216 
Final Report of the Return to Flight Task Group 

The development of RCC by Ling-Temco-Vought (now Lockheed Martin Missiles and Fire 

Control) was key to meeting the wing leading edge requirements for the Orbiter Thermal 

Protection System. Each wing leading edge consists of 22 RCC panels, numbered from 1 to 

22 moving outward on the wing (the nomenclature is “5-left” or “5-right” to differentiate, for 

example, the two number 5 panels). Because the shape of the wing changes from inboard to 

outboard, each panel is unique. 

The rate of oxidation is the most important variable in determining the mission life of RCC 

components. Oxidation of the carbon substrate results when oxygen penetrates the 

microscopic pores or fissures of the silicon carbide protective coating. The subsequent loss of 

mass due to oxidation reduces the load the structure can carry and is the basis for establishing 

a mission life limit. The oxidation rate is a function of temperature, pressure, time, and the 

type of heating. Repeated exposure to the Orbiter’s normal flight environment degrades the 

protective coating and accelerates the loss of mass. Currently, the mass loss of flown RCC 

components cannot be directly measured. Instead, mass loss is predicted analytically using a 

methodology based on rates experimentally derived from simulated entry environments. This 

approach then uses derived entry temperature-time profiles of various portions of RCC 

components to estimate the actual entry mass loss. 

The accident board determined that the on-vehicle inspection techniques in use at the time of 

the Columbia accident were inadequate to assess the structural integrity of the RCC 

components and attachment hardware. There were two aspects to the problem: (1) how NASA 

assessed the structural integrity of RCC components and attach hardware throughout their 

service life, and (2) how NASA verified that the flight-to-flight RCC mass loss caused by 

aging did not exceed established criteria. Structural integrity was thought to be ensured by 

wide design margins, and at the time, comprehensive non-destructive inspection was 

conducted only when the component was manufactured. Mass loss was monitored through a 

destructive test program that periodically sacrificed flown RCC panels to verify that the actual 

material properties of the panels were within the predictions of the mission life model. 

3.2.3 NASA Implementation 

After the Columbia accident, the Space Shuttle Program conducted an initial assessment of 

commercially-available equipment capable of verifying the structural integrity of RCC 

hardware while it is on the vehicle. A technical interchange meeting held in May 2003 

included experts from across the country. A variety of non-destructive inspection technologies 

with potential for near-term operational deployment were presented to the Program 

Requirements Control Board (PRCB) in January 2004: (1) flash thermography, (2) ultrasound 

(wet and dry), (3) advanced eddy current, (4) shearography, and (5) radiography. 

Thermography, contact ultrasonics, eddy current, and radiography were selected as the most 

promising techniques that could be developed in less than 12 months to be used for on-vehicle 

inspection. The PRCB approved the budget for the development of these techniques. 

Ultimately, contact ultrasonics was deemed less promising than the other techniques and its 

development was discontinued. The remaining techniques will continue to be developed and 

fielded at the Kennedy Space Center. The data they produce will complement and enhance the 

protection against abnormal flight and processing damage offered by current inspections. 

The normal RCC post-flight inspection requirements now consist of visual, tactile, and 

infrared thermography on the installed (i.e., in-situ) RCC components (wing leading edge 

panels, nosecap, and chin panel). Contingency inspections (eddy current, ultrasonic, 

radiography) will be performed if there are any suspicions of impact damage to the RCC by 

virtue of instrumentation, photographic, thermography, or visual post-flight inspection. 

RCC structural integrity and mass loss estimates were validated by off-vehicle nondestructive inspection of RCC components and destructive testing of flown wing leading edge 

Page 40 of 216 
Final Report of the Return to Flight Task Group 

panels. All wing leading edge panels, seals, nosecaps, and chin panels were removed from 

Discovery, Atlantis, and Endeavour and returned to the Lockheed Martin facility in Dallas, 

Texas, for comprehensive non-destructive inspection. Inspections included a mix of 

ultrasonic, X-ray, and eddy current techniques. In addition, NASA has introduced off-vehicle 

flash thermography for all wing leading edge panels and accessible nosecap and chin panel 

surfaces; any questionable components are subjected to a CAT scan. This data will be used to 

support development of future in-situ non-destructive inspection techniques. 

In addition, three flown RCC panels with 15, 19, and 27 missions, respectively, have been 

destructively tested to determine actual loss of strength due to oxidation. The testing of this 

flown hardware to date confirms the conservativeness of the RCC material values used for 

design and projected mission life. 

The RCC Problem Resolution Team was also given approval for a plan to evaluate attach 

hardware through non-destructive inspection and destructive testing. Detailed hardware nondestructive inspection (dye penetrant, eddy current) to address environmental degradation 

(corrosion and embrittlement) and fatigue damage concerns have been performed on selected 

OV-103/104 WLE panels in the high heat and fatigue areas. No degradation or fatigue 

damage concerns were found. 

3.2.4 RTF TG Assessment 

Members of the RTF TG conducted fact-finding at the Kennedy Space Center on September 

24, 2003. NASA submitted a closure package on April 7, 2004, and sufficient progress had 

been made for the Task Group to conditionally close this assessment at the April 16, 2004, 

public meeting. There were four conditions on the closure: an updated version of the 

Operations and Maintenance Requirements and Specifications Document, File 3, Volume 9, 

to include the inspection of the RCC panels, the closure of all Material Review and Problem 

Reports from the Discovery and Atlantis RCC non-destructive inspections, the receipt of 

PRCB Directive S064002 closing the NASA review of non-destructive inspection techniques, 

and the closure of the remaining RTG TG requests for information regarding impact test data. 

Jim Landy, a 

specialist with United 

Space Alliance, 

examines a wing 

leading edge 

reinforced carboncarbon panel using 

flash thermography. 

A relatively new 

procedure at KSC, 

thermography uses 

high intensity light to 

heat areas of the 

panels. The panels 

are then immediately 

scanned with an 

infrared camera. As 

the panels cool, any 

internal flaws are 

revealed. 

Page 41 of 216 
Final Report of the Return to Flight Task Group 

As of December 2004, the RTF TG had received two of the items required for closure; the 

PRCB Directive and the RCC impact test data. The Operations and Maintenance 

Requirements and Specifications Document updated for inspection of RCC panels and closure 

packages for all MR/PRs from detailed RCC non-destructive inspection were delivered on 

February 2, 2005. 

One other item of concern to the Task Group, an anomaly discovered in the nosecap from 

Endeavour, was satisfactorily explained by NASA. The damage occurred during a sealant 

refurbishment process; other RCC had previously been subjected to the same process without 

incident. It was concluded that the nosecap had a latent manufacturing flaw and was not cause 

for concern about any of the RCC on Discovery. 

The RTF TG assessment of NASA’s actions was completed at the February 17, 2005 

teleconference meeting. The intent of CAIB Recommendation 3.3-1 has been met. 

3.2.5 RTF TG Observation 

The Task Group stresses that these inspections only verified the RCC against its original “asbuilt” manufacturing specifications and did not materially change the RCC or its impact 

resistance; this recommendation did not call for any change to the material. The original 

manufacturing specifications for RCC never envisioned the need for repair, nor were they 

written with the knowledge of the actual debris environment. This makes the elimination of 

debris shedding (R3.2-1) and Orbiter hardening (R3.3-2) all the more important. The Task 

Group also strongly endorses the continuation of non-destructive inspections of the RCC for 

the remainder of the Space Shuttle Program, the documentation of flight-to-flight inspections 

in the OMRSD, and the documentation of non-destructive inspection standards for RCC. 

shop mechanic with 

United Space 

installation of a 

wi

Note the insulation 

panel and the 

g sp

Billy Witt, a midbody 

Alliance, checks a 

part used for 

reinforced carboncarbon panel to the 

leading edge of the 

ng of an Orbiter. 

between the RCC 

win ar. 

Page 42 of 216 
Final Report of the Return to Flight Task Group 

3.3 CAIB Recommendation 3.3-2 – 

Orbiter Hardening 

Initiate a program designed to increase the Orbiter’s ability to sustain minor debris damage 

by measures such as improved impact-resistant Reinforced Carbon-Carbon and acreage tiles. 

This program should determine the actual impact resistance of current materials and the 

effect of likely debris strikes. 

3.3.1 RTF TG Interpretation 

Develop a detailed plan for an Orbiter hardening program including testing and modeling to 

determine the impact resistance of the Thermal Protection System. For the first Orbiter 

returning to flight, the actual impact resistance of installed material and the effect of likely 

debris strikes should be known. Implement hardware changes as defined in the hardening 

program. 

3.3.2 Background 

The Columbia accident clearly demonstrated that the Orbiter Thermal Protection System, 

including the reinforced carbon-carbon (RCC) panels and acreage tiles, was vulnerable to 

impact damage from the existing debris environment. As a result, the Columbia Accident 

Investigation Board (CAIB) issued recommendations to eliminate debris (R3.2-1), determine 

the structural integrity of the RCC (R3.3-1), harden the Orbiter (R3.3-2) against impacts, and 

to develop on-orbit repair capabilities (R6.4-1). 

The development of RCC by Ling-Temco-Vought (now Lockheed Martin Missiles and Fire 

Control) was key to meeting the wing leading edge requirements for the Orbiter Thermal 

Protection System. Each wing leading edge consists of 22 RCC panels, numbered from 1 to 

22 moving outward on the wing (the nomenclature is “5-left” or “5-right” to differentiate, for 

example, the two number 5 panels). Because the shape of the wing changes from inboard to 

outboard, each panel is unique. 

It had always been known that the impact resistance of the acreage tiles that cover the 

majority of the Orbiter was limited, but flight experience indicated the tiles could tolerate 

some damage. The reinforced carbon-carbon used on the nose and wing leading edges was 

thought to have better impact resistance and damage tolerance. The Columbia accident and 

subsequent testing revealed that the impact tolerances for both RCC and acreage tiles were 

lower than believed. In addition, careful examination of flight data revealed that the debris 

environment was somewhat worse than had been thought, with both foam and ice from the 

External Tank frequently impacting the Orbiter during ascent. 

3.3.3 NASA Implementation 

NASA selected 17 hardening options to be implemented in three phases. Based primarily on 

maturity and schedule, four projects were identified as Phase I options for implementation 

before return to flight: front spar “sneak flow” protection for the most vulnerable and critical 

RCC panels 5 through 13; main landing gear corner void elimination; forward Reaction 

Control System carrier panel redesign to eliminate bonded studs; and installing thicker outer 

thermal panes in side windows 1 and 6. 

NASA also selected two Phase II options for implementation after return to flight: “sneak 

flow” front spar protection for the remaining RCC panels 1 through 4 and 14 through 22, and 

the main landing gear door perimeter tile material change. Both of these Phase II projects are 

in the final design phase and will be executed during Orbiter Major Modification periods or 

during extended between-mission flows. 

Page 43 of 216 
Windows installed on OV-103 and OV-104/final cert

approval pending

Thicken Windows #1 and #6 I

III

III

III

III

III

III

I

III

III

II

I

III

III

III

II

I

“Sneak Flow” Front Spar Protection (RCC #1 – 4, 4 - 22) Final cert approval pending

This option will be eliminated since it only

increases the Orbiter’s capability in the event of an

abort during ascent. Trajectory can be designed to

minimize vertical tail temperature.

Development complete/ authorization pending for

qual & cert

In Assessment/lower priority to RTF

On-hold until post RTF

Qual & Cert in work

Qual & Cert in work. BRI 18 tile has been

authorized for installation on all three Orbiters

Installed/ final cert approval pending

In Assessment/lower priority to RTF

In Assessment/lower priority to RTF

In Final Design phase

Installed/final cert approval pending

Schedule and cost of implementing this option is

not in sych with Agency’s vision to retire Shuttle in

2010

On hold for higher priority arc-jet testing

BRI-18 tile continues to be in qual & cert

Installed/final cert approval pending

Lower Access Panel Redesign/BRI 18 Tile Implementation

Vertical Tail AFSI High Emittance Coating

Tougher Upper Surface Tiles.

Elevon Leading Edge Carrier Panel Redesign

TPS Instrumentation

Tougher Acreage (BRI 8) Tiles and Ballistics SIP on Lower

Surface.

Tougher Periphery (BRI 18) Tiles around MLGD, NLGD, ETD,

Window Frames, Elevon Leading Edge and Wing Trailing Edge.

Forward RCS Carrier Panel Redesign – Bonded Stud Elimination 

External Tank Door Thermal Barrier Redesign

Nose Landing Gear Door Thermal Barrier Material Change

Main Landing Gear Door Perimeter Tile Material Change

Main Landing Gear Door Corner Void

Robust RCC 

Insulator Redesign

“Sneak Flow” Front Spar Protection (RCC #5 – 13)

Final Report of the Return to Flight Task Group 

Since the Phase II and Phase III efforts are not directly related to the return to flight of 

STS-114, they are not covered in any more detail in this report. Further details of these 

efforts may be found in the NASA Implementation Plan. 

The 17 projects 

examined for Orbiter 

hardening, along 

with the associated 

phase for each and 

its status when this 

assessment was 

made. 

Family Redesign Proposal Phase Status

WLESS “Sneak Flow ” Front Spar Protection (RCC #5 – 13) I Installed/final cert approval pending 

“Sneak Flow” Front Spar Protection (RCC #1 – 4, 4 - 22) II Final cert approval pending 

Low er Access Panel Redesign/BRI 18 Tile Implementation III BRI-18 tile continues to be in qual & cert 

Insulator Redesign III On hold for higher priority arc-jet testing 

Robust RCC III Schedule and cost of implementing this option is 

not in sych with Agency’s vision to retire Shuttle in 

2010 

Landing Gear Landing Gear 

and ET Door and ET Door

Main Landing Gear Door Corner Void I Installed/final cert approval pending 

Thermal Barriers Main Landing Gear Door Perimeter Tile Material Change II In Final Design phase 

Nose Landing Gear Door Thermal Barrier Material Change III In Assessment/lower priority to RTF 

External Tank Door Thermal Barrier Redesign III In Assessment/lower priority to RTF 

Vehicle Carrier

Panels – Bonded s – Bonded 

Stud Elimination

Forw ard RCS Carrier Panel Redesign – Bonded Stud Elimination I Installed/ final cert approval pending 

Side Window s de Windows Thicken Windows #1 and #6 I Window s installed on OV-103 and OV-104/final cert 

approval pending 

Tougher Low er Tougher Lower

Surface Tiles

Tougher Periphery (BRI 18) Tiles around MLGD, NLGD, ET D, 

Window Frames, Elevon Leading Edge and Wing T railing Edge. 

III Qual & Cert in w ork. BRI 18 tile has been 

authorized for installation on all three Orbiters 

Tougher Acreage (BRI 8) T iles and Ballistics SIP on Low er 

Surface. 

III Qual & Cert in work 

Instrumentation TPS Instrumentation III On-hold until post RTF 

Elevon Cove Elevon Leading Edge Carrier Panel Redesign III In Assessment/lower priority to RTF 

Tougher Upper

Surface Tiles

Tougher Upper Surface T iles. III Development complete/ authorization pending for 

qual & cert 

Vertical Tail Vertical Tail AFSI High Emittance Coating III This option w ill be eliminated since it only

increases the Orbiter’s capability in the event of an 

abort during ascent. Trajectory can be designed to 

minimize vertical tail temperature. 

Existing New design 

New Thicker

 Pane 

HRSI Tiles 

OML 

New Thicker 

Inner Retainer 

Additional 

Thickness 

0.3” 

T=.86 

TYPICAL SIDE (1&6) WINDOW CROSS SECTION 

T=.56 

0.1” 

Window Retainer 

Structure 

The new outer 

thermal panes 

installed in windows 

1 and 6 are 0.30-

inch thicker than the 

original panes. This 

necessitated 

changing the 

Thermal Protection 

System tiles 

surrounding the 

windows. 

3.3.3.1 Impact and Damage Tolerance 

Using both test and analysis, the Orbiter Damage Impact Assessment Team determined the 

impact and damage tolerance of tile, RCC, and the Orbiter windows to External Tank foam, 

ice, and ablator debris. Impact tolerance is the ability of the Orbiter Thermal Protection 

System materials to withstand impacts before damage occurs. Damage tolerance is defined as 

the level of damage from a debris strike that can be tolerated while still safely completing the 

mission, especially entry. 

Page 44 of 216 
0.1(M)

0.1(M) 0.3(M)

0.25

0.8(M)

0.2 (O)

0.1(O)

0.1(O)

0.5

0.1

0.1(M)*

0.2

0.15

0.4

0.1(O)

0.15(M)

0.1(M)

0.25

0.5(M&TFS)

0.6

0.1

0.3 0.1

0.25

0.35

0.3

0.25

0.25

0.15(M)

Allowable Depth of

Penetration into Tile

Region of large OOPD

0.1(O)**

0.5(M&TFS)

0.4

0.1(S&TFS)

Final Report of the Return to Flight Task Group 

Preliminary impact tolerance data was used as the basis for the ET Project’s work to certify 

the ET for foam debris generation. Subsequent test and analysis confirmed that the worst-onworst damage tolerance of the tile and RCC was less than the ET certification limit. 

REMOVABLE INSULATOR 

SPAR FITTING FRONT WING SPAR 

FLOW RESTRICTOR 

UP 

FIXED INSULATOR 

INBD 

SIP 

SIP 

LOWER ACCESS 

PANEL 

VIEW LOOKING AFT & INBOARD 

(RCC PANEL & FORWARD PARTS OMITTED ) 

3.3.3.2 Tile Impact and Damage Tolerance 

Tests to determine TPS tile impact tolerance – using foam, ice, and ablator projectiles – have 

been completed at several field centers and other test facilities using both acreage and special 

configuration tiles, and both new and aged tiles. These tests indicated that, although tile is not 

very resistant to impact, it tolerates entry heating well even with damage. Overall, testing 

shows tile to be tolerant to moderate levels of impact damage; tile damage tolerance depends 

on tile thickness among other factors, which varies by location. As a result, certain areas of 

reduced thickness, such as those tiles adjacent to the main landing gear doors, are more 

susceptible to critical damage. Based on tests and on flight history, NASA developed and 

certified zone and cavity definitions for tile with similar structural and thermal characteristics 

to determine the depth of allowable damage penetration into the tile before critical damage 

occurs and repair is necessary. These zones take into account aerodynamic heating, impact 

angle, and tile thickness, but assume rectangular damage where the length and width 

dimensions are a function of depth. 

) 

(M) ) 

(M) 

(O) 

( O) 

(O) 

)* 

(M) 

(M) 

( ) 

(M) 

(O)

) 

) 

0.1(M

0.1 0.3(M

0.25 

0. 8

0. 2

0.1

0. 1

0. 5 

0.1 

0.1(M

0.2 

0.15 

0. 4 

0.1(O) 

0.15

0.1

0.25 

0. 5 M&T FS 

0.6 

0. 1 

0.3 0. 1 

0. 25 

0.35 

0. 3 

0. 25 

0. 25 

0.15

Allowable Depth of 

Penetration into Tile 

Region of large OOPD 

0. 1 ** 

0. 5(M&T FS 

0.4 

0. 1(S&TF S

Flow restrictors and 

additional insulation 

were added behind 

wing leading edge 

RCC panels 5 

through 13; the other 

panels will receive 

similar modifications 

after the return to 

flight. 

Since the heating 

loads vary across the 

Orbiter, the amount 

of damage that can 

be tolerated also 

varies. This chart 

shows the allowable 

depth of penetration 

into areas of acreage 

tiles that has been 

certified as safely 

tolerable. The red 

outline shows the 

region of large out of 

plane deflection 

(OOPD). 

Page 45 of 216 
Final Report of the Return to Flight Task Group 

Each RCC panel 

was split into seven 

zones, and the level 

of damage that could 

be tolerated was 

evaluated for each 

zone. The zones on 

the bottom of the 

panel and the apex 

cannot tolerate any 

substantial damage 

due to the thermal 

environment these 

areas are subjected 

to during entry. 

In addition, analysis of the Space Shuttle’s flight history indicated that tile damage fell into 

three impact classes: (1) numerous, shallow impacts primarily on the forward chine and 

fuselage; (2) fewer, deeper impacts primarily on the lower surface; and (3) umbilical area 

impacts. The majority of historical damage fell into the first category, and was likely caused 

by foam popcorning rather than large foam divots; increased ET intertank venting is expected 

to reduce popcorning masses in the ET foam. The second category of damage, with fewer 

deeper impacts, was most likely the result of ice from the ET bellows and brackets and ET 

foam divots; this category of damage is the most likely to require repair. Finally, the umbilical 

area had a mixture of both small and large impacts from a unique subset of sources including 

ET umbilical ice, baggies, Kapton tape, and ET fire detection paper. Debris transport analysis 

suggests that most of the impacts came from “local” sources rather than from the forward ET. 

As a result, NASA expects little change to the damage in the umbilical area. 

3.3.3.3 RCC Impact and Damage Tolerance 

Impact and damage tolerance testing on the RCC was performed at several NASA field 

centers and other test facilities, using both RCC “coupons” (small samples of material) and 

full-scale RCC panels. It was found that RCC is impact tolerant but not damage tolerant, since 

even minor cracks or coating loss can be critical and prevent safe entry. Structural and 

thermal testing of damaged RCC samples established how much damage can be tolerated and 

still allow a safe return for the crew and vehicle. Test-verified models established impact 

tolerance thresholds for foam and ice against tile and RCC. These impact tolerance thresholds 

are the levels at which detectable damage begins to occur. 

Arc-jet testing showed that the RCC cannot tolerate any significant loss of coating from the 

front surface in areas that experience full heating on entry. This is of concern because impacts 

can create subsurface delamination of the 

RCC that is undetectable through imaging 

scans. Testing indicates that loss of frontside coating in areas that are hot enough to 

oxidize and/or promote full heating of the 

damaged substrate can cause unacceptable 

erosion damage in the delaminated areas. 

However, for subsurface delamination to be 

a concern there needs to be front-side 

damage, thus eliminating the concern of 

“hidden” damage. Further testing and 

modeling have shown that, although the 

hottest areas on the wing leading edge (the 

bottom and apex surfaces) cannot tolerate 

any significant coating loss, other cooler 

areas (such as the top surface of the wing 

leading edge) can tolerate some amount of 

coating loss and subsurface delamination. Testing and model development work has produced 

a map of the damage tolerance capabilities of the wing leading edge RCC depending on panel 

and location (top, apex, or bottom surface). 

Testing is also complete on window impact from debris, including butcher paper, ablator 

material, foam, Tyvek®, aluminum oxide, and small/fast ogive foam. NASA’s debris transport 

analysis suggests that very small ogive foam has the potential to impact the Orbiter windows, 

but impact tolerance tests indicate that the windows can withstand these impacts without 

sustaining critical damage. Testing also indicated that butcher paper – used to cover the 

forward reaction control system thrusters at the launch pad – caused unacceptable damage to 

the windows. As a result, NASA replaced butcher paper covers with Tyvek covers (similar to 

what large FedEx® envelopes are made of) that will not cause critical damage. 

Page 46 of 216 
Final Report of the Return to Flight Task Group 

3.3.3.4 Orbiter Hardening 

NASA has completed implementation of the four Phase I Orbiter hardening tasks. Beyond the 

return to flight, NASA will continue to pursue Phase II and III hardening options and will 

implement those that are feasible at the earliest possible opportunity. 

3.3.3.5 Risk Assessment 

NASA identified, categorized, and assessed all known potential debris sources in order to 

assess the risk to the vehicle of debris. Most debris sources could be determined to be no 

threat to the Orbiter either because the debris was liberated before it gained enough velocity 

and kinetic energy to damage the Orbiter, was too small to be of concern (0.0002 lbm or less), 

or the transport analysis showed there was no path to take the debris from the source to any 

Orbiter structure. This left only a handful of debris sources of concern to be scrutinized and 

assessed for the potential to liberate debris that could cause critical damage to the Orbiter. 

The program’s “worst-on-worst” analysis of three of the remaining debris sources – acreage 

foam from the LH2 tank, LO2 tank and the intertank – showed they would not shed foam that 

could cause more damage than the Orbiter could safely enter with. 

A Monte Carlo probabilistic analysis was done for five foam areas (LO2/intertank ice/frost 

ramps, LO2 tank to intertank flange, LH2 tank to intertank flange, LO2 PAL ramp, and bipod 

closeout) and four ice locations (mid and aft feedline bellows, and forward and mid feedline 

brackets). There were two independent approaches for the Monte Carlo analysis: one for foam 

debris, which used physics-based models for foam liberation, and another for ice debris, 

which had to rely on engineered distributions based on a very limited set of test data for ice 

liberation. It is the Agency’s opinion that there is a great deal of conservatism in both 

approaches, but NASA has not been able to drive out the conservatisms from the models, 

mostly due to modeling limitations, a lack of time to generate ice-specific damage maps for 

tile, and limited test data not matching flight data. Each of the resulting probabilities for 

critical damage to RCC due to foam or ice liberation is less than 1 in 10,000; for tile, the 

probabilities range from 1 in 100 to 1 in 10,000. The four highest probabilities for critical 

damage to tile are for ice from the mid feedline bellows and second feedline bracket locations, 

and foam from the LO2 ice/frost ramps and the LO2 tank to intertank flange. 

NASA determined that the residual risk to several of the remaining areas was enveloped by 

the probabilistic assessments: the LH2 ice/frost ramp foam residual risk was enveloped by the 

LO2/intertank ice/frost ramps, the LH2 PAL ramp by the LO2 PAL ramp, and the three aftmost feedline bracket locations by the forward and mid feedline brackets. The potential for ice 

on the forward feedline bellows location was greatly reduced by the addition of a heater in 

that area, and the remaining ice that could form in that location will be controlled by launch 

commit criteria, documented in NSTS 08303, Ice/Debris Inspection Criteria. 

One debris source, ice around the umbilical doors, could not be shown by any means other 

than flight history to be an acceptable risk. NASA’s rationale for accepting this risk was that 

there is no transport mechanism to RCC or the windows and flight history showed that while 

there is a moderate amount of damage on most flights in this area, none has been severe. 

3.3.4 RTF TG Assessment 

members of the RTF TG conducted the first fact-finding trip for this recommendation on 

October 28-30, 2003, a trip to Southwest Research Institute (SwRI) to witness a foam “shoot” 

against an RCC wing leading edge panel. Additional fact-finding during 2004 included 

numerous Debris Summits, and the Task Group attended the Orbiter Design Certification 

Review on February 7-11, 2005. Members of the Task Group also attended a series of System 

Page 47 of 216 
Final Report of the Return to Flight Task Group 

Design Certification Reviews and Design Verification Reviews for Debris from February 

through June, 2005, culminating in the (final) Debris DVR Board on June 24, 2005. Members 

also attended the Delta System DCR on June 23, 2005. 

This recommendation had two primary parts, Orbiter hardening and determining the impact 

resistance and the effect of likely debris strikes on the Orbiter TPS. Out of the Agency’s effort 

in the area of Orbiter hardening, a hardware program was initiated that provided some minor 

improvements that supported return to flight. The STS-114 improvements include thicker 

thermal panes for side windows 1 and 6, limited “sneak flow” front spar protection, main 

landing gear door corner void elimination, and modifications to the forward RCS carrier 

panel; additional items will be incorporated on later flights. A long-term program to provide 

robust RCC was dropped due to the decision to retire the Space Shuttle by 2010. 

The other part of this recommendation was a program to characterize the effects of debris 

strikes on the Orbiter Thermal Protection System. NASA embarked on a major effort toward 

that end. A program to determine the impact resistance of the TPS was performed and 

supported by a significant level of testing and analysis with independent peer reviews. Results 

from early testing and analysis were used to define ET debris allowable and Space Shuttle 

inspection criteria. As the testing and analysis effort matured, these early results were found 

to overestimate the impact and damage tolerances of the Orbiter TPS and a risk acceptance 

rationale had to be developed by the Space Shuttle Program. 

An extensive effort was made to model the effects of debris impacts and validate them against 

the available test data. These models will be used to assess damage sustained during flight. 

The foam assessments are reasonably well understood; however the Space Shuttle Program is 

struggling with understanding the effects of ice debris and had not finalized this effort when 

the Task Group’s assessment was completed. The NASA Engineering and Safety Center 

(NESC) stated at the June 24, 2005 Debris Verification Review Board, “Based on the 

available test data and analysis results, the NESC has concluded that the feedline brackets, 

bellows, and ET umbilical ice debris environment is not sufficiently characterized or 

understood to assign the level of risk. To establish the flight rationale for STS-114, additional 

work is required to develop adequate controls for ice.” 

The Orbiter is still vulnerable to the debris environment created by the External Tank. The 

Space Shuttle Program has acknowledged the possibility of critical debris damage and has 

accepted the remaining risk. 

The RTF TG concluded at the June 27, 2005, meeting that NASA did not meet the intent of 

CAIB Recommendation 3.3-2, in spite of tremendous effort by NASA and its contractors. 

Two reasons were cited: the present lack of a long-term approach to RCC hardening – an 

early long-term plan for Orbiter hardening was abandoned after the National Policy decision 

to retire the Space Shuttle fleet no later than 2010 – and the amount of remaining nonstandard open work on ice debris, risk analysis, and verification of damage models. 

3.3.5 RTF TG Observation 

Although the Space Shuttle Program has performed an extensive effort to reduce debris for 

return to flight, there still is the potential – although reduced – for foam and ice to cause 

critical damage to the Orbiter; NASA will need to continue to reassess their accepted risk 

rationale flight-to-flight. 

3.3.6 RTF TG Minority Opinion 

The Technical Panel believes that, with the completion of the documented open work, the 

Space Shuttle Program met the intent of the CAIB recommendation. 

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Final Report of the Return to Flight Task Group 

3.4 CAIB Recommendation 3.4-1 – 

Ground-Based Imagery 

Upgrade the imaging system to be capable of providing a minimum of three useful views of 

the Space Shuttle from liftoff to at least Solid Rocket Booster separation, along any expected 

ascent azimuth. The operational status of these assets should be included in the Launch 

Commit Criteria for future launches. Consider using ships or aircraft to provide additional 

views of the Shuttle during ascent. 

3.4.1 RTF TG Interpretation 

The Columbia post-accident investigation was hampered by the lack of high-resolution 

imagery of the vehicle during ascent. The existing ground-based camera locations were a 

legacy of earlier programs and their locations were not optimized for the ascent trajectory of 

recent Space Shuttle missions. Further, due to equipment problems and a lack of clear 

requirements to maintain this equipment, imagery was not always usable, as was the case for 

the STS-107 launch. The Columbia Accident Investigation Board (CAIB) was concerned 

about the need to have an adequate number of appropriately-located cameras that operated 

properly to provide photographic coverage from more than one view of the Space Shuttle 

from launch through separation of the Solid Rocket Boosters. 

3.4.2 Background 

Of the dozen ground-based camera sites used to obtain images of the Space Shuttle during 

ascent, five were normally used to track the vehicle from liftoff until it was out of view. Due 

to view angles and atmospheric limitations, two sites did not capture the STS-107 debris 

event. Of the remaining three sites positioned to “see” at least a portion of the event, none 

provided a clear view of the actual debris impact to the wing. The first site lost track of 

Columbia during ascent, the second site was out of focus – because of an improperly 

maintained lens – and the third site captured only a view of the upper side of the left wing. 

The CAIB noted that camera problems had also hindered the Challenger investigation 17 

years earlier. Although the initial debris strike during STS-107 was discovered via image 

analysis, NASA’s post-launch evaluation of the impact was hampered by the lack of multiple 

views from high-resolution, high-speed ground cameras. The CAIB also found the quality of 

existing imagery – of all recent Space Shuttle launches – to be less than ideal. 

1998 at SRB 

resolution limitations of 

Long-range tracking 

camera (E-207) photo 

of STS-95 in October 

separation shows the 

ground tracking. 

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Multiple views of launch and ascent from varying angles provide important data for 

engineering assessment and the detection of unexpected anomalies. Images may also be used 

to assess debris shedding in flight, including the origin, size, and trajectory of the objects. 

Because of resolution limitations, however, this imagery is not intended to pinpoint the exact 

nature of potential damage to the vehicle. Finally, in keeping with the CAIB view that the 

Space Shuttle should be treated as a developmental flight vehicle, imagery assets should be 

used to measure its performance for the duration of the Space Shuttle Program. 

3.4.3 NASA Implementation 

A suite of improved ground-based and airborne cameras has been deployed to provide the 

ability to capture three complementary views of the Space Shuttle during launch and ascent. 

This will allow a better understanding of the ascent environment and the performance of the 

vehicle within this environment. Ground imagery may also allow the detection of ascent 

debris and identify potential damage locations on the Orbiter for detailed on-orbit assessment. 

There are four types of imagery that NASA will acquire from the ground cameras: 

• Primary imagery – film images used as the primary analysis tools for launch and 

ascent operations; 

• Fall-back imagery – back-up imagery (primarily 35mm and 16mm motion 

pictures) for use when the primary imagery is unavailable; 

• Quick-look imagery – digital imagery (primarily HDTV and SDTV) provided to 

the image analysis groups shortly after launch for initial assessments; and 

• Tracker imagery – imagery used to guide the camera tracking mounts and for 

analysis when needed. 

Although ground cameras provide important engineering data for the Space Shuttle, they are 

not intended to provide the resolution to identify the exact nature of any potential damage to 

the Orbiter. No real-time repair decisions will be directly based on this ascent imagery data. 

Instead, any anomalies identified using ground-based imagery assessments will be used to 

optimize the on-orbit inspections described in Section 3.13 (Recommendation 6.4-1). 

For the STS-114 launch, NASA has three short-range camera sites around the perimeter of the 

launch pad, seven medium-range camera sites, and nine long-range camera sites. Each of the 

medium- and long-range tracking cameras is independent, ensuring that no single failure can 

disable all of the trackers. Further, each of the film cameras on the trackers has a backup (fallback), so no single camera failure eliminates a particular view. The locations of the new 

cameras and trackers are optimized for 51.6-degree-inclination launches since most, if not all, 

future Space Shuttle launches will be to the International Space Station. Previously, camera 

coverage was limited by a generic configuration originally designed for the full range of 

possible launch inclinations and ascent tracks envisioned early in the Space Shuttle program. 

Space Shuttle ascent imagery acquisition is divided into three overlapping periods with 

different requirements that provide for steps in lens focal lengths to maintain image resolution 

as the vehicle moves away from each camera location: 

• Short-range images (T-10 seconds through T+57 seconds); 

• Medium-range images (T-7 seconds through T+100 seconds); and 

• Long-range trackers (T-7 seconds or vehicle acquisition through

T+165 seconds). 

Page 50 of 216 
Final Report of the Return to Flight Task Group 

Left: Three short-range 

tracking sites are 

located around each 

LC-39 launch pad. 

NORTH 

Camera Site 1 

E53, EH53, E55 Camera Site 6 

E57, EH57, E59 

° 

Camera Site 2 

E52, EH52, E54 

NORTH 

51.6-degree 

Launch 

Azimuth 

UCS-9 

E223, 

UCS-6 EH223 

E224, 

EH224 B 

KENNEDY 

SPACE 

CENTER 

CAPE 

MERRITT 

ISLAND 

INDIAN 

RIVER 

UCS-7 

E213, 

EH213 UCS-17

E226, 

EH226 BEACH SITE 

E222, EH222 

UCS-15 

E220, ATLANTIC 

EH220 OCEAN 

Right: Medium-range 

tracking sites available 

for the Space Shuttle 

Program 

imuth 

ATLANTIC 

OCEAN 

itt 

Isl

B 

Playalinda DOAMS 

E207, EH207 

Apollo Beach 

E217, EH217 

Merr

and 

Indian 

River 

Kennedy 

Space 

Center 

UCS-11 

E215, EH215 

Shiloh 

E205, EH205 

51.6-degree 

Launch Az

Ponce Inlet NORTH 

E211, EH211 

UCS-23 

E212, EH212 

UCS-3 

E214, EH214 

Cocoa 

UCS-25 

E206, EH206 

D5R67 

E216, EH216 

Cape 

Canaveral 

Long-range tracking 

sites located around 

the Kennedy Space 

Center. 

Currently, this capability nominally consists of 7.8-, 32-, 150-, and 400-inch focal length 

lenses. The theoretical limits of the optics under ideal conditions – assuming the object is not 

obscured by the exhaust plume and depending on orientation of vehicle to plane of film – 

provide: 

• Resolution to 1-inch size and 0.5-foot linear accuracy of debris source and 

impact location from lift-off to L+30 seconds along any expected azimuth; 

• Resolution to 3-inch size and 1-foot linear accuracy of debris source and impact 

location from L+30 seconds to L+60 seconds along any expected azimuth; 

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Final Report of the Return to Flight Task Group 

• Resolution to 8-inch size and 3-foot linear accuracy of debris source and impact 

location from L+60 seconds to L+90 seconds along any expected azimuth; 

• Resolution to 15-inch size and 5-foot linear accuracy of debris source and 

impact location from L+90 seconds to SRB separation (approximately 122 miles 

from the launch site) along any expected azimuth. 

Range to target versus 

time for the two 

DOAMS long-range 

tracking sites. Only the 

Playalinda Beach 

DOAMS (E207) will be 

used for STS-114. The 

Cocoa Beach DOAMS 

(E208) is being moved 

to a new location at 

Patrick AFB and will not 

be used to support the 

first two launches. 

V )

0 

5 

10 

15 

20 

25 

30 

35 

40 

45 

50 

0 10 20 30 40 70 80 90 110 120 130 140 

(

il ) 

les) 

i

ehicle (STS-95 Range to Camera Site vs Time MET 

50 60 100 

MET Time seconds) 

Miles from Camera Site 

E208 Range (M es

E207 Range (MI

SRB Separat on 

122.396 sec MET 

These images will be acquired by a combination of mobile Kineto Tracking Mount (KTM), 

Intermediate Focal Length Optical Tracking (IFLOT), and Advanced Transportable Optical 

Tracking System (ATOTS) platforms that can be optimally positioned for each flight based on 

launch azimuth and other considerations. In addition, the fixed-position Distant Object 

Attitude Measurement System (DOAMS) site at Playalinda Beach, operated by the Air Force 

45th Space Wing, will continue to be used for long-range observation. The “fuzzy” optics in 

the Cocoa Beach DOAMS noted by the CAIB has been corrected by the vendor, but the Air 

Force is in the process of moving this fixed installation several miles south to Patrick AFB to 

avoid high-rise condominiums that have been erected adjacent to the existing site, severely 

restricting the view of the launch areas; it will not be used to support STS-114. 

tracking site. 

A DOAMS long-range 

NASA is continuing to ship 14 existing trackers at the Kennedy Space Center to the White 

Sands Missile Range for refurbishment. This work will be ongoing until refurbishment of all 

trackers is complete in 2008. Trackers and optics will be borrowed from other ranges to 

support launches until the refurbished assets are redelivered. NASA is also procuring 

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Final Report of the Return to Flight Task Group 

additional cameras to provide increased redundancy and refurbishing existing cameras. NASA 

has ordered 35 fixed camera lenses to supplement the existing inventory and has purchased 

two KTM Digital Signal Processing Amplifiers to improve KTM reliability and performance. 

In addition, NASA has received 24 HDTV cameras to improve quick-look capabilities. 

Funding has also been approved to procure additional spare mounts, as well as to fund studies 

on additional capability in the areas of infrared and ultraviolet imagery, adaptive optics, and 

high-speed digital video. 

During, and subsequent to, the accident investigation, there was considerable interest in 

whether video technology had evolved far enough to replace film as the primary imagery for 

Space Shuttle launches. The NASA Intercenter Photo Working Group (IPWG) compared the 

image resolution of several different types of image gathering systems and determined their 

theoretical maximum performance. 

Based on this analysis, NASA decided that the primary product for imagery analysis will 

continue to be film due to its resolution capability and dynamic range. The long-range 

tracking sites use 70mm cameras to track the Solid Rocket Boosters after separation and to 

provide “big sky” coverage of any major mishaps. All short- and medium-range tracking sites 

use 35mm cameras for optimum “resolution-on-media” as their primary imagery. Close-in 

fixed camera sites use high-speed (400 frames per second) 16mm film motion picture 

cameras. All short-, medium-, and long-range tracking sites use HDTV for a quick-look 

capability and as a backup to the primary 35mm or 70mm cameras. SDTV was not chosen as 

an analysis tool, but it will continue to be used by camera site operators for wide field-of-view 

target locating. SVHS demonstrated a poor resolution that made it unacceptable as an analysis 

tool, although budget constraints have forced its use in some limited instances. 

In addition to ground cameras, NASA approved the development and implementation of an 

aircraft-based imaging system known as the WB-57 Ascent Video Experiment (WAVE) to 

provide both ascent and entry imagery. 

Long-range trackers at 

the Kennedy Space 

Center. 

The two NASA 

high-altitude WB-57F 

aircraft have been 

modified with cameras 

to photograph the 

Space Shuttle during 

ascent. 

Page 53 of 216 
Final Report of the Return to Flight Task Group 

Computer model showing 

the views expected from 

the WB-57 WAVE aircraft. 

The use of an airborne imaging system will provide opportunities to better observe the vehicle 

during days of heavier cloud cover and in areas obscured from ground cameras by the exhaust 

plume following launch. The use of two aircraft flying at an altitude of 60,000 feet will allow 

a wide range of coverage with each airplane providing imagery over a 400-mile path. A 

32-inch diameter ball turret in the nose of each WB-57F houses an optical bench that contains 

HDTV and infrared camera systems. The optics consists of a 4.2-meter fixed focal length lens 

that can be operated in both auto track and manual modes. 

The WAVE aircraft will be used on an experimental basis during the first two return-to-flight 

launches (STS-114 and STS-121). Based on an analysis of the system’s performance and 

quality of the products obtained, NASA will make a decision on whether to continue use of 

this system on future flights. The Critical Design Review for the WAVE was completed on 

July 1, 2004 and the ball turrets were installed in early 2005. The HALO II Gulfstream 

aircraft operated for the Missile Defense Agency is available as a backup airborne tracking 

asset if needed. 

NASA also has assessed using ground based radar for identifying and tracking potential 

debris sources, and new C-band radar on North Merritt Island will be used on STS-114 to 

complement information obtained from the camera systems. 

In addition, NASA is revising the launch requirements and procedures to support an ability to 

capture three useful views of the Shuttle during ascent. Initially, NASA will limit launches to 

daylight hours in order to maximize the ability to capture the most useful ground ascent 

imagery. Camera and tracker operability and readiness to support launch will be supported by 

a new set of pre-launch equipment and data system checks. In addition to certification at the 

Flight Readiness Review, the status of the group imagery assets will be reviewed at the MMT 

Tanking Meeting (approximately L-11 hours) and within one hour of launch. The readiness of 

the camera sites will be reported to the Launch Director at T-20 minutes that will provide 

status to the MMT on the capability to capture three useful views. 

Page 54 of 216 
Final Report of the Return to Flight Task Group 

3.4.4 RTF TG Assessment 

The NASA approach to the CAIB recommendation was to provide an integrated package that 

tied together all three imagery recommendations (R3.4-1, Ground-Based Imagery; R3.4-2, 

High-Resolution Images of External Tank; and R3.4-3, High-Resolution Images of Orbiter), 

and moved the on-orbit inspection capabilities to R6.4-1, Thermal Protection System 

Inspection and Repair. Ultimately, the Task Group decided to consider R3.4-1 and R3.4-2 as 

standalone packages, while R3.4-3 and the inspection portion of R6.4-1 were tightly coupled 

and their final assessments were considered together. 

NASA has made progress toward achieving an integrated suite of ground cameras to capture 

high-resolution images of the Space Shuttle during ascent and has significantly increased the 

number and capability of ground camera sites. Also, the Agency has arranged for airborne 

assets (WAVE) to mitigate the effects of cloud cover and improve higher altitude resolution, 

at least for the first two launches. From a hardware asset perspective, these changes should 

ensure an adequate capability to meet the CAIB intent for three useful views. 

The RTF TG believes that NASA is aware of the limitations inherent in its approach to 

ground imagery. Although the ground cameras provide important engineering data for the 

Space Shuttle during launch and ascent, they do not have the resolution necessary to 

definitively establish that the Orbiter has not suffered ascent debris damage. NASA has stated 

that they will not make any real-time repair decisions directly based on ground imagery data. 

Rather, the comprehensive assessments of Orbiter impacts and damage necessary to ensure 

the safety of the vehicle and crew will be conducted using on-orbit inspection and analysis, 

but focused by ground and ascent imagery. 

Numerous fact-finding activities were conducted by the Task Group beginning in October 

2003 through the closure meeting on November 30, 2004. This final meeting led the Task 

Group to conditionally close their assessment during the December 2004 plenary. The 

conditions included the closure of two requests for information, completing the required 

safety documentation, complete systems testing and verification, training of the operators on 

the new cameras and mounts, incorporating the Ground Imagery Project Summary into the 

overall Program Design Certification Review, completing the Critical Design Review action 

closeout, and completing the standard readiness review process. In addition, prior to return to 

flight, NASA stated that they would add a redundant power source to the system that operates 

the launch pad cameras. 

During a further fact-finding meeting held in January 2005, NASA, together with the 45th 

Space Wing, specified the participants and organizations responsible for certifying mission 

capability during the launch countdown, the reporting mechanisms to launch management for 

imagery asset status, and how the usability of imagery assets will be evaluated when weather 

obstructions exist. The relationship between the Kennedy Space Center and the 45th Space 

Wing on the Eastern Range was clarified, and the Task Group was satisfied that the correct 

agreements were in place between these organizations to ensure status reflecting the 

operability and readiness of assets during the launch countdown. 

Despite the significant progress made in installing and refurbishing the cameras around the 

launch complex, not all of work was able to be completed prior to return-to-flight. NASA 

informed the Task Group that after the launch of STS-114 they will continue to refurbish the 

cameras and mounts per their existing plan, fly the WAVE aircraft in support of STS-121, and 

review the data from WAVE to determine if the concept should continue for future launches. 

Eventually, all borrowed assets will be replaced with planned procurements. 

It should be noted that there is a difference between the NASA implementation and the 

wording of the CAIB recommendation in how the requirements for the camera systems are 

documented. The CAIB wrote that “operational status of these assets should be included in 

Page 55 of 216 
Final Report of the Return to Flight Task Group 

Workers prepare a 

WB-57F aircraft at 

Patrick AFB, Florida. 

The WAVE provides 

both ascent and 

entry imagery and 

enables better 

observation of the 

Space Shuttle on 

days of heavier 

cloud cover and 

areas obscured from 

ground cameras by 

the launch exhaust 

plume. WAVE 

comprises a 32-inchball turret system 

mounted on the nose 

that houses an 

optical bench, 

providing installation 

of both HDTV and 

infrared cameras. 

The system can be 

operated in both 

auto track and 

manual modes. 

the Launch Commit Criteria for future launches.” NASA decided that including these systems 

in the Launch Commit Criteria document was inappropriate, and instead included the 

information in the Program Requirements Document with status reporting in the launch 

countdown procedure. While the Program Requirements Document includes launch support 

requirements, it, alone, does not require the MMT to consider the ground imagery assets as 

part of the launch decision process. A small part of the camera power system was included in 

the Launch Commit Criteria since its status affects multiple camera sites. The Task Group, 

while expressing some concerns, believed this approach was satisfactory. 

The RTF TG assessment of NASA’s actions was completed at the June 8, 2005, meeting. The 

intent of CAIB Recommendation 3.4-1 has been met. 

3.4.5 RTF TG Observations 

While the actions NASA has taken, for the most part, meet the letter of the CAIB 

recommendation, the RTF TG has the following observations: 

1. The approach to documenting the requirements provides launch management 

awareness of the status of these assets. However, it does not require a Launch 

Commit Criteria waiver to proceed with less than three useful views. 

2. The Shuttle should be treated as a developmental vehicle with its performance 

measured for all missions. Imagery has proven to be a useful tool for assessing the 

performance of the Space Shuttle during launch and ascent. Since a substantial 

amount of funds were expended to improve the capability to gather this imagery, 

NASA should retain these assets for the duration of the Space Shuttle Program. 

Page 56 of 216 
Final Report of the Return to Flight Task Group 

3.5 CAIB Recommendation 3.4-2 – 

High-Resolution Images of External Tank 

Provide a capability to obtain and downlink high-resolution images of the External Tank after 

it separates. 

3.5.1 RTF TG Interpretation 

Engineering quality imagery of the External Tank (ET) taken from Columbia after separation 

would have been of great significance in the accident investigation. High-resolution imagery 

of the External Tank should be obtained on each flight and downlinked to the ground as soon 

as practical after achieving orbit. 

3.5.2 Background 

At the time of the Columbia accident, the Orbiters had film cameras installed in each 

umbilical well to provide images of the External Tank following separation. Additionally, 

after ET separation, the Orbiter would be maneuvered into a position that permitted a 

crewmember to take images of the ET using a hand-held digital camera. Following landing, 

the film from the umbilical well cameras was removed and developed for evaluation; the 

hand-held digital camera was downloaded at the same time. These cameras provided images 

of sufficient quality and resolution to permit an engineering evaluation of the ET thermal 

protection system, including foam shedding. Unfortunately, none of these cameras were 

recovered from the Columbia debris. Therefore, no images of the External Tank were 

available to provide engineering insight into foam shedding and debris during the mission. 

3.5.3 NASA Implementation 

To provide the capability to downlink images of the External Tank after separation, NASA 

replaced the 35mm film camera in the Orbiter right umbilical well with a high-resolution 

digital still camera. This 6 megapixel camera uses a 35mm lens and provides a field-of-view 

only slightly smaller than the original film camera. Because of technical complexity and 

limited bandwidth during ascent, the images will not be downlinked in real-time. Rather, once 

the Orbiter is on-orbit and the laptop network is set up in the crew cabin, the images will be 

copied from the camera to a laptop computer then downlinked to the Mission Control Center 

using the existing Orbiter Ku-band link. 

In addition, the flight crew will continue to use a handheld digital still camera with a telephoto 

lens. The Orbiter pitch-over maneuver has been modified to occur sooner after ET separation 

to provide better images from the crew camera. The location where the camera is stowed in 

the crew cabin has also been changed to allow easier access by the crew. The data from the 

digital camera will be transferred to a laptop in the crew cabin and downlinked to Mission 

Control in the same manner as the umbilical well camera images. 

is being carried in 

the right umbilical 

it separates. 

A digital still camera 

well to photograph 

the External Tank as 

Page 57 of 216 
Final Report of the Return to Flight Task Group 

Image of the 

STS-106 External 

Tank taken by the 

umbilical well film 

camera after 

separation. NASA 

has replaced this 

camera with a digital 

camera so that 

images can be 

downlinked to the 

ground during the 

mission. The bipod 

ramps that used to 

be used on the ET 

are clearly visible. 

These images will be used for quick-look analysis by the Mission Management Team to 

determine if any ET anomalies exist that require additional on-orbit inspections (see Section 

3.13, Recommendation 6.4-1). 

A feasibility study for the Orbiter umbilical well camera was initiated in September 2003 and 

the design reviews were completed in April 2004. Modifications to Discovery to support 

STS-114 began in May 2004, and the camera system function testing was completed in March 

2005. The umbilical well camera was installed during Orbiter processing in early April 2005. 

3.5.4 RTF TG Assessment 

The NASA approach to the CAIB recommendation was to provide an integrated package that 

tied together all three imagery recommendations (R3.4-1, Ground-Based Imagery; R3.4-2, 

High-Resolution Images of External Tank; and 3.4-3, High-Resolution Images of Orbiter), 

and moved the on-orbit inspection capabilities to R6.4-1, Thermal Protection System 

Inspection and Repair. Ultimately, the Task Group decided to consider R3.4-1 and R3.4-2 as 

standalone packages, while R3.4-3 and the inspection portion of R6.4-1 were tightly coupled 

and their final assessments were considered together. 

Fact finding was conducted by the Task Group on February 20, 2004, November 15, 2004, 

and during the closure meeting on November 30, 2004. This final meeting led the Task Group 

to close their assessment during the December 2004 plenary. 

Appropriate cameras have been selected to obtain quality views of the External Tank using 

both the handheld camera from the Orbiter and the digital umbilical well camera. The 

STS-114 crew has been trained in use of the hardware, and the digital umbilical well camera 

was installed before OV-103 rolled-out to the launch pad. 

The RTF TG assessment of NASA’s actions was completed at the December 16, 2004, 

meeting. The intent of CAIB Recommendation 3.4-2 has been met. 

3.5.5 RTF TG Observation 

It is our observation that the addition of the digital umbilical well camera to the overall suite 

of imagery planned for STS-114 was vital. This camera requires good lighting in order to 

provide high-quality images during separation. The views obtained from this imagery are, in 

our opinion, critical for evaluating the state of the modified External Tank. 

Page 58 of 216 
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Page 59 of 216 

3.6 CAIB Recommendation 3.4-3 – 

High-Resolution Images of Orbiter 

Provide a capability to obtain and downlink high-resolution images of the underside of the 

Orbiter wing leading edge and forward section of both wings’ Thermal Protection System.

3.6.1 RTF TG Interpretation 

The Columbia Accident Investigation Board (CAIB) investigation was hampered by the lack 

of high-resolution images of the launch ascent trajectory. The only images available were 

from ground cameras that were inadequate in number, placement, and resolution to permit a 

meaningful and timely engineering analysis of the External Tank (ET) thermal protection 

system performance. 

3.6.2 Background 

The damage to the left wing of Columbia occurred shortly after liftoff, but went undetected 

for the entire mission. Although there was photographic evidence from ground cameras of a 

debris impact to the wing, the quality of the imagery hampered a thorough analysis of the 

debris and its potential damage. There was no on-board imagery of the debris strike. 

Many expendable launch vehicles carry cameras pointing toward various parts of the vehicle. 

Usually, these cameras monitor the separation of solid rocket motors, or provide public 

relations value only. Such a camera was mounted on the ET during STS-112 as an experiment 

(the so-called “ET-Cam”). The CAIB believed that this type of camera arrangement could 

provide valuable engineering data if aimed at areas of interest on the Orbiter, such as the main 

landing gear doors and wing leading edges. 

3.6.3 NASA Implementation 

For the first few missions after return to flight, NASA will use primarily on-orbit inspections 

to meet the requirement to assess the health and status of the Orbiter Thermal Protection 

System. This is because the on-vehicle ascent imagery suite does not provide complete 

imagery of the underside of the Orbiter or guarantee detection of all potential impacts to the 

Orbiter. NASA’s detailed implementation of high-resolution images of the Orbiter was 

Two S-band Antennas

• Installed at Sta. 903 in 

Locations 45° off -Z 

Camera Inside Fairing

• Installed in Modified LO2 

Feedline Fairing 

Camera 

Location

Digital Camera 

A digital camera has 

been added to the 

External Tank LO2 

feedline fairing. 
Final Report of the Return to Flight Task Group 

STS-114 and 

STS-121 will carry 

cameras in the 

forward skirt of each 

Solid Rocket 

Booster, in the 

External Tank LO2 

feedline fairing, and 

in the Orbiter 

umbilical well. In 

addition, the crew 

will continue to use 

hand-held cameras 

to photograph the ET 

after separation. 

presented with Recommendation 6.4-1. The two primary methods include Orbiter Boom 

Sensor System (OBSS) and the R-Bar Pitch Maneuver (RPM) imagery; see Section 3.13 

(R6.4-1) for a further discussion. 

In addition, NASA will have cameras on the External Tank liquid oxygen (LO2) feedline 

fairing and the forward skirt of each Solid Rocket Booster. The ET LO2 feedline fairing 

camera will take images of the ET bipod areas and the underside of the Orbiter fuselage and 

the right wing from liftoff through the first 15 minutes of flight. The new location of the ET 

camera will reduce the likelihood that its views will be obscured by the booster separation 

motor plume, a discrepancy observed on STS-112. These images will be transmitted to 

ground stations in real time. 

The SRB forward skirt cameras will take images from 3 seconds to 350 seconds after liftoff. 

These two cameras will look sideways at the ET intertank. The images from this location will 

be stored on the Solid Rocket Boosters and will be available after the SRBs are recovered, 

approximately three days after launch. 

Beginning with STS-115 (the third flight), NASA will introduce an additional complement of 

cameras on the SRBs: aft-looking cameras located on the SRB forward skirt and forwardlooking cameras located on the SRB External Tank Attachment Ring. Together, these 

cameras will provide additional views of the underside of the Orbiter during ascent. 

3.6.4 RTF TG Assessment 

The NASA approach to the CAIB recommendation was to provide an integrated package that 

tied together all three imagery recommendations (R3.4-1, Ground-Based Imagery; R3.4-2, 

High-Resolution Images of External Tank; and 3.4-3, High-Resolution Images of Orbiter), 

and moved the on-orbit inspection capabilities to R6.4-1, Thermal Protection System 

Inspection and Repair. Ultimately, the Task Group decided to consider R3.4-1 and R3.4-2 as 

standalone packages, while R3.4-3 and the inspection portion of R6.4-1 were tightly coupled 

and their final assessments were considered together. 

NASA addressed the Orbiter Boom Sensor System (OBSS) and the R-Bar Pitch Maneuver 

(RPM) as part of CAIB Recommendation 6.4-1. However, these are the capabilities that 

provide evidence that this recommendation has been met and are assessed here. 

Page 60 of 216 
Final Report of the Return to Flight Task Group 

Numerous fact-finding activities were conducted between October 2003 and the closure 

meeting on November 30, 2004. NASA provided a partial closure package for R3.4-3 

concurrently with R3.4-1 and R3.4-2, the other imagery recommendations, and the closure 

presentation covered all three recommendations. However, since NASA moved their 

implementation of the OBSS and the R-Bar Pitch Maneuver into R6.4-1, the Task Group did 

not feel it could close R3.4-3 until the closure package for R6.4-1 was received. 

The closure package for R6.4-1 was received on May 26, 2005. Although the Task Group did 

not feel that the repair portion of the closure package were sufficient to deliberate R6.4-1, the 

portion of the package concerning inspection was complete and R3.4-3 was deliberated at the 

June 8, 2005, plenary meeting in Houston. 

The closure package showed that the primary tool for imaging the wing leading edge on orbit 

will be with the Orbiter Boom Sensor System. There are two sensor packages on the OBSS: 

the laser dynamic range imager (LDRI), which will be used on the lower surface and apex of 

the wing leading edge, and the laser camera system (LCS), which will be used primarily on 

the nosecap. The LDRI has demonstrated, under laboratory conditions, the ability to resolve 

0.25-inch holes and 0.015-inch cracks, while the LCS has shown the ability to resolve 0.125-

inch holes and 0.25-inch coating loss. The Task Group questions whether these resolutions 

can actually be achieved on orbit, and they do not necessarily correspond to the smallest 

critical damage the RCC can withstand; nevertheless they are a significant capability. 

There are some questions remaining regarding the Orbiter Boom Sensor System, which must 

be resolved operationally. These include the clearance between the OBSS and the Ku-band 

antenna in the retracted position, and analysis of LDRI cable clearance with the Orbiter 

radiator and CMG payload. NASA assures the Task Group that these items will not affect the 

operation of the OBSS during STS-114. 

The primary method for imaging the acreage tiles on the bottom of the Orbiter and the surface 

insulation on top of the Orbiter will be via photography from the ISS during the R-Bar Pitch 

Maneuver while the Orbiter is approaching the station to dock. These images provide 

adequate resolution to initiate a more-focused inspection using the OBSS, if required. 

The RTF TG assessment of NASA’s actions was completed at the June 8, 2005, meeting. 

Inside the Orbiter 

Processing Facility 

bay 3 at the 

Kennedy Space 

Center, Discovery’s 

payload bay doors 

are ready to be 

closed. Seen in the 

center (starboard 

side) and at right are 

the new Orbiter 

Boom Sensor 

System (OBSS) and 

the Shuttle Remote 

Manipulator System 

(SRMS). The black 

object in the 

foreground is the 

Ku-band antenna. 

Page 61 of 216 
Final Report of the Return to Flight Task Group 

The 50-foot long 

OBSS attaches to 

the end of the SRMS 

and provides the 

capability to inspect 

all of the RCC on the 

Orbiter as well as 

most of the 

underside tiles. 

The OBSS boom is 

very similar to the 

standard Remote 

Manipulator System 

boom the Orbiter has 

carried on most of its 

missions. The RMS 

attaches to the 

OBSS and provides 

power and control to 

the new boom. Two 

new imaging 

systems are located 

at the end of the 

OBSS. 

With the provision that the forward work, described previously, is completed, the Task Group 

feels that the intent of CAIB Recommendation 3.4-3 has been met. 

3.6.5 RTF TG Observation 

The Task Group believes that on-vehicle ascent imagery will be a valuable source of 

engineering, performance, and environment data and will be useful for understanding in-flight 

anomalies. The new location of the ET camera should reduce the likelihood that the camera 

will be obscured by the booster separation motor plume. The RTF TG cautions, however, that 

this on-vehicle ascent imagery suite does not provide complete imagery of the underside of 

the Orbiter or guarantee detection of all potential impacts to the Orbiter. 

The certified resolution of the OBSS sensor suite does not meet critical damage size criteria. 

NASA has committed to retain an on-orbit inspection capability after the OBSS can no longer 

be flown. The RTF TG strongly endorses that commitment. 

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Final Report of the Return to Flight Task Group 

3.7 CAIB Recommendation 4.2-1 – 

Solid Rocket Booster Bolt Catcher 

Test and qualify the flight hardware bolt catchers. 

3.7.1 RTF TG Interpretation 

The meaning of the CAIB recommendation is clear. 

3.7.2 Background 

A fault tree review conducted for the Columbia Accident Investigation Board (CAIB) 

uncovered a significant problem with the Solid Rocket Booster (SRB) bolt catchers. Each 

SRB is connected to the External Tank (ET) by four separation bolts: three at the bottom plus 

a larger one at the top that weighs approximately 65 pounds. These larger upper (or 

“forward”) separation bolts (one on each SRB) and their associated bolt catchers on the 

External Tank were the subject of a great deal of scrutiny by the CAIB. 

About two minutes after launch, pyrotechnic charges break each forward separation bolt into 

two pieces, allowing the spent SRBs to separate from the External Tank. Two “bolt catchers” 

on the ET each trap the upper half of a fired separation bolt, while the lower half stays 

attached to the Solid Rocket Booster. As a result, both halves are kept from flying free of the 

assembly and potentially hitting the Orbiter. Bolt catchers have a domed aluminum cover 

containing an aluminum honeycomb matrix that absorbs the energy of the fired bolt. The two 

upper bolt halves and their respective catchers subsequently remain connected to the External 

Tank, which burns up during reentry, while the lower halves stay with the Solid Rocket 

Boosters that are recovered from the ocean. 

If one of the bolt catchers had failed during STS-107, the resulting debris could have damaged 

the wing leading edge of Columbia. Concerns that the bolt catchers may have failed, causing 

metal debris to ricochet toward the Orbiter, arose because the configuration of the bolt 

catchers used on Space Shuttle missions differed in important ways from the design used for 

the initial qualification tests. Despite the extensive CAIB analyses, the accident board also 

was not able to determine that the SRB bolt catchers, while an unlikely cause, could be 

definitively excluded as a potential cause the damage that doomed Columbia. 

Static and dynamic testing, conducted as a result of the CAIB inquiries, demonstrated that the 

bolt catchers flown on STS-107 had a factor of safety of 0.956, rather than 1.4 as required by 

specification. The CAIB and NASA also identified additional reasons to be concerned about 

the bolt catchers. The bolt catchers did not meet their established requirements; specifically, 

the thermal protection system for the assembly was not qualified for the separation shock 

environment; failures of the bolt catcher attach fasteners or inserts could lead to debris; and 

the ejection effects of the NASA standard initiator (NSI) from its pressure cartridge during 

bolt firing were not included in the original bolt catcher qualification. 

3.7.3 NASA Implementation 

The bolt catcher assembly and related hardware has been redesigned. The bolt catcher 

housing is now fabricated from a single-piece aluminum forging that removes the weak point 

at the weld from the original design. The strength of the housing has been increased by 

doubling the thickness and using a stronger aluminum. Further, NASA has redesigned and 

resized the bolts and inserts that attach the bolt catcher to the ET, using larger and stronger 

fasteners. The housing design was enhanced with an integral O-ring carrier design that 

eliminated a separate carrier and one O-ring. The assembly’s thermal protection system is 

replaced by machined cork with enhanced adhesion properties to reduce the potential for 

Page 63 of 216 
Final Report of the Return to Flight Task Group 

debris, and a new honeycomb energy absorber was introduced to reduce the loads. Mandatory 

government inspection points have been added for the thermal protection system, structure, 

and energy absorber with 100-percent surveillance of all manufacturing processes during final 

assembly. This new assembly was qualified by testing as a complete system to demonstrate 

compliance with NASA factor-of-safety and debris requirements. 

The bolt catchers 

were extensively 

redesigned after 

STS-107, and 

subjected to a fullrange of qualification 

testing. 

The forward ET-SRB 

separation bolt is 

broken in half when 

the SRBs are 

jettisoned. It is the 

ET half of this bolt 

that the bolt catchers 

are intended to 

capture. 

STS-107 Bolt Catcher Design STS-114 Bolt Catcher Redesign 

Bolt Catcher Design 

TPS material 

SLA-561 

Machined Cork 

Housing 

2 pc. welded; 2219 Al; 1/8 in. thick 

1 pc.; 7050 Al; 1/4 in. thick 

Energy Absorber 

Spiral Wound 5052 Al; 

1400 psi crush; 

10 holes drilled 

5052 Al Honeycomb; 

828 psi crush 

Fasteners 

A286; 3/8 in.; 180 ksi 

MP35N; 9/16 in.; 260 ksi 

O-ring Carrier 

Separate 

Integrated 

NSI 

Forward Separation Bolt Housing 

SRB Half ET Half 

Primary Piston Secondary Piston 

Insert

Pressure Cartridge Lead Coupler

NASA has completed the redesign of the bolt catcher assembly and its associated hardware. 

Critical Design Reviews were completed for both the bolt catcher and the NSI pressure 

cartridge in May 2004. Development testing completed to date includes: energy absorber 

characterization; bolt catcher system drop and firing test; bolt catcher structural tests; bolt 

catcher attachment fastener prying and bending test; separation bolt velocity determination; 

NSI pressure cartridge and retention device quick look margin tests; NSI pressure cartridge 

burst tests; and NSI pin ejection simulations. Thermal protection system qualification testing 

was completed in August 2004. 

Qualification testing of the bolt catcher assembly, to the original specifications, was begun in 

July 2004. During the final qualification test simulating NSI pin ejection firing, results 

showed that the actual crush depth was less than the predicted crush depth. (Crush depth is the 

measurement of the distance the bolt travels into the energy absorber inside the bolt catcher.) 

The difference between actual and predicted crush depth was determined to be caused by 

Page 64 of 216 
Final Report of the Return to Flight Task Group 

Polymer Development Laboratories (PDL) foam and the energy absorber counterbore. In 

order to improve crush depth prediction accuracy, the PDL foam and energy absorber 

counterbore were eliminated by reducing the length of the energy absorber. Testing shows 

this reduction in length is acceptable because the longer energy absorber was added before the 

maximum bolt velocity was established. Subsequent testing proved that the bolts have a lower 

maximum velocity than the design allows; therefore shortening the energy absorber does not 

alter the effectiveness of the bolt catcher. However, it does allow for greater predictability of 

crush depth. Qualification testing was completed in October 2004. 

3.7.4 RTF TG Assessment 

The RTF TG conducted multiple fact-finding trips 

in support of the bolt catcher recommendation. The 

Task Group also supported several design reviews, 

including the Delta Critical Design Review (CDR) 

on April 28-30, 2004, and the Design Certification 

Review on November 22, 2004. 

The bolt catcher for the SRB to ET separation bolt has been modified to provide an adequate 

safety factor, per the original specification. The STS-107 design was a two-piece welded 

assembly and the new design is based on a one-piece forging. The energy absorber used to 

attenuate the bolt impact load has been redesigned as well. Additionally, the thermal 

protection system has been changed from a sprayed-on material to bonded cork. The NASA 

standard initiator in the pressure cartridge had exhibited an ejection failure mode during 

several tests which could damage the energy absorber prior to bolt impact. This issue has been 

addressed by the incorporation of a locking ring assembly to aid in retention of the NSI. 

The SRB bolt catcher has successfully completed qualification testing and has demonstrated a 

minimum structural factor of safety of 1.86. The new assembly was qualified by testing as a 

complete system to demonstrate compliance with NASA factor-of-safety and debris 

requirements. Additionally, the NSI retention device has been determined to exhibit a 

minimum factor of safety of 2.3. The redesigned bolt catcher has successfully completed 

Level IV DCR. 

The RTF TG assessment of NASA’s actions was completed at the December 16, 2004 

meeting. The intent of CAIB Recommendation 4.2-1 has been met. 

The bolt catchers for 

ET-120, originally 

intended for use on 

STS-114, during their 

installation at the 

Kennedy Space 

Center. The bolt 

catchers used on 

ET-121, the tank 

actually used for 

STS-114, were 

identical. 

Page 65 of 216 
Final Report of the Return to Flight Task Group 

being 

lifted onto the stack 

for use during 

wi

Tank forced the 

the stack planned for 

Discovery

originally intended 

STS-114. Anomalies 

th this External 

eventually switch to 

use on STS-121. 

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Final Report of the Return to Flight Task Group 

3.8 CAIB Recommendation 4.2-3 – 

Two-Person Closeout Inspections 

Require that at least two employees attend all final closeouts and intertank area handspraying procedures. 

3.8.1 RTF TG Interpretation 

The Columbia Accident Investigation Board (CAIB) subsequently clarified that this 

recommendation was intended to apply across the entire Space Shuttle Program for all types 

of closeouts; although the External Tank (ET) intertank was specifically called out, the 

recommendation was not intended to be limited to this area. The RTF TG therefore 

interpreted this recommendation to mean that NASA should review and update all of their 

process controls to ensure that at least two people observe all final closeout activities in 

critical areas. 

3.8.2 Background 

In its report, the CAIB remarked on the Agency’s overall success in improving security 

following September 11, 2001. At that time, NASA embarked upon a comprehensive review 

of all security procedures in place and all Space Shuttle Program projects and elements 

cooperated with their host Centers and NASA Headquarters, Office of Security Management 

and Safeguards, to review NASA and contractor security procedures and implementing a wide 

array of improvements. This review encompassed the entire scope of security-oriented 

activities, including hiring procedures, personnel reliability assurance programs, physical site 

security, specific anti-terrorism measures, and manufacturing and processing procedures. 

The CAIB report (pp. 93-94) provides additional detail into the possibility that willful damage 

contributed to the STS-107 accident. The accident board’s investigation determined that this 

was not a credible potential cause of intertank foam debris. 

During this security review, however, the CAIB identified several processes that did not 

require two people to be present when an area on the flight vehicle was closed-out. Although 

unlikely, this could allow an individual to sabotage the vehicle without being observed. 

Equally as important, this was counter to the general policy of “two sets of eyes are better 

than one” that provides additional technical and safety checks during closeouts. 

3.8.3 NASA Implementation 

The External Tank Project amended all manufacturing processes and procedures to ensure 

that at least two employees, and in most cases several more, are present at all manufacturing 

steps. This includes manual foam applications and all other closeouts, both at Michoud 

Assembly Facility and the Kennedy Space Center. Furthermore, NASA implemented morestringent quality assurance requirements and provided additional employee training, 

certification, and work documentation of inspections and imagery. 

In response to additional guidance provided by the RTF TG in April 2004, NASA widened 

the scope of its corrective measures by issuing additional direction for all major flight 

hardware and ground processing elements to conduct an audit of their final closeout 

procedures and protocols. The audit included a review of quality assurance closeout protocols 

and the protection they offer against willful damage. This audit was completed on April 30, 

2004 and the results forwarded to the Task Group shortly afterward. 

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Final Report of the Return to Flight Task Group 

In the back of the 

Orbiter Processing 

Facility bay 3, 

workers check one of 

the thermal 

protection system 

blanket ground wires 

to ensure a proper 

ground between the 

blanket and the 

Orbiter Boom Sensor 

System (OBSS). The 

installation will 

conclude TPS 

closeout prior to 

installation of the 

boom in Discovery. 

At least two workers 

are present for all 

closeout activities. 

3.8.4 RTF TG Assessment 

The Task Group conducted several fact-finding activities during early 2004. A closure 

package was received by the RTF TG in time for this recommendation to be considered at the 

April 2004 plenary meeting. The Task Group assessed the Agency’s implementation of this 

recommendation and determined that NASA was defining the accident board’s intent too 

narrowly. The Task Group’s fact-finding site visits, review of the CAIB report, and 

correspondence with members of the CAIB, led them to suggest that NASA should widen its 

perspective to include all flight hardware elements, rather than just the External Tank. 

Nevertheless, sufficient progress had been made for the Task Group to conditionally close 

their assessment at the April 16, 2004, public meeting. 

Accordingly, NASA widened the scope of its corrective effort to conduct a program-wide 

audit of all final closeouts for major flight hardware elements, both at the manufacturing sites 

and at the Kennedy Space Center. This audit was completed on April 30, 2004, and all revised 

requirements were incorporated into the appropriate documentation by January 2005. 

The results from this audit were received by the RTF TG on December 8, 2004, and the 

results presented in the closure package were considered satisfactory. NASA provided data on 

the documentation that had been updated, also to the Task Group’s satisfaction. 

The RTF TG assessment of NASA’s actions was completed at the December 16, 2004 

meeting. The intent of CAIB Recommendation 4.2-3 has been met. 

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Final Report of the Return to Flight Task Group 

3.9 CAIB Recommendation 4.2-5 – 

KSC Foreign Object Debris Definition 

Kennedy Space Center Quality Assurance and United Space Alliance must return to 

straightforward, industry-standard definition of “Foreign Object Debris” and eliminate any 

alternate or statistically deceptive definitions like “processing debris.” 

3.9.1 RTF TG Interpretation 

During their investigation and interviews with personnel involved with processing the Space 

Shuttle for flight, the Columbia Accident Investigation Board (CAIB) determined that during 

January 2001 the Kennedy Space Center (KSC) generated new and non-standard definitions 

for Foreign Object Debris (FOD) which were fully implemented at KSC in June 2002. The 

term “processing debris” was applied to debris found during the routine processing of the 

flight hardware. The term FOD applied only to debris found in flight hardware after final 

closeout inspections. These definitions were unique to the Space Shuttle Program at the KSC. 

Because debris of any kind has critical safety implications, these definitions are important. 

Accordingly, the CAIB wanted the standard, industry-wide definitions reestablished for FOD. 

3.9.2 Background 

Problems with the Kennedy Space Center and United Space Alliance (USA) Foreign Object 

Damage Prevention Program, which in the Department of Defense and aviation industry 

typically falls under the auspices of Quality Assurance, were related to changes made during 

2001. In that year, Kennedy Space Center and United Space Alliance redefined the single 

term “Foreign Object Damage” – an industry-standard term – into two categories: “Processing 

Debris” and “Foreign Object Debris.” 

Processing Debris: 

Any material, product, substance, tool or aid generally used during the processing of 

flight hardware that remains in the work area when not directly in use, or that is left 

unattended in the work area for any length of time during the processing of tasks, or 

that is left remaining or forgotten in the work area after the completion of a task or 

at the end of a work shift. Also any item, material or substance in the work area that 

should be found and removed as part of standard housekeeping, Hazard Recognition 

and Inspection Program (HRIP) “walk-downs”, or as part of “Clean As You Go” 

practices. 

Foreign Object Debris: 

Processing debris becomes FOD when it poses a potential risk to the Shuttle or any 

of its components, and only occurs when the debris is found during or subsequent to 

a final/flight Closeout Inspection, or subsequent to OMI S0007 ET Load SAF/FAC 

“walk-down.” 

These definitions were inconsistent with those of other NASA Centers, the Department of Defense, commercial aviation, and National Aerospace FOD Prevention, Inc., guidelines. 

Because debris of any kind has critical safety implications, the CAIB believed these 

definitions were important. 

3.9.3 NASA Implementation 

The Kennedy Space Center and United Space Alliance have changed work procedures to 

consider all debris equally important and preventable. Rigorous definitions of FOD that are 

Page 69 of 216 
Final Report of the Return to Flight Task Group 

the industry standard have been adopted. These new definitions adopted from National 

Aerospace FOD Prevention, Inc. guidelines and industry standards include Foreign Object 

Debris, Foreign Object Damage, and Clean-As-You-Go. FOD is redefined as “a substance, 

debris or article alien to a vehicle or system which would potentially cause damage.” 

The new FOD program is anchored in three fundamental areas of emphasis. First, it 

eliminates various categories of FOD, including “processing debris,” and treats all FOD as 

preventable and with equal importance. Second, it reemphasizes the responsibility and 

authority for FOD prevention at the operations level. FOD prevention and elimination are 

stressed and the work force is encouraged to report any and all FOD found by entering the 

data in the FOD database. This activity is performed with the knowledge that finding and 

reporting FOD is the goal of the Program and employees will not be penalized for their 

findings. Third, it elevates the importance of comprehensive independent monitoring by both 

contractors and the Government. 

United Space Alliance has also developed and implemented new work practices and 

strengthened existing practices. This new rigor will reduce the possibility for temporary 

worksite items or debris to migrate to an out-of-sight or inaccessible area, and it serves 

an important psychological purpose in 

eliminating visible breaches in FOD 

prevention discipline. 

The new FOD program has a meaningful set 

of metrics to measure effectiveness and to 

guide improvements. FOD walkdown 

findings will be tracked in the Integrated 

Quality Support Database. This database 

will also track FOD found during closeouts, 

launch countdowns, post-launch pad 

turnarounds, landing operations, and NASA 

quality assurance audits. “Stumble-on” 

FOD findings will also be tracked, as they 

offer an important metric of program 

effectiveness independent of planned FOD 

program activities. For all metrics, the types of FOD and their locations will be recorded and 

analyzed for trends to identify particular areas for improvement. Monthly metrics reporting to 

management will highlight the top five FOD types, locations, and observed workforce 

behaviors, along with the prior months’ trends. Continual improvement will be a hallmark of 

the revitalized FOD program. 

The implementation of the new program began on July 1, 2004, although many aspects of the 

plan existed in the previous FOD prevention program in place at KSC. Assessment audits by 

NASA and United Space Alliance were conducted beginning in October 2004. Corrective 

Action Plans have been established to address the findings and observations identified during 

the two audits. Schedules for the verification of the actions taken and for verifying the 

effectiveness of the corrective actions have been established to ensure the ongoing 

effectiveness of the FOD prevention program. Continual improvement will be vigorously 

pursued for the remainder of the life of the Space Shuttle. 

3.9.4 RTF TG Assessment 

The FOD Program at the Kennedy Space Center was very effective in the past. When the 

definitions were modified during 2001 to create multiple categories of debris, the workforce 

was not sufficiently trained to understand the implications. This confusion was expressed to 

the CAIB members during their interviews with KSC personnel; in response to the CAIB 

recommendation, KSC reevaluated the entire program. The Task Group concluded factPage 70 of 216 
Final Report of the Return to Flight Task Group 

finding during a technical interchange meeting at KSC in May 2004. This complemented 

previous meetings with KSC quality assurance and United Space Alliance personnel in late 

2003 and early 2004. 

The Kennedy Space Center and United Space Alliance have changed the definition of 

“Foreign Object Debris” to be consistent with the recognized and accepted industry standard. 

Further, they have removed the misleading category of processing debris that caused concern. 

They have improved the training of the workforce, and obtained buy-in at all levels for both 

NASA and all contractors. The revised program has implemented several improvements 

above and beyond the expectations defined in the CAIB recommendation. The FOD database 

has been made significantly more robust and captures a higher level of reporting detail than 

existed previously. NASA management has demonstrated their buy-in with participation in 

“walk-downs” to inspect for FOD. 

The RTF TG initial assessment of NASA’s actions was completed at the July 22, 2004, 

teleconference plenary where the assessment was conditionally closed. After receiving audit 

results and specified corrective actions from NASA, the assessment was closed at the 

December 16, 2004, meeting. The intent of CAIB Recommendation 4.2-5 has been met. 

3.9.5 RTF TG Observation 

It is very important for NASA management to provide positive incentives for the reporting of 

FOD and to avoid negative sanctions for those who self-report. The Task Group believes 

management is sufficiently sensitive to this need and will provide the proper positive and 

negative feedback to the workforce. Metrics defined and tracked by NASA will assure 

continued compliance with the new improved FOD program. 

Discovery during 

early processing for 

STS-114. The 

reinforced carboncarbon nosecap had 

been removed and 

returned to the 

vendor for testing. 

Note the open nose 

landing gear door at 

the bottom left. 

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on her 

Mobile Launch 

Complex 39B. 

The CrawlerTransporter drives 

away after delivering 

Discovery

Platform to Launch 

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Final Report of the Return to Flight Task Group 

3.10 CAIB Recommendation 6.2-1 – 

Consistency with Resources 

Adopt and maintain a Shuttle flight schedule that is consistent with available resources. 

Although schedule deadlines are an important management tool, those deadlines must be 

regularly evaluated to ensure that any additional risk incurred to meet the schedule is 

recognized, understood, and acceptable. 

3.10.1 RTF TG Interpretation 

The Columbia Accident Investigation Board (CAIB) explicitly recognized the legitimate use 

of schedules to drive a process. They were concerned, however, that the line between 

“beneficial” schedule pressures and those that become detrimental, cannot be easily defined or 

measured. In the case of Columbia, the CAIB discovered that pressure on the Space Shuttle 

Program was created by the schedule for construction of the International Space Station. 

Indeed, the planned February 2004 completion of Node 2 of the International Space Station 

was being touted as a measure of NASA’s ability to maintain a schedule. 

The CAIB further observed that budget constraints inherently intensify the conflicts between 

schedule and safety. The meaning of the first sentence of the CAIB recommendation is clear: 

adjust the schedule to fit the available resources. 

3.10.2 Background 

During the course of the Columbia investigation, the CAIB received several unsolicited 

comments from NASA personnel regarding pressure. Oddly, the pressure was to meet a date 

more than a year after the launch of STS-107 that seemed etched in stone: February 19, 2004, 

the scheduled launch of STS-120. This flight was a milestone in the minds of NASA 

management since it would carry a section of the International Space Station called “Node 2” 

that would signal “U.S. Core Complete.” 

At first glance, the U.S. Core Complete date seemed noteworthy but unrelated to the 

Columbia accident. However, as the investigation continued, it became apparent to the 

accident board that the political mandates surrounding the International Space Station 

Program, as well as the Space Shuttle Program management’s responses to them, resulted in 

pressure to meet an increasingly ambitious launch schedule. 

Meeting U.S. Core Complete by February 19, 2004 – a date the CAIB found was promised by 

NASA management to the White House and Congress – would require launching 10 Space 

Shuttle missions in less than 16 months. With the focus on retaining political support for the 

International Space Station Program, little attention was paid to the effects the aggressive 

Node 2 launch date would have on the Space Shuttle Program. After years of downsizing and 

budget cuts, this mandate introduced elements of risk, and the high-pressure environments 

created by NASA Headquarters unquestionably affected Columbia, even though it was not 

flying to the International Space Station. 

After considering what they had uncovered during their investigation, the CAIB concluded: 

“The agency’s commitment to hold firm to a February 19, 2004, launch date for 

Node 2 influenced many of decisions in the months leading up to the launch of 

STS-107, and may well have subtly influenced the way managers handled the 

STS-112 foam strike and Columbia’s as well. 

“When a program agrees to spend less money or accelerate a schedule beyond what 

the engineers and program managers think is reasonable, a small amount of overall 

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risk is added. These little pieces of risk add up until managers are no longer aware of 

the total program risk, and are, in fact, gambling. Little by little, NASA was 

accepting more and more risk in order to stay on schedule.” 

3.10.3 NASA Implementation 

NASA has strengthened a risk management system that it believes balances technical, 

schedule, and resource risks to achieve safe and reliable operations. Under this system, safety 

is ensured by first focusing on the technical risks and taking the time and financial resources 

necessary to properly resolve them. Once technical risks are reduced to an acceptable level, 

program managers turn to the management of schedule and resource risks to preserve safety. 

Among the activities NASA plans to undertake are more routinely assessing schedule risk, 

incorporating additional margin into the schedule and manifest to accommodate changes, and 

revising databases so schedule and risk indicators can be assessed by managers in real-time. 

KSC and United Space Alliance management use the Equivalent Flow Model (EFM) to plan 

resources that are consistent with the Space Shuttle flight schedule and available workforce 

needed to meet the technical requirements. The EFM is a computerized tool that uses a 

planned manifest and past performance to calculate processing resource requirements. The 

workforce, a primary input to the EFM tool, comprises fixed resources, supporting core daily 

operations, and variable resources that fluctuate depending on the manifest. Using past 

mission timelines and actual hours worked, an “equivalent flow” is developed to establish the 

required processing hours for a processing flow. 

To assess and manage the manifest, NASA has developed a process called the Manifest 

Assessment System that incorporates all manifest constraints and influences, and allows 

adequate margin to accommodate a normalized amount of changes. This process entails 

building in launch margin, cargo and logistics margin, and crew timeline margin while 

preserving the technical element needed for safe and reliable operations. United Space 

Alliance is using the Manifest Assessment System to assess the feasibility of proposed 

technical and manifest changes to determine how changes to facility availability, schedule, or 

duration of flight production activities affect the overall manifest schedule. This capability 

enables a more useful way to implement realistic, achievable schedules while successfully 

balancing technical, schedule, and resource risks to maintain safe and reliable operations. 

Policies are also in place to ensure the workforce health at KSC in the face of schedule 

deadlines. The Maximum Work Time Policy, found in KSC Handbook (KHB) 1710.2, section 

3.4 includes daily, weekly, monthly, yearly, and consecutive hours worked limitations. 

Deviations require senior management approval up to the KSC Center Director and 

independent of the Space Shuttle Program. KSC work time safeguards ensure that when 

available resource capacity is approached, the schedule is adjusted to safely accommodate the 

added work. When possible, launches are planned on Wednesdays or Thursdays to minimize 

weekend hours and associated costs; repeated launch attempts are scheduled to reduce crew 

and test team fatigue. Overtime hours and safety hazard data are continually monitored by 

KSC and Space Shuttle Program management for indications of workforce stress. 

3.10.4 RTF TG Assessment 

The CAIB explored a number of root causes for the Columbia accident; one of these was the 

desire to maintain a schedule for achieving U.S. Core Complete during construction of the 

International Space Station. The ISS Program had a long history of cost and schedule 

overruns and had been the subject of numerous Congressional hearings and independent 

commissions. NASA was determined to complete construction with as few additional 

budgetary resources as possible. In this environment, there was a reluctance to expend the 

resources to investigate obvious problems with the Space Shuttle, among them the shedding 

of foam from the External Tank (ET). Damage to a Solid Rocket Booster – caused by foam 

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Final Report of the Return to Flight Task Group 

from the ET – two flights before Columbia, prompted a study into the anomaly, but even this 

was not enough to cause anyone to waiver from the schedule. 

Thus CAIB recommended that NASA “Adopt and maintain a Space Shuttle flight schedule 

that is consistent with available resources...” Recognizing the ongoing nature of this 

recommendation, the Task Group believes it will take vigilance in the future to maintain the 

“appropriate” pressure necessary to maintain a schedule for such a complex system without 

the pressure becoming, for any reason, “undue.” 

Recognizing the difficulty in assessing this recommendation, the Task Group undertook 

several activities in an attempt to evaluate the presence of “undue” schedule pressure and the 

general availability of resources. The Task Group consistently explored the question of 

adequacy of resources in virtually every meeting with NASA personnel – from Headquarters 

staff to the workforce on the floor of the Kennedy Space Center. The answer has always been 

the same: “...there are sufficient budgetary resources for return to flight.” 

Recognizing that any assessment is a snapshot, the Task Group also requested data on 

overtime and other work rule exceptions. The RTF TG looked at reports on sick leave, 

employee assistance visits, accidents, and near-accidents (close-calls or “diving catches”), as 

well as reports of problems with the quality of workmanship being performed. Altogether, 

these data, compared with previous intervals prior to launch, showed no unusual patterns 

suggestive of substantial adverse pressure. 

During the middle of 2004, press reports claimed NASA personnel were concerned about 

resources and the possibility of workforce reductions. The RTF TG was not able to confirm 

these reports and notes most were made prior to the finalization of the Fiscal Year 2005 

NASA budget, during a time when exercises were being conducted to assess the impacts of 

various alternative levels of spending. NASA was one of the few federal agencies to receive 

full funding, although funding for aeronautics programs was severely cut to fund space 

initiatives, particularly the Vision for Space Exploration. 

The Task Group also had the opportunity to assess the outcome of NASA’s budget requests 

over the last two years. Last year (FY05), Congress actually added funds to the request to 

augment return-to-flight activities, and this year has taken actions to help protect resources for 

NASA in the future. And while NASA has somewhat reduced funding for the Headquarters 

Office of Safety and Mission Assurance, the Task Group has been assured these reductions 

will have no effect on return-to-flight activities. 

The RTF TG assessment of NASA’s actions was completed at the June 8, 2005, meeting. The 

intent of CAIB Recommendation 6.2-1 has been met. 

3.10.5 RTF TG Observations 

Resource sufficiency is also tied to the scheduled retirement date for the Space Shuttle, and 

any evaluation of whether to keep Space Shuttle in service past 2010 should include a 

reassessment of actions and upgrades not undertaken, and any long term items already deleted 

from work and acquisition cycles, including the Service Life Extension Program. 

The Task Group also observes that resource constraints will likely pressure future programs, 

such as the Vision for Space Exploration. There will always be pressure for under-funding 

and overly-aggressive scheduling that must be recognized and mitigated by senior leadership. 

Along these lines, NASA must address the size and mixture of its future workforce to 

accomplish its new missions. 

As new NASA space flight programs evolve, the Space Shuttle could well be caught between 

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Final Report of the Return to Flight Task Group 

competing goals (e.g., the 2010 retirement date, Hubble SM4, and the delays in fielding a new 

vehicle). NASA will need to exercise great rigor to ensure that competing budgetary 

requirements do not affect the safety and reliability of Space Shuttle. 

at the 

beginning of her 

seen from inside the 

Vehicle Assembly 

Building. 

Discovery

slow trip to Launch 

Complex 39B, as 

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Final Report of the Return to Flight Task Group 

3.11 CAIB Recommendation 6.3-1 – 

Mission Management Team Improvements 

Implement an expanded training program in which the Mission Management Team faces 

potential crew and vehicle safety contingencies beyond launch and ascent. These 

contingencies should involve potential loss of Shuttle or crew, contain numerous uncertainties 

and unknowns, and require the Mission Management Team to assemble and interact with 

support organizations across NASA/Contractor lines and in various locations. 

3.11.1 RTF TG Interpretation 

Mission Management Team (MMT) activities during the flight of Columbia have been widely 

criticized. Many of the additional capabilities embedded in other recommendations from the 

Columbia Accident Investigation Board (CAIB), such as imagery from various sources, are 

intended to support MMT activities for the next and subsequent flights. In addition to 

enhanced training for participants in the MMT, the Agency will need to exercise these many 

new sources of data and information. 

3.11.2 Background 

The CAIB report was very clear on the importance the accident investigation board placed on 

correcting the organizational behaviors which led to the multiple STS-107 MMT decision 

making failures they identified. Indeed, the CAIB issued 29 findings related to these failures, 

ranging from lapses in MMT leadership and communication, to the passivity of MMT safety 

representatives, to the lack of reliance on solid analysis and engineering data, to the absence 

of effective mechanisms for expressions of concern or dissent. 

According to NSTS 07700, Volume VIII, Appendix D, the MMT is “the program decisionmaking body responsible for making programmatic trades and decisions associated with 

launch countdown and in-flight activities ... outside the responsibility or authority of the 

Launch Director or Flight Director.” Throughout STS-107, the CAIB found that the MMT 

(and its processes and procedures) failed to support or result in timely, informed, or effective 

critical decisions. In short, the MMT failed in the performance of its mission. 

During Space Shuttle missions, the Mission Management Team is responsible for oversight of 

the launch and flight operations teams. The countdown and flight operations are conducted to 

rules and procedures approved by program management and are documented in NSTS 07700, 

Volume VIII. The MMT provides guidance to the operations teams during situations that fall 

outside normal operations; the MMT also redefines programmatic priorities when in-flight 

anomalies or off-nominal conditions result in conflicting priorities. 

The MMT responsibilities for a specific Space Shuttle mission begin with a scheduled 

meeting two days prior to a scheduled launch (L-2). The MMT Chair, supported by the entire 

MMT, is responsible for the final GO/NO-GO decision for launch. MMT activities at the 

Kennedy Space Center continue through launch and terminate upon the declaration by the 

Flight Director of “Go for On-Orbit Operations,” approximately 2 hours after launch. At that 

time, MMT activities transfer to the Johnson Space Center. The flight MMT meets daily 

during the subsequent on-orbit, entry, and landing phases, and terminates with crew egress 

from the Orbiter. When the MMT is not in session, all members are on-call and required to 

support emergency meetings convened because of anomalies or changing flight conditions. 

As exhibited during STS-107, the MMT had become somewhat ad hoc and informal in 

nature; there was no clear method to formally present issues in an official forum. Therefore, 

the concerns of individual engineers, the quality of risk assessments, and the pedigree of 

engineering assessments were sometimes poorly understood by senior management. In 

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Final Report of the Return to Flight Task Group 

retrospect, this approach did not adequately sensitize NASA management in general – and the 

MMT, in particular – to actively seek out potential concerns and issues raised by individuals, 

support teams, and working groups. 

3.11.3 NASA Implementation 

As a result of the CAIB findings and recommendations, the Space Shuttle Program began to 

identify necessary changes to the MMT in May 2003. A Space Shuttle Program Requirements 

Change Board on September 11, 2003, reviewed the proposed changes and presented a 

slightly modified set to the Space Flight Leadership Council on November 21, 2003. The 

changes included expanding the MMT membership, better defining member responsibilities, 

making the flight MMT meetings more formal, establishing a time reporting process, and 

establishing a rigorous process for the review and disposition of mission anomalies and 

issues. In addition, NASA contracted with several external evaluators (experts in training and 

critical decision making) and several past flight directors, including Gene Kranz and Glynn 

Lunney, to study the MMT processes and make recommendations to improve 

communications, decision-making, and operational processes. 

NASA established a process for the review and resolution of off-nominal mission events to 

ensure that all such issues are identified to and resolved by the flight MMT. The Space Shuttle 

Systems Engineering and Integration Office will maintain and provide an integrated anomaly 

list at each MMT meeting. All anomalies will be assigned a formal office of primary 

responsibility (OPR) for technical evaluation and will be subject to an independent risk 

assessment by Safety and Mission Assurance (SMA). The MMT has one Space Shuttle 

Program SMA core member and three institutional SMA advisory members from JSC, KSC, 

and MSFC. In addition, the MMT has added the Space Shuttle System Technical Warrant 

Holder as a core member; this person represents the NASA Independent Technical Authority 

as a voting member. The NASA Engineering and Safety Center (NESC) also serves as a 

formal advisor to the MMT. 

The MMT secretary will maintain an action tracking log to ensure all members are adequately 

informed of the status of all anomalies. Closure of actions associated with each anomaly will 

require a formal written request that includes a description of the issue (observation and 

potential consequences), technical analysis details (including databases, employed models, 

and methodologies), recommended actions and associated mission impacts, and flight closure 

rationale, if applicable. These steps are designed to eliminate the possibility of critical 

missteps by the MMT due to incomplete or un-communicated information. NASA has 

documented these changes in a new Mission Evaluation Room console handbook that 

includes MMT reporting requirements, a flight MMT reporting process for on-orbit vehicle 

inspection findings, and MMT meeting support procedures. 

Additional improvements were made to MMT internal processes and procedures, including 

more clearly defining requirements for MMT meeting frequency and the process for 

requesting an emergency MMT meeting. The MMT will hold meetings daily beginning at L-2 

or L-1 day, depending on the scheduled time of launch. The membership and organization of 

the preflight and flight MMT are standardized. In addition, the Space Shuttle Program Deputy 

Manager now chairs both phases of the MMT, preflight and flight. 

The MMT member’s responsibilities have been clearly defined, and MMT membership and 

training status for each mission is established by each participating organization in writing at 

the Flight Readiness Review (FRR). Each MMT member also has clearly defined processes 

for MMT support and problem reporting. 

Procedures for flight MMT meetings are standardized through the use of predefined templates 

for agenda formats, presentations, action item assignments, and readiness polls. This ensures 

that the communication and resolution of issues are performed in a consistent, rigorous 

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Final Report of the Return to Flight Task Group 

manner. Existing Space Shuttle Program meeting support infrastructure and a collaboration 

tool are used to ensure that critical data are distributed before scheduled meetings and that 

MMT meeting minutes are quickly distributed following each meeting. In addition, NASA 

established formal processes for the review of findings from ascent and on-orbit imagery 

analyses, post-launch hardware inspections, ascent reconstruction, and all other flight data 

reviews to ensure timely, effective reviews of key data by the MMT. 

Using recognized techniques for improving communications for critical decision making, 

NASA refurbished the Mission Management Team’s working space to provide increased 

seating and improved communications. 

Other enhancements include a videoteleconferencing capability, a multi-user 

collaboration tool, and a larger room to 

allow more subject matter experts and 

MMT members. A large C-shaped table 

now seats all members of the MMT and 

encourages open communication by 

eliminating a hierarchical seating 

arrangement. The MMT Command 

Center has been operational since the 

November 2004 MMT simulation to 

give the team time to adapt and learn 

how to use all of the new tools. 

3.11.3.1 Training 

All MMT members, except those serving exclusively in an advisory capacity and the 

Department of Defense Mission Support representative, are required to complete a minimum 

set of training requirements to attain initial qualification prior to performing MMT 

responsibilities. MMT members must also participate in an ongoing training program to 

maintain qualification status, which is renewed annually. Training records are maintained to 

ensure compliance with the new requirements. 

In addition, to ensure adequate backup personnel are available, at least two people will be 

trained to fill each MMT core position prior to return to flight. This will protect the integrity 

of the integrated MMT process against individuals’ inability to perform their role for any 

reason. Verification of each flight specific team will be presented at the appropriate FRR. 

The Space Shuttle Program published a formal MMT training plan (NSTS 07700, Volume II, 

Program Structure and Responsibilities, Book 2, Space Shuttle Program Directive 150) that 

defines the generic training requirements for MMT certification. This plan is comprised of 

three basic types of training: courses and workshops, MMT simulations, and self-instruction. 

Courses, workshops, and self-instruction materials were selected to strengthen individual 

expertise in human factors, critical decision making, and risk management of high-reliability 

systems. MMT training activities are well under way with several courses/workshops held at 

various NASA centers and 13 simulations completed, including an end-to-end contingency 

simulation and a simulation to address MMT actions related to Contingency Shuttle Crew 

Support (see Section 3.16, SSP-3). These simulations brought together the flight crew, flight 

control team, launch control team, engineering staff, outside agencies, and ISS and Space 

Shuttle MMT members to improve communication and teach better problem-recognition and 

decision-making skills. 

Quality assurance processes have been established to help monitor that MMT training 

requirements are met, sustained, and improved over time. Numerous channels have been 

opened to allow the real-time expression of concerns or dissent. The support teams, including 

contractors, have revised their processes to better serve the MMT and have trained to these 

The MMT 

conference room 

was refurbished with 

the addition of a 

large C-shaped table 

and multimedia 

capabilities to 

better facilitate 

communications 

between members. 

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Final Report of the Return to Flight Task Group 

new processes. Formal training objectives, evaluation processes, metrics, and a closed-loop 

lessons-learned system are now a part of MMT training. Independent external evaluators will 

continue to challenge the integrity of MMT training. The International Space Station and 

Space Shuttle MMTs have cross-trained and are improving the standardization of processes 

and communications. The development of NSTS 60540, STS-114 Operations Integration 

Plan for Thermal Protection System Assessment has greatly improved the real-time decisionmaking process concerning potential Orbiter Thermal Protection System damage (see Section 

2.2 of this report for a further discussion of the OIP). 

Risk management is now a major consideration at each MMT meeting. Each identified hazard 

is required to have a clear risk assessment performed and presented to the MMT so the 

appropriate risk-versus-risk tradeoffs can be discussed and decided upon. Supporting 

analyses, assumptions, issues, and ramifications are a part of this discussion. 

3.11.4 RTF TG Assessment 

Because of the central role played by the MMT during the last flight of Columbia, the Task 

Group conducted a great deal of fact-finding regarding this recommendation. Members 

attended the first “live” simulation on December 3-5, 2003, and additional sims on February 

11, 2004, April 2, 2004, November 16-19, 2004, February 28 through March 7, 2005, and 

May 4, 2005. A variety of meetings, classroom training, assessed evaluations, and training 

exercises were also attended by the Task Group members and staff. NASA submitted a 

closure package in November 2004, but after review the Task Group requested additional data 

and simulations, especially one that exercised consideration of Contingency Shuttle Crew 

Support. A revised closure package was submitted to the Task Group on March 7, 2005. The 

Task Group again requested to witness a simulation that demonstrated the complex riskversus-risk trades involved with the possibility of invoking the CSCS capability; this sim was 

finally held on May 4, 2005. 

NASA has developed a new training plan for the MMT. With the passage of time, the Task 

Group has been able to witness the implementation of most aspects of the plan. There have 

also been numerous simulations conducted to date including more than ten involving live, 

face-to-face exercises of various parts of the next mission. 

Some of the training protocols were initially developed without clear objectives and 

techniques to assess the quality of training. Similarly, the first simulations lacked clear 

objectives and evaluation criteria. Further, lessons learned from prior simulations were not 

incorporated in subsequent exercises. With a maturing training program, many of the earlier 

deficiencies have been corrected and the MMT Training Plan has been updated to reflect 

formal evaluation requirements. However, not all aspects of the enhanced role of the MMT 

have been exercised completely, such as the potential use of the CSCS option and a launchon-need rescue mission (STS-300) and the incorporation of all new sources of data and 

imagery. The MMT held a special simulation (sim #13) that included consideration of 

invoking the CSCS capability; most Task Group members in attendance were satisfied with 

the results. 

The various delays in launching STS-114 have allowed the MMT to further refine its 

procedures and have resulted in continual improvement. The Mission Management Team has 

made notable progress in addressing the accident board’s concerns, and NASA has 

demonstrated a commitment to continual MMT improvement. 

The RTF TG assessment of NASA’s actions was completed at the June 8, 2005, meeting. The 

intent of CAIB Recommendation 6.3-1 has been met. 

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3.11.5 RTF TG Observations 

The Task Group recognizes that the notable MMT improvements made to-date are a journey, 

not an end, and MMT processes and member training need to continue to grow and mature 

through the remaining missions of the Space Shuttle Program. In addition, NASA needs to 

ensure that the MMT and its support teams understand and have confidence in their ability to 

incorporate the latest analytical and engineering information available to them, to include the 

totally integrated risk assessment of the Space Shuttle system and its knowns, unknowns, 

limitations, uncertainties, and assumptions. Specific observations of areas that need continual 

improvement include: 

• NASA needs to continually grow and improve a systematic MMT training 

evaluation system which ensures that MMT training focuses on value, required 

knowledge, and the “science of learning.” The course content, simulation design 

and delivery, and self-instruction requirements must be continuously assessed 

and quality assurance plans rigorously applied. NASA should also consider 

formal MMT training on new and emerging capabilities, such as inspection, 

imagery, and CSCS. 

• Just as the MMT needs to adjust and improve with each “learning experience” 

(training or live), all of the documents supporting the MMT need to be 

continually updated and refined based on experience, need, and the evolving 

MMT decision-making capabilities. 

• The MMT needs to continue to improve and mature their integrated risk-versusrisk identification, assessment, decision making, and trades capabilities based on 

the latest available information and systems integration capabilities to guide 

them in their time-sensitive critical decisions. This includes the certainties and 

uncertainties that exist in the various analytical tools and models used by the 

MMT. Existing linear (i.e., non-integrated) decision making frameworks and the 

existing meeting agenda format need to be continually assessed and revised to 

meet the MMT’s needs. 

• In terms of the new, more rigorous training requirements, NASA also should 

recognize the opportunity to capitalize on the broader test and validation 

potentials of MMT simulations for other technical and operational capabilities 

beyond just the training of MMT members. 

• Post-Columbia, NASA senior leadership have new responsibilities in terms of 

MMT decision making and, during future MMT simulations need to ensure that 

MMT processes fully support their new Headquarters roles for time critical 

decisions and risk-versus-risk trades and periodically exercise them. Specific 

areas where NASA Headquarters senior leaders have new responsibilities 

include Safety and Mission Assurance, the Independent Technical Authority, 

and the potential decision to declare the need to implement the Contingency 

Shuttle Crew Support capability and its resulting launch-on-need rescue mission. 

• As a senior critical decision-making team, the MMT will continue to have 

unique insight into areas where there are critical information gaps, seams, 

unknowns, and uncertainties. The MMT can further serve NASA and the 

program by helping to point out these areas and prioritize them for focused 

closure. 

• Finally, the Task Group observes that NASA should consider formalizing 

periodic, independent oversight of the MMT to help sustain it as a “continuously 

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The Vehicle 

Assembly Building 

(VAB) at the 

Kennedy Space 

Center is one of the 

largest enclosed 

spaces in the world. 

The building was 

originally constructed 

as part of the Apollo 

moon program, and 

is currently used to 

stack the Space 

Shuttle vehicle. 

learning” entity for the remainder of the Space Shuttle Program. On at least an 

annual basis, an external entity should observe, evaluate (audit), and challenge 

the MMT’s ability to continuously improve, as well as evaluate MMT member 

certifications and training. 

While the Agency’s implementation of this recommendation has been serious and 

comprehensive, it will, by its very nature, remain a “work in progress” for the remaining 

missions of the Space Shuttle Program. Many lessons have been learned from the Columbia 

accident over the past 29 months, but with each mission many other lessons will also be 

learned. As stated previously, the fulfillment of R6.3-1 is a journey, not an end. 

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3.12 CAIB Recommendation 6.3-2 – 

National Imagery and Mapping Agency Memorandum of Agreement 

Modify the Memorandum of Agreement with the National Imagery and Mapping Agency to 

make the imaging of each Shuttle flight while on orbit a standard requirement. 

3.12.1 RTF TG Interpretation 

There was considerable public discussion of the decision during the flight of Columbia to 

forego requesting the assistance of other federal agencies in assessing the condition of the 

Orbiter. The Columbia Accident Investigation Board (CAIB) wanted the Space Shuttle 

Program to have the procedures in place to get all possible data to investigate a potential 

problem. This included having the proper personnel maintain the appropriate security 

clearances to access data from National assets. 

3.12.2 Background 

The National Imagery and Mapping Agency (NIMA) was created in 1996 by combining the 

mapping and imagery analysis efforts of the Central Intelligence Agency (CIA) and 

Department of Defense (DoD). On November 24, 2003, NIMA changed their name to 

the National Geospatial-Intelligence Agency (NGA) as dictated by the 2003 Defense 

Authorization Bill. 

National assets were available that potentially could 

have revealed the damage to Columbia while on orbit, 

but these assets were not used during the flight. NASA 

has previously used National assets to support the 

Space Shuttle Program, but the process and procedures 

to do so were overly complex and obscure. 

The CAIB found that the relationships between NASA 

and other Government agencies that could provide the 

assessment capabilities needed to be formalized and 

strengthened. Additionally, they recommended that 

such assessments should become a part of the standard 

mission requirements for each Space Shuttle flight, that all decision-makers within the Space 

Shuttle Program be made aware of the available capabilities, and that a small set of personnel 

maintain the appropriate security clearances and briefings. 

3.12.3 NASA Implementation 

The Memorandum of Agreement (MoA) with the National Imagery and Mapping Agency was 

modified in July 2003 as recommended by the CAIB. NASA has since worked with the full 

range of supporting agencies to develop an Interface Operations Agreement that maximized 

the use of available National assets to assist in on-orbit assessments. The NASA Standard 

Operating Procedures for requesting support from appropriate federal agencies were 

completed in December 2003 and have been exercised successfully. The capabilities have 

been, and will continue to be, demonstrated during MMT simulations. 

In order to fully comply with the CAIB recommendation, NASA has identified the positions 

that require access to classified data and will ensure that all NASA personnel involved in 

human space flight are familiar with the general capabilities available for on-orbit vehicle 

assessments and the procedures to request and process such assessments. NASA has also put 

in place secure data transmission systems and procedures for the dissemination of classified 

information to the NASA Space Operations Mission Directorate field centers. 

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Discovery in the 

Vehicle Assembly 

Building transfer 

aisle, ready to be 

lifted to the vertical 

position in 

preparation for 

mating with the 

External Tank and 

Solid Rocket 

Boosters. 

Final implementation details have been worked out in a lower level memorandum of 

understanding. Since this action may involve receipt and handling of classified information, 

the appropriate security safeguards will be observed during its implementation. 

Although these actions address the recommendation found in CAIB R6.3-2, NASA has taken 

additional appropriate actions with other federal agencies to maximize use of National assets 

for all flight segments. NASA has teamed with the Department of Defense and the 

intelligence community to develop new agreements and operating procedures to obtain 

support from the partnering agencies. 

3.12.4 RTF TG Assessment 

Fact-finding meetings were attended by the Task Group on December 8, 2003, and February 

18-19, 2004, where the Memorandum of Agreement with the NGA was discussed. The next 

lower-level Interface Operating Agreement that details the methods for NASA to obtain 

information, and how that classified information would be handled within NASA were also 

discussed. The detailed plans and agreements themselves are classified due to the nature of 

National assets they discuss. 

The Task Group’s initial evaluation of NASA’s actions was completed at the April 16, 2004, 

teleconference plenary where the assessment was conditionally closed. The conditions 

required that NASA present the results of an integrated simulation that exercised the NGA 

MoA for assessment by the RTF TG. After receiving additional information from NASA, the 

assessment was closed at the December 16, 2004, plenary meeting. The intent of CAIB 

Recommendation 6.3-2 has been met. 

3.12.5 RTF TG Observations 

The Task Group believes that NASA should periodically review the Memorandum of 

Agreement with the National Geospatial-Intelligence Agency, assess the capabilities of the 

NGA and other agencies, and ensure that the appropriate security clearances are maintained 

within NASA to exploit these capabilities as necessary. In addition, this capability should also 

be periodically exercised during MMT simulations. 

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Final Report of the Return to Flight Task Group 

3.13 CAIB Recommendation 6.4-1 – 

Thermal Protection System Inspection and Repair 

For missions to the International Space Station, develop a practicable capability to inspect 

and effect emergency repairs to the widest possible range of damage to the Thermal 

Protection System, including both tile and Reinforced Carbon-Carbon, taking advantage of 

the additional capabilities available when near to or docked at the International Space 

Station. 

For non-Station missions, develop a comprehensive autonomous (independent of Station) 

inspection and repair capability to cover the widest possible range of damage scenarios. 

Accomplish an on-orbit Thermal Protection System inspection, using appropriate assets and 

capabilities, early in all missions. 

The ultimate objective should be a fully autonomous capability for all missions to address the 

possibility that an International Space Station mission fails to achieve the correct orbit, fails 

to dock successfully, or is damaged during or after undocking. 

3.13.1 RTF TG Interpretation 

Based on a majority opinion of the members, the Task Group revised its interpretation of this 

CAIB recommendation at the June 27, 2005 meeting. The interpretation that the final 

assessment was based on follows: 

CAIB Recommendation 6.4-1 consists of four separate provisions. Although the 

entire recommendation is labeled Return to Flight, the second and fourth provisions 

do not apply to STS-114. These provisions are not being considered by NASA or the 

Task Group. If a non-ISS mission, such as Hubble Space Telescope (HST) Service 

Mission 4, is added to the flight manifest, the ASAP should review this 

recommendation. 

NASA must define any damage to tile and RCC that poses an unacceptable hazard to 

the Orbiter and crew during entry, and be able to detect the location and extent of 

such damage. Assessment of NASA’s on-orbit TPS inspection capability is covered 

in Recommendation 3.4-3 

Each of the repair options in the suite of options that constitutes the repair capability 

must be have completed formal design reviews, ground verification testing, 

procedure development and an integrated Design Certification Review such that 

NASA could implement it in an emergency situation with confidence that it would 

behave as expected 

3.13.2 Background 

The Columbia accident clearly demonstrated that the Orbiter Thermal Protection System, 

including the reinforced carbon-carbon (RCC) panels and acreage tiles, was vulnerable to 

impact damage from the existing debris environment. As a result, the Columbia Accident 

Investigation Board (CAIB) issued recommendations to eliminate debris (R3.2-1), determine 

the structural integrity of the RCC (R3.3-1), harden the Orbiter (R3.3-2) against impacts, and 

to develop on-orbit repair capabilities (R6.4-1). 

The concept of a “tile repair kit” is hardly new. Such a kit was originally intended to be flown 

aboard STS-1 and work was undertaken by NASA and its contractors, particularly Martin 

Marietta. However, as the launch of STS-1 approached, the development effort was cancelled 

Page 85 of 216 
Final Report of the Return to Flight Task Group 

A computergenerated image of 

the OBSS in 

operation while 

attached to the 

Shuttle Remote 

Manipulator System. 

The OBSS is 

capable of inspecting 

all of the RCC on the 

Orbiter, as well as 

the majority of the 

tiles on the 

underside of the 

vehicle. 

due to a variety of technical problems and a renewed confidence in the tiles themselves. At 

the time, the RCC was considered particularly resilient and there was little thought given to a 

repair capability; as later events demonstrated, this assumption was incorrect. 

3.13.3 NASA Implementation 

Note: This section refers to inspection and repair during missions to the ISS. 

NASA has expanded the capabilities to detect debris liberated during ascent, to locate where 

debris may have originated, and to identify impact sites on the Orbiter Thermal Protection 

System for detailed evaluation. Methods to access the Orbiter for possible repair have been 

evaluated and procedures developed and trained. In addition, five repair techniques have been 

selected to be carried on STS-114. 

These capabilities, paired with NASA’s improved insight into the impact and damage 

tolerance of the Orbiter, will allow the Mission Management Team (MMT) to make informed 

decisions about whether any impacts sustained represent a threat to mission success or the 

safety of the crew and the vehicle. They will also help to determine whether any repairs that 

are attempted are successful. 

3.13.3.1 Inspection 

NASA will use a combination of Space Shuttle and International Space Station assets to 

evaluate the Orbiter Thermal Protection System and identify and characterize whether damage 

was sustained during ascent. These inspection assets and methods include the Orbiter Boom 

Sensor System (OBSS), the R-Bar Pitch Maneuver, the Shuttle Remote Manipulator System 

(SRMS), the Space Station Remote Manipulator System (SSRMS), and an experimental wing 

leading edge impact detection system. Each inspection method provides a piece of 

information to improve insight into the conditions of the Orbiter Thermal Protection System. 

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Final Report of the Return to Flight Task Group 

3.13.3.1.1 Orbiter Boom Sensor System 

The OBSS is an imaging system that consists of two sensor packages on the end of a 50-footlong boom structure. The boom is carried on the starboard sill of the Orbiter payload bay 

(which had originally been configured to carry a second remote manipulator system arm if 

needed) and is used in conjunction with the Shuttle Remote Manipulator System (SRMS) 

carried on the port sill. The OBSS carries a laser camera system (LCS) and a laser dynamic 

range imager (LDRI) that downlink data via the Orbiter communications system. The data 

will be processed and analyzed on the ground as part of the Thermal Protection System 

assessment process. The OBSS is the primary system used to inspect the wing leading edge 

and nosecap RCC, and also to obtain detailed depth measurements of damaged areas. In 

addition, the OBSS has the capability to support a crewmember in foot restraints if needed to 

perform inspection or repair during extra-vehicular activities (EVA). 

On flight day 2, prior to docking with the ISS, the crew will use the OBSS to inspect the 

nosecap and the underside and apex of the 22 leading edge RCC panels on each wing. If any 

evidence of a debris strike exists, the OBSS instruments will be used during flight day 4 for 

more detailed inspections of specific areas. 

3.13.3.1.2 ISS Imagery during the R-bar Pitch Maneuver 

The primary method of inspecting the acreage tile on the bottom of the Orbiter consists of 

imagery taken by the ISS crew as the Orbiter approaches for docking. This approach, called 

the R-Bar Pitch Maneuver, has been practiced by Space Shuttle flight crews in the simulator. 

When the Orbiter is 600 feet away from the ISS, it will pause its approach and pitch-over to 

present its underside to the station. The ISS crew will take overlapping high-resolution digital 

still images of the acreage tiles and downlink them to the ground. Areas of concern will be reinspected for more detail (such as damage depth) while the Orbiter is docked to the ISS. 

The cameras used during the R-Bar Pitch Maneuver have the capability to detect critical 

damage in all areas of the Orbiter Thermal Protection System tile. Analysis indicates that the 

photos taken with a 400mm lens have an analytical resolution of 3 inches on normal surfaces; 

the 800mm lens provides a 1-inch analytical resolution. 

3.13.3.1.3 Other Imagery Assets 

Other imagery assets include the cameras on SRMS, the SSRMS, and digital camera assets on 

board the Orbiter or the ISS. The SRMS and SSRMS can inspect areas of the Orbiter Thermal 

Protection System within their reach, such as the crew cabin area, forward lower surface, and 

vertical tail, using their closed circuit television camera systems. Other assets include the still 

cameras available to EVA crewmembers in the event an EVA inspection is required to do 

focused inspection of areas that may have suspected damage. These alternate inspection 

methods are not pre-planned, and will be used as a backup for the other inspection methods. 

3.13.3.1.4 Wing Leading Edge Impact Detection System 

The wing leading edge impact detection system was developed from an existing technology 

that had been previously flown as an experiment in the Orbiter aft fuselage. Initially, NASA 

hoped to include the wing leading edge sensors as a key element to detect damage. However, 

this system has not been flight-tested in this environment, so its actual capability is yet to be 

determined. For STS-114, these sensors will be used primarily to “point” to areas of the wing 

leading edge needing further inspection by the OBSS. 

The wing leading edge impact detection system is composed of accelerometer and 

temperature sensors attached to the wing spar behind the reinforced carbon-carbon panels. 

Page 87 of 216 
Final Report of the Return to Flight Task Group 

These battery-powered sensors transmit data via RF to receivers in the Orbiter. The data are 

collected during ascent and downlinked to the ground via the Orbiter communications system 

once on-orbit to help identify possible debris impact areas on the wing leading edge RCC 

panels. In the event an impact is detected, engineers can determine the location of the 

sensor(s) that measured the impact and, through the TPS assessment process, recommend a 

more focused inspection of the suspect area later in the mission. Due to the limited battery life 

in the current implementation, there is a finite period of time for collection and transfer of 

impact data using this system. In the future, the power source will be changed from batteries 

to the Orbiter’s main electrical systems, allowing the sensor system to provide impact 

detection throughout the mission. 

3.13.3.2 Repair 

Despite extensive efforts to develop TPS materials and techniques, the state-of-the-art in this 

area has yielded little technology to support the concept. As a result, continued effort does not 

hold promise of significant capabilities beyond those in hand. While a vehicle-wide TPS 

repair capability is not a constraint to the return to flight, STS-114 will carry a limited number 

of experimental materials and tools to repair minor tile damage and small- to medium-sized 

RCC damage in an emergency. 

Marker 

Feeler 

Gauge 

Drill/Reamer 

Plug Installation 

Tool 

Scraper 

Bag Pallet 

Probe 

Gauge 

Plug 

Plate 

tools are being 

panels becomes 

Transfer 

Temperature 

NOAX 

Applicator 

NOAX 

Cartridge 

Protuberance 

Attachment 

Cover 

A variety of special 

carried aboard 

STS-114 and future 

flights in case repairs 

to the reinforced 

carbon-carbon 

necessary. 

To effect repairs, the EVA crew will use either the SRMS or the SSRMS to gain access to 

locations on the Orbiter; when necessary, they may also use the OBSS. NASA has also develPage 88 of 216 
Final Report of the Return to Flight Task Group 

oped a combined SRMS and SSRMS “flip around” operation, called the Orbiter Repair 

Maneuver (ORM), to allow TPS repairs while the Orbiter is docked to the ISS. The ORM 

involves turning the Orbiter into a belly-up position that allows the SSRMS to position an 

EVA crewmember to reach any TPS surface needing repair. The procedure is feasible until 

later flights when the ISS grapple fixture required to support this maneuver will be blocked, 

and new TPS repair access techniques will need to be developed. 

3.13.3.2.1 RCC Repair 

NASA has evaluated RCC repair concepts with participation from six NASA Centers, 11 

contractors, and the United States Air Force Research Laboratory. The main challenges to 

repairing RCC are maintaining a bond to the RCC coating during entry heating and meeting 

stringent aerodynamic requirements for repair patches and fills. NASA is investigating two 

complementary repair concepts – plug and crack – that together could, in the future, allow the 

emergency repair of limited RCC damage. Both concepts have limitations in terms of damage 

characteristics, damage location, and amount of testing and analysis completed to-date. 

NOAX 

Non-Oxide Adhesive eXperimental sealant (NOAX) is a pre-ceramic polymer sealant 

intended to repair cracks up to 0.065-inch-wide by 9-inches-long, and small areas (1-inch at 

the outer mold line and 2-inches at the inner mold line) of coating loss on any Orbiter RCC 

panel. Curing NOAX requires a heater, adding significant complication to its use on-orbit; 

however, uncured NOAX has recently passed arc-jet tests, leading to a decision not to use the 

heater to cure the material. NOAX has been shown to 

be successful in repairing cracks in ground tests but 

process controls will be more challenging in the EVA 

environment. At this time, there is uncertainty 

concerning the microgravity behavior of the material, 

and there is limited ground testing on real RCC 

substrate with realistic damage. This technology will be 

tested during an EVA development test objective 

(DTO) on STS-114. 

Plug Repair 

The plug repair is intended for small to medium-size 

holes in some areas of the wing leading edge RCC. A 

flexible carbon-silicon carbide (C-SiC) cover plate is 

held in place with a SiC-coated TZM toggle bolt and 

sealed around the edges with NOAX. Each plug cover 

plate might repair up to a 4-inch-diameter hole (major 

dimension) with a 1-inch surrounding spalled area. If 

the existing hole is less than 1-inch diameter, a drill 

will be used to enlarge the hole in order to insert the 

toggle bolt. A dozen different cover plates with various 

curvatures are available and provide coverage for 62­

percent of the wing leading edge RCC areas. Although 

arc-jet testing indicates that the material can withstand 

entry, there are concerns about the bolt fracturing if the 

SiC coating is scratched. There are also concerns about 

drilling through RCC to insert the plug, especially if 

there is not a preexisting hole. A middeck DTO on the 

mechanical function of this repair capability, excluding 

drilling, will be performed on STS-114. 

The plug repair starts 

with either a 

pre-existing hole in 

an RCC panel, or 

with the astronaut 

drilling a hole. A 

toggle bolt is 

inserted through the 

hole to hold the 

carbon-silicone 

carbide cover in 

place. NOAX is used 

around the edge as 

a sealant. 

Page 89 of 216 
Final Report of the Return to Flight Task Group 

3.13.3.2.2 Tile Repair 

A limited tile repair capability will be ready for on-orbit testing on STS-114. On this flight, 

NASA plans to demonstrate the emittance wash technique during an EVA, fly two Cure-InPlace Ablator (CIPA) applicators (that will not be demonstrated) that could repair tile 

damage, and fly a mechanical overlay (also not demonstrated) that could potentially repair 

larger areas of damage in the acreage tiles. 

A hand-held 

extrusion gun is 

used to apply the 

emmitance wash. 

The CIPA hardware 

is much more 

involved, with most 

components 

contained on a 

backpack that fits 

over the EVA suit. 

Emittance Wash 

Emittance wash, a silicon carbide (SiC) 

material mixed with a carrier, is expected to be 

effective for shallow tile damage on any black 

tile surface. While initially developed as a 

surface preparation for the CIPA technique, 

NASA determined the material has a standalone repair potential. Emittance wash 

partially restores the emissivity of damaged 

tile surface to increase heat rejection through 

radiation, and is used to prevent small gouges 

in the tile from becoming deeper holes. The 

material is applied using an extrusion gun. 

Arc-jet tests are continuing to gather data on 

the thermal performance of a repair using this 

technique; however, thermal performance 

testing will be limited before STS-114. 

Cure-in-Place Ablator (CIPA) 

Two CIPA applicators will be carried aboard 

STS-114, potentially allowing repair of tile 

damage sites anywhere on the Orbiter except a 

small number of LI-2200 tiles. The CIPA 

material, called STA-54, is a two-part room 

temperature material that is applied with a 

pneumatic dispenser gun that mixes the two 

parts within the dispenser. Ancillary tools 

include emittance wash to prime the surface, 

gel and foam brushes to clean the surface, 

stamps to shape the material, a contour gage to 

measure the material surface relative to the 

outer mold line, and a durometer to test 

hardness. The CIPA “goo” is intended for use 

in deeper tile damage in areas up to 10 by 20 

inches. If a CIPA repair is attempted, a second 

EVA will be required to inspect the repair and 

test the hardness. This information along with 

photographs of a dissected “test bead” created 

at the same time as the repair are required to 

assess the integrity of the repair for entry. The 

quality of the repair appears to be highly 

operator dependent. 

There have been multiple technical difficulties 

in the development of the CIPA materials and 

application tools. Most significant of these is 

Page 90 of 216 
Final Report of the Return to Flight Task Group 

recurrent bubbling in the STA-54. NASA has been unable to determine the root cause of the 

bubbling, or to adequately and consistently characterize its severity. Additionally, there 

remain several areas of uncertainty about the material properties of STS-54, including its 

ability to cure during the thermal cycling of Earth orbit and its adhesion to tile during entry, 

since tile and STA-54 have different thermal expansion coefficients. 

Though somewhat unpredictable, bubbling of the material has been shown in arc-jet testing to 

be less important in the ability to protect the Orbiter than originally thought, but testing in the 

actual on-orbit environment is necessary to confirm this finding. Analytical models for CIPA 

repair assessment are uncorrelated with test data, and if the material is used as an emergency 

repair on STS-114, formal validation testing to material performance requirements will be 

limited to real time arc-jets test. 

Another issue concerns the level of toxicity of one of the STA-54 components prior to mixing 

and dispensing. At this time the program is pursuing a triple level of containment – a common 

toxicity mitigation technique – for STA-54 stowage and is assessing the crew risk during 

EVA use for the STS-121 development test objective or if needed for tile repair. 

Tile Overlay 

The mechanical overlay repair is performed by 

filling the damaged tile cavity with a Saffil 

batting insulation, then placing a thin C-SiC 

cover plate and high-temperature gasket seal 

over the damaged tile area. SiC-coated ceramic 

augers (screws) with accompanying SiC-coated 

ceramic washers are screwed into undamaged 

tiles to attach the overlay. The 12-inch by 

25-inch overlay is capable of covering a 10-inch 

by 20-inch damage area. While this technology 

is being carried as a contingency on STS-114, its 

testing is very immature at this time. However, 

development testing is on a fast track and NASA 

believes this option appears to be promising. 

The tile overlay repair 

is a metallic sheet that 

is screwed in place 

over the damaged tiles 

after the cavity is filled 

with Saffil batting 

insulation. 

3.13.3.3 TPS Damage Assessment 

The Space Shuttle Program has developed a substantial knowledge-base of the vulnerabilities 

of both tile and RCC, and the level of damage that testing to date indicates could be sustained 

without unacceptable risk during entry. This knowledge is essential for decision-making in the 

event that on-orbit inspection reveals damage to the TPS. Critical damage size has been 

defined and is highly location dependent. NASA has incorporated the experimental data 

gleaned over the last year to create a “critical damage map” that reflects the best 

understanding to date. For RCC, critical damage in the most vulnerable areas is a 0.020-inchwide crack or a 0.08-inch (major dimension) coating loss. A 1-inch (major dimension) gouge 

around the main landing gear door seals or ET umbilical door seals, or a 3-inch gouge in 

acreage tile represents critical tile damage. If damage exceeding these dimensions is detected, 

reducing Orbiter weight, altering the entry profile, reducing landing sink rate, and other 

options will be considered, along with or in lieu of repair, to achieve an acceptable condition 

for entry. The decision to land an Orbiter with an untested repair will require a difficult 

decision based on models, experimental runs in the arc-jet, and flight history of the thermal 

environment during the entry. The OIP companion document, NSTS 60540-ANX1 Orbiter 

Damage Assessment Process Annex, describes the teams, tools, and processes that will be 

used to transform data from the TPS assessment teams into information that can be used about 

the condition of the TPS at multiple milestones during flight by program leadership to make a 

timely entry readiness, repair, or Contingency Shuttle Crew Support determination. 

Page 91 of 216 
Final Report of the Return to Flight Task Group 

3.13.4 RTF TG Assessment 

The Orbiter Thermal Protection System was never intended to be repaired on-orbit. Various 

repair capabilities were explored early during Space Shuttle development and again more 

recently, but it is highly unlikely that a comprehensive repair capability for all possible 

damage will become available for the remaining flights of the Space Shuttle Program. Tile 

and RCC repair have proven to be far more challenging than either the CAIB or NASA 

understood two years ago. Enormous effort has been expended in search of effective and 

operationally feasible repair capabilities, and far more is known today than before about the 

capabilities and vulnerabilities of the Orbiter Thermal Protection System. Nevertheless, the 

program is far from having a certifiable capability. Several innovative repair solutions for a 

limited range of potential damage are aggressively being pursued. Five such limited repair 

options will be carried on STS-114; however, much more testing and evaluation remain to be 

done. The options proposed by NASA have not yet achieved a level of maturity that the Task 

Group considers necessary to be defined as a capability and thus the intent of this 

recommendation has not been met. 

3.13.4.1 Inspection 

The two primary methods to be used on-orbit for critical inspection of Orbiter Thermal 

Protection System, the OBSS sensor suite and R-Bar Pitch Maneuver have been assessed as 

part the Task Group’s evaluation of CAIB Recommendation 3.4-3, High-Resolution Imagery 

of Orbiter. That recommendation was closed on June 8, 2005 (see Section 3.6 of this report). 

Data from the wing leading edge impact detection system will be used as corroborating 

evidence with imagery data to provide focus for on-orbit inspection. The limited data that will 

be available due to short battery life, together with the experimental nature of this system, 

mandate that no critical decisions be based on the data from this system. 

The Task Group supports use of numerous other sources of ground and airborne imagery 

during launch and ascent to provide views of the External Tanks and Orbiter which serve as 

pointers for focused inspection of the Orbiter by the OBSS. All these capabilities together 

should assure a comprehensive and successful inspection. 

3.13.4.2 Repair Technologies 

Although NASA has determined, and accepted the risk, that the repair capability called for in 

CAIB Recommendation 6.4-1 is not a constraint to launch of STS-114, the Space Shuttle 

Program intends to provide the STS-114 crew with the best available options. An enormous 

amount of work on both tile and RCC repair has resulted in five experimental repair 

techniques. None of these techniques will be certified for STS-114; some may never be 

certified because they are too operator dependent. As NASA stated in the May 2005 version 

of the Integrated Risk Acceptance Approach for Return to Flight – “Until a verifiable, reliable 

Thermal Protection System repair technique for tile and reinforced carbon-carbon components 

is in hand, we will have limited, best effort capabilities to apply when needed.” 

While it is prudent to manifest repair materials and hardware on STS-114 to be used only if 

the Orbiter cannot otherwise make a safe entry, extreme caution must be exercised when use 

of these materials and hardware might further exacerbate the risk to Orbiter and crew beyond 

the risk due to the initial Thermal Protection System damage. In particular, the RCC plug and 

tile overlay repairs require additional holes to be bored into the Thermal Protection System, 

and CIPA and NOAX can each create an additional hazard if the material expands beyond the 

Orbiter outer mold line. Each option carries its own risks. For STS-114, should a damage 

situation require use of any repair technique, the Mission Management Team and NASA 

leadership will confront extremely complex and difficult risk-versus-risk trades given the 

unknowns and uncertainties within and between inspection, repair, and rescue options. 

Page 92 of 216 
Final Report of the Return to Flight Task Group 

3.13.4.3 TPS Damage Assessment 

The Task Group believes that it is just as important to be able to decide when not to repair as 

it is when to attempt a repair, especially when the repair capabilities are unproven. The 

“critical damage maps,” although certified for preflight, continue to evolve to reduce the 

likelihood of making unnecessary repairs. The NASA Engineering Safety Center (NESC) 

peer review of critical tile damage models is an important milestone to be achieved prior to 

STS-114; a preliminary draft was available to the Task Group during this assessment. The 

addition of the peer review provides added confidence in the accuracy of these models. 

The Mission Operations Directorate has defined several alternate scenarios to minimize entry 

heating that will be available should they be required. A number of procedures in various 

stages of maturity can be uplinked so that the crew can make these adjustments. 

Because they will be collecting significant volumes of data on the condition of the TPS, much 

of which will be new to the ground operations team, the Task Group fully supports the 

development of NSTS 6054, STS-114 Operations Integration Plan for Thermal Protection 

System Assessment (the OIP) and it associated Damage Assessment Annex to govern the use 

of all these data in the decision-making process on the health of the Orbiter Thermal 

Protection System and the potential need to repair damage, execute other operational risk 

reduction strategies, or fly home with the expectation that the damage is not large enough to 

be considered critical. See Section 2.2 of this report for a further discussion of the OIP. 

3.13.4.4 Conclusion 

In the May 2005 Integrated Risk Assessment Approach for Return to Flight, NASA 

acknowledges that External Tank debris allowables currently do not protect against 

catastrophic damage to the Orbiter Thermal Protection System. Therefore the goal of 

demonstrating that the Orbiter Thermal Protection System can withstand impact from any 

debris which may be released from the External Tank or other flight elements has not been 

met. Nor can the repair options manifested on STS-114, even if they were certified, repair the 

range of damage that could occur. There is a gap between possible debris liberation and the 

ability of Orbiter Thermal protection System to withstand impact and to repair damage. 

The Task Group has reached the conclusion that the five experimental repair options 

manifested on STS-114 show promise for future flights, but are contingency measures rather 

than practicable repair capabilities at this time. Even though all Orbiter Thermal Protection 

System repair techniques being considered are only for emergency use and cover a limited 

range of potential damage, they can and should go through a rigorous design and certification 

process; to date, none of the tile or RCC repair techniques have gone through this process. 

Therefore, the Task Group does not consider tile and RCC repair techniques sufficiently 

mature to be a practicable repair capability for STS-114. 

As assessed in Section 3.6 (R3.4-3), the inspection techniques planned for STS-114 provide 

high resolution capability and significantly enhance the ability to view possible damage. 

Resources available via National assets (R6.3-2) add to this capability. Therefore, NASA has 

satisfied the inspection portion of this recommendation. 

The RTF TG assessment of NASA’s actions was completed at the June 27, 2005, meeting. 

Despite extensive efforts on the part of the Tile Repair Project and RCC Repair Project to 

develop a practicable Thermal Protection System repair capability, the majority of the Task 

Group believes that the intent of CAIB Recommendation 6.4-1 has not been met. 

Page 93 of 216 
Final Report of the Return to Flight Task Group 

Discovery, with Earth 

as a backdrop, 

performs the R-bar 

Pitch Maneuver as 

she approaches the 

International Space 

Station. The crew of 

the ISS takes 

high-resolution 

photographs of the 

Orbiter during this 

maneuver to allow 

ground-based 

analysts to 

determine if there is 

any damage to the 

Orbiter Thermal 

Protection System. 

3.13.5 RTF TG Observation 

The RTF TG believes that the repair portion of R6.4-1 presented an extreme technical 

challenge to NASA given the physical characteristics of the Orbiter Thermal Protection 

System. Repairs to TPS damage of the magnitude suffered by Columbia are not considered 

feasible with current technology; however, modifications to the External Tank should 

preclude that type of damage from occurring in the future. 

3.13.6 RTF TG Minority Opinion on CAIB Recommendation 6.4-1 

Much of the discussion among Task Group members has centered on the definition of the 

words “practicable capability.” While Task Group members agree that a practicable capability 

must be “feasible, able to be accomplished,” we cannot agree on the level to which a task 

must be developed before it becomes a “capability.” The minority opinion of the Task Group 

is that a repair technique is a capability if it can actually be performed on orbit and has been 

shown to be able to withstand the heat of entry, which is its intended purpose. 

There has been further discussion around the accident board’s intent when they used the 

words “widest possible range of damage.” Multiple conversations with several members of 

the CAIB, including those most closely associated with the writing of this recommendation 

indicate a clear intent of those words to be “to the widest possible damage that NASA can 

accomplish.” Thus, the fact that NASA does not yet have coverage for 100 percent of the 

Orbiter Thermal Protection System does not preclude compliance with the intent of the 

recommendation. 

While much more testing is necessary to increase the confidence in the repairs and to certify 

them, the repair capabilities are a far cry from the notion outlined for the CAIB that amounted 

to stuffing tools and water-filled baggies into the wing leading edge while dangling from a 

ladder hanging from the payload bay doors (CAIB, Vol. I, p. 173). The use of the crew in the 

development of the operations associated with the repair techniques, coupled with multiple 

training sessions using the standard environments to prepare for EVA operations, have 

resulted in repair techniques that can be put into practice should the need arise. MMT and 

component simulations have shown a willingness of the community to attempt a repair should 

one be deemed necessary, and upon successful completion of that repair, evaluated using set 

criteria, a willingness to bring the Orbiter and crew home rather than commit to a CSCS and 

attempt to launch a second vehicle. 

The minority opinion of the RTF TG is that this is what the CAIB intended when writing 

Recommendation 6.4-1. Therefore, it is the minority opinion of the Task Group that the intent 

of CAIB Recommendation 6.4-1 has been met. 

Page 94 of 216 
Final Report of the Return to Flight Task Group 

3.14 CAIB Recommendation 9.1-1 – 

Detailed Plan for Organizational Change 

Prepare a detailed plan for defining, establishing, transitioning, and implementing an 

independent Technical Engineering Authority, independent safety program, and a 

reorganized Space Shuttle Integration Office as described in R7.5-1, R7.5-2, and R7.5-3. In 

addition, NASA should submit annual reports to Congress, as part of the budget review 

process, on its implementation activities. 

R7.5-1 Establish an independent Technical Engineering Authority that is

responsible for technical requirements and all waivers to them, and will

build a disciplined, systematic approach to identifying, analyzing, and 

controlling hazards throughout the life cycle of the Shuttle System. The 

independent technical authority does the following as a minimum: 

• Develop and maintain technical standards for all Space Shuttle 

Program projects and elements 

• Be the sole waiver-granting authority for all technical standards 

• Conduct trend and risk analysis at the sub-system, system, and 

enterprise levels 

• Own the failure mode, effects analysis and hazard reporting 

systems 

• Conduct integrated hazard analysis 

• Decide what is and is not an anomalous event 

• Independently verify launch readiness 

• Approves the provisions of the recertification program called for 

in Recommendation R9.2-1 

The Technical Engineering Authority should be funded directly from NASA 

Headquarters and should have no connection to or responsibility for 

schedule or program cost. 

R7.5-2 NASA Headquarters Office of Safety and Mission Assurance should have 

direct line authority over the entire Space Shuttle Program safety

organization and should be independently resourced. 

R7.5-3 Reorganize the Space Shuttle Integration Office to make it capable of

integrating all elements of the Space Shuttle Program, including the 

Orbiter. 

3.14.1 RTF TG Interpretation 

The Columbia Accident Investigation Board (CAIB) expected NASA to return to flight 

relatively quickly, and did not want to restrict this activity by requiring major organizational 

changes. Instead, the CAIB wrote a separate recommendation that NASA produce a detailed 

plan on how the Agency would implement organizational changes embodied in three other 

recommendations (R7.5-1, Independent Technical Authority; R7.5-2, Safety and Mission 

Assurance; and R7.5-3, Systems Engineering and Integration). 

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However, preparations for the first return-to-flight mission took longer than initially expected, 

and NASA proceeded to implement the three specific organizational recommendations of the 

CAIB; the Task Group elected to evaluate the actual changes, although the final assessment 

was based only on the required plan. 

The CAIB used the term “culture” throughout its report, although there was not a specific 

recommendation (RTF or otherwise) to change NASA culture. Nonetheless, numerous CAIB 

findings and observations strongly emphasize leadership, managerial, training, and 

organizational issues that require immediate and serious attention. Within the parameters of 

the RTF TG charter, the Task Group did not specifically address these CAIB “culture” 

concerns, and the Task Group did not assess the studies ongoing within NASA pertaining to 

culture issues. Nonetheless, NASA has elected to implement an Agency-wide response to 

R9.1-1 through a document entitled “NASA Plan for Implementing Safe and Reliable 

Operations” (referred to as the “9.1-1 Plan”). 

Many of the CAIB organization observations are reflected in R7.5-1. The CAIB observed 

critical technical requirements were routinely waived and concluded the inherent conflicts of 

schedule, cost, and safety – the balance for which resided essentially with the Space Shuttle 

Program Manager – needed to be separated to provide an independent safety consideration. 

In regards to R7.5-2, the CAIB observed various parts of NASA were nominally responsible 

for “safety;” each NASA Center has safety organizations; each NASA program, including the 

Space Shuttle Program, has designated individuals responsible for safety; and NASA has an 

Office of Safety and Mission Assurance at Headquarters. This recommendation was intended 

to create clear lines of authority, responsibility, and communication, and help ensure 

independence by moving funding from NASA Centers and programs to NASA Headquarters. 

The CAIB found several aspects of Space Shuttle operations it believed to be suffering from 

incomplete integration, prompting them to write R7.5-3. Perhaps the most glaring was the 

apparent division of responsibility for addressing the separation of foam from the External 

Tank. Simplistically stated, the Orbiter Project thought it was up to those responsible for the 

tank to stop the shedding; the External Tank Project assumed the shedding occurring was not 

injurious to the Orbiter because no one told them otherwise. 

3.14.2 Background 

The accident board’s independent investigation revealed numerous areas in NASA’s 

organization and its operations requiring substantial improvement before returning the Space 

Shuttle to safe and reliable flight operations. The CAIB report specifically called for a 

detailed plan prior to the return to flight on three fundamental changes that NASA needed to 

make to improve the safety and reliability of its operations: 

• Restore specific engineering technical authority, independent of programmatic 

decision-making. 

• Increase authority, independence, and capability of the Safety and Mission

Assurance (SMA) organizations. 

• Expand the role of the Space Shuttle Integration Office to address the entire 

Space Shuttle system, not just propulsive elements. 

3.14.3 NASA Implementation 

Once a plan for CAIB Recommendation 9.1-1 had been developed, NASA proceeded toward 

implementation. 

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3.14.3.1 Independent Technical Authority (R7.5-1) 

The NASA Chief Engineer, as the Independent Technical Authority, governs and is 

accountable for technical decisions affecting safe and reliable operations. The Independent 

Technical Authority provides technical decisions for safe and reliable operations in support of 

mission development activities and programs and projects that pose minimum reasonable risk 

to astronauts, the NASA workforce, and the public. Sound technical requirements necessary 

for safe and reliable operations will not be compromised by programmatic constraints, 

including cost and schedule. 

The Independent Technical Authority is also working to strengthen the technical conscience 

throughout the engineering community, that is, personal responsibility to provide safe 

technical products coupled with an awareness of avenues available to raise and resolve 

technical concerns. Technical authority and technical conscience represent a renewed culture 

in NASA governing and upholding sound technical decision-making by personnel who are 

independent of programmatic processes. This change affects how technical requirements are 

established and maintained as well as how technical decisions are made, safety considerations 

being first and foremost in technical decision-making. Five key principles govern the 

Independent Technical Authority. This authority: 

1. Resides in an individual, not an organization; 

2. Is clear and unambiguous regarding authority, responsibility, and accountability; 

3. Is independent of Program Management; 

4. Is executed using credible personnel, technical requirements, and decisionmaking tools; and 

5. Makes and influences technical decisions through prestige, visibility, and the 

strength of technical requirements and evaluations. 

3.14.3.1.1 Warrant System 

The Chief Engineer has put technical authority into practice through a system of governing 

warrants issued to individuals. These Technical Warrant Holders (TWH) are proven subject 

matter experts with mature judgment who are operating with an Independent Technical 

Authority budget that is separate from program budgets and program authority. This 

Independent Technical Authority budget covers the cost of the Technical Warrant Holders 

and their agents as they execute their responsibility for establishing and maintaining technical 

requirements, reviewing technical products, and preparing and administering technical 

processes and policies for disciplines and systems under their purview. 

The warrant system provides a disciplined formal procedure that is standardized across the 

Agency, and a process that is recognized inside and outside NASA in the execution of 

Independent Technical Authority. 

On November 23, 2004, the NASA Administrator issued the policy and requirements to 

implement Independent Technical Authority through a technical warrant process. This policy 

was issued under NPD 1240.4 NASA Technical Authority (draft) and NPR 1240.1 Technical 

Warrant System (draft), and is in accordance with the 9.1-1 Plan. The Chief Engineer has 

selected Technical Warrant Holders for many critical areas, including all major systems for 

the Space Shuttle. These Technical Warrant Holders are making technical decisions necessary 

for safe and reliable operations and are involved in return to flight activities for the Space 

Shuttle. NASA is selecting additional Technical Warrant Holders to span the full range of 

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technical disciplines and systems needed across the Agency. The Chief Engineer issued 

several new warrants in March 2005, including one for Systems Safety Engineering which 

will help revitalize the conduct of safety analyses (failure mode and effects analysis – FMEA, 

hazards analysis, reliability engineering, etc.) as part of design and engineering. The Chief 

Engineer will continue to issue warrants as required. 

3.14.3.1.2 Technical Conscience 

Technical conscience is personal ownership of the technical product by the individual who is 

responsible for that product. Committee reviews, supervisory initials, etc., do not relieve these 

individuals of their obligation for a safe and reliable mission operation if their technical 

requirements are followed. Technical conscience is also the personal principle for individuals 

to raise concerns regarding situations that do not “sit right” with the Agency’s mandate for 

safe and reliable systems and operations. With adoption of the Independent Technical 

Authority and the warrant system, technical personnel have the means to address and 

adjudicate technical concerns according to the requirements of the situation. The Independent 

Technical Authority and Technical Warrant Holders provide the means for independent 

evaluation and adjudication of any concern raised in exercising technical conscience. 

3.14.3.2 Safety and Mission Assurance (R7.5-2) 

To address the authority issue raised by the accident board, NASA has strengthened the 

traditional policy oversight over NASA programs provided by the Office of Safety and 

Mission Assurance (OSMA) with explicit authority of the Administrator through the Deputy 

Administrator to enforce those policies. The Chief Safety and Mission Assurance Officer 

provides leadership, policy direction, functional oversight, assessment, and coordination for 

the safety, quality, and mission assurance disciplines across the Agency. Operational 

responsibility for meeting the requirements of these disciplines rests with the Agency’s 

program and line organizations as an integral part of the NASA mission. To increase OSMA’s 

“line authority” over field SMA activities, NASA has taken four important steps: 

1. The Chief Safety and Mission Assurance Officer now has explicit authority over 

the selection, relief, and performance evaluation of all Center SMA Directors as 

well as the lead SMA managers for major programs – including Space Shuttle 

and International Space Station – and the Director of the Independent 

Verification and Validation (IV&V) Center. 

2. The Chief Safety and Mission Assurance Officer will provide a formal 

“functional performance evaluation” for each Center Director to their 

Headquarters Center Executive each year. 

3. “Suspension” authority is delegated to the Center Directors and their SMA 

Directors. This authority applies to any program, project, or operation conducted 

at the Center or under that Center’s SMA oversight regardless of whether the 

Center also has programmatic responsibility for that activity. 

4. The Safety and Mission Assurance community, through their institutional chain 

of command up to the Deputy Administrator, now has authority to decide the 

level of SMA support for the project/program. 

NASA safety and mission assurance support for the Space Shuttle Program consists of 

dedicated program office staff, technical support from the centers, and functional oversight 

from the Headquarters OSMA. The program’s SMA Manager reports directly to the Space 

Shuttle Program Manager and is responsible for execution of the safety and quality assurance 

requirements within the program. The program SMA Office integrates the safety and quality 

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assurance activities performed by all Centers for various projects and program elements 

located at those Centers. 

The Center SMA Directorates provide technical support to the program’s SMA Manager. 

They also provide independent safety and quality assurance functions in the form of 

independent assessments, safety, and reliability panel reviews. Finally, they provide a cadre of 

personnel dedicated to the Headquarters OSMA Independent Assessment function. 

3.14.3.2.1 SMA Independence 

The CAIB recommendation requires that OSMA be independently funded. After the Report of 

the Presidential Commission on the Space Shuttle Challenger Accident, also known as the 

Rogers Commission Report, NASA created the Office of Safety, Reliability and Quality 

Assurance, later renamed OSMA, and specifically set up its reporting and funding to be 

separate from the Office of the Chief Engineer and any of the programs. At the time of the 

Columbia accident, all funding for OSMA was in the general and administrative (G&A) line, 

separate from all other program, institutional, and mission support and functional support 

office funding. All permanent OSMA personnel are dedicated to OSMA and, therefore, 

independent of program or other mission support and functional support offices. This plan 

retains independent reporting and funding approach consistent with the CAIB 

recommendation. 

With respect to center-based civil servants and their support contractors performing safety, 

reliability, and quality assurance tasks, this plan calls for significant change. The 9.1-1 Plan 

establishes that the institution, not the program, decides SMA resource levels. Under the 

oversight of Headquarters Center Executives, centers will set up “directed service pools” to 

allow SMA labor to be applied to programs and projects in the areas and at levels deemed 

necessary by SMA Directors and their institutional chain of authority. The SMA Directors 

will pre-coordinate the use of their resources with the programs to foster understanding of 

how SMA labor will be used. This approach will guarantee both organizational and funding 

independence from the programs in a way that fully addresses the CAIB findings. Finally, the 

Headquarters OSMA will, for the first time, be a voting member of the Institutional 

Committee wherein institutional (including the directed service pool) budget decisions are 

made for the Agency. 

The prior definition of independence focused on organizational independence, and the Space 

Shuttle program and project managers had approval authority for about 99 percent (based on 

FY03 estimates) of total SMA funding level for Space Shuttle (including all contractor and 

Center NASA and support contractor SMA resources). The remaining 1 percent consisted of 

Center SMA supervisor time (paid by center general and administrative funds) and 

approximately $2 million per year of Space Shuttle Independent Assessment activity paid for 

by Headquarters OSMA. 

Under the new definition of independence, which now includes the directed service pool, the 

Space Shuttle Program has funding approval authority for only about 70 percent of the total 

SMA funding level. This funding pays for Space Shuttle prime and subcontractor SMA and 

for the small civil service SMA Management Office in the program. Remaining funding 

approval is accomplished through the directed service pool, and is therefore independent from 

the program. 

3.14.3.2.2 SMA Capability 

To address SMA capability, all centers have reviewed their safety and mission assurance 

skills and resources for adequacy and added positions as required. Headquarters OSMA has 

increased significantly its ability to provide functional oversight of all NASA safety and 

mission assurance programs. Staffing has been increased in the Headquarters office from 48 

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to 51 people, partly to accommodate increased liaison needs created by the addition of NASA 

Engineering and Safety Center (NESC), IV&V, and new assurance programs. At the time of 

the Columbia accident, OSMA had a budget of $6 million per year for Independent 

Assessments, its primary assurance tool. OSMA will continue to send Independent 

Assessment funding to the centers for use by SMA Directorates in performing center audits 

and supporting OSMA audits and assessment of resident programs. 

The NASA Engineering and Safety Center (NESC), as a technical resource available to the 

SMA community, in coordination with the ITA, combined with IV&V and Independent 

Assessment capabilities, provides an unprecedented increase in the independent assessment, 

audit, and review capability. This will reinforce the SMA community’s role in providing 

verification and assurance of compliance with technical requirements owned by the 

Independent Technical Authority, and in technical support for mishap investigations. 

The Independent Technical Authority will own all technical requirements, including safety 

and reliability design and engineering standards and requirements. OSMA will continue to 

develop and improve generic safety, reliability, and quality process standards, including 

FMEA, risk, and hazards analysis processes; however, the Independent Technical Authority 

will specify and approve these analyses and their application in engineering technical 

products. 

NASA is also improving its trend analysis, problem tracking, and lessons learned systems 

(CAIB Finding F7.4-9, -10, and -11), in a concerted effort to ensure the Independent 

Technical Authority invokes appropriate technical requirements. In order to improve OSMA 

insight and reduce the confusion cited in F7.4-13, NASA is formalizing its Prelaunch 

Assessment Review (PAR) process for the Space Shuttle and International Space Station, and 

the equivalent processes for expendable launch vehicles and experimental aerospace vehicle 

flight approvals, called Independent Mission Assurance Reviews (IMAR). Both processes 

have been standardized into a new NASA-wide review process called Safety and Mission 

Assurance Readiness Reviews (SMARR). 

In addressing the CAIB concern about the lack of mainstreaming and visibility of the system 

safety discipline (F7.4-4), OSMA has taken two actions, one long term and the other 

completed. First, the audit plan includes the project and/or line engineering assessment of the 

OSMA system safety engineering per new NASA policy directives for program management 

and ITA. Secondly, for some years the senior system safety expert in the Agency was also the 

OSMA Requirements Division Chief (now Deputy Chief, OSMA). To respond to the CAIB 

concern, OSMA has brought on a full-time experienced system safety manager who is the 

Agency’s dedicated senior system safety assurance policy expert. In addition, the Chief 

Engineer will select a Systems Safety Engineering Technical Warrant Holder who will be 

responsible for establishing systems safety engineering requirements. 

The SMA Directorates supporting the Space Shuttle Program are staffed with a combination 

of civil service and support contractors providing system safety, reliability, and quality 

expertise and services. Their role is predominantly assurance in nature, providing the program 

with functional oversight of the compliance with requirements of the contractor engineering 

and operations. The civil service personnel assigned to work on Space Shuttle are functionally 

tied to their Center SMA organizations, and although some are collocated with their project or 

contractor element, their official supervisors are in the Center SMA organization. 

The System Safety Review Panel (SSRP) process continues to evolve as the relationship 

between the ITA, SMA, and the Space Shuttle Program is defined and understood. This plan 

redefines the SSRP as the Engineering Risk Review Panels (ERRP). The ERRP is designed to 

improve engagement by the engineering community into the safety process, including the 

development and maintenance of documentation such as hazard reports. 

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The organizational structure of the ERRP will consist of Level II (Program) and Level III 

(Project/Element) functionality. The ERRP structure and process continues to evolve in a 

phased approach. Until return to flight, the Space Shuttle System Technical Warrant Holder 

will be represented at all ERRP levels through trusted agents who are assigned to support each 

ERRP. The trusted agents ensure that the engineering interests of the Independent Technical 

Authority are represented at all working levels of the ERRP and are reflected in the products 

resulting from these panels. After return to flight, the Shuttle System Technical Warrant 

Holder will reassess his/her role in all Space Shuttle Program panels and boards that deal with 

flight safety issues, including the ERRP. 

The Level II Panel will ensure that the safety integration function remains at the Program 

level. It will have representation by all program elements as well as the Engineering 

Directorate, ITA, and SMA. The Lead ERRP Manager will also assure that Level III panels 

operate in accordance with safety program requirements. The Level II Panel exists to oversee 

and resolve integrated hazards, forwarding them to the System Integration Configuration 

Board (SICB), and finally to the ITA and the Space Shuttle Program Manager for approval. 

The Level III ERRPs will consist of a Johnson Space Center (JSC) Panel dealing with 

the Orbiter, extravehicular activity, government-furnished equipment, and integration 

responsibility; a Marshall Space Flight Center (MSFC) Panel that handles the External Tank, 

Solid Rocket Booster, Reusable Solid Rocket Motor, and Space Shuttle Main Engine; and a 

Kennedy Space Center (KSC) Panel that deals with ground servicing equipment and ground 

operations. As presently defined, the Level III Panels will be chaired by the independent SMA 

Directorates at each center, again with representation by trusted agents at these panels. 

The Space Operations Mission Directorate Space Shuttle Certificate of Flight Readiness 

(CoFR) process is being updated to clearly show the new SMA, Integration, and Independent 

Technical Authority roles and responsibilities. Part of that will be a requirement for 

concurrence by the Chief Safety and Mission Assurance Officer on the flight readiness 

statement as a constraint to mission approval. 

3.14.3.3 Integration of the New ITA and SMA (R7.5-1/R7.5-2) 

In a practical sense, the people that perform the responsibilities of SMA and the ITA need to 

be involved within a program or project beginning in the early stages and continuing for the 

life of the program or project. CAIB Recommendation 7.5-1 defined what activities at the 

program level must be clearly controlled by the Independent Technical Authority. At the same 

time, Chapter 7 of the CAIB report makes it clear that the SMA organization must be 

independent of the program and technically capable to provide proper check-and-balance with 

the program. Finally, the SMA organization must be able to perform its assurance functions in 

support of but independent of both program and engineering organizations. 

The Independent Technical Authority has delegated fully to responsible individuals who hold 

warrants for systems and engineering disciplines. Fundamentally, this concept brings a 

“balance of power” to program management such that the Independent Technical Authority 

sets technical requirements, the programs execute to that set of technical requirements, and 

the SMA organization assures the requirements are satisfied. This means that the Independent 

Technical Authority owns the technical requirements and will be the waiver-granting 

authority for them. 

The principal effect of the foregoing is the clear assignment of responsibility for execution of 

design and engineering, including the safety functions (FMEA, hazards analysis, reliability 

engineering, etc.) to engineering with the Independent Technical Authority setting 

requirements and approving the resulting engineering products. In this context, SMA 

organizations have the responsibility for independently assuring that delivered products 

comply with requirements. 

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3.14.3.4 Systems Engineering and Integration (R7.5-3) 

The CAIB found several deficiencies in the organizational approach to program-wide system 

engineering integration for the Space Shuttle Program. Their Recommendation 7.5-3 calls for 

a reorganization of the Space Shuttle Integration Office to “make it capable of integrating all 

elements of the Space Shuttle Program, including the Orbiter.” The CAIB concluded, 

“...deficiencies in communication ...were a foundation for the Columbia accident. These 

deficiencies are byproducts of a cumbersome, bureaucratic, and highly complex Shuttle 

Program structure and the absence of authority in two key program areas that are responsible 

for integrating information across all programs and elements in the Shuttle program.” 

3.14.3.4.1 Integration Definition 

NASA defines integration as a system engineering function that combines the technical 

efforts of multiple system elements, functions, and disciplines to perform a higher-level 

system function in a manner that does not compromise the integrity of either the system or the 

individual elements. The integration function assesses, defines, and verifies the required 

characteristics of the interactions that exist between multiple system elements, functions, and 

disciplines, as these interactions converge to perform a higher-level function. 

3.14.3.4.2 Restructured Space Shuttle Systems Engineering and Integration Office 

NASA has restructured its Shuttle Integration Office into a Space Shuttle Systems 

Engineering and Integration Office (SEIO) to include the systems engineering and integration 

of all elements of the Space Shuttle system. The SEIO Manager now reports directly to the 

Space Shuttle Program Manager, thereby placing the SEIO at a level in the Space Shuttle 

organization that establishes the authority and accountability for integration of all Space 

Shuttle elements. The new SEIO charter clearly establishes that it is responsible for the 

systems engineering and integration of all Space Shuttle elements. The number of civil 

service personnel performing analytical and element systems engineering and integration in 

the SEIO was doubled by acquiring new personnel from the JSC Engineering and Mission 

Operations Directorates and from outside of NASA. The role of the System Integration Plan 

(SIP) and the Master Verification Plans (MVP) for all design changes with multi-element 

impact has been revitalized. The SEIO is now responsible for all SIPs and MVPs, including 

those developed for all major changes that impact multiple Space Shuttle elements. 

3.14.3.4.3 Orbiter Project Office 

The Space Shuttle Vehicle Engineering Office is now the Orbiter Project Office, and its 

charter is amended to clarify that SEIO is now responsible for integrating all flight elements. 

NASA reorganized and revitalized the Integration Control Board, with the Orbiter Project 

Office now a mandatory member. The Space Shuttle Flight Software organization was moved 

from the Orbiter Project into the SEIO. This reflects the fact that the Shuttle Flight Software 

Office manages multiple flight element software sources besides the Orbiter. 

3.14.3.4.4 Integration of Engineering at Centers 

All Space Shuttle Program integration functions at JSC, KSC, and MSFC are now 

coordinated through, and receive technical direction from, the SEIO. The former MSFC 

Propulsion Systems Integration office is now called the Propulsion Systems Engineering and 

Integration (PSE&I) office. Agreements between the PSE&I Project Office and the 

appropriate MSFC engineering organizations are being expanded to enhance anomaly 

resolution within the Space Shuttle Program. 

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3.14.3.4.5 Integrated Debris Environments/Certification 

The SEIO is also responsible for generation of all natural and induced design environments 

analyses. Debris is now treated as an integrated induced environment that will result in 

element design requirements for generation limits and impact tolerance. All flight elements 

are being reevaluated as potential debris generators. Computations of debris trajectories under 

a wide variety of conditions define the induced environment due to debris. The risk associated 

with the Orbiter Thermal Protection System will be reassessed for this debris environment, as 

will the systems of all flight elements. 

3.14.3.5 Summary 

The reorganized SEIO now addresses all elements of the Space Shuttle system including the 

Orbiter. The SEIO manager located at JSC has oversight and control of matrix Systems 

Engineering and Integration support from KSC and MSFC. SEIO works in compliance with 

Independent Technical Authority requirements and the SMA organization. SEIO recognizes 

the Independent Technical Authority as the approval authority for variances to technical 

requirements, as documented in NSTS 07700, Volume IV. Additionally, SEIO will conduct 

integrated hazard analyses with the oversight of the Space Shuttle System Technical Warrant 

Holder. The results of these analyses will be accepted or rejected by the Space Shuttle System 

Technical Warrant Holder prior to use. 

3.14.4 RTF TG Assessment 

In support of our assessment of CAIB Recommendation 9.1-1, the RTF TG conducted factfinding with several former CAIB members, representatives of the NASA-Navy 

Benchmarking Team, and various senior NASA officials on numerous occasions during the 

last two years. 

CAIB required only a plan to implement the 7.5-series of recommendations before return to 

flight. The accident board, as did many of the Task Group, assumed that the return-to-flight 

would not be a two-plus-year endeavor and a plan was all that could be reasonably expected 

before the launch of STS-114. Thus, strictly speaking, NASA has largely complied with this 

recommendation. 

With the passage of time, however, the NASA Administrator announced his desire to have the 

elements of R9.1.1 implemented, at least for the Space Shuttle Program, before the return to 

flight. The Task Group has therefore been able to monitor the implementation of at least some 

of the plan, gauge early effects, and evaluate whether the individual elements of the 7.5-series 

of recommendations meet the intent of the CAIB. On that basis, the results are mixed. 

3.14.4.1 Recommendation 7.5-1: Independent Technical Authority 

The CAIB was concerned with the conflict of interest inherent in the Space Shuttle Program 

Manager balancing resources, schedule, and safety. In that role, prior to the Columbia 

accident, the program manager was often called upon to approve waivers of technical 

requirements – waivers that could compromise program safety – sometimes in order to meet 

schedule or budget constraints. 

The road to the current plan was neither straight nor smooth – there was a great deal of 

resistance from the safety community within NASA as well as from the various NASA 

centers. Some in the safety community view the current construct as a diminution of 

authority, with certain standards and waiver authority transferred to the ITA. The original 

assignment of NESC to SMA and its subsequent movement to the Chief Engineer was also 

viewed as a further relegation of authority. The NASA centers, maintaining their historical 

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position, argued that the accident board’s recommendation for Headquarters-level ITA was 

misguided – that centers are better able to manage technical authority. 

The Agency’s plan for implementing a new agency-wide Independent Technical Authority 

places waiver-approval in the hands of the Chief Engineer, who is independent of all 

programs. However, because of internal dissension, the final organizational structure of the 

Independent Technical Authority was only recently determined and full implementation has 

not yet been accomplished. The establishment of roles and responsibilities, in addition to 

technical waivers, is being determined in conjunction with the Office of Safety and Mission 

Assurance and the Systems Engineering and Integration Office. 

The Chief Engineer has chosen to exercise this authority through delegation to a series of 

Technical Warrant Holders. Each warrant holder is considered to be among the foremost 

technical experts in his or her field employed by NASA. Warrant holders essentially own the 

technical standards specified in their warrant and possess the discretion to change the 

standards and grant waivers to them. 

This construct is fully consistent with the intent of the CAIB. However, not all details of 

implementation have been worked out, especially the roles and responsibilities of the 

Independent Technical Authority relative to Office of Safety and Mission Assurance and the 

Systems Engineering and Integration Office. Further, while a number of warrant holders have 

been designated, not all will be in place before the return to flight. 

There also remains resistance within NASA to the totality of the change implied by the 

Independent Technical Authority concept. Nevertheless, the Agency’s implementation of this 

recommendation is viewed by many in Congress and the public as an indicator of the 

Agency’s willingness to change. Further implementation of the Independent Technical 

Authority and its durability will be of continued interest long after the return to flight. 

Ultimately, the sustainability of the Independent Technical Authority will be one measure of 

NASA’s willingness to change critical processes. 

3.14.4.2 Recommendation 7.5-2: Safety and Mission Assurance 

The CAIB viewed the organization of the Agency’s Space Shuttle safety offices as a 

contributing factor to NASA not being appropriately attuned to minimizing risks. They 

recommended: “NASA Headquarters Office of Safety and Mission Assurance should have 

direct line authority over the entire Space Shuttle Program safety organization and should be 

independently resourced.” 

After review, NASA determined it is preferable to keep the Center Directors in the line of 

authority so they retain some responsibility for safety. Therefore, NASA has chosen not to 

completely comply with the CAIB recommendation. Instead, they have increased the 

authority of Headquarters, but are keeping the director of each NASA Center responsible for 

safety and mission assurance by continuing to have each center’s SMA organizations report to 

the Center Director rather than the Chief Safety and Mission Assurance Officer at 

Headquarters. As part of these changes, NASA has strengthened the role Headquarters plays 

in employment and evaluation of safety personnel, and removed decisions for funding safety 

activities from the Space Shuttle Program. 

The Task Group has also noted OSMA efforts to enhance its auditing role – making sure that 

safety-related processes are adequate and implemented. Expanded auditing can help ensure 

that the remaining center-centric aspect of managing the safety organizations is not 

detrimental to the overall agency adoption of adequate safety systems. Like R7.5-1, the 

success of the implementation of this recommendation will require consistent attention by 

NASA leadership to ensure survival. 

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3.14.4.3 Recommendation 7.5-3: Systems Engineering and Integration 

The CAIB noted the apparent inability of the Space Shuttle Program to integrate across its 

various components. In the long history of NASA, integration has been the hallmark of both 

the challenges and successes of the Agency. In the particular case of the Columbia accident, 

foam from the External Tank inflicted catastrophic damage to the Orbiter. Previous instances 

of foam debris – including one just two flights prior to STS-107 – had not been taken 

sufficiently seriously by the managers of either the External Tank Project or the Orbiter 

Project. It appeared that no one was in charge of monitoring trends between and among 

flights, and data was generally unable to be shared between NASA Centers and program 

elements. The Agency’s capabilities for system engineering had atrophied. 

In response to the CAIB recommendation, NASA enhanced the reach and responsibilities of 

the SEIO operation within the Space Shuttle Program. Additional resources and personnel 

were added and new processes instituted. The integration function was improved and 

coordination between the program elements is more common. In addition, system analysis has 

improved; e.g., analytical modeling of debris flow. In strengthening system analysis and 

integration, the basic intent of R7.5-3 has been partially accomplished. 

However, weaknesses remain in the system engineering function and related processes. In 

many cases unverified and unvalidated analytical modeling is replacing sound engineering 

rationale as the hallmark of establishing engineering standards, measuring the attainment of 

technical requirements, and assessing risk. 

The Task Group and other outside observers (e.g., The Aerospace Corp. audit and NESC) 

have faulted NASA for inadequate documentation. Requirements have often been established 

long after design, testing, or hardware modifications have taken place; e.g., foam debris 

allowables, or repair material to be flown on the next flight manufactured prior to the 

completion of the establishment of requirements or formal design reviews. In some cases, 

such as ice debris from the External Tank, or software to control the bellows heaters, the 

requirements have yet to be established, as of the June 8, 2005 Task Group’s public meeting. 

Further, the SEIO management of the Design Certification Review/Design Verification 

Review (DCR/DVR) process for the return to flight has been inconsistent – each project has 

executed these critical processes in different manners, ranging from rigorous reviews to status 

reports. In many cases, minutes of the meetings were not published and required actions were 

not tracked. Information is therefore not systematically collected and may be lost or not easily 

accessible; e.g., the list of actions from the first Program DCR, conducted April 19, 2005, 

took over three weeks to assemble and consisted of different, non-collated lists contained in 

over half a dozen non-standardized files. 

3.14.4.4 Conclusion 

NASA has a mature plan to restructure the organization in response to the CAIB 

recommendation and therefore satisfies the letter of R9.1-1. Planned implementation of the 

Independent Technical Authority comports with CAIB intent – it will take some time to see if 

the process is robust enough to be sustainable. The planned response to R7.5-2 is intentionally 

not consistent with CAIB intent – NASA simply disagrees that the best organization for SMA 

is direct reporting to Headquarters. Implementation of R7.5-3 is uneven, with improved 

integration and system analysis but remaining gaps in system engineering capability. 

The RTF TG assessment of NASA’s actions was completed at the June 8, 2005 meeting. The 

intent of CAIB Recommendation 9.1-1 has been met. 

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3.14.5 RTF TG Observations 

The Task Group observes that the R9.1-1 plan is a first iteration, and the implementations of 

the 7.5-x recommendations are works in progress. Constant senior leadership vigilance of the 

implementation will be required to ensure maturity and resolve potential areas of conflict or 

confusion in terms of roles and responsibilities. The Task Group suggests that the Aerospace 

Safety Advisory Panel (ASAP) continue to review the ongoing implementation of the 7.5-x 

recommendations. 

Because of a lengthy NASA internal debate over the implementation of Recommendation 

R7.5-1, planning was not finalized until November 2004, resulting in a major organizational 

change to the program late in 2004. This resulted in confusion over roles and responsibilities 

and significant changes to program documentation immediately prior to the then-scheduled 

return-to-flight launch of STS-114. Of particular importance for NASA leadership is to ensure 

that the Independent Technical Authority implementation fulfills one of its stated key 

principles, specifically, “clear and unambiguous ... authority, responsibility, and 

accountability.” 

Although not directly related to any CAIB recommendation, the Task Group applauds 

NASA’s establishment of the NASA Engineering and Safety Center (NESC) and observed 

valuable work produced by NESC. Over time, NASA leadership needs to ensure clarity of the 

NESC role (and more importantly, the NESC authority) in decision making. 

With respect to Recommendation R7.5-2, given the NASA alternative to “direct line 

reporting” and the history from Challenger to Columbia, the Task Group feels that significant 

NASA Headquarters leadership attention will be required to ensure SMA “independence” and 

appropriate authority. Enhancing Headquarters auditing capabilities and performance are 

critical to ensure this result. NASA Headquarters may wish to develop specific metrics and 

oversight to periodically ensure the independence and authority of critical SMA functions, 

including their performance in the Mission Management Team. 

Since the Space Shuttle SMA Manager is the voting member of the MMT, constant vigilance 

will need to be maintained to ensure the independence of the safety function and that close 

communications are maintained with those SMA directors which possess “suspension 

authority.” 

In regards to recommendation R7.5-3, the Task Group expects that NASA will address the 

remaining identified weaknesses in the systems engineering function and processes; will 

demand rigorous documentation that sustains effective systems integration and engineering; 

and will require improvements in standards for (and standardization of) validation, 

verification, and certification requirements for the development and use of analytical models. 

NASA further needs to assess the impact of its contractual relationships on effective systems 

engineering and integration. The Task Group was advised very shortly after its formation by 

Shuttle management that the Space Flight Operations Contract (SFOC) needed revitalization 

to ensure effective SEIO functions and/or those workforce capabilities reestablished in-house. 

The SSP needs to ensure that flight-to-flight verification and evolution of SEI databases are 

continuously updated, documented and appropriately provided for future flight and MMT 

decision making. 

The Task Group also observes that a significant workforce challenge is facing NASA. The 

Space Shuttle Program long ago transitioned, largely, to an “operations and maintenance” 

organization, losing the skill set and talents required to do the developmental work that was 

required post-Columbia. The Space Shuttle will remain a “developmental” vehicle until its 

retirement, and will require a developmental mindset, skill set, and discipline at both the 

workforce and management levels. 

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3.15 CAIB Recommendation 10.3-1 – 

Digitize Closeout Photos 

Develop an interim program of closeout photographs for all critical sub-systems that differ 

from engineering drawing. Digitize the closeout photograph system so that images are 

immediately available for on-orbit troubleshooting. 

3.15.1 RTF TG Interpretation 

During the investigation, the Columbia Accident Investigation Board (CAIB) encountered 

numerous engineering drawings that were inaccurate. Further, they discovered a large number 

of engineering change orders had not been incorporated into the drawings. Tied in with this, 

CAIB investigators were not able to access needed closeout photography for several weeks. 

3.15.2 Background 

Closeout photographs have been archived in a database at the Kennedy Space Center since the 

beginning of the program. (Closeout photos are pictures taken of Space Shuttle areas before 

they are sealed for flight.) This database was primarily used by the KSC engineering 

community and photos were filed based on the work authorization document that originally 

requested the photograph, making it difficult to search for particular images. A large number 

of non-standardized cameras were used resulting in arbitrary resolution of critical images. In 

addition, there were no clear requirements to photograph all critical closeout activities, or to 

record changes to the vehicle configuration. 

In the years since the Space Shuttle was designed, NASA has not updated many of its 

engineering drawings or converted to computer-aided drafting systems. The accident board’s 

review of those engineering drawings revealed numerous inaccuracies; in particular, the 

drawings do not incorporate many engineering changes made in the last two decades. Equally 

troubling was the difficulty in obtaining the drawings, accurate or not: some took up to four 

weeks to receive. Although some close-out photography was available as a substitute, these 

images took up to six weeks to obtain. The Aerospace Safety Advisory Panel noted similar 

difficulties in its 2001 and 2002 reports. 

3.15.3 NASA Implementation 

The Space Shuttle Program formed a Photo Closeout Team consisting of members from the 

engineering, quality, and technical communities to identify and implement necessary 

upgrades to the processes and equipment involved in vehicle closeout photography. Kennedy 

Space Center (KSC) closeout photography includes the Orbiter, External Tank, Solid Rocket 

Boosters, and Space Shuttle Main Engines, based on project requirements. The Photo 

Closeout Team divided the CAIB recommendation into two main elements: (1) increasing the 

quantity and quality of closeout photographs, and (2) improving the retrieval process through 

a user-friendly web-based graphical interface system. 

Led by the Photo Closeout Team, the Space Shuttle Program completed an extensive review 

of existing closeout photo requirements. This team systematically identified the deficiencies 

of the current system and assembled and prioritized improvements for all elements. These 

priorities were distilled into a set of revised requirements that has been incorporated into 

program documentation. NASA also added a formal photography step for KSC-generated 

documentation and mandated that photography of all Material Review Board (MRB) reports 

be archived in the Shuttle Image Management System (SIMS) database. These MRB problem 

reports provide formal documentation of known subsystem and component discrepancies, 

such as differences from engineering drawings. 

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The Nikon D100 

digital camera 

provides a resolution 

of 6.1 megapixels. 

The Shuttle Image 

Management System 

(SIMS) database 

features a graphical 

interface. 

To meet the new requirements and ensure a comprehensive and accurate database of photos, 

the Kennedy Space Center established a baseline for photographic equipment and quality 

standards, initiated a training and certification program to ensure all operators understand and 

can meet these requirements, and improved the SIMS. To verify the quality of photographs 

taken and archived, NASA has developed an ongoing process that calls for SIMS 

administrators to continually audit the photos being submitted for archiving in the SIMS. 

Photographers who fail to meet the photo requirements will lose their certification pending 

further training. Additionally, to ensure the robustness of the archive, poor-quality photos will 

not be archived. 

NASA determined the minimum resolution for 

closeout photography should be 6.1 megapixels to 

provide the necessary clarity and detail. KSC has 

procured 36 Nikon D100 6.1 megapixel cameras 

and completed a test program in cooperation with 

Nikon to ensure the cameras meet the Agency’s 

requirements. 

To improve the accessibility of the SIMS database, 

NASA developed a web-based graphical interface. 

Users can easily view the desired Space Shuttle 

elements and systems and quickly drill down to 

specific components, as well as select photos from 

specific Orbiters and missions. SIMS also includes 

hardware reference drawings to help users identify 

hardware locations by zones. These enhancements will enable Mission Evaluation Room and 

Mission Management Team personnel to quickly and intuitively access relevant photos 

without lengthy searches, improving their ability to respond to contingencies. 

NASA has revised the Operation and Maintenance Requirements System to mandate that 

general closeout photography be performed at the time of normal closeout inspection process 

and that digital photographs be archived in SIMS. Overlapping photographs will be taken to 

capture large areas. NSTS 07700, Volume IV and the KSC MRB Operating Procedure have 

also been updated to mandate photography of visible MRB conditions be entered into the 

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SIMS closeout photography database. This requirement ensures all known critical subsystem 

configurations that differ from Engineering Drawings are documented and available in SIMS 

to aid in engineering evaluation and on-orbit troubleshooting. 

Training for critical personnel is complete, and will be ongoing to ensure the broadest 

possible dissemination within the user community. Photographer training is complete and 

associated classes are taught on a regular basis. SIMS computer-based training has been 

developed and released. Use of SIMS has been successfully demonstrated in a launch 

countdown simulation at KSC, which included participation from the KSC Launch Team, JSC 

Flight Control Team, Mission Evaluation Room, MSFC Huntsville Operations and Support 

Center, and the Systems Engineering and Integration Office. 

3.15.4 RTF TG Assessment 

The Task Group conducted numerous fact-finding activities during 2004 concerning closeout 

photography and the SIMS database. These efforts complemented earlier meetings with KSC 

staff and their contractors to review their response to the CAIB recommendation in December 

2003. New standardized 6.1 megapixel cameras have been acquired and are now being used 

in closeout and configuration photography. Generic and return to flight-specific closeout 

photo requirements have been established by program elements and documented. 

Photography of areas already closed has been deemed adequate. NASA identified 

enhancements to the SIMS and the necessary upgrades are complete. Updated training 

material has been developed for users of the SIMS database and users have received training 

at the Kennedy Space Center, Johnson Space Center, and Marshall Space Flight Center from 

local trainers. Through several integrated launch countdown simulations, the Space Shuttle 

Program staff has confirmed that the modifications to the SIMS database satisfy their needs. 

When the accident board wrote their recommendations, they assumed that the Space Shuttle 

Program would continue for the long term, and indicated digital photography could provide 

an interim solution pending the digitizing and updating of all Space Shuttle engineering 

drawings (R10.3-2). However, based on the National Policy decision to retire the Space 

Shuttle no later than 2010, the Task Group concurs with the NASA decision that it does not 

make economic sense to expend the resources to make major changes to the drawings. The 

digital closeout photography provides an adequate solution until the end of the program. 

Each Space Shuttle 

element is 

represented in the 

SIMS database. 

Page 109 of 216 
Final Report of the Return to Flight Task Group 

Actual photographs 

from the SIMS 

database of 

STS-114. On the left, 

a photo of the liquid 

oxygen feedline 

where it comes out 

of the External Tank; 

on the right, a shot of 

the inside of a piece 

of the reinforced 

carbon-carbon wing 

leading edge panel. 

More photographs 

from SIMS. At left is 

a turbopump impeller 

on a Space Shuttle 

Main Engine; at right, 

the bolts around a 

field joint of a Solid 

Rocket Booster. 

More from the SIMS 

database. At left, the 

forward OrbiterExternal Tank attach 

point; at right, the left 

main landing gear of 

Discovery. 

However, if the Space Shuttle Program is extended past 2010, or if a Shuttle-Derived Launch 

Vehicle (SDLV) is selected as a future booster, this decision should be reevaluated. 

The RTF TG initial assessment of NASA’s actions was completed at the July 22, 2004, 

teleconference plenary where the assessment was conditionally closed. After receiving 

additional information from NASA, the assessment was fully closed at the December 16, 

2004, meeting. The intent of CAIB Recommendation 10.3-1 has been met. 

3.15.5 RTF TG Observation 

If the Space Shuttle Program is extended past 2010, or a Shuttle-Derived Launch Vehicle 

(SDLV) is selected as a future booster, the decision concerning updating the Space Shuttle 

engineering drawings should be reevaluated. 

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Final Report of the Return to Flight Task Group 

3.16 Raising the Bar Action SSP-3 – 

Contingency Shuttle Crew Support 

NASA Implementation Plan: NASA will evaluate the feasibility of providing contingency life 

support on board the International Space Station (ISS) to stranded Shuttle crew members 

until repair or rescue can be accomplished. 

3.16.1 RTF TG Interpretation 

Space Shuttle Program Action 3 (SSP-3) addresses Contingency Shuttle Crew Support 

(CSCS), the capability to harbor Space Shuttle crewmembers aboard the International Space 

Station (ISS) until a damaged Orbiter can be repaired or the crew rescued. The Columbia 

Accident Investigation Board (CAIB) did not make a specific recommendation with regard to 

CSCS, but Section 9.1 of the CAIB report listed the exploration of “all options for survival, 

such as provisions for...safe havens” as one of several necessary measures for safe flight. 

Section 6.4 of the CAIB report also assesses the possibility of rescuing a crew by launching 

another Space Shuttle. 

3.16.2 Background 

In the aftermath of the Columbia accident, NASA responded with a set of corrective actions 

characterized as “raising the bar” – not required by the CAIB for returning to flight, but selfimposed by the Space Shuttle Program. These actions are documented in the NASA 

Implementation Plan. One of these actions resulted in NASA examining options for providing 

a capability to sustain a Space Shuttle crew on the ISS should the Orbiter become unfit for 

entry. NASA chose to pursue CSCS as a functional emergency capability that is not certified, 

similar to how NASA addresses other emergency plans. Thus CSCS is not intended to 

mitigate known but unacceptable risks; rather, it is a contingency plan of last resort with 

limited capability to sustain the crew on the ISS. Finally, NASA committed to ensuring that a 

rescue Space Shuttle will be available for at least its next two flights. In fact, NASA 

leadership committed to the delay launch of STS-114 and STS-121, if necessary, until a 

rescue vehicle can be ready within the projected CSCS window. 

The Task Group chose to assess SSP-3 because NASA uses the CSCS capability as part of its 

launch rationale, and because NASA considers the ability to launch a rescue vehicle within 

estimated CSCS duration to be a constraint to launch for the first two return-to-flight 

missions. The CSCS capability bears on the safety and operational readiness of STS-114 and 

therefore falls within the purview of the Task Group to evaluate. 

3.16.3 NASA Implementation 

On June 9, 2004, the Space Flight Leadership Council approved pursuing the CSCS concept 

as an emergency capability for the first two return-to-flight missions, STS-114 and STS-121. 

NASA will revisit the feasibility and need for continued CSCS capability following STS-121. 

The CSCS capability will not be fault tolerant, and imposes no additional requirements for 

fault tolerance other than those that already exist. The capability is built on the presumption 

that, if necessary, all ISS consumables and Orbiter reserves will be depleted to support the 

combined crews aboard the ISS until a rescue mission can be launched. In the most extreme 

CSCS scenarios, it is possible that the ISS crew will need to return to Earth following the 

rescue of the Space Shuttle crew until consumables margins can be reestablished and a 

favorable safety review is completed. 

For the first two flights, NASA will ensure the capability to launch a rescue mission is 

available within the time period the International Space Station can reasonably sustain the 

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Final Report of the Return to Flight Task Group 

The International 

Space Station (ISS) 

could provide a safe 

haven for the crew of 

a damaged Orbiter 

using the 

Contingency Shuttle 

Crew Support 

capability described 

in SSP-3. 

combined crews of the ISS and the stricken Orbiter. This includes allowing sufficient time to 

evacuate the ISS following departure of the rescue Space Shuttle, if necessary. This time 

period, referred to as the International Space Station engineering estimate of supportable 

CSCS duration, represents a point between worst- and best-case scenarios based on 

operational experience and engineering judgment. The ISS Program will provide this estimate 

in advance of the first two return-to-flight missions as a part of the flight preparation process. 

To arrive at the engineering estimate, the ISS Program analyzed the impacts of maintaining 

seven additional people on the ISS in the event of CSCS. Their analyses indicate that at 

current operating levels, and with conservative assumptions of system viability, the combined 

crews can be supported long enough to allow the launch of a rescue mission. As consumables 

aboard the International Space Station are used by the normal crew prior to the launch of 

STS-114, the CSCS engineering estimate will change. The engineering estimate will be 

updated at specific milestones during the STS-114 mission planning process. 

As part of the CSCS concept, NASA will have a second Space Shuttle, designated STS-300 

for STS-114 and STS-301 for STS-121, ready for launch on short notice. The Space Flight 

Leadership Council has directed the ability to launch a rescue mission within the ISS Program 

engineering estimate will be a constraint to launch for the first two missions. 

Should a rescue mission become necessary, it would be subject to the same requirements as 

any other Space Shuttle mission, but processed on an accelerated schedule. The rescue Orbiter 

would be reconfigured with additional accommodations, including seating, for the crew of the 

stricken Orbiter. 

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The rescue Orbiter, Atlantis for STS-300 and Discovery for STS-301, would be crewed by 

four astronauts. Following launch, the rescue Orbiter would dock with the ISS using standard 

rendezvous and approach procedures. Any extra consumables would be transferred to the ISS. 

The stranded Orbiter crew would board the rescue Orbiter and return to Earth with the four 

rescue astronauts. If evacuation of ISS becomes necessary, the ISS crew would return to Earth 

via the Soyuz spacecraft docked at the ISS. 

Since, as currently configured, the ISS can only dock one Orbiter at a time, the stricken 

Orbiter must be undocked prior to arrival of the rescue Orbiter. NASA has developed 

procedures for undocking an unmanned Orbiter from the station, separating to a safe distance, 

then conducting a deorbit burn that will cause the Orbiter to enter and burn-up over an 

uninhabited oceanic area. These procedures have been developed in detail through the ISS 

Safe Haven Joint Operations Panel, and have been simulated in a joint integrated simulation 

involving flight controllers and flight crews from both the International Space Station 

Program and the Space Shuttle Program. 

The decision to implement CSCS would result in extremely serious consequences, including: 

exposure of the stricken Orbiter crew to a severe survival situation presenting the distinct 

possibility of loss of life; exposure of the rescue Orbiter crew to flying a vehicle possibly 

vulnerable to the same failure(s) that stranded the first Orbiter; the loss of an irreplaceable 

National asset (the stricken Orbiter); possible depletion of ISS resources to a level requiring 

evacuation of ISS; and the likely termination of all future Space Shuttle missions, 

significantly restricting the United State’s human access to space and utilization of the 

International Space Station. 

Given these extreme consequences of implementing CSCS, the Space Flight Leadership 

Council has made it clear that the Mission Management Team (MMT) will be responsible for 

orchestrating a recommendation to implement CSCS only upon clear evidence of catastrophic 

Thermal Protection System damage that cannot be satisfactorily repaired. Such a 

recommendation would be accompanied by an assessment of the risk of repeating the 

failure(s) that damaged the first Orbiter. This would be aided by the enhancements to the 

ascent and on-orbit imagery collection and analysis made since the Columbia accident. The 

MMT would make its recommendation through the Deputy Associate Administrator for 

International Space Station and Space Shuttle Programs to the Associate Administrator for 

Space Operations. The final risk-versus-risk trade and decision to implement CSCS, or not, 

would be made at the Agency level with appropriate notification to National Authorities. 

3.16.4 RTF TG Assessment 

Since the CSCS capability was not a CAIB recommendation, the Task Group had no 

predefined criteria to evaluate the capability against. Instead, the RTF TG established five 

conditions that it believed constituted an adequate CSCS contingency capability: 

1. Clear articulation of the role CSCS plays in NASA’s risk management 

framework for damage to the Orbiter Thermal Protection System from debris. 

2. Development of a dynamic, rigorous analytic process for estimating the number 

of days the ISS could sustain the seven crew stranded by a damaged Orbiter in 

addition to its two crewmembers. 

3. Development and demonstration of a robust plan for launching a rescue Orbiter, 

including safely undocking and de-orbiting a damaged Space Shuttle. 

4. Integration of CSCS plans and estimates into the pre-launch decision process 

and relevant documents. 

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Final Report of the Return to Flight Task Group 

5. Integration of the CSCS capability into the Mission Management Team (MMT) 

decision-making process, including a demonstration of its ability to consider the 

risk-versus-risk trades inherent in invoking CSCS, to make informed decisions 

in the face of these risks, and to implement CSCS procedures. 

This assessment is based on information that emerged from various fact-finding activities. 

Most prominent among these were a series of meetings between the RTF TG Operations 

Panel and NASA representatives, beginning on July 8, 2004. The objective of this meeting 

was to help the Operations Panel obtain a high-level understanding of the NASA Thermal 

Protection System risk reduction framework, the role of CSCS in that framework, and the 

extent to which NASA intended to develop the CSCS capability. The second meeting took 

place on August 10, 2004, to help understand the analytic approach by which NASA will 

estimate possible CSCS duration. Of particular concern was the health, stability, and 

resilience of the ISS habitat under the stress of nine people. 

In March, 2005, the Task Group observed the performance of the MMT during a simulation 

(sim #12), the objectives of which included analysis of tile damage and decision-making with 

regard to repair and the possibility of CSCS. Subsequently, a third fact-finding meeting 

occurred on March 22, 2005, to discern the extent to which the MMT had exercised the CSCS 

decision process. The fourth fact-finding meeting was on April 7, 2005, primarily to ascertain 

the NASA simulation supervisors’ assessment of the MMT ability to make decisions 

regarding CSCS, as demonstrated in various simulations. The fifth meeting took place on 

April 8 where the NASA simulation supervisors reviewed the training strategy for an 

additional MMT simulation (sim #13) targeted at the MMT decision-making process 

regarding repair, entry, and CSCS. Finally, on May 4, 2005, the Task Group observed the 

simulation in which the MMT was confronted with the choice between entry on an uncertified 

tile repair or the declaration of CSCS. 

The outcomes of these meetings, coupled with additional discussions, review of 

documentation, and the responses NASA provided to thirteen requests for information, form 

the basis for the Task group’s assessment of SSP-3. Overall, the RTF TG finds that NASA set 

a Raising the Bar action for themselves and exceeded it by a significant margin. The Task 

Group commends NASA for its excellent work on SSP-3. This conclusion is derived from the 

following assessments against the five conditions specified above for successful SSP-3 

implementation. 

3.16.4.1 Condition 1: Risk Reduction 

The NASA return-to-flight approach is founded on a framework for TPS risk reduction that 

has five hierarchically interrelated components: elimination of critical debris, impact detection 

during ascent, on-orbit damage detection, TPS repair, and crew rescue.1

 The Agency’s core 

risk management strategy has been to eliminate critical debris sources. Despite these efforts, 

there remains some probability that debris could cause catastrophic damage, although NASA 

expects to be able to generate an accepted risk rationale. To reduce this residual risk enough 

to accept it and provide adequate flight rationale, NASA intends to rely on a set of strategies 

and capabilities first to detect damage to the Orbiter through sensing, imaging, and on-orbit 

inspection, and then to either effect repair or rescue the crew with another Space Shuttle. 

Each of these capabilities faces technical challenges that create uncertainty about its viability 

and utility. Crew rescue also involves uncertainties associated with providing life support for 

the Space Shuttle and Space Station crews aboard ISS, undocking and de-orbiting the 

damaged Orbiter, and the launch of a rescue vehicle into a risk environment where damage, 

This approach is documented in The Integrated Risk Acceptance Approach for Return to Flight, May 

2005. 

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Final Report of the Return to Flight Task Group 

potentially from unknown or not-well-understood causes, has already occurred. Furthermore, 

CSCS itself exposes the crews aboard the ISS to the risks inherent in operating in a survival 

mode. Finally, CSCS may deplete ISS consumables and systems to the point that the ISS must 

be evacuated. In sum, a decision to invoke CSCS poses a severe threat to the future of the 

Space Shuttle Program and the International Space Station Program. 

These concerns prompted the RTF TG to query NASA about assessments of these 

uncertainties and risks, and of other unintended consequences that may result from CSCS. 

NASA reports that the Space Flight Leadership Council (SFLC) has discussed these risks and 

consequences “at various forums,” although they did not provide documentation of those 

discussions. They admitted that “no formal preflight assessment has been performed,” and 

intend to make a real-time assessment of the risk of rescue versus the risk of repair versus the 

risk of entry, should TPS damage occur. It is the sense of the RTF TG that while NASA 

recognizes these risks and the magnitude of potential consequences, they have not 

systematically developed a mature appreciation of this trade space. 

Nonetheless, it is conceivable the aggregate benefits of these capabilities to crew survival will 

outweigh these risks, therefore providing sufficient justification for NASA to accept the 

residual risk of damage to TPS that remains after mitigation of critical debris. NASA has 

appropriately developed CSCS as a viable but limited contingency capability to be invoked 

only under particular circumstances of extreme emergency. These circumstances are confined 

to Orbiter TPS anomalies only (and not to other system failures), and further to cases where 

Orbiter TPS has suffered damage that cannot be repaired adequately to permit safe entry, and 

therefore the lives of the Space Shuttle crew are in jeopardy. In other words, CSCS is a last 

resort in the event of a catastrophic damage scenario. Since most of the mitigation for risk 

associated with critical debris is based on the efforts to reduce the foam shedding of the 

External Tank, the major burden of risk mitigation is not required of the CSCS capability. 

Thus, NASA has chosen not to make CSCS a “certified” contingency. This is a choice that the 

RTF TG endorses, since it would require extreme efforts to balance logistic resources and 

manage ground-breaking international agreements – efforts disproportionate given the 

probability of a CSCS declaration. The CSCS capability is, nonetheless, an integral 

component of NASA’s TPS risk management strategy that, in conjunction with other 

capabilities, can help NASA accept the residual risk that remains despite efforts to mitigate all 

sources of critical debris. To be a viable component of overall risk reduction, though, CSCS 

must be a capability that can be reasonably executed in a survival mode, therefore a vigorous 

analysis is required to determine ISS duration estimates that exceed the time necessary to 

launch a rescue mission. 

3.16.4.2 Condition 2: Engineering Analysis 

The centerpiece of CSCS is an engineering analysis that supports ISS habitability for nine 

people for a predicted duration; therefore this analysis must thoroughly address issues such as 

consumables, ISS Environmental Control and Life Support System (ECLSS) functionality, 

systemic ISS biosphere stability, stowage, crew protocols for food and exercise, and impacts 

from changes to launch schedules and vehicle manifests. NASA understands this need, and 

has developed an excellent engineering assessment process that provides an estimate of 

possible CSCS duration. 

The International Space Station Program completed a study of the ability to support a one 

fault tolerant CSCS capability, and presented these recommendations to the Space Flight 

Leadership Council on June 9, 2004. The ISS Program has defined the following ECLSS 

functions as critical: carbon dioxide (CO2) control and disposal, oxygen (O2) generation and 

supply, water supply and recovery, and waste management.2 The ISS Program’s June study 

ISS Contingency Crew Support (in support of STS TPS Anomaly) Status presentation to the SFLC, 

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2 
Final Report of the Return to Flight Task Group 

concluded the ISS will be unable to meet one-fault tolerance in several important areas. Thus 

the CSCS capability is considered zero-fault tolerant overall, although some systems (e.g. 

temperature/humidity control and trace contaminant control) are as much as two-fault 

tolerant. Nonetheless, CSCS will not be a certified capability, since the ISS is only certified 

for a crew of six on a temporary basis and a crew of three on a permanent basis (without 

Space Shuttle support). Also, NASA is assuming that “STS-114 will require no newly 

developed Shuttle or ISS performance capabilities to enable CSCS.”3 

It is also important to recognize that NASA is scoping CSCS possibilities “in-house,” and will 

not coordinate formally with the Russian Federal Space Agency (FKA) to extend FKA 

commitments beyond their current levels. The FKA has explicitly stated that it does not 

endorse the CSCS concept. The basis of the FKA position is an operational philosophy – 

advanced by the United States – that rejects having any more crew aboard ISS than there are 

“lifeboat” seats available for. The FKA did not comment on the adequacy of ISS consumables 

to support the CSCS plan. Furthermore, through informal discussions, NASA analysts are 

aware that their Russians counterparts believe there is unexploited margin in the estimated 

performance of their systems. 

NASA published an L-1-month assessment that included an estimated CSCS duration for 

STS-114 of 43 days, given a May 15, 2005 launch.4

 NASA will revise this analysis as the 

status of systems and consumables aboard the ISS, Progress schedules, and STS-114 launch 

date vary. The engineering duration estimate is not, however, a stable figure; it can fluctuate 

as a result of changes in several conditions to which it is particularly sensitive, including: 

• Progress [Russian ISS supply vehicle] schedule, which directly affects the levels 

of consumables aboard the ISS; 

• Space Shuttle launch schedule, which likewise drives consumable levels and 

requirements; 

• Current operational status of all environmental systems aboard the ISS, and the 

occurrence of failures in these systems; 

• Plans for and assumptions about crew consumption; and 

• Plans for, and assumptions about, Space Shuttle manifests, particularly 

regarding spares and consumables. 

The fluidity inherent in the engineering estimate is mitigated to some extent by the fact that 

the prediction rests as much as possible on U.S. systems, and makes very conservative 

estimates about the performance of Russian systems (or omits them from consideration 

altogether). Moreover, the duration estimate could likely be extended through power-downs, 

resource-saving measures, and additional supplies/spares. Regardless, the stability and 

validity of the engineering estimate depends on good coordination and information flow 

between the International Space Station Program and the Space Shuttle Program. 

June 9, 2004. 3 NASA’s Implementation Plan for Space Shuttle Return to Flight and Beyond, (Tenth Edition, June 3, 

2005, p. 2-6). 4 According to NASA, “ISS ECLS engineering team has evaluated all of the critical ISS ECLS 

systems. Based on the current system status, past history, and current on-orbit consumables, the 

limiting system is oxygen supply, which can provide a 43-day CSCS TPS duration support.” (“STS114 (LF-1) L-1 Month Duration Report of the Environmental Control and Life Support Systems 

(ECLSS) Contingency Shuttle Crew Support (CSCS) for Thermal Protection System (TPS) Failure,” 

March 2005, p. 24.) 

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Overall, the RTF TG believes that CSCS protocols must rest on a thorough engineering 

analysis that specifies the parameters under which CSCS is likely to be technically possible. It 

is our assessment that NASA has developed and demonstrated a sound approach to such an 

analysis. 

3.16.4.3 Condition 3: Rescue Space Shuttle 

Invocation of CSCS necessitates a rescue mission. For STS-114 and STS-121, the Space 

Flight Leadership Council has mandated that the Space Shuttle Program be able to launch a 

rescue mission within the ISS engineering estimate of CSCS duration. In the event of CSCS, 

NASA has developed a plan for launching a rescue Space Shuttle that would have a crew of 

four, and would return with the stranded Orbiter crew within the duration defined by the ISS 

Program. If evacuating the ISS becomes necessary as a result of depletion of ISS systems and 

consumables, the ISS crew would return via the Soyuz spacecraft already docked at the ISS. 

Since only one Orbiter can dock to ISS, safe undock and de-orbit procedures for the damaged 

Orbiter are also necessary. The JSC Mission Operations Directorate has developed procedures 

for undocking an unmanned Orbiter from the ISS, separating to a safe distance, and then 

conducting a de-orbit burn to dispose the damaged Orbiter into an uninhabited oceanic area. 

These procedures have been exercised successfully in a joint integrated simulation involving 

flight controllers and flight crews from both the ISS Program and the Space Shuttle Program. 

The Task Group’s assessment is that NASA understands these processes well, and the RTF 

TG has confidence in their capability to execute them. The prominent concern associated with 

the launch of a rescue Space Shuttle is that it requires exposing the rescue Orbiter to the same 

potential for sustaining damage as that which stranded the primary vehicle. NASA is aware of 

this risk, although, as noted above, no formal assessment of this risk can be performed until 

the specific cause of the damage to the primary vehicle has been determined. 

3.16.4.4 Condition 4: Launch Decision Process 

The requirement to launch a rescue Space Shuttle imposes a need for NASA to address CSCS 

in its launch decision process, because it will have to specify the timeframe within which 

STS-300 must be ready to launch and CSCS requires coordination between the Space Shuttle 

Program and the International Space Station Program. CSCS processes are documented in a 

Memorandum of Agreement between the programs, which jointly analyze and report CSCS 

capabilities at L-6 months, L-3 months, L-1 month, and the L-2 week Flight Readiness 

Review. Updates to the estimate will be provided at the L-2-day and L-1-day MMT meetings, 

the L-9 hour pre-tanking meeting, and final go/no-go poll during the T-9 minute hold. If 

failures are reported during any of these updates, the MMT will assess their impact, and 

decide whether to continue or scrub the launch. NASA does not intend to write launch 

commit criteria to automatically abort a launch for late ISS failures which might create a gap 

in CSCS capability. 

It is the RTF TG’s assessment that the process for reporting and updating CSCS capability in 

the period before launch is appropriate. 

3.16.4.5 Condition 5: MMT Capability 

NASA asserts it will implement CSCS only upon clear evidence of catastrophic TPS damage 

that cannot be repaired. It has also determined that a CSCS decision will be made at the 

agency level, supported by MMT recommendations. The decision process by which the MMT 

would arrive at a CSCS recommendation is extremely difficult, and the potential 

consequences of CSCS implementation are momentous. Thus, invocation of CSCS requires 

complex risk-versus-risk assessments regarding whether to repair, entry, or launch a rescue 

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Space Shuttle that are fraught with uncertainty and ambiguity. To reduce uncertainty, these 

decisions will require the rapid assessment of data from multiple sources. To reduce 

ambiguity, these decisions will require close collaboration among MMT members to develop 

a common view of the severity of the risks. 

Given how central these decisions about repair, entry, CSCS, and rescue are to the NASA risk 

architecture, and how challenging this decision process would be, the RTF TG believed that it 

was important for the MMT to exercise and demonstrate this decision-making and analytic 

process prior to flight. The RTF TG asked NASA to “demonstrate the MMT process to weigh 

and evaluate the risk of CSCS relative to other options in an integrated simulation; 

demonstrate how the MMT will build a rationale for launching the rescue vehicle; and 

demonstrate the MMT, MER, and FCT process to evaluate and consider unintended 

consequences resulting from calling CSCS.” 

NASA believed they had fulfilled the RTF TG request during an MMT simulation held in 

early March, 2005 (sim #12). According to the simulation supervisor, the objectives of the 

sim included analysis of tile damage and decision-making with regard to repair and the 

possibility of CSCS. The simulation supervisor was satisfied with the MMT performance 

relative to this stated intent. Likewise, the chair of the MMT believed the MMT thought 

carefully about the implications of repairing the TPS versus invoking CSCS. While MMT sim 

#12 was a very important exercise that did appear to enhance the capacity of the MMT 

overall, RTF TG observers present during the simulation witnessed little systematic 

discussion with regard to CSCS specifically, and believed that NASA failed to fully confront 

– and ultimately make – the central, difficult risk-risk choices given circumstances where 

damage cannot be fully assessed, repairs may not be reliable, and a rescue launch may sustain 

similar debilitating damage. The minutes from the MMT meetings during the simulation also 

revealed little such discussion. Furthermore, the RTF TG discovered that the ISS team 

contribution to the MMT sim #12 scenario was relatively static, so that little discussion of the 

impacts on CSCS of the extra consumables used during the planned tile repair was possible. 

Based in part on these concerns, NASA subsequently added another MMT simulation (sim 

#13) to the schedule, with the objective of completing the scenario that was started in MMT 

sim #12. Making the critical choice of whether or not to ride a repair to the ground, and 

performing the risk-versus-risk analysis in the process, were the driving goals for this 

simulation. In the end, the MMT did review pertinent risk for the major options, and did a 

greatly improved job of evaluating the CSCS/LON option. Critical factors related to CSCS 

duration were discussed, and the view of CSCS as a last-resort option was appropriately held 

by the MMT members. In the end, the MMT unanimously decided to attempt the return from 

orbit with the uncertified tile repair, but the rationale for this decision was logically and 

thoroughly discussed. 

3.16.4.6 Conclusion 

While the RTF TG believes weaknesses remain in NASA’s demonstration of their capacity to 

handle a CSCS decision, the MMT clearly has made important progress since the loss of 

Columbia, and its overall decision-making ability is much improved. The RTF TG believes 

the MMT is capable of addressing a CSCS decision appropriately. 

The Task Group’s assessment of NASA’s actions was completed at the June 8, 2005, meeting. 

The RTF TG commends the Agency for its excellent work on SSP-3, and believes that NASA 

set a raising the bar goal for itself and exceeded that goal by a significant margin. 

3.16.5 RTF TG Observation 

RTF TG Observations concerning the MMT role in CSCS are provided in Section 3.11. 

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4 TRANSITION TO THE ASAP 

The Aerospace Safety Advisory Panel (ASAP) is a senior advisory committee that reports to 

the NASA Administrator and Congress. The Panel was established by Congress after the 

Apollo 204 Command Module (“Apollo 1”) spacecraft fire in January 1967 to advise NASA 

on the safety of operations, facilities, and personnel. 

The statutory duties of the ASAP, as prescribed in Section 6 of the NASA Authorization Act 

of 1968, Public Law 90-67, as amended, 42 U.S.C. 2477, are: 

“The Panel shall review safety studies and operations plans that are referred 

to it and shall make reports thereon, shall advise the Administrator with 

respect to the hazards of proposed operations and with respect to the 

adequacy of proposed or existing safety standards, and shall perform such 

other duties as the Administrator may request.” 

The ASAP consists of nine members appointed to two year terms, reaffirmed annually, by the 

NASA Administrator. The NASA Chief Safety and Mission Assurance Officer participates as 

an ex-officio member in Panel activities. The ASAP meets as a group four times per year, and 

conducts independent fact-finding as needed. 

Given that the ASAP meets only quarterly, and has no full-time investigative staff, the RTF 

TG recognizes that this volume of forward work may be beyond the resources of the ASAP. It 

is possible that ASAP may be assisted by other independent entities to assess the Agency’s 

performance of the tasks described in the subsequent sections. For example, the ASAP could 

make arrangements with the NASA Engineering and Safety Center (NESC), the Independent 

Technical Authority (ITA), the National Research Council, the National Academies, or other 

independent organizations to assist in its evaluations. 

4.1 Conditions for Transition 

It became clear early-on that the ASAP would ultimately become involved with monitoring 

the NASA implementation of the Columbia Accident Investigation Board (CAIB) 

recommendations. The RTF TG was responsible for assessing only the CAIB 

recommendations marked “return to flight,” and the Task Group limited itself to this subset of 

15 items. The remaining 14 (non-return to flight) CAIB recommendations, as well as other 

findings, observations, and NASA “raising the bar” actions would need to be assessed by 

another organization, such as the ASAP. CAIB believed that all 29 of their recommendations 

captured “thinking on what changes are necessary to operate the Shuttle and future spacecraft 

safely in the mid- to long-term.” While the RTF TG, by charter, focused solely on CAIB 

return-to-flight recommendations, the CAIB report focused more broadly on the needs of the 

Space Shuttle and future program needs. 

As the RTF TG completed their assessments, it also became apparent that some of the returnto-flight implementations contained forward work that would require monitoring by another 

organization, and the RTF TG negotiated a Memorandum of Agreement with the ASAP to 

continue this work. In the case of the return-to-flight recommendations, the RTF TG only 

assessed those portions of the NASA implementation that was specifically intended for 

STS-114 – any future work was largely outside the scope of the Task Group. The conditions 

that predicated a need to transition a CAIB recommendation to the ASAP were: 

1. A CAIB recommendation had a phased implementation approach, some being 

implemented before return-to-flight and some planned for implementation 

afterwards. For those phases of implementation not planned for STS-114, the 

ASAP will need to monitor and evaluate the future implementation. 

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2. The implementation of a CAIB recommendation will be available for the returnto-flight, but the implementation needs to be demonstrated in the flight 

environment. An example includes the reduction of debris shedding from the 

External Tank. Since the RTF TG completed its assessments prior to STS-114, 

the ASAP will have to assess the results of the flight data to verify the 

performance is as expected. 

3. A CAIB recommendation has a temporary implementation for STS-114 which 

cannot be used on a specific later flight, such as the proposed Hubble servicing 

mission. While the RTF TG has assessed the STS-114 implementation, the 

ASAP will need to monitor and evaluate the final implementation. 

To assist in the turnover of activities from the RTF TG to the ASAP, several ASAP members 

were invited to observe the final two plenary meetings of the Task Group and witnessed at 

least one Mission Management Team (MMT) simulation. The turnover is also assisted by the 

fact that two Task Group members (Dr. Dan L. Crippen and Dr. Amy K. Donahue) are also 

members of the ASAP. 

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4.2 Items to be Transitioned 

Several of the CAIB return-to-flight recommendations contain items the RTF TG believes the 

ASAP should continue to monitor. In addition, the Task Group has several items – not related 

to specific recommendations – that it believes require future monitoring or assessment. The 

ASAP might also wish to review the “RTF TG Observation” portion of each assessment. 

4.2.1 Integrated Vehicle 

The STS-114 Operations Integrated Plan for Thermal Protection System Assessment (or 

simply, the OIP) and its Damage Assessment Annex greatly enhanced the ability of the Space 

Shuttle Program to perform an integrated vehicle external damage assessment in support of 

decision-making, primarily within the MMT. The RTF TG believes that NASA should 

continue to develop the OIP and it’s Annex for all future flights, not just for STS-114. The 

information, understanding, and experienced gained from producing the document for 

STS-114 will be invaluable for future mission data integration. The ASAP should monitor the 

continued development of the OIP and its Annex, as well as how the processes and timelines 

described in the documents are used for decision-making within the MMT and other groups. 

4.2.2 CAIB Recommendation 3.2-1, External Tank Debris Shedding 

Debris from the External Tank was the physical cause of the Columbia accident, and NASA 

has gone to tremendous lengths in their attempts to cure the problem. According to the NASA 

May 2005 document The Integrated Risk Assessment Approach for Return to Flight, “... The 

External Tank debris allowable requirements currently do not protect against catastrophic 

damage of the Orbiter Thermal Protection System.” NASA developed a three-phase approach 

to correcting the flaws in the External Tank; Phase 1 was implemented for return-to-flight and 

Phase 3 has been deferred because of the pending 2010 retirement date for the Space Shuttle. 

Phase 2 is currently slated as post-return-to-flight work, and the RTF TG believes the ASAP 

should closely monitor the implementation of these changes. 

In addition, each of the tanks being used on the first eight launches was substantially 

completed prior to 2003 and has been modified – at least in the details – differently. 

Therefore, each is somewhat unique in its configuration. Although NASA plans to use data 

from the STS-114 flight to further characterize debris from the ET, it is possible that these 

differences will require additional data collection from future missions. 

The RTF TG believes the results of analyses conducted after the STS-114 launch should be 

closely monitored, as well the applicability of any anomalies to the tanks scheduled for future 

missions. The ASAP should continue to track the Program’s efforts to eliminate critical debris 

by aggressively working off the limitations documented in NSTS 60555, Verification 

Limitations for the External Tank Thermal Protection System . 

The Task Group suggests the ASAP monitor the continued use of the labor-intensive thermal 

protection system application processes enacted for the return-to-flight. 

4.2.3 CAIB Recommendation 3.3-1, Reinforced Carbon-Carbon Non-Destructive 

Inspection 

Understanding the condition of the RCC panels used on the Orbiter is essential for safe flight 

operations. NASA has identified future work including finishing the documentation of flightto-flight inspections in the Operations and Maintenance Requirements Document (OMRSD) 

and competing the development of applicable non-destructive inspection standards. 

The RTF TG believes the ASAP should monitor the Agency’s progress toward finishing the 

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documentation, and also ensure that meaningful non-destructive inspections continue for the 

remainder of the Space Shuttle Program. The Task Group is also concerned that NASA has 

only a single ship-set of spare RCC panels in inventory; something made troublesome by the 

long lead-times involved in manufacturing additional panels. 

4.2.4 CAIB Recommendation 3.3-2, Orbiter Hardening 

NASA decided to implement this recommendation in three phases. The first phase of changes 

to the Orbiters has been completed in time for STS-114. The second phase consists of two 

changes which could not be completed in time for the return to flight. They are the completion 

of the remaining “sneak flow” protection changes on RCC panels 1-4 and 14-22, and main 

landing gear door perimeter tile material change. The risk analysis of the tile damage 

tolerance indicated that the main landing gear door is one of the critical areas with which to 

deal. According of the NASA May 2005 document, The Integrated Risk Assessment 

Approach for Return to Flight (p. 11), their “ ... goal was to demonstrate that the capability of 

the Orbiter greater than the expected debris environment; however, we fell short in a number 

of cases.” 

It is important for the ASAP to monitor the progress of the BRI-18 tile material certification 

and the completion of this change on all three Orbiters. The third phase involves more 

extensive changes to the Orbiters, but these are being reconsidered in light of the scheduled 

2010 end of the program. 

Future work that NASA has identified includes continuing the verification of the analytical 

models used in determining the impact resistance of the Orbiter, as well as the continuing 

refinement of the definition for “critical debris.” The RTF TG believes the ASAP should 

monitor the progress of each of these items, with particular attention on model verification 

and configuration management. Abandoning future upgrades to the Orbiter may be 

appropriate given the limited number of missions expected to be flown, but an independent 

assessment of this approach should be carried out. ASAP should review the correlation of the 

remaining risk of damage to potential future Orbiter hardening concepts. 

4.2.5 CAIB Recommendation 3.4-1, Ground-Based Imagery 

Future work that NASA has identified for this recommendation includes the continued 

refurbishment and procurement of imagery assets at the Kennedy Space Center and the 

Eastern Range. The RTF TG believes that the ASAP should continue to assess the availability 

of adequate imagery assets to ensure there are three useful views of the Space Shuttle 

available for all future launches. 

4.2.6 CAIB Recommendation 3.4-2, High-Resolution Images of External Tank 

Future work that NASA identified for this recommendation includes installing additional 

cameras on the External Tank and Solid Rocket Boosters to provide better imagery of the 

Orbiter and its environment during ascent. The RTF TG believes that the ASAP should assess 

the implementation of the ET attach ring and SRB forward skirt cameras, along with the SRB 

solid-state recorders, planned for STS-115 and subsequent flights. 

4.2.7 CAIB Recommendation 3.4-3, High-Resolution Images of Orbiter 

NASA has predicated much of its return-to-flight planning on conducting detailed inspections 

of the Orbiter once it is on orbit. These inspections are accomplished, for the most part, using 

the Orbiter Boom Sensor System (OBSS) installed in the payload bay and photography from 

the International Space Station. 

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The RTF TG believes that the ASAP should continue to assess what constitutes “adequate 

resolution” as the Orbiter critical damage size evolves. Also, NASA only plans to use the 

OBSS for a limited number of flights; the ASAP should review the plan to discontinue its use 

and ensure that other adequate means exist to acquire the necessary imagery. 

4.2.8 CAIB Recommendation 4.2-1, Solid Rocket Booster Bolt Catcher 

The implementation of this item was straight-forward and has been completed. The RTF TG 

is satisfied that no ASAP involvement is needed. 

4.2.9 CAIB Recommendation 4.2-3, Closeout Inspection 

Ensuring that at least two people observe the final close-out of all Space Shuttle flight 

hardware provided additional assurances that processes were accomplished correctly. The 

NASA implementation of this recommendation seems complete and appropriate. However, 

the RTF TG believes that the ASAP should sponsor periodic monitoring to ensure the process 

is still being followed across the program, particularly as the program winds down. 

4.2.10 CAIB Recommendation 4.2-5, Kennedy Space Center Foreign Object Debris 

Definition 

The implementation of this item was straight-forward and has been completed. The RTF TG 

is satisfied that no ASAP involvement is needed. 

4.2.11 CAIB Recommendation 6.2-1, Consistency with Resources 

The RTF TG believes that NASA should devote continued attention to ensure undue schedule 

pressure does not arise. The Task Group further believes that the ASAP should monitor the 

NASA budget and workforce metrics to ensure sufficient resources are available to meet the 

Space Shuttle mission manifest, especially given the likely resource requirements of the new 

Vision for Space Exploration. 

4.2.12 CAIB Recommendation 6.3-1, Mission Management Team Improvements 

The Task Group believes that the ASAP should observe selected MMT simulations, with 

particular emphasis on team performance and the MMT processes and tools necessary to 

effect integrated time-sensitive critical risk-versus-risk trades and decisions. 

4.2.13 CAIB Recommendation 6.3-2, National Imagery and Mapping Agency 

Memorandum of Agreement 

The implementation of this item was straight-forward and has been completed. The RTF TG 

is satisfied that no ASAP involvement is needed. 

4.2.14 CAIB Recommendation 6.4-1, Thermal Protection System Inspection and 

Repair 

The ASAP should review the development of comprehensive autonomous (independent of 

ISS) inspection and repair capabilities; this is particularly important for non-ISS missions 

(i.e., Hubble Space Telescope Servicing Mission 4), but also protects against the possibility 

than an ISS mission fails to achieve the correct orbit, fails to dock successfully, or is damaged 

during or after undocking. Even for nominal ISS missions, NASA has work remaining in the 

inspection and repair areas; the Task Group believes that the ASAP should closely monitor 

these efforts. With the suspension of CSCS and rescue missions after the first few flights, the 

issue of a certified and operational inspection and repair capability must be addressed. The 

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Task Group feels that the ASAP should make this a high priority when reviewing the Space 

Shuttle Program. 

As the Task Group currently understands the situation, the Space Shuttle Program intends to 

discontinue the use of OBSS three or four flight after STS-114. In the view of the Task 

Group, this would require that other methods of detecting damage – such as the wing leading 

edge sensors – would have to be elevated from “Criticality 3” status to “Criticality 1.” 

The Task Group feels that ASAP should assess progress with respect to selecting, developing, 

and certifying long-term RCC and tile repair capabilities. 

4.2.15 CAIB Recommendation 9.1-1, Detailed Plan for Organizational Change 

While the CAIB did not make specific “cultural” change recommendations (other than three 

specific recommendations to be included in the plan required for R9.1-1), they provided 

numerous pages of text, findings, and observations to underscore their concerns in this area. 

To their credit and in response, over the past 29 months, NASA revised some pre-Columbia 

initiatives and undertook many other new initiatives (both for the Space Shuttle Program and 

NASA wide) to address the CAIB concerns. As the scope of these initiatives were beyond the 

RTF TG charter, the Task Group recommends that ASAP might wish to discern how these 

varied initiatives fit into an integrated senior leadership plan or vision. For the future, it is 

critical that NASA establish a foundation that can carry its vision forward. 

4.2.15.1 CAIB Recommendation 7.5-1, Independent Technical Authority 

The ASAP should monitor the progress toward completing the establishment of the ITA and 

its Technical Warrant Holders, whether the ITA is working as CAIB intended, whether the 

CAIB organizational concept is workable, and whether the “independent” funding sources are 

working. Additionally, the ASAP should monitor the process by which NASA grants waivers 

to technical requirements to ensure it meets the intent of the CAIB recommendations 

4.2.15.2 CAIB Recommendation 7.5-2, Safety and Mission Assurance 

ASAP should monitor to ensure SMA continues to be an “independent” voice, and the 

Agency’s alternative implementation of “direct line authority” will require continued ASAP 

oversight. Since the Space Shuttle Program SMA Manager is a voting member on the MMT 

(but does not possess “suspension authority”), further ASAP monitoring might be prudent to 

verify that those Center and SMA Directors with “suspension authority” recognize their 

responsibility and authority and are willing to use it if needed. In addition, ASAP needs to be 

cognizant of the historical trend to diminish the SMA role. Over time, without continued 

Headquarters leadership emphasis on the importance of the SMA role (including Quality 

Assurance), NASA history unfortunately portends that SMA roles become diminished. 

4.2.15.3 CAIB Recommendation 7.5-3, Systems Engineering and Integration 

The ASAP should assess the progress toward establishing a truly effective Systems 

Engineering and Integration Office. Items remaining include demanding rigorous 

documentation that sustains effective systems integration and engineering, and requiring 

improvements in standards for (and standardization of) validation, verification, and 

certification requirements for the development and use of analytical models. 

4.2.16 CAIB Recommendation 10.3-1, Digitize Closeout Photos 

The implementation of this item was straight-forward and has been completed. However, the 

RTF TG believes that, periodically, the ASAP should evaluate the digital imagery database 

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and closeout photography procedures at the Kennedy Space Center and other NASA 

installations to ensure its continued effectiveness. Should the Shuttle Program be extended 

past 2010, the decision for no further non-critical updates to the drawings should also be 

reconsidered. 

4.2.17 SSP-3, Contingency Shuttle Crew Support 

Because of the risks entailed, and the most-likely negative programmatic effects, the Task 

Group believes that CSCS should never be relied upon to overcome risks that could have been 

mitigated by other actions. The CSCS capability should be used only in the most extreme 

emergency where there is no other viable option for saving the crew of a stricken Orbiter. 

The Task Group believes the ASAP should conduct an independent evaluation of the 

desirability of maintaining a CSCS capability for flights after STS-121. If the capability does 

continue into the future, the ASAP should ensure that it does not become a “crutch” for the 

program and lead to a tendency toward negative changes to the flight rules and operations. 

LC-39B. 

Discovery sitting at 

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Final Report of the Return to Flight Task Group 

hangs in 

the VAB as it is 

ith 

Discovery

being removed from 

its original External 

Tank in the Vehicle 

Assembly Building at 

KSC. The Orbiter 

was later mated w

ET-121 prior to the 

launch of STS-114. 

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5 THE RETURN TO FLIGHT TASK GROUP 

On February 1, 2003, the Space Shuttle Columbia disintegrated while returning to Earth 

during the STS-107 mission, killing the crew of seven. Within hours, the independent 

Columbia Accident Investigation Board (CAIB) was appointed to determine the cause of the 

accident. What followed was, perhaps, the most far-reaching accident investigation ever 

conducted. The CAIB released the first volume of their final report on August 26, 2003, 

containing 29 specific recommendations for changes to the vehicle, the Space Shuttle 

Program, and to NASA in general. Among those recommendations were 15 that the accident 

board believed should be implemented prior to returning the Space Shuttle fleet to flight. 

On April 14, 2003, then-NASA-Administrator Sean 

O’Keefe wrote Lt. Gen. Thomas P. Stafford, U.S. Air The Columbia 

Accident Force (Ret.), requesting that the Stafford Task Force on Investigation Board International Space Station Operational Readiness initiate final report was 

issued on August 26, 

2003. 

an assessment of NASA’s plans to return the Space 

Shuttle to flight. The Stafford Task Force is a standing 

group chartered by the NASA Advisory Council, an 

independent advisory group to the NASA Administrator. 

One month later Lt. Gen. Stafford responded to the 

Administrator with a plan to activate a sub-organization 

with Col. Richard O. Covey, U.S. Air Force (Ret.), 

leading the day-to-day effort of conducting an 

independent assessment of the 15 CAIB return-to-flight 

recommendations. As a result, on July 18, 2003, a Return 

to Flight Task Group (RTF TG) was chartered under the 

Federal Advisory Committee Act with Lt. Gen. Stafford and Col. Covey as co-chairs. 

Over the course of the past two years, using expertise from the aerospace industry, federal 

government, academia, and the military, the RTF TG assessed the actions taken by NASA to 

implement the CAIB return-to-flight recommendations. During this time the Task Group 

conducted fact-finding activities, reviewed documentation, held public meetings, reported 

their assessments to the Space Flight Leadership Council, and released three interim reports 

on the progress toward launching the first Space Shuttle mission since the Columbia accident, 

designated STS-114. The assessments of the Task Group, although based primarily on data 

provided by the Space Shuttle Program, are independent of that program and are intended to 

provide the NASA Administrator an evaluation of the progress NASA has made toward 

meeting the intent of the 15 CAIB return-to-flight recommendations. 

As the Task Group delivers this final report to the NASA Administrator, Congress, and the 

American public, we take this opportunity to reemphasize that this report is strictly advisory 

and is not a prerequisite for returning to flight. Only NASA can make the determination if the 

vehicle, supporting infrastructure, and organization are sufficiently robust to resume flying. 

5.1 Federal Advisory Committee Act 

NASA is among several federal agencies that access the insights and experiences of 

accomplished citizens by establishing advisory committees. The Federal Advisory Committee 

Act (FACA – Public Law 92-463 as amended; 5 U.S.C. App. §§1 et seq) governs the creation, 

management, and termination of such advisory committees when they report directly to 

federal officials. The General Services Administration provides government-wide 

administrative guidance for FACA, while the Office of Government Ethics oversees “conflict 

of interest” matters associated with the designation and conduct of advisory committee 

members. 

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For the purposes of the FACA, the RTF TG was composed of two voting Co-Chairs and 

multiple voting members. In addition, the Task Group had one non-voting ex-officio member 

– the NASA Deputy Chief Safety and Mission Assurance Officer. The Executive Secretary of 

the Task Group was a Civil Service employee who performed as the Designated Federal 

Official required by the FACA. 

None of the voting members were NASA employees. However, the Co-Chairs and some 

members were appointed as Special Government Employees under the federal personnel 

system. All members were reimbursed for travel expenses in accordance with normal 

government policy. 

Under the FACA, the members can not have any vested interest in the outcome of the 

assessment. The NASA General Counsel determined that the members of the RTF TG had no 

interest that would prevent them from exercising individual or representative judgment. 

5.2 Purpose and Duties of the Task Group 

The RTF TG was chartered to perform an independent assessment of NASA’s actions to 

implement the CAIB return-to-flight recommendations. However, this assessment is strictly 

advisory, and NASA remains responsible for the overall safety and operational readiness of 

STS-114 and all subsequent Space Shuttle missions. Perhaps as important as what the Task 

Group was asked to do, is what it was not asked to do: 

1. The Task Group was not asked to pass judgment on the appropriateness or 

validity of the CAIB recommendations. 

2. The Task Group was not asked to pass judgment on the methods chosen by 

NASA to implement the recommendations (i.e., were the selected methods 

the best); we were only asked to assess whether the selected methods met 

the intent of the CAIB recommendation. 

3. Other than assessing the return-to-flight schedules for “undue pressure,” the 

Task Group was not asked to pass judgment on when the return-to-flight 

mission should occur. 

To fully understand the intent of the accident board, the RTF TG conducted fact-finding 

interviews with former members and staff from the CAIB. The Task Group did not, however, 

attempt to assess the adequacy or appropriateness of the CAIB recommendations. 

The Task Group has also made several independent observations on safety and operational 

readiness that it believes are appropriate. 

The RTF TG relied on the expertise of its members and other sources to provide this 

assessment. Fact-finding was accomplished using written data and briefings supplied by 

NASA and its contractors, meetings with other persons and organizations as deemed 

appropriate, and site visits to NASA and contractor facilities. In carrying out its 

responsibilities, the Task Group: 

• Focused on the Agency’s actions to implement the 15 CAIB return-to-flight 

recommendations as related to the safety and operational readiness of STS-114. 

• Used, as it deemed appropriate, the Space Shuttle Program Office and Space 

Shuttle Return to Flight Planning Team, working groups, and supporting 

facilities to conduct the assessment. These included staff advisors, as required, 

for expertise in such areas as engineering, public affairs, law, and security. 

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• Analyzed the facts and opinions considered relevant in the CAIB final report 

and reviewed the supporting documents and databases as needed. 

• Documented and reported RTF TG assessment findings in public meetings, 

three interim reports, and a final report. 

In addition to the 15 return-to-flight recommendations made by the CAIB, after the April 

2004 plenary meeting the Task Group notified NASA of its intention to assess one additional 

“raising the bar” action that NASA assigned itself as part of its return to flight efforts. This 

task, called SSP-3, Contingency Shuttle Crew Support, is documented in NASA’s 

Implementation Plan for the Space Shuttle Return to Flight and Beyond. Essentially, this 

“raising the bar” action addresses the use of the International Space Station as a safe haven for 

a Space Shuttle crew in case an Orbiter is damaged and deemed unsafe for entry. Because of 

the potential for this being a mitigating or supportive capability for return to flight, the Task 

Group felt the need to formally assess NASA’s actions relative to establishing the capability. 

The CAIB had indicated that NASA need only develop a detailed plan to change certain 

aspects of its organization prior to return-to-flight. However, because the return-to-flight 

activities have taken much longer than the CAIB anticipated, NASA has had the opportunity 

to begin implementing the planned reorganization. Therefore, in addition to R9.1-1 (which the 

CAIB marked as a return-to-flight item), the Task Group is assessing the progress made on 

the three organizational recommendations (R7.5-1, R7.5-2, and R7.5-3). These three CAIB 

recommendations are assessed within the context of the R9.1-1 planning recommendation and 

may be found in that section of this report. 

Aside from the one non-CAIB-recommendation noted above, the RTF TG did not assess any 

other Space Shuttle Program hardware, software, processes, organizations, or procedures. For 

instance, the Task Group did not evaluate the readiness or safety of the Space Shuttle Main 

Engines, Solid Rocket Boosters, auxiliary power units, fuel cells, or other element hardware. 

Nor did the Task Group assess the PASS or BFS flight software. It is NASA, and NASA 

alone, that can adequately evaluate the Space Shuttle Program as a whole and determine its 

readiness to resume flying. 

5.3 Organization of the Task Group 

The RTF TG membership consisted of select representatives from the Stafford Task Force on 

International Space Station Operational Readiness, under which it was chartered, and 

additional members selected by the Co-Chairs and appointed by the NASA Administrator. 

These members provided a knowledge base appropriate to the assessment of NASA’s 

implementation of the CAIB return-to-flight recommendations. 

After reviewing the nature of the CAIB recommendations, the RTF TG organized itself into 

three panels: the Management Panel, Operations Panel, and Technical Panel. Subsequently, an 

Integrated Vehicle Assessment Sub-Panel and Editorial Sub-Panel were established for 

specific tasks. Each of the Panels was responsible for leading the assessment of specific CAIB 

recommendations, and prepared a final presentation for the assembled Task Group to detail 

NASA’s implementation of each recommendation in preparation for the final deliberations 

and vote. 

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5.3.1 Management Panel 

The Management Panel focused on the NASA compliance with the CAIB recommendations 

concerning Space Shuttle Program management, the return-to-flight integrated schedule, 

program/project risk management, and public safety policy. This assessment included CAIB 

recommendations: 

R6.2-1 Consistency with Resources 

R6.3-1 Mission Management Team Improvements 

R6.3-2 National Imaging and Mapping Agency Memorandum of Agreement 

R9.1-1 Detailed Plan for Organizational Change, including: 

R7.5-1 Independent Technical Engineering Authority 

R7.5-2 Safety and Mission Assurance Organization 

R7.5-3 Space Shuttle Integration Office Reorganization 

5.3.2 Operations Panel 

The Operations Panel focused on the NASA compliance with the CAIB findings and 

recommendations concerning Space Shuttle Program crew and controller operations, 

processing and launch operations, and procedures to support operations. This assessment 

included CAIB Recommendations: 

R3.4-1 Ground-Based Imagery 

R3.4-2 High-Resolution Images of External Tank 

R3.4-3 High-Resolution Images of Orbiter 

R4.2-5 Kennedy Space Center Foreign Object Debris Definition 

R6.4-1 Thermal Protection System Inspection and Repair (operations only) 

R10.3-1 Digitize Closeout Photos 

SSP-3 Space Shuttle Program Action – Contingency Shuttle Crew Support 

5.3.3 Technical Panel 

The Technical Panel focused on the NASA compliance with the CAIB recommendations 

concerning the material condition of the Space Shuttle. This included the development of and 

compliance with technical requirements, vehicle engineering, hardware and software 

development/verification, and overall vehicle certification status. This assessment included 

CAIB recommendations: 

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R3.2-1 External Tank Debris Shedding 

R3.3-1 Reinforced Carbon-Carbon Non-Destructive Inspection 

R3.3-2 Orbiter Hardening 

R4.2-1 Solid Rocket Booster Bolt Catcher 

R4.2-3 Closeout Inspection 

R6.4-1 Thermal Protection System Inspection and Repair (system hardware 

development only) 

5.3.4 Integrated Vehicle Assessment Sub-Panel 

The Integrated Vehicle Assessment Sub-Panel combined insights from the Management, 

Operations, and Technical Panels to assess the ability of NASA to perform an integrated 

vehicle external damage assessment, based on a variety of imagery and sensor sources in 

support of decision-making during launch and flight. 

This sub-panel focused on cross-cutting vehicle assessment actions, specifically including an 

assessment of the Orbiter Thermal Protection System. The sub-panel assessment considered 

the broad interactions of allowable debris, critical damage size, damage detection and 

assessment via imagery and sensors, as well as the development of the Mission Management 

Team improvements needed to support real-time operations. This assessment included CAIB 

recommendations: 

R3.2-1 External Tank Debris Shedding 

R3.3-2 Orbiter Hardening 

R3.4-1 Ground-Based Imagery 

R3.4-2 High-Resolution Images of External Tank 

R3.4-3 High-Resolution Images of Orbiter 

R6.3-2 National Imaging and Mapping Agency Memorandum of Agreement 

R6.4-1 Thermal Protection System Inspection and Repair (integrated data flow 

only) 

R6.3-1 Mission Management Team Improvements 

SSP-3 Space Shuttle Program Action – Contingency Shuttle Crew Support 

5.3.5 Editorial Sub-Panel 

The Editorial Sub-Panel coordinated the preparation of the RTF TG interim and final reports. 

5.3.6 Staff and Other Personnel 

The Task Group maintained offices outside the Johnson Space Center in Houston, Texas, for 

use by the permanent staff and visiting members. The members generally worked out of their 

home offices except when on fact-finding trips or attending Task Group plenary and public 

meetings. 

The Executive Secretary performed as the Designated Federal Official (DFO) per FACA 

regulations by fulfilling all functions required by statute, including recordkeeping and 

compliance with FACA procedures. The DFO served as the Government’s agent for all 

matters related to RTF TG activities. 

Support personnel facilitated the Task Group fact-finding activities and were assigned to each 

panel and sub-panel. A NASA General Counsel was provided by the Johnson Space Center 

and was available for legal advice and interpretations concerning technical and programmatic 

issues relevant to the NASA implementation of the CAIB findings and recommendations. A 

NASA Public Affairs Officer from the Marshall Space Flight Center provided support to the 

Task Group and served as an interface with the news media and the public. Specialists, 

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contractors, consultants, and other personnel were provided to the RTF TG as needed during 

its assessment activities. Administrative, travel, and secretarial support was provided at the 

Houston office. Valador, Inc., of Herndon, Virginia, was retained as the Task Group supportcontractor to provide consultants, maintain the RTF TG web site, and other duties as needed. 

5.3.7 Personnel Changes 

As with any group that operates over a long period of time, personnel changes on the RTF TG 

were inevitable. In June 2003, as the Task Group was initially being organized, there were 20 

members of the Task Group; all except the ex-officio were voting members: 

Lt. Gen. Thomas P. Stafford, U.S. Air Force (Ret.), Co-Chair

Col. Richard O. Covey, U.S. Air Force (Ret.), Co-Chair

Col. James C. Adamson, U.S. Army (Ret.) 

Maj. Gen. William A. Anders, U.S. Air Force Reserve (Ret.) 

RADM Walter H. Cantrell, U.S. Navy (Ret.)

Mr. Benjamin A. Cosgrove 

Dr. Dan L. Crippen 

Mr. Joseph W. Cuzzupoli 

Dr. Charles C. Daniel 

Dr. Richard Danzig 

Gen. Ronald R. Fogleman, U.S. Air Force (Ret.) 

Col. Gary S. Geyer, U.S. Air Force (Ret.)

Maj. Gen. Ralph H. Jacobson, U.S. Air Force (Ret.) 

Mr. Richard H. Kohrs 

Mr. James D. Lloyd, ex-officio

Lt. Gen. Forrest C. McCartney, U.S. Air Force (Ret.) 

Mr. David Raspet

Mr. Seymour Z. Rubenstein

Mr. Robert B. Sieck

Mr. William Wegner 

By the end of July 2003, seven additional voting members who brought specific expertise had 

been added to the Task Group: 

Dr. Walter D. Broadnax 

Dr. Kathryn I. Clark 

Dr. Amy K. Donahue 

Ms. Susan M. Livingstone 

Dr. Rosemary O’Leary

Dr. Decatur B. Rogers 

Mr. Thomas N. Tate 

On September 12, 2003, it was announced that three new voting members had been added to 

the Task Group, bringing the total to 29 voting members and 1 ex-officio. 

Ms. Christine H. Fox

Col. Susan J. Helms, U.S. Air Force 

Dr. Kathryn C. Thornton

However, later during September 2003, two members resigned from the Task Group for 

personal reasons: 

Maj. Gen. Ralph H. Jacobson, U.S. Air Force (Ret.) 

Mr. David Raspet

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Since the Task Group still had a sufficiently broad cross-section of necessary skills, these 

members were not replaced. At this time, Dr. Dan L. Crippen took the Lead of the 

Management Panel formerly held by Maj. Gen. Jacobson. 

On May 3, 2004, NASA Headquarters reassigned the Task Group Executive Secretary, Mr. 

David Lengyel, to the Office of the Chief Engineer at Headquarters because it was felt his 

skills and expertise were needed in that office. Mr. Vincent D. Watkins, from the Johnson 

Space Center, succeeded him as Executive Secretary. 

In June 2004, RADM Walter H. Cantrell, U.S. Navy (Ret.) left the Task Group to become 

Deputy Chief Engineer for NASA’s new Independent Technical Authority. Since the CoChairs felt that the Task Group still had sufficient membership, no successor was named for 

RADM Cantrell. Dr. Charles Daniel replaced RADM Cantrell on the Integrated Vehicle 

Assessment Sub-Panel and Editorial Sub-Panel. 

In September 2004, Dr. Richard Danzig left the Task Group because “the press of other 

activities involving national security problems has left me without time to perform as a 

member of the Group.” Since the Task Group believed it was close to completing its 

activities, no successor was selected. 

The first representative from the Astronaut Office, Lt. Col. Carlos L. Noriega, U.S. Marine 

Corps (Ret.), left the Task Group after he received a flight assignment on STS-121 in 

December, 2003. Lt. Col. Noriega is currently the Manager of the Exploration Systems 

Engineering Office at the Johnson Space Center. He was replaced on the Task Group by Col. 

Michael J. Bloomfield, U.S. Air Force. 

Participation of at least 51 percent of the voting members was required to constitute a quorum 

of the Task Group. 

5.4 Relationship to the NASA Implementation Plan 

At the same time that the CAIB was conducting its investigation, NASA began pursuing an 

Agency-wide effort to improve human space flight. Part of this effort was taking a fresh look 

at all aspects of the Space Shuttle Program, from technical requirements to managerial 

processes. The outcome was a set of NASA-generated actions that complement the CAIB 

recommendations. These are documented in NASA’s Implementation Plan for Space Shuttle 

Return to Flight and Beyond. (For brevity, the RTF TG generally called this the NASA 

Implementation Plan.) 

The NASA Implementation Plan integrates both the 

CAIB recommendations and NASA-generated actions 

into a single document. Many of the NASA-generated 

actions “raise the bar” beyond what the CAIB 

recommended. With a single exception, the RTF TG 

did not assess these raising-the-bar actions – that 

exception is SSP-3, Contingency Shuttle Crew Support. 

It should be noted that some of the raise-the-bar items 

in the NASA Implementation Plan overlapped various 

CAIB requirements, but the RTF TG assessed the 

CAIB requirements as written. 

In general, the NASA Implementation Plan provides 

high-level description of the steps taken by NASA to 

implement the CAIB recommendations and the NASAgenerated actions. The implementation plan is revised 

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periodically, with the latest version being the Tenth Edition on June 3, 2005. The NASA 

Implementation Plan went from its December 3, 2004, “Revision C” to the March 18, 2005, 

“Ninth Edition.” This was explained to the Task Group as an attempt to correct the previous 

system of revisions that did not track intermediate releases (e.g., 1.1); there had been eight 

releases prior to March 2005, so this version was called the Ninth Edition. 

The RTF TG has not independently verified or validated any information contained in NASA’s 

Implementation Plan for Space Shuttle Return to Flight and Beyond. 

5.5 Conduct of the Assessment 

The diverse nature of the CAIB recommendations required a unique approach to the 

assessment of each item. This was a result of the presence of process enhancements, hardware 

modifications, organizational changes, and documentation revisions, often in a single item. In 

general, the lead panel conducted fact-finding through field trips to relevant sites, meetings 

with NASA personnel, discussions with contractors, issuing formal Requests for Information 

(RFI) to NASA, and consultations with other experts. 

5.5.1 Coordination with NASA 

NASA provided primary points-of-contact to manage the flow of information between the 

Task Group and the NASA community. Requests for fact-finding meetings, supporting data 

via Requests for Information (detailed in the next section) and coordination of schedules and 

product deliveries was filtered through these contacts. These NASA representatives also 

developed and provided the official input to the RTF TG for each recommendation in a 

closure package (this process is discussed further in Section 6.6). Meetings between NASA 

and the Task Group included formal briefings directly to the members and those where Task 

Group members were simply part of the audience of a regularly-scheduled meeting. 

All material provided to the RTF TG became a part of the permanent Task Group record. 

Some of this material will not be made available to the public because it contains data 

restricted under the International Traffic in Arms Regulations (ITAR, 22 CFR Parts 120-130) 

or company-proprietary information that the contractors have a right to protect under their 

existing agreements with NASA. All data not restricted by security, ITAR, or companyproprietary considerations were entered into the Process-Based Mission Assurance (PBMA) 

database to facilitate sharing among Task Group personnel. These data will be archived at the 

National Archives and Records Administration. 

5.5.2 Requests for Information 

The primary means of requesting and transmitting information between the Program Office 

and the Task Group was called a “Request for Information” form. This process was similar to 

that used by the CAIB to request data. An RFI could be a simple request for existing facts or a 

complex inquiry on operations. In response to an RFI, NASA could provide information, or 

make specific make presentations to the Task Group. The RTF TG intended that all RFIs be 

completed prior to final deliberations on individual return-to-flight recommendation 

assessments. 

When a Task Group member needed information, the member or staff completed an RFI 

form. This form detailed the information required, along with a date by which the information 

was needed. After the RFI was approved by the appropriate Panel Lead, it was logged into an 

RTF TG database. The RFI was then sent to the NASA point-of-contact via the NASA 

representative to the RTG TG. The NASA point-of-contact had the authority to accept or 

reject the RFI. Rejection was usually caused by the RFI being too broad and placing too great 

a burden on the NASA organization that was already working to implement the required 

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return-to-flight changes. If the NASA point-of-contact rejected an RFI, they worked with the 

Task Group member to revise the request, which was then resubmitted through the process. 

Once the NASA point-of-contact accepted the RFI, the request was transferred to the 

appropriate NASA organization. This information was then fed back to the RTF TG staff to 

update the tracking database. 

The assigned NASA organization developed a response that was then reviewed and approved 

by a process within NASA. A response to an RFI was only considered official when it was 

signed by designated officials of the Space Shuttle Program Office. At this point, the NASA 

point-of-contact sent the data to the RTF TG. If the information was deemed acceptable, the 

NASA point-of-contact and the RTF TG Panel Lead signed the RFI form for official closure. 

The RFI form and associated response was then uploaded into PBMA and the RTF TG 

tracking database was updated. 

5.6 Assessment Closure Process 

While the Task Group was conducting fact-finding activities, NASA was developing and 

implementing plans to satisfy the CAIB recommendations. When NASA was satisfied with its 

implementation, the Agency presented a Return to Flight Action Closure Package and its 

supporting documentation to the Task Group. These were auditable documents that chronicled 

NASA’s implementation of each CAIB return-to-flight recommendation. Each Return to 

Flight Action Closure Package contained, at a minimum, the following elements: 

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1. Signature sheet, including: 

a. Relevant element or project manager(s) 

b. Space Shuttle Program Manager 

c. Deputy Associate Administrator for International Space Station and 

Space Shuttle Programs 

d. Chief Safety and Mission Assurance Officer 

e. Space Flight Leadership Council Co-Chairs 

2. Transmittal letter from the Space Flight Leadership Council Co-Chairs to the RTF 

TG Co-Chairs 

3. Executive Summary, including: 

a. Background information (including assumptions and interpretation of 

the CAIB recommendation) 

b. Corrective measures and results 

c. Open issues 

d. Verification 

4. Presentation package for the RTF TG (including back-up charts) 

During the plenary meeting in April 2004, the Task Group had the opportunity to exercise this 

process for the first time. Although deemed generally successful, the process was further 

refined with the following changes: 

1. The definition of tasks, requirements, and results would be developed from the most 

recent release of the NASA Implementation Plan. 

2. The metrics and audit trail specified above would include the use of the current 

Space Shuttle Program Office configuration management system to provide tracking 

on any required: 

a. Test plans, results and reports 

b. Design data and documentation 

c. Programmatic documentation, including Directives, Actions, and 

Change Requests 

d. Documentation and documentation traceability, starting with the 

programmatic documentation, NSTS 07700 

e. Detailed audit trail and plan for these activities, but not the completion 

of activities prior to submittal for approval 

3. Agreements on the appropriate level at which to track, verify, and certify the 

activities to be included in the closure package. 

After being received, the Return to Flight Action Closure Package was evaluated by the 

appropriate RTF TG Panel(s). When the Panel(s) was satisfied that the package was complete, 

it reported to the full Task Group. While the presentation by NASA to the Panel was usually 

by teleconference, the Panel’s reporting to the full Task Group could be either by 

teleconference or during a face-to-face plenary. The process was the same regardless of the 

forum. 

At the conclusion of the deliberations, the RTF TG formally notified the Space Flight 

Leadership Council of the Task Group’s determination via correspondence; the assessment 

could be considered “closed” or “conditionally closed,” or it could remain open. If an 

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assessment was “conditionally closed,” the Task Group identified in the same correspondence 

what action or documentation was required for full closure. 

As the Task Group completed its activities, however, it was eventually recognized that this 

nomenclature was misleading. Both NASA and the press had interpreted the term “closed” as 

applying to the recommendation itself; the Task Group had no power, nor intent, to “close” a 

CAIB recommendation. Rather, it was the assessment being conducted by the Task Group 

that was either “open” or “closed.” In this context, “closed” meant that the Task Group’s 

assessment was complete. 

Although the three interim reports used different terminology, this final report uses a more 

appropriate nomenclature. By definition, all the Task Group’s assessments are now “closed” 

since the RTF TG has disbanded at the end of its charter. In each case, the determination is 

that the NASA implementation met the intent of the CAIB recommendation or that it did not 

meet the intent. 

5.7 Summary of Interim Reports 

The first two interim reports were prepared by the Editorial Sub-Panel, consisting of Dr. Dan 

Crippen, RADM Walt Cantrell, and Dr. Rosemary O’Leary. For the third interim report, 

RADM Cantrell was replaced by Dr. Charles Daniel. The Technical, Management, and 

Operations panels provided the primary substance of the reports. The reports were submitted 

for comments to the entire Task Group, and to NASA for technical review only. Co-Chair 

Col. Richard Covey approved the final version of each interim report prior to its release. 

The first interim report was released on January 20, 2004. This report presented the 

assessment status of each CAIB return-to-flight recommendation as of early 2004. All of the 

assessments were still open at this point in time. 

The second interim report was released on May 19, 2004, and it updated the assessment status 

of each recommendation. NASA had submitted closure packages for R3.3-1, R4.2-3, and 

R6.3-2, and the Task Group’s assessments of these recommendations were conditionally 

closed. The Task Group felt that there had been substantial progress across the board relative 

to all of the return-to-flight recommendations. To support this conclusion, the second interim 

report noted that several other recommendations were far enough along that the assessments 

could likely be closed at an anticipated August plenary. 

The third interim report was released on January 28, 2005, and it again updated the 

assessment status of each recommendation. The report noted that the assessment of R3.3-1, 

which had been conditionally closed in the second interim report, had not changed status. 

NASA had submitted five new closure packages, resulting in the assessments of R3.4-2, 

R4.2-1, R4.2-5, and R10.3-1 being fully closed and R3.4-1 being conditionally closed. NASA 

supplied additional data for R4.2-3 and R6.3-2, which had been conditionally closed in the 

second interim report, so the Task Group revised the status of its assessment in these cases to 

fully closed. 

At the conclusion of its final plenary meeting on June 27, 2005, the Task Group delivered a 

copy of the Executive Summary only to the NASA Administrator, and copies were 

transmitted to Congress and the White House. The Executive Summary was also posted to the 

Task Group’s web site for public distribution. The Executive Summary contained at the 

beginning of this Final Report is a slightly edited revision of the version released on July 27 – 

the edits were minor in nature and did not change the content. 

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on the Vehicle 

Center, Florida. 

The American flag 

Assembly Building at 

the Kennedy Space 

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6 SUMMARY OF THE RTF TG PLENARY MEETINGS 

Over the course of two years, the Return to Flight Task Group held 11 plenary meetings to 

discuss its assessment of NASA’s implementation of the Columbia Accident Investigation 

Board (CAIB) return-to-flight recommendations. Nine of these meetings were conducted 

face-to-face, and two were via teleconference. All of these included fact-finding sessions 

among the members, and eight included public meetings to deliberate results. The minutes of 

the public meetings are public record , and video and/or audio of the meetings is available on 

the RTF TG website. 

Three of the following summaries were previously published in the interim reports that were 

issued immediately after the meetings, and are provided here mostly verbatim (only minor 

editorial corrections). For that reason, they are written in the present tense, even though the 

events they discuss are long past. All of these descriptions discuss the events as they were 

presented at the time; many things have changed over the course of the Task Group’s work 

and the descriptions presented here do not necessarily reflect the current or final status. 

6.1 Summary of August 2003 Plenary 

This plenary was held August 5-7, 2003, at the Kennedy Space Center, Florida. This meeting 

was largely administrative in nature as the Task Group received briefings and developed 

operating procedures, plans, and schedules. During fact-finding, the Task Group received 

briefings from the Space Shuttle Program regarding its organization, vehicle processing, and 

the Certificate of Flight Readiness (CoFR) process. The Task Group received a presentation 

on the coatings used on the launch pad structures and their effects on the reinforced carboncarbon wing leading edge. NASA also provided a briefing on ascent imagery and 

the Agency’s preliminary plans regarding how to implement the CAIB imagery 

recommendations. The Space Shuttle Program Manager and his staff made a presentation 

explaining the purpose and scope of NASA’s Implementation Plan for Space Shuttle Return to 

Flight and Beyond [Revision 1 was current when this plenary was held] and NASA’s current 

schedule for implementing the CAIB recommendations. Following the fact-finding, the Task 

Group held its first public meeting. This event was covered by the news media and the Task 

Group introduced itself and discussed its roles and responsibilities. 

From the beginning, 

the Return to Flight 

Task Group was in 

the public eye. Here 

the news media, 

both print and 

broadcast, cover the 

Task Group’s first 

public meeting at the 

Debus Center, 

Kennedy Space 

Center Visitor 

Complex August 7, 

2003. The RTF TG 

was at KSC to 

conduct 

organizational 

activities, tour Space 

Shuttle facilities, and 

receive briefings on 

Space Shuttlerelated topics. 

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Return to Flight Task 

Group members 

participate in factfinding meeting in 

Houston September 

10, 2003. 

6.2 Summary of September 2003 Plenary 

This plenary was held September 9-11, 2003, in Houston, Texas. Again, this fact-finding 

meeting was partly administrative in nature, with the members receiving a briefing on the 

Freedom of Information Act (FOIA) and a presentation by the NASA Inspector General. In 

addition, NASA briefed the Task Group on the current status of NASA’s Implementation Plan 

for Space Shuttle Return to Flight and Beyond [Revision 1.1 was current when this plenary 

was held], and a discussion of each CAIB return-to-flight recommendation followed. NASA 

officials then provided a top-level overview of the approach they were using for return-toflight planning. The core objective was to eliminate critical debris from the External Tank, 

with a long-term goal of eliminating all debris. Additional efforts centered on imagery, 

inspection, and repair. The Task Group also discussed the roles and responsibilities of the 

three panels along with which assessment each panel would lead. Splinter fact-finding 

meetings dedicated to each panel occupied the remainder of the plenary. Since there were no 

items to deliberate, the Task Group did not hold a public meeting. However, members of the 

media were briefed during a teleconference. 

6.3 Summary of December 2003 Plenary 

This plenary was held December 9-11, 2003, in Houston, Texas. This meeting began, in 

earnest, the long road to assessing NASA’s implementation of the CAIB return-to-flight 

recommendations. 

The CAIB uncovered some very specific conditions that led to the demise of the Columbia 

along with process and management failures that contributed to the accident. In a sense, the 

loss of the Columbia was caused primarily by two faulty assumptions: 

Foam shed from the External Tank would be “transported” around the leading edge 

of the wing by the aerodynamics of the Orbiter; and, 

The foam was not substantial enough to develop a ballistic moment capable of 

puncturing the reinforced carbon-carbon on the wing leading edge. 

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It turns out that both assumptions – long-held and widely shared within NASA – were wrong, 

despite previous launches in which foam was shed and little damage was done, seemingly 

validating the assumptions. Thus, the “conditioned” response of senior managers to more 

junior members, who questioned these assumptions after the Columbia launched, was one of 

discouraging dissent and of comfort with established technical and operational assumption. 

The problem was exacerbated by systemic failures that prevented critical information getting 

to the right people at the right time. 

In this light, the technical and operational challenges for NASA are to rectify the 

consequences of these faulty assumptions by, for example, removing debris sources, 

enhancing photography, improving on-orbit inspections, and developing on-orbit Thermal 

Protection System repair. The primary challenge for the Agency’s management is to devise an 

organization with embedded processes to identify other faulty assumptions. 

The Return to Flight Task Group is charged with assessing the implementation of the CAIB 

recommendations. The RTF TG is not in the business of suggesting specific remedies. As one 

member put it, the Task Group is in the position of an umpire calling balls and strikes in a 

zone defined by the CAIB recommendations. The RTF TG is not in the position of evaluating 

the overall readiness or safety of the next flight, just the implementation of the CAIB returnto-flight recommendations. 

Because of the substantial changes to the foam insulation and inspection techniques for the 

External Tank, and the current lack of understanding of the foam shedding phenomena, the 

STS-114 ascent must be considered a test flight. As such, the RTF TG expects NASA to 

capture as much test data as possible during ascent, particularly in regard to the imaging 

recommendations of the CAIB. 

NASA has responded to all the recommendations the CAIB identified as necessary for 

accomplishment before the next Space Shuttle flight in NASA’s Implementation Plan for 

Space Shuttle Return to Flight and Beyond [Revision 1.1 was current when this plenary was 

held]. Not surprisingly, progress on the many recommendations has been uneven. Several of 

the technical responses to specific recommendations have indicated substantial progress, 

although none have been completed. Others, such as preparation of a detailed plan for the 

implementation of an Independent Technical Authority, are still in planning and some time 

away from implementation and a long time away from evaluation. 

While the tone of this interim report is justifiably positive, progress should not be mistaken 

for accomplishment. As time passes and the next scheduled flight approaches, the enormity of 

the remaining task looms. Detailed plans for many of the recommendations have not been 

forthcoming. NASA has not been timely in some of its responses to Task Group requests for 

information. And while some of the most critical organizational issues raised by the CAIB 

require only a “detailed plan” before return-to-flight, the RTF TG will be looking for plans 

and processes that will stand the test of time – not just suffice for the first launch – much as 

the hardware redesigns are expected to serve the life of the Space Shuttle. It is still much too 

soon to predict either the success of implementation or the timing of the next flight. 

A public meeting was held after this plenary and members of the media were briefed during a 

press conference. 

6.4 Summary of April 2004 Plenary 

This plenary was held April 12-16, 2004, in Houston, Texas. There had been several changes 

in NASA’s return to flight effort since the previous plenary meeting in December 2003. First, 

and most immediately, the schedule for the next launch was moved from September 2004 to 

March-April 2005. This schedule change was prompted by three developments: 

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1. Additional testing of the susceptibility of the Orbiter Thermal Protection System 

to damage, especially the reinforced carbon-carbon, coupled with advanced 

analysis of the airflows around the Orbiter, External Tank, and Solid Rocket 

Boosters, indicated that the foam on a larger area of the ET should be 

reassessed; 

2. Several rudder speed brake actuators were discovered to have been incorrectly 

assembled during the original manufacture over 20 years ago. Further, the gears 

in the actuators have generally suffered minor damage with use and time. 

Therefore, all the actuators are being replaced or refurbished; and 

3. Delays in the design and manufacture of a new camera/laser boom that will be 

used by the Orbiter’s robotic arm to inspect for possible damage while on orbit. 

This change in schedule means that NASA will have additional time to implement the CAIB 

recommendations before return to flight. In many cases this change also allows expected 

plans to be at least partially implemented. For example, the CAIB called for a detailed plan to, 

among other things, establish an Independent Technical Authority. It is expected that plan will 

now be implemented, at least for the Space Operations Mission Directorate [called the Office 

of Space Flight at the time], before next year. 

The expanded period before the next launch also allows NASA additional time to select and 

perfect methods to implement technical solutions, such as inspecting the Orbiter Thermal 

Protection System for damage. Since the loss of Columbia, NASA has been engaged in a 

wide-ranging search for corrective and preventive measures of all types. In some cases, the 

time is approaching when decisions must be made as to the most promising alternatives and 

resources focused on this smaller set of possibilities – the garden must be thinned. In this 

sense, the additional time until launch can be seductive and leadership will need to be 

exercised to sort the many options under consideration. 

The second major change since December is the announcement of President Bush’s vision for 

the future of space exploration, particularly the human space flight component. The President 

proposed to use the Space Shuttle to complete the construction of the International Space 

Station and then retire the Space Shuttle no later than 2010. In its place would be continued 

reliance on international partners to service the International Space Station as well as the 

possibility of private sector development of launch vehicles. During the next decade, NASA 

would also begin to develop the capability to return astronauts to the moon, establish a lunar 

presence, and begin the efforts to explore Mars. 

While the President’s vision has obvious implications for the long-term use of the Space 

Shuttle, its effects on the current efforts have not been fully examined. However, no matter 

how long the Space Shuttle is used, it must first be safely returned to flight. Therefore, except 

for potential competition for human and financial resources, the new program should have 

minimal impact on the actual return to flight activities and the implementation of CAIB 

recommendations. 

Third, the Task Group determined that the contingency of using the International Space 

Station as a safe haven in the event of potentially catastrophic vehicle damage is becoming 

increasingly important in NASA’s decision-making for return to flight. Therefore, the Task 

Group formally notified NASA of its intent to assess the Contingency Shuttle Crew Support 

capability (“raising the bar” action SSP-3 in the NASA Implementation Plan) much as if it 

were a CAIB recommendation. 

The Task Group is encouraged by NASA’s progress since its last plenary in December 2003. 

Throughout the organization, the people of NASA are engaged and dedicated to correcting the 

deficiencies that led to the demise of Columbia. 

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The RTF TG is conditionally closing its assessment of three CAIB recommendations. 

“Closing” an assessment means that NASA provided sufficient information concerning 

the Agency’s implementation of a specific CAIB return-to-flight recommendation; 

“conditionally” means that closing is dependent on the delivery of final documentation. The 

three assessments being conditionally closed with this second interim report are: R3.3-1, 

Reinforced Carbon-Carbon Non-Destructive Inspection; R4.2-3, Closeout Inspection; and 

R6.3-2, National Imagery and Mapping Agency Memorandum of Agreement. The Task 

Group will continue to monitor the implementation of these recommendations, and NASA has 

agreed to notify the Task Group if there is any material change in status. 

There has been progress on virtually all of the 12 remaining return-to-flight recommendations. 

It is anticipated that several more recommendations will be substantially met by the time of 

the next RTF TG plenary in the summer. 

One universal concern of the Task Group is the personnel requirements to meet the CAIB 

recommendations and other return-to-flight activities. The various new organizations, such as 

the NASA Engineering and Safety Center, the Independent Technical Authority, and the 

System Engineering and Integration Office, all require talented staff drawn largely from the 

current NASA and contractor pool. At some point, the ability of the Space Shuttle Program to 

carry out its mission may be hampered by personnel shortages. 

The most important work remains efforts to eliminate critical ascent debris. If it could be 

guaranteed that no critical debris would come from the External Tank, the immediate cause of 

the loss of Columbia would be rectified. But such a guarantee is impossible short of extensive 

flight testing. Analyses and simulation will allow a level of comfort before launch, and 

advances in non-destructive inspection techniques may add to confidence. However, 

statistically significant results verifying ET debris conditions may not be accomplished even 

by the end of the Space Shuttle Program. 

As such, on-orbit inspection and repair remain necessary to reduce the risk to future flights. 

Should one or both of these capabilities not be fully developed by the anticipated date of 

return to flight, the ability for the crew to await a rescue mission at the International Space 

Station will become an important consideration for the next launch. 

A public meeting was held after this plenary and members of the media were briefed during a 

press conference. 

6.5 Summary of July 2004 Plenary 

This plenary was held on July 22, 2004, by teleconference since scheduling issues prevented 

the members from gathering in a common location. Final fact-finding activities were 

conducted via fax, email, and telephone prior to the public meeting. The public meeting was 

primarily to deliberate closing two Task Group assessments: R4.2-5, KSC Foreign Object 

Debris Definition, and R10.3-1, Digitize Closeout Photos. 

NASA had submitted closure packages for these recommendations on June 15 (R10.3-1) and 

July 15 (R4.2-5), and the Task Group evaluated the closure packages and conducted factfinding to verify the status of each recommendation. After deliberating, the Task Group voted 

to conditionally close its assessment of each recommendation pending the delivery of final 

data from NASA. In each case, the Task Group felt the Agency met the intent of the CAIB. 

6.6 Summary of September 2004 Plenary 

This plenary was held September 14-16, 2004, in Houston, Texas. Even before the plenary 

convened, the public meeting scheduled for September 16, 2004, was postponed. Several 

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members of the Task Group lived in the path of Hurricane Ivan and needed to secure their 

property. Nevertheless, available members of the Task Group met to continue their factfinding activities. There were no assessments being considered for closure during the planned 

meeting. 

During fact-finding, Lt. Gen. Stafford reviewed the previous week’s Congressional testimony 

by himself and NASA Administrator Sean O’Keefe. Afterwards, there was a brief discussion 

of the hurricane damage to the Kennedy Space Center and the possible impacts on return-toflight. At this point the Agency was still expecting a March 2005 launch of STS-114, and 

believed that data for most, if not all, of the open assessments would be provided in time for 

the December 2004 plenary. NASA explained that the events for return-to-flight were 

“milestone driven,” not “schedule driven.” 

An apparent change within NASA was discussed, in which the Agency seemed to be choosing 

a “best effort” path instead of the more formal certification process. Several members of the 

Task Group expressed their opinion that NASA should continue the certification process 

instead of reverting to the less rigorous best effort concept. This plenary was where the Space 

Shuttle Program first introduced the “capability over environment” (C/E) concept to the Task 

Group. A long discussion followed about Recommendation R6.4-1, Thermal Protection 

System Inspection and Repair, attempting to better understand the intent of the CAIB. 

Behavioral Science Technology, Inc. (BST) presented a status of its study of the Agency’s 

cultural change initiative. Representatives from BST previewed their conclusions: NASA 

leadership is committed to making changes in the culture; the safety climate remains very 

strong; the process has begun on the harder, longer-term job of changing the culture; and if 

present activities and trends continue, it is likely that NASA will be successful in 

transforming its culture. BST cautioned, however, that while the commitment is strong at the 

Space Flight Leadership Council level, it seems less so at the program management level. 

BST described an important distinction between culture and climate. Culture comprises the 

common values that drive organizational performance; it is deeply embedded and changes 

slowly. Climate is much more transient; it is a reflection of current pressures and interests. 

BST and NASA officials described the initial phases of the NASA initiative to change its 

culture, as well as less-detailed plans for future phases. 

The Space Shuttle Program provided a status of the NASA return-to-flight plans. There were 

assurances that a limited tile repair capability would be certified prior to the launch of 

STS-114, along with a certification of the External Tank, although it was cautioned that some 

uncertainties would remain. It was noted that many certifications were in the yellow (accepted 

risk) category. The program stated that the non-ET debris allowables were zero; in other 

words, other elements were not allowed to generate any debris. The ET was treated 

differently, and there were specific requirements stated for allowable debris. The program 

provided a status on testing various Orbiter components to determine their ability to withstand 

debris impacts. It had already been determined through testing at the Glenn Research Center 

that certain Orbiter windows needed to be replaced with thicker glass. Testing of the tile and 

reinforced carbon-carbon continued. NASA also provided a status report for ground and flight 

cameras and on the proposed reorganization to meet CAIB R9.1-1 and its three subordinate 

recommendations. The Mission Management Team was the subject for a long discussion 

between Task Group members and NASA representatives. After this the program provided an 

update on Contingency Shuttle Crew Support, and answered a myriad of questions from the 

Task Group. 

6.7 Summary of December 2004 Plenary 

This plenary was held December 14-16, 2004, in Huntsville, Alabama. At the public meeting 

following two days of fact-finding, it was determined that NASA has made considerable 

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progress on meeting the CAIB recommendations for return to flight. The panels 

recommended, and the assembled Task Group approved, the complete closure of six 

assessments and the conditional closure of one additional assessment. 

However, considerable work remains. Eight items remain open, including some of the 

toughest technological challenges the recommendations present: shedding of debris, 

strengthening the reinforced carbon-carbon, hardening the Orbiter, and repair of the Thermal 

Protection System. Most of the operational issues have been addressed, with the largest 

remaining concern involving the ability to detect and repair damage to the Space Shuttle 

while on orbit. Some planning remains to be accomplished before the International Space 

Station can potentially be used as a “safe haven” for the crew of a damaged Orbiter while they 

await the launch of a rescue mission. NASA has also made substantial progress on the various 

management issues the CAIB cited as “half” the cause of the demise of Columbia, but 

sufficient detail of plans, exercise of new capabilities and responsibilities, and adequate 

documentation remain open issues. 

Several of the CAIB return-to-flight recommendations involve enhanced imagery of the Space 

Shuttle during ascent and while on orbit. NASA has made sufficient progress on imagery to 

allow the RTF TG to fully or conditionally close three assessments (R3.4-1, R3.4-2, R6.3-2) 

and note substantial progress on a fourth (R3.4-3, which will be formally considered as part of 

R6.4-1, Thermal Protection System Inspection and Repair). 

Taken together, the changes in the capability to observe and examine the Space Shuttle during 

ascent will allow a more complete evaluation of the adequacy of the design and process 

changes made to the External Tank in the reduction of critical debris. The enhanced imagery 

will also contribute to the ability to conduct on-orbit inspections. There will undoubtedly be 

foam shed from the External Tank during the next and subsequent launches. The questions 

will be: how large are the pieces, where on the tank did the shedding occur, and where did the 

debris impact? The ascent imagery will help answer these questions. 

Some months ago, it became clear that the immense amount of new data, much in the form of 

imagery, would require a new approach to integration. In response, NASA formed a 

development team that has produced a Thermal Protection System Operations Integration 

Plan intended to allow the Mission Management Team to make a timely entry readiness, 

The Return to Flight 

Task Group co-chair 

and panel leads brief 

the news media 

following the 

December 16, 2004 

public meeting in 

Huntsville, Alabama. 

From left to right:

 Mr. Joseph W. 

Cuzzupoli, Col. 

James C. Adamson, 

Dr, Dan L. Crippen, 

and Col. Richard O. 

Covey. At the far 

right is the Task 

Group’s Public 

Affairs Officer, Mr. 

David B. Drachlis. 

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repair, or safe haven determination. The latest version of the plan, though still needing further 

simulation and testing, is very robust and a potential model for other integration activities 

within the Space Shuttle Program, as well as the Agency. 

Two assessments affecting closeout procedures (R4.2-3 and R10.3-1) were moved from 

conditionally closed to fully closed at the plenary. “Closeout” refers to the process of 

finalizing work on the vehicle, often in an area that is then sealed from further view or 

inspection. The requirement for two-person closeouts is simply intended to add an additional 

pair of eyes to the evaluation of the completed work before the area is sealed for flight. The 

requirement for digitized closeout photos is intended to yield an adequate ability to both 

examine work after closeouts and the ability to easily recall the images, particularly while the 

Space Shuttle is on-orbit. 

During the course of its investigation, the CAIB uncovered a technical deficiency in the bolt 

catcher, a device that prevents the explosive bolts used to mate the Solid Rocket Boosters to 

the External Tank from becoming debris that might impact the Orbiter. Although determined 

not to have contributed to the Columbia accident, the CAIB correctly wrote a 

recommendation (R4.2-1) requiring NASA to fix the problem. NASA has successfully 

redesigned, tested, and requalified the SRB bolt catcher, and the Task Group closed its 

assessment of this recommendation. 

Although most of the management-related recommendations remain open, NASA has made 

substantial progress since the last plenary. Most notably, the response to Recommendation 

7.5-1 (assessed as part of R9.1-1) to create an Independent Technical Authority (ITA) has 

been formulated, and implementation has begun. The first “warrants,” the official delegation 

of authority to specific individuals, have been issued. 

The role of the Mission Management Team, which received a great deal of attention 

immediately after the Columbia accident, has been clarified and expanded. The new Mission 

Management Team conducted 10 simulations of various aspects of the next mission and plans 

an end-to-end, full-mission simulation beginning in late February and lasting several days. 

The systems engineering and integration function, which the CAIB noted had gradually 

atrophied, has been reinvigorated and has an expansive role in return to flight. However, the 

RTF TG remains concerned that without adequate documentation, the renewed vigor will 

dissipate soon after the launch of STS-114. 

6.8 Summary of February 2005 Plenary 

This plenary was held on February 17, 2005, by teleconference. This public meeting was 

primarily to deliberate closing the Task Group assessment on R3.3-1, Reinforced CarbonCarbon Non-destructive Inspection. The Recommendation had been conditionally closed in 

April 2004, and NASA submitted the requested additional data on February 2, 2005. The Task 

Group had evaluated the revised closure package and conducted fact-finding to verify the 

status of the recommendation. 

A public meeting was held after this plenary and members of the media were briefed during a 

press conference. After deliberating, the Task Group closed its assessment of R3.3-1, feeling 

that NASA had met the intent of the CAIB. 

6.9 Summary of the March 2005 Plenary 

This plenary was held March 28-30, 2005, in Houston, Texas, and was originally intended to 

be the final face-to-face meeting of the Task Group prior to writing the final report. However, 

in the weeks leading up to the meeting, it was apparent that NASA had not made sufficient 

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progress in documenting its compliance with the CAIB return-to-flight recommendations, and 

that it was unlikely all of the closure packages would be delivered to the Task Group in time 

to complete their assessments during the meeting. Therefore, even before the March 2005 

meeting convened, it was expected that another plenary would be needed before the launch of 

STS-114 to evaluate the final closure packages yet to be received from NASA. 

As the program’s schedules for delivering final closure packages to the Task Group continued 

to slip, the RTF TG began to wonder if any assessments could be made at the meeting. When 

the plenary was convened on March 22, 2005, the Task Group’s concerns were realized. 

During two days of fact-finding prior to a scheduled public deliberation scheduled for March 

24, the Task Group decided that insufficient documentation existed for any assessments to be 

made. The public meeting was cancelled. 

6.10 Summary of the Early June 2005 Plenary 

This plenary was held June 6-8, 2005, in Houston, Texas. By this time, NASA had provided 

preliminary or final closure packages for all of the remaining CAIB recommendations. Factfinding was held the afternoon of June 6 and all day June 7, with the Space Shuttle Program 

Manager and various other program officials providing detailed status briefings to the Task 

Group. The Associate Administrator for Space Operations briefed the Task Group on June 7, 

presenting the perspective from NASA Headquarters on the upcoming STS-114 mission and 

the changes being implemented by the new NASA Administrator. 

The public meeting was held the morning of June 8, 2005. The Panel responsible for each 

recommendation provided a status or closure plan to the assembled Task Group, and in the 

end, the Task Group decided that five CAIB recommendations and the “raising the bar” Space 

Shuttle Program action had been completed. One of these, R3.4-1, Ground-Based Imagery, 

had been conditionally accepted during the December 2004 plenary; the Task Group now 

believed that NASA had provided the remaining data in a satisfactory manner and the 

recommendation was accepted to have fully met the intent of the CAIB. Four others: R3.4-3, 

High-Resolution Imagery of Orbiter; R6.2-1, Consistency with Resources; R6.3-1, Mission 

Management Team Improvements; and R9.1-1, Detailed Plan for Organizational Changes, 

were deliberated during the meeting. Task Group members agreed that the changes made by 

NASA for all four recommendations met the intent of the CAIB. 

For the SSP-3, Contingency Shuttle Crew Support raising-the-bar action, the Task Group first 

discussed what criteria to measure against, since this was not a CAIB recommendation. 

Eventually, the Task Group decided that the original criteria defined by the Space Shuttle 

The Return to Flight 

Task Group 

conducts a 

deliberative public 

meeting on June 8, 

2005, in Webster, 

Texas. 

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Final Report of the Return to Flight Task Group 

Program would provide the measure, and it was agreed that the Space Shuttle and ISS 

Programs had both exceeded their initial goals. The Task Group concluded, “NASA set a 

raising the bar goal for itself and exceeded that goal by a significant margin.” 

This left only three recommendations for the Task Group to consider before the return to 

flight: R3.2-1, External Tank Debris Shedding; R3.3-2, Orbiter Hardening; and R6.4-1, 

Thermal Protection System Inspection and Repair. The work on these recommendations is ongoing, with design reviews extended into late June. The Task Group decided to allow NASA 

additional time to complete work on these three recommendations and tentatively set a June 

27 date for the last Task Group plenary. It is expected that NASA will have submitted closure 

packages on these last three CAIB recommendations by the time of the last plenary. 

6.11 Summary of the Late June 2005 Plenary 

As the scheduled launch date of STS-114 approached, the Task Group and NASA attempted 

to come to closure on the final three assessments of the CAIB return-to-flight 

recommendations. These included what many observers considered the most critical 

recommendations: R3.2-1, External Tank Debris Shedding; R3.3-2, Orbiter Hardening; and 

R6.4-1, Thermal Protection System Inspection and Repair. The major delay was that NASA’s 

final debris and design certification reviews were being conducted into late June, and the Task 

Group wanted to review the results of these reviews prior to completing their assessments. 

The final closure packages for R3.2-1 and R3.3-2 were not received by the Task Group until 

during the plenary meeting; R6.4-1 had been received earlier in June. 

A meeting was set between the Task Group leadership and the NASA Administrator for the 

morning of June 28, so the final plenary meeting was scheduled to occur in Washington, D.C., 

on June 27. This would allow the Task Group to work through the evening to ready the 

Executive Summary that would be delivered to the Administrator the following morning. 

Final fact-finding, including a required annual ethics briefing, was conducted during a closed 

meeting on the morning of June 27, with a public meeting held in the afternoon. The public 

meeting location had been changed late the day before because a broken fire sprinkler flooded 

the original location. The new location was approximately two blocks away. 

At the public meeting the Technical Panel recommended closing R3.2-1 and R3.3-2 as having 

met the intent of the CAIB. However, after spirited discussion, the majority of the Task Group 

voted that NASA had not met the intent of the CAIB for R3.2-1, although in both cases the 

Task Group felt that NASA had accomplished some excellent work. The majority of the Task 

Group also voted that NASA had not met the intent of the CAIB for R3.3-2, although again, 

the group felt that excellent work had been accomplished and that extenuating circumstances 

(the mandate to retire the Space Shuttle by 2010) understandably caused NASA to cancel 

some future work. Relative to R6.4-1, despite extensive efforts on the part of the Tile Repair 

Project and RCC Repair Project to develop a practicable TPS repair capability, the majority of 

the Task Group voted that the intent of CAIB Recommendation 6.4-1 had not been met, 

although there was a minority opinion that may be found elsewhere in this report. A press 

conference was held after the public meeting. 

An Executive Summary of this report was finalized in time to deliver it to the NASA 

Administrator on the morning of June 28, and copies were subsequently delivered to Congress 

and the White House. An electronic copy was posted to the Task Group’s website. The 

version contained at the beginning of this report has been slightly edited for readability 

without affecting its content. 

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APPENDIX A – RETURN TO FLIGHT TASK GROUP CHARTER 

The original Task Group charter is shown below. 

Establishment and Authority 

The NASA Administrator, having determined that it is in the public interest in connection 

with performance of the Agency duties under the law, and with the concurrence of the 

General Services Administration, establishes the NASA Return to Flight Task Group, 

pursuant to the Federal Advisory Committee Act (FACA), 5 U.S.C. App. §§1 et seq. 

Purpose and Duties 

1. The Task Group will perform an independent assessment of NASA’s actions to 

implement the recommendations of the Columbia Accident Investigation Board 

(CAIB), as they relate to the safety and operational readiness of STS-114. As 

necessary to its activities, the Task Group will consult with former members of 

the CAIB. 

2. While the Task Group will not attempt to assess the adequacy of the CAIB 

recommendations, it will report on the progress of NASA’s response to meet the 

intent. 

3. The Task Group may make other such observations on safety or operational 

readiness, as it believes appropriate. 

4. The Task Group will draw on the expertise of its members and other sources to 

provide its assessment to the Administrator. The Task Group will hold meetings 

and make site visits as necessary to accomplish its fact-finding. The Task Group 

will be provided information necessary to perform its advisory functions, 

including activities of both the Agency and its contractors. 

5. The Task Group will function solely as an advisory body and will comply fully 

with the provisions of the FACA. 

Organization 

The Task Group is authorized to establish panels in areas related to its work. The panels will 

report findings and recommendations to the Task Group. 

Membership 

In order to reflect a balance of views, the Task Group will consist of non-NASA employees 

and one NASA non-voting, ex officio member, the Deputy Associate Administrator for Safety 

and Mission Assurance. In addition, there may be associate members selected for Task Group 

panels. The Task Group may also request appointment of consultants to support specific tasks. 

members of the Task Group and panels will be chosen from among industry, academia, and 

government with recognized knowledge and expertise in fields relevant to safety and space 

flight. 

The Task Group members and the Co-Chairs of the Task Group will be appointed by the 

Administrator. At the request of the Task Group, associate members and consultants will be 

appointed by the Associate Deputy Administrator (Technical Programs). 

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Final Report of the Return to Flight Task Group 

Administrative Provisions 

1. The Task Group will formally report its results to NASA on a continuing basis 

at appropriate intervals, including a final written report. 

2. The Task Group will meet as often as required to complete its duties and will 

conduct at least two public meetings. Meetings will be open to the public, except 

when the General Counsel and the Agency Committee Management Officer 

determine that the meeting or a portion of it will be closed pursuant to the 

Government in the Sunshine Act or that the meeting is not covered by the 

Federal Advisory Committee Act. Panel meetings will be held as required. 

3. The Executive Secretary will be appointed by the Administrator and will serve 

as the Designated Federal Official. 

4. The Office of Space Flight will provide technical and staff support through the 

Task Force on International Space Station Operational Readiness. The Office of 

Space Flight will provide operating funds for the Task Group and panels. The 

estimated operating costs total approximately $2 million, including 17.5 work 

years for staff support. 

5. Members of the Task Group are entitled to be compensated for their services at 

the rate equivalent to a GS 15, step 10. Members of the Task Group will also be 

allowed per diem and travel expenses as authorized by 5 U.S.C. § 5701 et seq. 

Duration 

The Task Group will terminate 2 years from the date of this charter, unless terminated earlier 

or renewed by the NASA Administrator. 

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Final Report of the Return to Flight Task Group 

Charter Extension 

Because the Task Group did not complete their activities prior to the July 23, 2005, expiration 

of the original charter, an extension was required to complete the final report and prepare data 

for delivery to the National Archives. The revised charter is shown below. 

Establishment and Authority 

The NASA Administrator established the NASA Return to Flight Task Group (“Task 

Group”). Having determined that it is in the public interest in connection with performance of 

Agency duties under the law, and with the concurrence of the General Services 

Administration, the NASA Administrator hereby renews and amends the Task Group’s 

charter, pursuant to the Federal Advisory Committee Act (FACA), 5 U.S.C. App. §§1 et seq. 

Purpose and Duties 

1. The Task Group will perform an independent assessment of NASA’s actions to 

implement the recommendations of the Columbia Accident Investigation Board 

(CAIB), as they relate to the safety and operational readiness of STS-114. As 

necessary to its activities, the Task Group will consult with former members of 

the CAIB. 

2. While the Task Group will not attempt to assess the adequacy of the CAIB 

recommendations, it will report on the progress of NASA’s response to meet the 

intent. 

3. The Task Group may make other such observations on safety or operational 

readiness, as it believes appropriate. 

4. The Task Group will draw on the expertise of its members and other sources to 

provide its assessment to the Administrator. The Task Group will hold meetings 

and make site visits as necessary to accomplish its fact-finding. The Task Group 

will be provided information necessary to perform its advisory functions, 

including activities of both the Agency and its contractors. 

5. The Task Group will function solely as an advisory body and will comply fully 

with the provisions of the FACA. 

Organization 

The Task Group is authorized to establish panels in areas related to its work. The panels will 

report findings and recommendations to the Task Group. 

Membership 

To reflect a balance of views, the Task Group will consist of non-NASA employees and one 

NASA nonvoting, ex officio member, the Deputy Chief Safety and Mission Assurance 

Officer. In addition, there may be associate members selected for Task Group panels. The 

Task Group may also request appointment of consultants to support specific tasks. Members 

of the Task Group and panels will be chosen from among industry, academia, and government 

with recognized knowledge and expertise in fields relevant to safety and space flight. 

The Task Group members and the Co-Chairs of the Task Group will be appointed by the 

Administrator. At the request of the Task Group, associate members and consultants will be 

appointed by the Deputy Chief Engineer/Independent Technical Authority. 

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Final Report of the Return to Flight Task Group 

Administrative Provisions 

1. The Task Group will formally report its results to NASA on a continuing basis 

at appropriate intervals, including a final written report. 

2. The Task Group will meet as often as required to complete its duties and will 

conduct at least two public meetings. Meetings will be open to the public, except 

when the General Counsel and the Agency Committee Management Officer 

determine that the meeting or a portion of it will be closed pursuant to the 

Government in the Sunshine Act or that the meeting is not covered by the 

FACA. Panel meetings will be held as required. 

3. The Executive Secretary will be appointed by the Administrator and will serve 

as the Designated Federal Official. 

4. The Space Operations Mission Directorate will provide technical and staff 

support through the Task Force on International Space Station Operational 

Readiness. The Space Operations Mission Directorate will provide operating 

funds for the Task Group and panels. The estimated operating costs total 

approximately $3.5 million which includes 7 workyears for staff support. 

5. Members of the Task Group are entitled to be compensated for their services at 

the rate equivalent to a GS 15, step 10. Members of the Task Group will also be 

allowed per diem and travel expenses as authorized by 5 U.S.C. § 5701 et seq. 

Duration 

The Task Group shall terminate upon the issuance of its final report unless terminated before 

that date or subsequently renewed by the NASA Administrator. 

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APPENDIX B – RTF TG MEMBERS 

Lieutenant General Thomas P. Stafford, U.S. Air Force (Retired) 

Co-Chair, Return to Flight Task Group 

President, Stafford, Burke & Hecker Inc., technical consulting firm 

A member of NASA’s second astronaut group, Stafford 

was pilot of Gemini 6 and commanded Gemini 9, and 

orbited the moon as Commander of Apollo 10. He was 

the American Commander in the Apollo-Soyuz Test 

Project, the first rendezvous between American and 

Soviet spacecraft. Stafford became head of the 

astronaut group and was later named Deputy Director 

of Flight Crew Operations at the NASA Manned 

Spaceflight Center. He left NASA in 1975 to head the 

Air Force Test Flight Center and in 1978 became 

Deputy Chief of Staff, Research, Development and 

Acquisition, U.S. Air Force Headquarters. A consultant 

since 1980, Stafford is Chairman of the NASA 

Advisory Council Task Force on International Space 

Station Operational Readiness. He served as Defense Adviser to President Ronald Reagan and 

headed The Synthesis Group, which planned for the U.S. return to the moon and eventual 

Mars missions. He was Chairman of the NASA Advisory Council Task Force on Shuttle-Mir 

Rendezvous and Docking Missions. Among his awards, Stafford received the Congressional 

Space Medal of Honor. He served on the National Research Council’s Aeronautics and Space 

Engineering Board, the Committee on NASA Scientific and Technological Program Reviews, 

and the Space Policy Advisory Council. Stafford is an graduate of the U.S. Naval Academy. 

Colonel Richard O. Covey, U.S. Air Force (Retired) 

Co-Chair, Return to Flight Task Group 

President, Boeing Service Company 

Colonel Covey is a veteran of four Space Shuttle 

flights. He was the pilot of Discovery on the first 

return-to-flight mission following the Challenger 

accident, and he was commander of Endeavour on the 

first mission to service and repair the Hubble Space 

Telescope. He also held management positions in the 

Astronaut Office and Flight Crew Operations 

Directorate. As a fighter pilot, Covey flew 339 combat 

missions in Southeast Asia. He was an F-4 and A-7D 

weapons systems test pilot and Joint Test Force 

Director for electronic warfare testing of the F-15. 

Covey’s organization at Boeing supports commercial 

and U.S. government space and communication 

programs. Earlier, he was Vice President of Boeing’s 

Houston operations. Covey has received 27 Defense Department and Air Force medals, plus 

the National Intelligence Medal of Achievement. NASA awarded him the Distinguished 

Service Medal, the Outstanding Leadership Medal, and the Exceptional Service Medal. For 

his role on the Hubble servicing mission, Covey and his crew received both the Goddard 

Trophy and the Collier Trophy. He holds a B.S. in Engineering Sciences from the U.S. Air 

Force Academy and an M.S. in Aeronautics and Astronautics from Purdue University, and 

was named the Outstanding Graduate of his class at the Air Force Test Pilot School. 

Page 153 of 216 
Final Report of the Return to Flight Task Group 

Colonel James C. Adamson, U.S. Army (Retired) 

CEO, Monarch Precision, LLC 

Colonel Adamson, a former astronaut, earned his B.S. 

in Engineering from the U.S. Military Academy at West 

Point and his M.S. in Aerospace Engineering from 

Princeton University. He returned to West Point as an 

Assistant Professor of Aerodynamics, after which he 

was selected to attend the Navy Test Pilot School. In 

1981 he became Aerodynamics Officer for the Space 

Shuttle Operational Flight Test Program. Adamson 

became an astronaut in 1984 and flew two missions, 

one aboard Columbia and the other on Atlantis. After 

retiring from NASA, Adamson established his own 

consulting firm, Monarch Precision, and then became 

President/CEO of Lockheed Engineering and Sciences 

Company. In 1995 he helped create United Space 

Alliance and became the company’s first Chief 

Operating Officer. Adamson was then recruited to serve as President/CEO of Allied Signal 

Technical Services Corporation, which later became Honeywell Technology Solutions, Inc. 

Retiring from Honeywell in 2001; Adamson resumed part-time consulting with Monarch 

Precision. In addition to corporate board positions, he has served as a member of the NASA 

Advisory Council Task Force on Shuttle-Mir Rendezvous and Docking Missions and is 

currently a member of the NASA Advisory Council Task Force on International Space Station 

Operational Readiness. 

Major General William A. Anders, U.S. Air Force Reserve (Retired) 

Major General Anders was selected for the astronaut 

corps in 1963. He was the Lunar Module Pilot of 

Apollo 8 and backup Command Module Pilot for 

Apollo 11. Anders subsequently received Presidential 

appointments to the National Aeronautics and Space 

Council, the Atomic Energy Commission and the 

Nuclear Regulatory Commission (where he was the 

first Chairman), and he served as U.S. Ambassador to 

Norway. Anders held executive positions at a number 

of corporations, including General Electric, Textron and 

General Dynamics, where he was Chairman and CEO. 

While in that position, he was awarded the National 

Security Industrial Association’s “CEO of the Year” 

award. Anders established several world flight records 

and has received numerous awards, including Distinguished Service Medals from the Air 

Force, NASA and the Atomic Energy Commission. He is a member of the National Academy 

of Engineering, the Society of Experimental Test Pilots and the Experimental Aircraft 

Association. He is also the founder and President of the Heritage Flight Museum. Anders 

received his B.S. in Electrical Engineering from the United States Naval Academy and earned 

his pilot’s wings in 1956. He received his M.S. in Nuclear Engineering from the U.S. Air 

Force Institute of Technology, graduating with honors. 

Page 154 of 216 
Final Report of the Return to Flight Task Group 

Dr. Walter D. Broadnax, Ph.D 

President, Clark Atlanta University 

Prior to his current position, Dr. Broadnax was Dean of 

the School of Public Affairs, American University, and 

Professor of Public Policy and Management at the 

University of Maryland, where he directed the Bureau 

of Governmental Research. Broadnax also served as: 

Deputy Secretary and Chief Operating Officer, U.S. 

Department of Health and Human Services; President, 

Center for Governmental Research; President, New 

York State Civil Service Commission; Lecturer and 

Director, Kennedy School of Government, Harvard 

University; Senior Staff Member, Brookings Institution; 

Principal Deputy Assistant Secretary for Planning and 

Evaluation, U.S. Department of Health, Education and 

Welfare; Director, Children, Youth and Adult Services, 

State of Kansas; and Professor, Federal Executive Institute. Broadnax has held leadership 

positions in professional associations such as: the American Political Science Association, the 

Association of Public Policy and Management and the American Society for Public 

Administration. Broadnax received his Ph.D. from the Maxwell School at Syracuse 

University, his B.A. from Washburn University and his M.P.A from the University of Kansas. 

He has served as President, American Society for Public Administration, Fellow, National 

Academy of Public Administration and Trustee of the Academy’s Board. He is a member of 

the Syracuse University Board of Trustees, Harvard University’s Taubman Center Advisory 

Board and the United States Comptroller General Advisory Board. 

Dr. Kathryn I. Clark, Ph.D. 

President, Docere (consulting firm specializing in science and education) 

Dr. Clark served as NASA’s Chief Scientist for the 

International Space Station Program and as Chief 

Scientist for the Human Exploration and Development 

of Space Enterprise. Her particular interest is in human 

factors, the elements necessary for the health, safety 

and efficiency of crews in long-duration space flight. 

Clark served as Deputy Director of the Center for 

Microgravity Automation Technology, one of the 

NASA Commercial Space Centers. Clark’s NASA 

experience began with a neuromuscular development 

study that flew on Atlantis in 1994. These experiments 

were repeated and augmented on Discovery in 1995. 

She was also involved in the Neurolab project flown on 

Columbia in 1998 and a student-designed ladybug 

experiment that flew on Columbia in 1999. Clark is the recipient of the NASA Goddard Space 

Flight Center Customer Service Excellence Award. Clark received both her M.S. and Ph.D. from 

the University of Michigan and then joined the university faculty in the Department of Cell 

and Developmental Biology in 1993. Clark chairs the Academic Affairs Committee, Board of 

Control, Michigan Technological University. She also serves on the Board of Trustees of the 

Western Reserve Academy and the Board of Advisors of the Jean Michel Cousteau Society. 

She serves on the boards of the Space Day Foundation and Orion’s Quest, both educationoriented not-for-profit organizations. Clark is also a member of the NASA Advisory Council 

Task Force on International Space Station Operational Readiness. 

Page 155 of 216 
Final Report of the Return to Flight Task Group 

Mr. Benjamin A. Cosgrove 

Consultant 

In the course of a 44-year career with the Boeing 

Company, Mr. Cosgrove was an engineer and manager 

associated with most of the company’s jet aircraft 

programs. He served as stress engineer or structural unit 

chief on the B-47, B-52, and KC-135, and on the Boeing 

707, 727, 737, and 747 jetliners. He was Chief Engineer 

of the 767. Cosgrove was honored by Aviation Week & 

Space Technology for his role in converting the Boeing 

767 transport design from a three-member to two-member 

cockpit configuration, and he received the Ed Wells 

Technical Management Award for his work addressing 

issues of aging aircraft. Cosgrove received the National 

Aeronautics Association’s Wright Brothers Memorial 

Trophy for his lifetime contributions to commercial 

aviation safety and for technical achievement. He is a member of the National Academy of 

Engineering and a fellow of both the American Institute of Aeronautics and Astronautics and 

the Royal Aeronautical Society. After retiring in 1993 as Senior Vice President, Boeing 

Commercial Airplane Group, Cosgrove became a consultant. Cosgrove was elected to the 

National Academy of Engineering in 1992. He holds both a B.S. in Aeronautical Engineering 

and an honorary Doctorate of Engineering from the University of Notre Dame. Cosgrove has 

served on the NASA Advisory Committee’s Task Force on International Space Station 

Operational Readiness and the Committee on Space Shuttle Upgrades. 

Dr. Dan L. Crippen, Ph.D. 

Former Director, Congressional Budget Office 

Dr. Crippen served as the fifth Director of the 

Congressional Budget Office. His public service 

positions have also included: Chief Counsel and 

Economic Policy Adviser to the Senate Majority Leader 

(1981-1985); Deputy Assistant to the President for 

Domestic Policy (1987-1988); and Domestic Policy 

Advisor and Assistant to the President for Domestic 

Policy (1988-1989) – a position in which he advised the 

President on all issues relating to domestic policy, 

including the preparation and presentation of the federal 

budget. He has served on several national commissions, 

including the National Commission on Financial 

Institution Reform, Recovery, and Enforcement. He 

currently serves on the Aerospace Safety Advisory 

Panel. Crippen has substantial experience in the private sector as well. Before joining the 

CBO, he was a principal with Washington Counsel, a law and consulting firm. He has also 

served as Executive Director of the Merrill Lynch International Advisory Council and as a 

founding partner and Senior Vice President of The Duberstein Group, an independent 

strategic planning and consulting firm. Crippen received a B.A. from the University of South 

Dakota in 1974, an M.A. from Ohio State University in 1976, and a Ph.D. in Public Finance 

from Ohio State in 1981. 

Page 156 of 216 
Final Report of the Return to Flight Task Group 

Mr. Joseph W. Cuzzupoli 

Vice President and K-1 Program Manager, Kistler Aerospace Corporation 

Mr. Cuzzupoli has more than 40 years of experience in 

aerospace engineering and management. He began his 

career with General Dynamics as Launch Director 

(1959-1962), and then became Manager of 

Manufacturing/Engineering and Director of Test 

Operations for Rockwell International (1962-1966). As 

Rockwell’s Assistant Program Manager for Apollo, 

Cuzzupoli managed the building and testing of Apollo 

6, Apollo 8, Apollo 9, and Apollo 12. He later became 

Rockwell’s Vice President of Operations and then Vice 

President and Program Manager for the Space Shuttle 

Orbiter Project. Cuzzupoli left Rockwell in 1980 and 

consulted on various aerospace projects for NASA 

centers until 1991 when he joined American Pacific 

Corporation as Senior Vice President. In his current position at Kistler Aerospace, he has 

primary responsibility for design and production of the K-1 reusable launch vehicle. 

Cuzzupoli holds a B.S. in Mechanical Engineering from the Maine Maritime Academy, a B.S. 

in Electrical Engineering from the University of Connecticut and a Certificate of 

Management/Business Administration from the University of Southern California. He was a 

member of the NASA Advisory Council’s Task Force on Shuttle-Mir Rendezvous and 

Docking Missions and is a current member of the Council’s Task Force on International 

Space Station Operational Readiness. 

Dr. Charles C. Daniel, Ph.D. 

Engineering Consultant 

From Saturn V to the International Space Station (ISS), 

Dr. Daniel has served as an engineer and manager in 

space flight vehicle design, analysis, integration and 

testing. His career began in 1968 at the Marshall Space 

Flight Center (MSFC) where he supported Saturn 

Instrument Unit operations for Apollo 11, 12 and 13. 

He performed avionics integration work for the Skylab 

program. For the Space Shuttle’s Solid Rocket Boosters 

(SRB), he developed avionics and served as Flight 

Operations Lead. Daniel worked with the original 

Space Station Skunk Works for definition of the space 

station concept and developed the project’s master 

engineering schedule. Following the Challenger 

accident, he led the evaluation of all Space Shuttle 

hazard analyses and coordinated acceptance analyses associated with modifications to the 

SRBs. During Space Station Freedom development, he was the Avionics Lead and served as 

MSFC Lead for Level II assembly and configuration development. Daniel helped plan 

Russian participation in the Space Station Restructure activity and later returned to MSFC as 

Chief Engineer for Space Station. Daniel holds a Ph.D. in Engineering and has completed 

postgraduate work at the University of California, Berkeley and MIT. He has served on one 

NASA Advisory Council task force on Shuttle-Mir Rendezvous and Docking Operations and 

another on ISS Operational Readiness. 

Page 157 of 216 
Final Report of the Return to Flight Task Group 

Dr. Amy K. Donahue, Ph.D. 

Assistant Professor of Public Policy, the University of Connecticut 

Dr. Donahue teaches in the Master of Public 

Administration and Master of Survey Research 

programs. Her research focuses on productivity of 

emergency services organizations and on the nature of 

citizen demand for public safety services. Her published 

work deals with the design, management and finance of 

fire departments and other public agencies. Donahue 

has served as technical adviser to the Department of 

Homeland Security’s Science and Technology 

Directorate, helping to develop programs for 

emergency responders. As Senior Adviser to the NASA 

Administrator from 2002 to 2004, Donahue sought 

opportunities within NASA to contribute to homeland 

security efforts government-wide. Donahue has 20 

years of field experience and training in an array of 

emergency services-related fields, including managing a 911 communications center, and 

working as a firefighter and emergency medical technician in Fairbanks, Alaska and upstate 

New York. In addition, she has served as an officer in the U.S. Army’s Medical Service 

Corps. In 2003, Donahue spent three months in the field in Texas managing the Columbia 

debris recovery operation. Donahue currently serves on the Aerospace Safety Advisory Panel 

(ASAP). Donahue received her B.A. in Geological and Geophysical Sciences from Princeton 

University and both her Ph.D. in Public Administration and her M.P.A. from the Maxwell 

School of Citizenship and Public Affairs, Syracuse University. Donahue currently serves on 

the Aerospace Safety Advisory Panel (ASAP). 

General Ronald R. Fogleman, U.S. Air Force (Retired) 

President and Chief Operating Officer, Durango Aerospace Inc. 

General Fogleman has experience in air and space 

operations, expertise in long-range programming and 

strategic planning and extensive training in fighter and 

mobility aircraft. He served in the Air Force for 34 

years, culminating in his appointment as Chief of Staff, 

after which he retired in 1997. Fogleman has served as 

a military adviser to the Secretary of Defense, the 

National Security Council and the President of the 

United States. Among other advisory boards, he is a 

member of the National Defense Policy Board, the 

NASA Advisory Council, the Jet Propulsion Laboratory 

Advisory Board, the Council on Foreign Relations, and 

the congressionally directed Commission to Assess 

United States National Security Space Management and 

Organization. He chaired the National Research Council Committee on Aeronautics Research 

and Technology for Vision 2050. Fogleman received an M.A. in Political Science from Duke 

University, graduated from the Army War College, and earned an M.A. in Military History 

from the U.S. Air Force Academy. His military decorations include: Defense Distinguished 

Service Medal with two oak leaf clusters; the Air Force Distinguished Service Medal with oak 

leaf cluster; both the Army and Navy Distinguished Service Medals; Silver Star; Purple Heart; 

Meritorious Service Medal; and two Distinguished Flying Crosses. 

Page 158 of 216 
Final Report of the Return to Flight Task Group 

Ms. Christine H. Fox 

President, Center for Naval Analyses 

A President of the CNA, a federally-funded research 

and development center, Ms. Fox is responsible for 

providing the Department of the Navy and Department 

of Defense with high-quality, independent analysis of 

key issues regarding manning, training, acquisition, and 

operations. Before becoming President, Fox was the 

Vice President and Director of the Center’s Operations 

Evaluation Group. With approximately 45 field 

representatives and 45 Washington-based analysts, this 

group’s analytical purpose is to help operational 

commanders execute their missions. Fox joined the 

CNA in 1981 and since then has served in a variety of 

analysis, leadership and management positions. These 

positions include: Team Leader, Operational Policy 

Team; Director, Anti-Air Warfare Department; Program Director, Fleet Tactics and 

Capabilities; Team Leader of Third Fleet Tactical Analysis Team; Field Representative to 

Tactical Training Group – Pacific; Project Director, Electronic Warfare Project; Field 

Representative to Fighter Airborne Early Warning Wing – U.S. Pacific Fleet; and Analyst, 

Air Warfare Division, Operations Evaluation Group. Fox received her B.S. in mathematics 

and her M.S. in applied mathematics from George Mason University. 

Colonel Gary S. Geyer, U.S. Air Force (Retired) 

Consultant 

Colonel Geyer has 39 years of experience in space 

engineering and program management. In senior 

positions in both government and industry, he has been 

responsible for all aspects of system success, including 

schedule, cost and technical performance. He served for 

26 years with the National Reconnaissance Office 

(NRO) and was the NRO System Program Office 

Director for two major programs, responsible for 

design, manufacture, test, launch and operation of 

several of the most important U.S. reconnaissance 

satellites. Geyer was one of 46 “Pioneers of National 

Reconnaissance” honored by the NRO in 2000 for their 

“significant and lasting contributions to the discipline 

of national reconnaissance,” which contributed to the end of the Cold War. Following his 

NRO service, Geyer was Vice President for a major classified program at Lockheed Martin, 

where he was responsible for all aspects of program and mission success. Geyer teaches 

courses in space design and system engineering/ program management at New Mexico State 

University. He has a B.S. in Electrical Engineering from Ohio State University, an M.S. in 

Electrical Engineering, and M.S. in Aeronautical Engineering from the University of Southern 

California. 

Page 159 of 216 
Final Report of the Return to Flight Task Group 

Brigadier General (Select) Susan J. Helms, U.S. Air Force 

Deputy Director, Operations for Technical Training, Headquarters Air Education and 

Training Command 

Before her current assignment, Colonel Helms was 

Vice Commander of the 45th Space Wing where she 

oversaw military space launches from Cape Canaveral 

Air Force Station (CCAFS) and Eastern Range support 

for commercial, NASA and military space launches 

from CCAFS and Kennedy Space Center, along with 

ballistic missile tests at sea. Selected for the astronaut 

program in 1990, she flew on five Space Shuttle flights 

and served aboard the International Space Station as 

member of the Expedition 2 crew. She logged 211 days 

in space, including a world-record extravehicular 

activity of 8 hours, 56 minutes. After receiving a B.S. in 

Aeronautical Engineering from the U.S. Air Force 

Academy and her commission, Helms was assigned to the Air Force Armament Laboratory as 

F-16 Weapons Separation Engineer, and then became Lead Engineer, F-15 weapons 

separation. In 1985 she received her M.S. in Aeronautics/Astronautics from Stanford 

University and returned to the Air Force Academy as Assistant Professor of Aeronautics. 

After attending the Air Force Test Pilot School in 1988, Helms was assigned as Exchange 

Officer to Canada's Aerospace Engineering Test Establishment, where she worked as Flight 

Test Engineer and Project Officer on the CF-18. She was managing development of a CF-18 

flight control system simulation when selected by NASA. Helms returned to the Air Force in 

2002 to direct the Space Superiority Division, Space Command Requirements Directorate. 

Mr. Richard H. Kohrs 

Chief Engineer, Kistler Aerospace Corporation 

Mr. Kohrs has over 40 years of experience in aerospace 

systems engineering, stress analysis and integration. He 

has held senior management positions in NASA 

programs from Apollo to Space Station. After Apollo, 

Kohrs’s positions in the Space Shuttle Program 

included Manager of System Integration, Deputy 

Manager and then Deputy Director. As Deputy 

Director, he was responsible for the daily engineering, 

processing and operations activities of the Shuttle 

Program, and he developed an extensive background in 

Shuttle systems integration. In 1989, Kohrs became 

Director of Space Station Freedom, with overall 

responsibility for its development and operation. After 

years of public service, he left NASA to become 

Director of the ANSER Center for International Aerospace Cooperation (1994-1997). Kohrs 

joined Kistler Aerospace in 1997. His primary responsibilities as Chief Engineer include 

vehicle integration, design specifications, design data books, interface control, vehicle weight, 

performance and engineering review board matters. In 1956, he received a B.S. from 

Washington University in St. Louis. 

Page 160 of 216 
Final Report of the Return to Flight Task Group 

Ms. Susan Morrisey Livingstone 

Policy and Management Consultant 

From 2001 to 2003, Ms. Livingstone served as Under 

Secretary of the Navy. Her broad executive 

management portfolio comprised planning, budget and 

other functions, but she also focused on programs such 

as space, information technology, and criminal 

investigation. Currently, she serves on the Maxwell 

School’s National Security Studies Board of Advisers 

and the Secretary of the Navy’s Subcommittee on 

Naval History. Livingstone was CEO of the Association 

of the United States Army and Deputy Chairman of its 

Council of Trustees. She was a consultant to the 

Defense Science Board. At American Red Cross 

headquarters, her executive positions included Vice 

President, Health and Safety Services. Livingstone was 

Assistant Secretary of the Army for Installations, Logistics and Environment (1989-1993). 

Among several posts at the former Veterans Administration, Livingstone was Associate 

Deputy Administrator for Logistics. She worked on personal staffs of a Senator and two 

Congressmen. Livingstone received the Secretary of Defense Award for Outstanding Public 

Service and the highest civilian awards from the National Reconnaissance Office, the VA, and 

the Army and Navy Departments. Livingstone received her B.A. from the College of William 

and Mary (1968) and her M.A. in Political Science from the University of Montana (1972), 

and post graduate work at the Fletcher School of Law and Diplomacy. 

Mr. James D. Lloyd, ex-officio 

Deputy Chief Safety and Mission Assurance Officer, NASA 

Mr. Lloyd has extensive experience in safety 

engineering and risk management and has supported a 

number of blue ribbon panels addressing safety 

problems. Beginning in 1969 as a safety engineering 

intern trainee and later as a journeyman system safety 

engineer with the U. S. Army Aviation Systems 

Command, he honed his skills with Army aircraft 

development programs. He was later appointed as 

Chief, Program Evaluation Division in the Army 

Material Command (AMC) Safety Office in Virginia. 

In 1979, he was again reassigned as Director, AMC 

Field Safety Activity in Indiana, where he managed 

safety engineering, evaluation and training support for 

the command's military-industrial operations located world-wide. After the Space Shuttle 

Challenger disaster in 1986, Lloyd joined NASA to help the Agency rebuild its SMA 

program. He was instrumental in fulfilling several of the recommendations from the Rogers 

Commission investigation report. Immediately after Space Shuttle flights resumed, Lloyd 

moved to the Space Station Freedom Program Office in Virginia, where he served in various 

roles culminating in Product Assurance Manager for the program. In 1993 he became 

Director, Safety and Risk Management Division, Office of Safety and Mission Assurance, 

serving as NASA’s “Safety Director.” He assumed his present position as Deputy Chief of 

the same office in 2003. Lloyd also serves as ex-officio member for the NASA 

Advisory Council’s standing Task Force on International Space Station Operational 

Readiness. Lloyd holds a B.S. with honors in Mechanical Engineering from Union College, 

Schenectady, and an M.S. in Industrial Engineering, Texas A&M University. 

Page 161 of 216 
Final Report of the Return to Flight Task Group 

Lieutenant General Forrest S. McCartney, U.S. Air Force (Retired) 

Consultant 

Lt. General McCartney was Commander of the 

Ballistic Missile Organization (responsible for 

development of the Minuteman and Peacekeeper 

ICBMs), Commander of the Air Force Space Division 

and Vice Commander, Air Force Space Command. He 

directed several major satellite programs. He received 

the Distinguished Service Medal, Legion of Merit with 

one oak leaf cluster, Meritorious Service Medal and Air 

Force Commendation Medal with three oak leaf 

clusters, as well as the General Thomas D. White Space 

Trophy and the Military Astronautical Trophy. 

Following the Challenger accident, McCartney was 

assigned to NASA and served as Director of the 

Kennedy Space Center until 1992. His numerous 

awards include NASA’s Distinguished Service Medal, the Presidential Rank Award, the 

National Space Club Goddard Memorial Trophy and the AIAA Von Braun Award for 

Excellence in Space Program Management. After 40 years of military and civil service, 

McCartney became an industry consultant, specializing in evaluation of hardware failure and 

flight readiness. At Lockheed Martin, from 1994 to 2001, he was Astronautics Vice President 

for Launch Operations. McCartney was Vice Chairman of the NASA Aerospace Safety 

Advisory Panel. He has a B.S. in Electrical Engineering from Auburn University, an M.S. in 

Nuclear Engineering from the Air Force Institute of Technology and an honorary doctorate 

from the Florida Institute of Technology. 

Dr. Rosemary O’Leary, Ph.D 

Distinguished Professor of Public Administration and Political Science, Syracuse University 

As the Co-Director of the Program for the Analysis and 

Resolution of Conflict at the Maxwell School of 

Syracuse University, O’Leary also coordinates the 

Ph.D. program in public administration. A member of 

the NASA Aerospace Safety Advisory Panel and the 

National Academy of Public Administration, she was a 

Senior Fulbright Scholar in Malaysia and the 

Philippines. Previously, O’Leary was Professor of 

Public and Environmental Affairs at Indiana University 

and Co-Founder and Co-Director of the Indiana 

Conflict Resolution Institute. She served as Director of 

Policy and Planning for the Kansas Department of 

Health and Environment and has worked as an 

environmental attorney. O’Leary is the author or editor 

of seven books and more than 90 articles and has won 

nine national research awards. She was awarded the Syracuse University Chancellor’s 

Citation for Exceptional Academic Achievement, the highest research award at the university, 

and she has won eight teaching awards. She received the Distinguished Service Award of the 

American Society for Public Administration. O’Leary was Chair of the Public Administration 

Section, American Political Science Association, and the Section on Environment and Natural 

Resources Administration, American Society for Public Administration. O’Leary has a Ph.D. 

in Public Administration from The Maxwell School of Syracuse University, and a J.D., 

M.P.A., and B.S from the University of Kansas. 

Page 162 of 216 
Final Report of the Return to Flight Task Group 

Dr. Decatur B. Rogers, Ph.D. 

Dean, College of Engineering, Technology and Computer Science, Tennessee State University 

Dr. Rogers has held the post of Dean since 1988, and he 

is also Professor of Mechanical Engineering. Before 

joining the faculty of Tennessee State University in 

Nashville, he was Professor and Dean at: Florida State 

University, Tallahassee; Prairie View A&M University, 

Prairie View, Texas; and Federal City College, 

Washington, D.C. At Tennessee State, Rogers has 

fostered a number of collaborations with fellow 

universities and other partners, such as NASA, Boeing, 

General Motors and the Office of Naval Research. One 

of these collaborations is the Strategic Manpower 

Development Project, which aims to increase the 

number of African Americans pursuing doctorates in 

the fields of engineering, technology and computer 

science. Rogers’s areas of expertise include: mechanical and thermal engineering; heating, 

ventilation and air conditioning; two-phase flow; heat transport systems; and engineering 

management. Examples of his publication titles include: Thermodynamics of Fiber-Power 

Insulation; The Engineering Pipeline: A Long-Term Talent Development Strategy for 

Minorities on the Recruitment and Retention of Minorities and Women in Engineering and 

Preparing Black Children to Become Engineers. Rogers holds a Ph.D. in Mechanical 

Engineering from Vanderbilt University, an M.S. in Engineering Management and another in 

Mechanical Engineering from Vanderbilt University and a B.S. in Mechanical Engineering 

from Tennessee State University. 

Mr. Seymour Z. Rubenstein 

Aerospace Consultant and Former President of the Rockwell International Space Systems 

Division 

Mr. Rubenstein has been a leader in commercial and 

government projects for more than 35 years. He served 

as President of the Rockwell International Space 

Systems Division and was a major contributor to the 

design, development and operation of the Space 

Shuttle. At Rockwell, the prime contractor for the 

Space Shuttle, he was the Director of Avionics System 

Engineering during the early development of the 

spacecraft. Subsequently he was promoted to Vice 

President of Engineering and Chief Engineer for Space 

Shuttle Development, followed in 1979 by Vice 

President and Program Manager. He then advanced to 

the position of President of the Rockwell Space Station 

Division before becoming the Space Division President. After his tenure at Rockwell, 

Rubenstein held several positions at McDonnell Douglas. For his contributions to manned 

space exploration and in recognition of his skills as an innovator and problem solver, 

Rubenstein has received the NASA Public Service Medal, the NASA Medal for Exceptional 

Engineering and the Space Systems Award of the American Institute of Aeronautics and 

Astronautics. He is a Fellow of both the AIAA and the American Astronautical Society. Mr. 

Rubenstein holds an MBA from California State University, an MEE from New York 

University, a B.S. in Electrical Engineering from MIT, and a certificate of completion from 

the Stanford Executive Program. 

Page 163 of 216 
Final Report of the Return to Flight Task Group 

Mr. Robert B. Sieck 

Aerospace Consultant 

Mr. Sieck, former Director of Shuttle Processing at the 

Kennedy Space Center (KSC), has an extensive 

background in Space Shuttle systems, testing, launch, 

landing and processing. After serving in the Air Force 

involved with the activation of Titan II missiles, joined 

NASA in 1964 as Gemini Spacecraft Systems Engineer 

and served as Apollo Spacecraft Test Team Project 

Engineer. He became Shuttle Orbiter Test Team Project 

Engineer and was named Engineering Manager for the 

Shuttle Approach and Landing Tests at Dryden Flight 

Research Facility. Sieck was the Chief Shuttle Project 

Engineer for missions STS-1 through STS-7 and 

became the first KSC Shuttle Flow Director in 1983. He 

was appointed Director, Launch and Landing 

Operations, in 1984, serving as Shuttle Launch Director in 1984 and 1985. After the 

Challenger accident in 1986 he was again appointed Launch Director, and also Deputy 

Director, Shuttle Operations (1992-1995). He was Launch Director for the return-to-flight of 

STS-26R and all subsequent Shuttle missions through STS-63. He was appointed Director of 

Shuttle Processing in 1995. After his retirement from NASA, Sieck served with the NASA 

Aerospace Safety Advisory Panel. He earned his B.S. in Electrical Engineering, University of 

Virginia, in 1960 and had post graduate work at Texas A&M and the Florida Institute of 

Technology. 

Mr. Thomas N. Tate 

Consultant 

Mr. Tate was Vice President of Legislative Affairs for 

the Aerospace Industries Association for 17 years. 

Before joining AIA in 1987, he served on the staff of 

the House Committee on Science and Technology in 

positions that included Counsel and Special Assistant to 

the Chairman. He also served with the House 

Subcommittee on Space Science and Applications and 

the House Subcommittee on Energy Research and 

Development. At the Space Division of Rockwell 

International, 1962-1973, Tate worked in engineering 

and marketing on programs such as the Gemini 

Paraglider, Apollo, Apollo/Soyuz, and the Space 

Shuttle. He eventually became Director of Space 

Operations. Earlier, he worked for RCA’s Missile and 

Surface Radar Division (1958-1962), and he served in the U.S. Army as Artillery and Guided 

Missile Officer. Tate received a B.S. from the University of Scranton, 1956. With his 1970 

J.D. from Western State University College of Law, he was named that year’s most 

outstanding student. In 1991, he received the University of Scranton’s Frank J. O’Hara Award 

for Distinguished Alumni in Science and Technology. Tate is adviser to the National Space 

Institute and member of aerospace and defense associations such as AIAA and the National 

Space Club. For 15 years, Tate served on the NASA Senior Executive Service Salary and 

Performance Review Board. 

Page 164 of 216 
Final Report of the Return to Flight Task Group 

Dr. Kathryn C. Thornton, Ph.D. 

Professor, School of Engineering & Applied Science, University of Virginia 

Dr. Thornton teaches in the Department of Science, 

Technology and Society and in the Department of 

Mechanical and Aerospace Engineering. She also 

manages the Graduate Studies Office as Associate Dean 

for Graduate Programs. Selected as an astronaut in 

1984, Thornton is a veteran of four Space Shuttle 

flights between 1989 and 1995, including the maiden 

flight of Endeavour in 1992 and the first Hubble Space 

Telescope Service Mission in 1993. She was Payload 

Commander in 1995 on the second U.S. Microgravity 

Laboratory mission. She has logged over 975 hours in 

space, including more than 21 hours of extravehicular 

activity. Her technical assignments at NASA included 

flight software verification in the Shuttle Avionics 

Integration Laboratory (SAIL). She was a member of the Vehicle Integration Test Team at the 

Kennedy Space Center, and she served as a Spacecraft Communicator, or CAPCOM. 

Thornton holds a B.S. in Physics from Auburn University and an M.S. and Ph.D. in Physics 

from the University of Virginia. She was awarded a NATO Postdoctoral Fellowship to 

continue her research at the Max Planck Institute for Nuclear Physics in Heidelberg, West 

Germany. She was then employed as a physicist at the U.S. Army Foreign Science and 

Technology Center in Charlottesville, Virginia. 

Mr. William Wegner 

Consultant 

Mr. Wegner graduated from the U.S. Naval Academy 

in 1948. He then received M.S. degrees in Naval 

Architecture and Marine Engineering from Webb Institute 

in New York. In 1956, Admiral Hyman Rickover selected 

Wegner to join the Navy’s nuclear program, and he was 

sent to MIT, where he received his M.S. in Nuclear 

Engineering. After a number of field positions, including 

Nuclear Power Superintendent at the Puget Sound Naval 

Shipyard, Wegner served for 16 years as Deputy Director 

to Admiral Rickover in the Naval Nuclear Program. He 

received Distinguished Service Awards from both the 

Defense Department and the Atomic Energy Commission. 

In 1979, Wegner retired from government service and 

formed Basic Energy Technology Associates with three fellow naval retirees. During its 10 

years of successful operation, the firm provided technical services to over 25 nuclear utilities 

and other nuclear-related activities. Wegner has served on a number of panels, including one 

of the National Academy of Sciences that studied the safety of Department of Energy nuclear 

reactors. From 1989 to 1992, he provided technical assistance to the Secretary of Energy on 

nuclear matters. He has supplied technical services to over 50 nuclear facilities. Wegner 

served on the Detroit Edison Board of Directors, 1990-1999. 

Page 165 of 216 
Final Report of the Return to Flight Task Group 

Mr. Vincent D. Watkins 

Executive Secretary, Return to Flight Task Group 

Mr. Watkins has devoted his entire career, now 25 years, to the U.S. space program. Prior to 

his current position, he was Assistant Chief of the Flight Equipment Division in the Johnson 

Space Center’s Safety and Mission Assurance Directorate. He managed assurance activities 

related to the definition, design, development and operation of government-furnished 

equipment (GFE) and extravehicular activity equipment. These engineering functions 

included flight readiness verification, risk assessments, hazard analysis, nonconformance 

tracking and product delivery. In 2003 Watkins served as Executive Officer to the Chief of 

Staff at NASA Headquarters. During this assignment in the Office of the Administrator, he 

was instrumental in developing and implementing several key initiatives, including the 

Columbia Families First Team and the Columbia Accident Rapid Reaction Team. Watkins 

joined NASA in 1980 as Control System Engineer on the Shuttle Training Aircraft. From 

1997 to 2003, he served as Chief of the Flight Equipment Division’s GFE Assurance Branch. 

At UCLA in 2003, he completed a NASA Fellowship on Creativity and Innovation in the 

Organization. He was an inaugural member of the JSC Leadership Development Program in 

2002. He received the Mark D. Heath Aircraft Engineering Award, the NASA Exceptional 

Service Medal and numerous NASA Group Achievement Awards. Watkins has a B.S. in 

Mathematics from Albany State University. 

Colonel Michael J. Bloomfield, U.S. Air Force 

Astronaut Office Operations Officer, NASA 

Colonel Bloomfield is a NASA astronaut who has logged more than 753 hours in space. The 

Space Shuttle veteran was a crewmember aboard Atlantis in 1997, Endeavour in 2000 and 

Atlantis in 2002. A Shuttle Commander and Pilot, he has served as Director of Shuttle 

Operations, Chief Instructor Astronaut, and Chief of Safety in the Astronaut Office. He was 

Astronaut Representative to the Columbia Accident Investigation Board. Before entering 

training at the Johnson Space Center in 1995, Bloomfield served as test pilot for all models of 

the F-16 at Edwards Air Force Base, as well as Safety Officer and Flight Commander for the 

416th Flight Test Squadron. From 1983 until 1991, he served as a combat-ready pilot and 

instructor pilot in the F-15. He completed the F-15 Fighter Weapons Instructor Course and 

was honored as a Distinguished Graduate of the U.S. Air Force Test Pilot School. In 1983 he 

won the Commanders Trophy as Top Graduate from Air Force Undergraduate Pilot Training. 

Bloomfield holds a B.S. in Engineering Mechanics from the U.S. Air Force Academy and an 

M.S. in Engineering Management from Old Dominion University. He was also 1980 Captain 

of the U.S. Air Force Academy Falcon Football Team. 

Page 166 of 216 
Final Report of the Return to Flight Task Group 

APPENDIX C – RTF TG STAFF

Name 

Shannon K. Bach 

Thomas E. Diegelman 

David B. Drachlis 

Maj. Gen. Joe H. Engle, 

U.S. Air National Guard (Ret.) 

Malise M. Fletcher 

Paula B. Frankel 

Lillian M. Hudson 

Dennis R. Jenkins 

Jennifer L. LeStourgeon 

Mario Loundermon 

Sharon J. Martin 

Susan E. Mauzy 

Lt. Col. George E. “Ned” Mueller, 

U.S. Marine Corps (Ret.) 

Lester A. Reingold 

Anna K. “Kitty” Rogers 

Susan K. Stone 

Barbara J. Teague 

Tamara R. West 

Role 

Administrative Support 

IVASP Support 

Public Affairs Officer 

Task Group Support 

Technical Panel Support 

Recorder 

Travel Coordinator 

Task Group Support 

Information Technology 

Report Cover Artist 

Budget Manager 

Task Group Support 

Management Panel Support 

Report Editor 

Project Manager 

Travel Coordinator 

Operations Panel Support 

Administrative Support 

Affiliation 

Valador, Inc. Consultant 

NASA Johnson Space 

Center 

NASA Marshall Space 

Flight Center 

Engle Technologies 

NASA Johnson Space 

Center 

Westover and 

Associates, Inc. 

Valador, Inc. Consultant

Valador, Inc. Consultant

NASA Johnson Space 

Center 

Valador, Inc.

Al-Razaq Computing 

Services 

NASA Johnson Space 

Center 

Valador, Inc. Consultant 

Valador, Inc. Consultant 

Valador, Inc. 

Valador, Inc. Consultant 

NASA Johnson Space 

Center 

NASA Johnson Space 

Center 

Page 167 of 216 
Final Report of the Return to Flight Task Group 

mated to 

ET-120 in the 

Vehicle Assembly 

Building at the 

with this ET 

Discovery

Kennedy Space 

Center; anomalies 

eventually forced the 

program to switch to 

ET-121 for STS-114. 

Page 168 of 216
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APPENDIX D – RTF TG FACT-FINDING ACTIVITIES 

June 2003 

June 10, 2003 NASA Headquarters, RTF TG Charter. 

June 24, 2003 Johnson Space Center, RTF TG Meeting with Managers for Space 

Shuttle and International Space Station. 

August 2003 

August 5-7, 2003 Kennedy Space Center, Plenary Meeting. 

August 18, 2003 Johnson Space Center, NASA-National Geospatial-Intelligence 

Agency (NGA) Memorandum of Agreement (MoA). 

August 19-20, 2003 Johnson Space Center, discussions with Space Shuttle Program, 

USA, and Boeing Management. 

August 21, 2003 Videoconference, Space Flight Leadership Council Meeting. 

August 25, 2003 Kennedy Space Center, Ground-based Imagery Discussions. 

August 27, 2003 Lockheed Martin Missiles and Fire Control, Dallas, Texas, 

Reinforced Carbon-Carbon Non-Destructive Inspection. 

August 28, 2003 Michoud Assembly Facility (MAF), External Tank Return to 

Flight Status. 

September 2003 

September 9-11, 2003 Johnson Space Center, Plenary Meeting. 

September 17, 2003 House Science Committee Members and Senior Staff visit. 

Charles G. 

Stevenson of the 

Kennedy Space 

Center (foreground) 

briefs staff and 

members of the 

Return to Flight Task 

Group during an 

August 5, 2003 visit 

to the Columbia 

Debris Hangar at the 

Kennedy Space 

Center. 

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September 17, 2003 Senate Committee on Commerce, Science and Transportation 

Members and Senior Staff visit. 

September 18, 2003 Johnson Space Center, Extravehicular Activity Tile and Reinforced 

Carbon-Carbon Repair. 

September 23, 2003 NASA Headquarters, CAIB Recommendation 9.1-1 Fact-Finding. 

September 24, 2003 Kennedy Space Center, Foreign Object Debris (FOD) and 

Non-Destructive Inspection. 

September 30, 2003 Michoud Assembly Facility, External Tank Return to Flight Status. 

October 2003 

October 3, 2003 Videoconference, Space Flight Leadership Council Meeting. 

October 8, 2003 Kennedy Space Center, Waivers and Deviations for Kennedy 

Space Center Ground Support Equipment. 

October 14, 2003 Washington, D.C., NASA-National Geospatial-Intelligence 

Agency (NGA) Memorandum of Agreement (MoA). 

October 20, 2003 Kennedy Space Center, Ground-based Imaging. 

October 20, 2003 House Science Committee Senior Staff visit. 

October 22-23, 2003 Ogden, Utah, Program Managers Review. 

October 27-28, 2003 NASA Headquarters, Submarine Safety Colloquium. 

Frank Benz of the 

Johnson Space 

Center in Houston, 

briefs members of 

the Return to Flight 

Task Group’s 

Technical Panel on 

the reinforced 

carbon-carbon 

(RCC) impact test rig 

during a fact-finding 

visit to the Southwest 

Research Institute in 

San Antonio, Texas 

on October 29, 2003. 

Task Group 

members and 

supporting staff are, 

from left, Sy 

Rubenstein, 

Astronaut Carlos 

Noriega, Rob 

Hammond, and Ben 

Cosgrove. 

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Final Report of the Return to Flight Task Group 

Return to Flight Task 

Group Technical 

Panel members and 

support staff inspect 

the External Tank 

planned for the 

STS-114 mission 

during a December 

2, 2003 fact-finding 

visit to the Michoud 

Assembly Facility 

near New Orleans. 

Lockheed Martin 

Space Systems 

Company’s Michoud 

Operations builds 

the External Tank for 

NASA at the facility. 

Johnson Space Center and Southwest Research Institute, San

Antonio, Texas, Thermal Protection System Meetings. 

Cape Canaveral, Florida, Service Life Extension Program Summit. 

Teleconference, Atlantis Nosecap Non-Destructive Inspection. 

Marshall Space Flight Center, SRB Bolt-Catcher Critical Design

Review. 

Johnson Space Center, JAXA Fact-Finding. 

Johnson Space Center, Management Meetings. 

Johnson Space Center, Mission Management Team Normal

Accident Theory. 

Johnson Space Center, Space Flight Leadership Council Meeting. 

Johnson Space Center, Mission Management Team Simulation 

(Flight 12A.1).

Michoud Assembly Facility, External Tank Status. 

Kennedy Space Center, Digital Closeout Imagery. 

Johnson Space Center, Plenary Meeting. 

October 28-30, 2003 

October 29-30, 2003 

October 31, 2003 

November 2003 

November 5-30, 2003 

November 12, 2003 

November 20, 2003 

November 20, 2003 

November 21, 2003 

December 2003 

December 3-4, 2003 

December 2, 2003 

December 3, 2003 

December 9-10, 2003 

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December 11-12, 2003 Marshall Space Flight Center, Space Shuttle Certification Status 

Review. 

December 16, 2003 NASA Headquarters, Space Flight Leadership Council Meeting. 

January 2004 

January 15, 2004 Johnson Space Center, STS-114 Flight Techniques Panel. 

January 22, 2004 Teleconference, Regarding R3.4-1, R3.4-2, R3.4-3, Imagery and 

R6.4-1, TPS Inspection and Repair with Mr. Steve Wallace (CAIB 

member). 

January 26, 2004 Teleconference, with Bryan O’Connor, Chief Safety and Mission 

Assurance Officer Regarding CAIB Recommendation 9.1-1. 

January 27, 2004 Teleconference, Jim Halsell Regarding Planning Framework for 

STS-114 and STS-121. 

January 28-30, 2004 Kennedy Space Center, SEIO Summit II. 

January 29, 2004 Johnson Space Center, Sub-nominal Bond Technical Interchange 

Meeting. 

February 2004 

February 2, 2004 Teleconference, ADM Harold W. Gehman (CAIB Chairman) 

February 3, 2004 Michoud Assembly Facility, External Tank Mini-Technical 

Interchange Meeting. 

February 3, 2004 Integrated Vehicle Assessment Sub-Panel, Organizational Telecon. 

February 4, 2004 Johnson Space Center, DTO 848 Preliminary Design Review. 

February 2-5, 2004 Kennedy Space Center, Launch and Landing Imagery Program 

Requirements Document Requirements Review. 

February 4, 2004 NASA Headquarters, ITEA Meeting. 

February 5, 2004 Johnson Space Center, STS-114 Joint Operations Panel #9 

Telecon. 

February 6, 2004 Kennedy Space Center, Solid Rocket Booster Thermal Protection 

System Mini-Technical Interchange Meeting. 

February 10, 2004 Johnson Space Center, Imagery Technical Interchange Meeting. 

February 11, 2004 Johnson Space Center, Mission Management Team Simulation. 

February 12, 2004 Teleconference, with Johnson Space Center MER Personnel 

Regarding SIMS Database. 

February 12-13, 2004 Johnson Space Center, Debris Summit II Summit. 

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Final Report of the Return to Flight Task Group 

February 17-18, 2004 Galveston, Texas, SLEP II Summit. 

February 18, 2004 NASA Headquarters, JAXA Fact-Finding. 

February 19, 2004 Johnson Space Center, Space Flight Leadership Council Meeting. 

February 19, 2004 Johnson Space Center, STS-114 Joint Operations Panel #10 

Telecon. 

February 18-19, 2004 Johnson Space Center, NASA-NGA MoA Meeting. 

February 20, 2004 Johnson Space Center, Integrated Vehicle Assessment Sub-Panel 

Meeting. 

February 24-25, 2004 NASA Headquarters, Management Panel Meetings. 

March 2004 

March 4, 2004 Johnson Space Center, STS-114 Joint Operations Panel #11 

Telecon. 

March 11, 2004 Kennedy Space Center, FOD and Digital Closeout Imagery. 

March 23-24, 2004 Johnson Space Center, OBSS Status Meeting. 

March 30, 2004 Johnson Space Center, STS-114 Joint Operations Panel #12 

Telecon. 

March 31, 2004 Sandia Labs, Albuquerque, New Mexico, OBSS Status Meeting. 

April 2004 

April 1, 2004 Kennedy Space Center, External Tank Monthly Review. 

April 2, 2004 Kennedy Space Center, Two-Person Closeout, Orbiter Hardening, 

and RCC Non-Destructive Inspection Briefings. 

April 2, 2004 Kennedy Space Center, Pre-Launch Mission Management Team 

Simulation. 

April 9, 2004 Kennedy Space Center, Two-Person Closeout, Orbiter Hardening, 

and RCC Non-Destructive Inspection Dry Run Briefings. 

April 12-15, 2004 Johnson Space Center, Plenary Meeting. 

April 28-30, 2004 Marshall Space Flight Center, SRB Bolt Catcher Delta Critical 

Design Review. 

May 2004 

May 14, 2004 Kennedy Space Center, Foreign Object Debris and Digital 

Closeout Imagery Status Review. 

May 19, 2004 Marshall Space Flight Center, SRB Bolt Catcher Critical Design 

Review Pre-board. 

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Final Report of the Return to Flight Task Group 

May 26, 2004 

May 27, 2004 

May 27, 2004 

 June 2004 

June 8-9, 2004 

June 9, 2004 

June 10, 2004 

June 14-15, 2004 

June 17, 2004 

June 22, 2004 

June 23, 2004 

June 25, 2004 

A full-scale Reusable 

Solid Rocket Motor is 

fired at ATK Thiokol 

Propulsion Division’s 

Promontory, Utah, 

test facility on June 

10, 2004. This motor 

tested modifications 

designed to enhance 

the safety and 

integrity of the Space 

Shuttle. Members of 

the Return to Flight 

Task Group 

observed the test 

during a fact-finding 

visit to the facility. 

Johnson Space Center, Mission Management Team Simulation #5. 

Johnson Space Center, Reinforced Carbon-Carbon Plug Repair 

Preliminary Design Review. 

Marshall Space Flight Center, SRB Bolt Catcher/NSI Pressure 

Cartridge Critical Design Review. 

Johnson Space Center, LDRI Orbiter Inspection System Critical 

Design Review. 

Ogden, Utah, Space Flight Leadership Council Meeting. 

Ogden, Utah, Engineering Test Motor Firing at ATK-Thiokol. 

Kennedy Space Center, Systems Engineering & Integration Office 

Summit . 

Johnson Space Center, Operations Panel Fact-Finding Telecon 

with Space Shuttle Program regarding CAIB Recommendation 

6.4-1. 

Langley Research Center, Virginia, Management Panel visit to the 

NASA Engineering and Safety Center regarding CAIB 

Recommendations 6.2-1, 7.5-1, and 7.5-2. 

NASA Headquarters, Management Panel visit regarding CAIB 

Recommendations 6.2-1, 7.5-1, and 7.5-2. 

Michoud Assembly Facility and Stennis Space Center, External 

Tank Monthly Review. 

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Final Report of the Return to Flight Task Group 

Return to Flight Task 

Group Management 

Panel members and 

staff meet with NASA 

officials during a factfinding meeting in 

Washington, D.C. 

June 23, 2004. 

Johnson Space Center, Tile Test Article Review. 

Kennedy Space Center, SIMS Production Tool Demonstration. 

Kennedy Space Center, Mission Management Team 

Simulation #6. 

NASA Headquarters, NASA Administrator’s Retreat on Agency’s 

Space Shuttle Return to Flight. 

Kennedy Space Center, Operations Panel Fact-Finding on Space 

Shuttle Program-3, Contingency Shuttle Crew Support. 

Kennedy Space Center, Fact-Finding on CAIB Recommendations 

4.2-5 and 10.3-1. 

Teleconference, Fact-Finding on CAIB Recommendation 3.2-1. 

Teleconference, Plenary for Conditional Closures to CAIB 

Recommendations 4.2-5 and 10.3-1. 

Johnson Space Center, Reinforced Carbon-Carbon Test Article 

Review. 

Johnson Space Center, Mission Management Team Simulation #7. 

Johnson Space Center, Integrated Vehicle Assessment Sub-Panel 

Fact-finding Meeting with Simulation Planning Team, Mission 

Management Team training community, and System Engineering 

and Integration Office on Thermal Protection System Integrated 

Operations Plan. 

Johnson Space Center, Technical Panel Fact-finding with Space 

Shuttle Program on Integrated Risk Assessment for CAIB 

Recommendation 3.2-1. 

June 28, 2004 

June 29, 2004 

June 30, 2004 

July 2004 

July 1, 2004 

July 8, 2004 

July 8, 2004 

July 16, 2004 

July 21, 2004 

July 26-27, 2004 

July 27-28, 2004 

July 27-28, 2004 

July 28, 2004 

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August 2004 

August 10, 2004 Kennedy Space Center, Operations Panel Fact-finding on Space 

Shuttle Program-3, Contingency Shuttle Crew Support. 

August 10-12, 2004 Johnson Space Center, Space Shuttle Program Impact Testing and 

Debris Summit. 

August 13, 2004 Johnson Space Center, R6.4-1 Strategy Session. 

August 16, 2004 Teleconference, Internal Review of CAIB Recommendation 4.2-1 

Closure. 

August 18, 2004 Johnson Space Center, Fact-Finding with Space Shuttle Program 

on CAIB Recommendations 6.3-1 and 7.5-3. 

August 18-19, 2004 Kennedy Space Center, External Tank TPS Certification Technical 

Interchange Meeting. 

August 25, 2004 Kennedy Space Center, External Tank Monthly Review. 

August 30, 2004 Kennedy Space Center, Management Panel and Operations Panel 

Fact-finding with Space Shuttle Program Workforce. 

August 30-3, 2004 Michoud Assembly Facility, ET Flange Critical Design Review. 

August 31-1, 2004 Johnson Space Center, Orbiter Boom Sensor System Design 

Review. 

September 2004 

September 1, 2004 Marshall Space Flight Center, Space Flight Leadership Council 

Meeting. 

September 3, 2004 Teleconference, Debris Summit Debrief. 

September 13, 2004 Johnson Space Center, Tile Repair System Design Review. 

September 13, 2004 Johnson Space Center, Integrated Vehicle Assessment Sub-Panel 

Fact Finding on TPS Integrated Operations Plan. 

September 14-16, 2004 Johnson Space Center, Plenary Meeting. 

September 22-23, 2004 Johnson Space Center, On-Orbit Mission Management Team 

Simulation. 

October 2004 

October 5-6, 2004 Ogden, Utah, RCC Plug Repair Technical Interchange Meeting. 

October 08, 2004, Washington, D.C., Meeting with OMB, OSTP, and White House 

staff. 

October 19-20, 2004 Marshall Space Flight Center, RCC Crack Repair Preliminary 

Design Review. 

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October 20-21, 2004 Michoud Assembly Facility, ET TPS Certification Technical 

Interchange Meeting. 

October 25-26, 2004 Kennedy Space Center, Ground Camera Ascent Imagery Project 

Critical Design Review. 

October 27, 2004 Teleconference, on Verification, Validation and Certification 

Definitions. 

October 28, 2004 NASA Headquarters, RTF TG Leadership Meeting. 

October 28-29, 2004 Johnson Space Center, RTF Flight Operations Progress Review. 

October 29, 2004 Videoconference, Space Flight Leadership Council Meeting. 

November 2004 

November 8-10, 2004 Johnson Space Center, Space Shuttle Program Impact Testing 

Debris Summit. 

November 9-10, 2004 Michoud Assembly Facility, External Tank TPS Certification 

Status Briefing. 

November 15, 2004 Johnson Space Center, Management Panel Briefing to the 

Aerospace Safety Advisory Panel. 

November 16, 2004 Johnson Space Center, Management Panel Fact Finding on 

CAIB Recommendation 6.3-1. 

November 16-18, 2004 Marshall Space Flight Center, SRB Bolt Catcher Design 

Certification Review Onsite Documentation Review. 

Return to Flight Task 

Group members and 

staff inspect the 

Space Shuttle 

External Tank being 

prepared for the 

STS-114 mission 

during a visit to the 

Michoud Assembly 

Facility in New 

Orleans November 

10, 2004. 

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November 16-19, 2004 

November 18, 2004 

November 22, 2004 

November 23, 2004 

November 30, 2004 

November 30-1, 2004 

November 30, 2004 

December 2004 

December 2, 2004 

December 3, 2004 

Return to Flight Task 

Group Management 

Panel Lead Dr. Dan 

L. Crippen, left, 

confers with 

Technical Panel 

Lead Joseph W. 

Cuzzupoli during a 

December 2004 factfinding plenary at the 

Marshall Space 

Flight Center in 

Huntsville, Alabama. 

Johnson Space Center, STS 114 On-Orbit Mission Management 

Team Simulation. 

Telecon with Space Shuttle Program on CAIB recommendation 

R3.3-2. 

Johnson Space Center, Space Shuttle Program Presents R3.3-2 and 

4.2-1 Closures to Technical Panel/Integrated Vehicle Assessment 

Sub-Panel. 

NASA Headquarters, Deputy Chief Engineer Presents R7.5-1 and 

R9.1-1 Closures. 

Johnson Space Center, Space Shuttle Program Presents R3.4-1, 

R3.4-2, R3.4-3 Closures to Operations Panel and Integrated 

Vehicle Assessment Sub-Panel. 

Johnson Space Center, RCC Plug Repair Technical Interchange 

Meeting #3. 

Marshall Space Flight Center, SRB Bolt Catcher Design 

Certification Review Pre-Board. 

Johnson Space Center, Cure-In-Place Ablator (CIPA) 

Critical Design Review. 

Marshall Space Flight Center, SRB Bolt Catcher Design 

Certification Review Board. 

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December 9, 2004 Videoconference, Space Flight Leadership Council Meeting. 

December 10, 2004 Marshall Space Flight Center, SRB Bolt Catcher Design 

Certification Review Delta Board. 

December 13, 2004 Johnson Space Center, Integrated Vehicle Assessment Sub-Panel 

Fact Finding on TPS Integrated Operations Plan. 

December 14-15, 2004 Marshall Space Flight Center, Plenary Meeting. 

December 15, 2004 Johnson Space Center, Space Shuttle Program Fact Finding on 

CAIB Recommendation 6.4-1. 

January 2005 

January 7, 2005 Johnson Space Center, Orbiter Return to Flight Working Group – 

Down Select for Repair Option Meeting. 

January 10-14, 2005 Johnson Space Center, Debris Summit. 

January 13, 2005 Johnson Space Center, Program Requirements Control Board – 

Down Select for Repair Option. 

January 21, 2005 Kennedy Space Center, Imagery Technical Interchange Meeting . 

January 24, 2005 Michoud Assembly Facility, External Tank Design Certification 

Review II. 

January 26-27, 2005 Johnson Space Center, R6.4-1 Fact Finding. 

January 27, 2005 Johnson Space Center, Component Simulation. 

February 2005 

February 2-3, 2005 Johnson Space Center, Japanese Space Agency (JAXA) FactFinding. 

February 7-10, 2005 Johnson Space Center, Orbiter Delta Design Certification Review. 

February 8, 2005 Washington, D.C., Imagery Technical Interchange Meeting. 

February 15, 2005 Teleconference Plenary for Conditional Closure of CAIB 

Recommendation 3.3-1. 

February 18, 2005 Videoconference, Space Flight Leadership Council Meeting. 

February 22-23, 2005 Kennedy Space Center, Systems Design Certification Review II. 

February 24-25, 2005 Michoud Assembly Facility, ET Design Certification Review II 

Pre-Board. 

February 25, 2005 Johnson Space Center, Component Simulation. 

February 25, 2005 Johnson Space Center, RCC On-Orbit Crack Repair Gun Critical 

Design Review. 

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Return to Flight Task 

Group Technical 

Panel members and 

staff observe Space 

Shuttle Solid Rocket 

Booster stacking 

operations in the 

Vehicle Assembly 

Building during a 

February 22, 2005, 

fact-finding visit to 

the Kennedy Space 

Center, Florida. 

February 28-March 7, 

2005 

March 2005 

March 8-9, 2005 

March 10, 2005 

March 15, 2005 

March 15, 2005 

March 21, 2005 

March 22, 2005 

March 24, 2005 

March 28, 2005 

March 29, 2005 

March 29-31, 2005 

Kennedy Space Center and Johnson Space Center, STS-114 

On-Orbit Mission Management Team Simulation. 

Michoud Assembly Facility, ET Design Certification Review I 

and II Board. 

Johnson Space Center, Space Shuttle Program Closure 

Presentation to Operations Panel and the Integrated Vehicle 

Assessment Sub-Panel on Space Shuttle Program-3, Contingency 

Shuttle Crew Support. 

Johnson Space Center, Space Shuttle Program Closure 

Presentation to Technical Panel and Integrated Vehicle Assessment 

Sub-Panel on CAIB Recommendation 3.2-1, ET Debris Shedding. 

Washington, D.C., Meeting with Congressman Calvert and Staff. 

NASA Headquarters, Management Panel Closure Discussion on 

CAIB Recommendations 9.1-1, 6.2-1, and 6.3-1. 

Johnson Space Center, Operations Panel Fact Finding with Mr. 

Wayne Hale, Deputy Space Shuttle Program Manager on Space 

Shuttle Program-3, Contingency Shuttle Crew Support. 

Johnson Space Center, Space Shuttle Program Closure 

Presentation Telecon with Technical Panel and Integrated Vehicle 

Assessment Sub-Panel on CAIB Recommendation 3.3-2. 

Johnson Space Center, Management Panel Splinter Session on 

Space Shuttle Program Closure Packages for CAIB 

Recommendations 9.1-1, 6.2-1, and 6.3-1. 

Johnson Space Center, Integrated Vehicle Assessment Sub-Panel 

Splinter Session on Final Report Comments. 

Johnson Space Center, Plenary Meeting. 

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April 2005 

April 4, 2005 Johnson Space Center, Stafford Task Force/Anfimov AEC Fact 

Finding. 

April 4, 2005 NASA Headquarters, RTF TG Meeting. 

April 5, 2005 Jet Propulsion Laboratory, California, RTF TG to ASAP 

Transition Meeting. 

April 6, 2005 Johnson Space Center, System Design Certification Review II 

Board. 

April 7-8, 2005 Teleconference, Operations Panel Mission Management Team 

Training Fact-Finding. 

April 7-9, 2005 Johnson Space Center, System Design Verification Review III 

(Debris) Board. 

April 12, 2005 Teleconference, Space Shuttle Program Fact Finding on Certificate 

of Flight Readiness Process. 

April 13, 2005 Johnson Space Center, RCC Repair Interim Design Review. 

April 19, 2005 Kennedy Space Center, Program Design Certification Review. 

April 20, 2005 Washington, D.C., RTF TG Co-Chair and Management Panel Lead 

Meeting with Congressmen Gordon and Udall and Staff. 

April 20, 2005 Washington, D.C., RTF TG Co-Chair and Management Panel Lead 

Meeting with House Science Committee Staff. 

April 25, 2005 Johnson Space Center, CAIB Recommendation 6.4-1 Fact Finding. 

April 26-27, 2005 Johnson Space Center, Delta System Design Verification Review 

III (Debris). 

April 26-28, 2005 Johnson Space Center, Operations Integration Plan Simulation #3 

Flight Day 04-06. 

May 2005 

May 3-4, 2005 Michoud Assembly Facility, Monte Carlo Inputs Review of 

External Tank Debris Data. 

May 4, 2005 Johnson Space Center, Mission Management Team Simulation 

#13, Contingency Shuttle Crew Support. 

May 9, 2005 NASA Headquarters, RTF TG Co-Chair Meeting with NASA 

Administrator. 

May 10, 2005 Johnson Space Center, Review of Debris Transport Validation. 

May 11, 2005 Johnson Space Center, Orbiter Impact and Damage Tolerance 

Models for RCC and Tile. 

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May 12, 2005 Johnson Space Center, R6.4-1 Closure Discussion with Space 

Shuttle Program. 

May 18, 2005 Michoud Assembly Facility, Foam Divot-Transport-Impact 

Damage Technical Interchange Meeting. 

May 24, 2005 Johnson Space Center, Ice Technical Interchange Meeting. 

May 25, 2005 Johnson Space Center, Unexpected Debris Review Foam DivotTransport-Impact Damage Technical Interchange Meeting. 

May 26, 2005 Johnson Space Center, Aerospace Corp. Go/No-Go Decision for 

Monte Carlo Analysis. 

June 2005 

June 2-3, 2005 Johnson Space Center, Debris Design Verification Technical 

Review Dry-Run. 

June 6-7, 2005 Johnson Space Center, Plenary Meeting. 

June 15, 2005 Johnson Space Center, R6.4-1 Closure Data Review. 

June 16-17, 2005 Johnson Space Center, Debris Verification Technical Review 

Dry Run. 

June 20, 2005 Michoud Assembly Facility, Bellows Heater Design Certification 

Review. 

June 22, 2005 Johnson Space Center, STS-114 Delta Safety and Mission 

Assurance Readiness Review. 

June 23, 2005 Kennedy Space Center, Delta Systems Design Certification 

Review. 

June 24, 2005 Kennedy Space Center, Final Debris Design Verification Review. 

June 25, 2005 NASA Headquarters, R3.2-1 and R3.3-2 Closure Data Review. 

June 27, 2005 NASA Headquarters, Plenary Meeting. 

June 28, 2005 NASA Headquarters, RTF TG Co-Chairmen and Panel Leads 

Meeting with NASA Administrator. 

July 2005 

July 1, 2005 Johnson Space Center, Japanese Space Agency (JAXA) FactFinding. 

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APPENDIX E – ACRONYMS 

AFB 

AFRSI 

ASAP 

ATOTS

BFS 

BST 

C-SiC 

CAD 

CAIB 

CDR 

CIA 

CIPA 

CIPAA 

CO2

CSCS 

DCR 

DFO 

DOAMS 

DoD

DTO

DVR

ECLSS 

EFM 

EPOCC 

ET 

EVA 

FACA 

FOD 

FRCS 

HDTV

HQ 

HSC

HSDT 

HST

JSC 

ICB 

ISS 

ITA

ITAR 

IVA 

IVASP

KSC 

KTM 

LCC 

LO2/LOX

LH2

LON 

MAF 

MAS 

MER 

MMT 

MoA 

MPP 

MR 

Air Force Base 

Advanced Felt Reusable Surface Insulation (TPS blankets) 

Aerospace Safety Advisory Panel 

 Advanced Transportable Optical Tracking System 

Backup Flight System (Orbiter avionics) 

Behavioral Science Technology, Inc. 

Carbon-Silicon Carbide 

Computer-Aided Design 

Columbia Accident Investigation Board 

Critical Design Review 

Central Intelligence Agency 

Cure In-Place Ablator 

CIPA Applicator 

 Carbon Dioxide 

Contingency Shuttle Crew Support 

Design Certification Review 

Designated Federal Official (FACA) 

Distant Object Attitude Measurement System 

 Department of Defense 

 Development Test Objective 

 Design Verification Review 

Environmental Control and Life Support System 

Equivalent Flow Model (Scheduling tool) 

Expanded Photographic Optic Control Center 

External Tank 

Extra-Vehicular Activity 

Federal Advisory Committee Act 

Foreign Object Debris 

Forward Reaction Control System 

 High Definition Television 

Headquarters 

 House Science Committee 

High Speed Digital Television 

 Hubble Space Telescope 

Johnson Space Center (Texas) 

Integration Control Board 

International Space Station 

 Independent Technical Authority 

International Traffic in Arms (Federal law) 

Intra-Vehicular Activity 

 Integration Vehicle Assessment Sub-Panel 

Kennedy Space Center (Florida) 

Kineto Tracking Mount 

Launch Commit Criteria 

 Liquid Oxygen 

 Liquid Hydrogen 

Launch-on-Need 

Michoud Assembly Facility (Louisiana) 

Manifest Assessment System (scheduling tool) 

Mission Evaluation Room 

Mission Management Team 

Memorandum of Agreement 

Material Processing Plan 

Material Review 

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MRB Material Review Board 

MSFC Marshall Space Flight Center (Alabama) 

NASA National Aeronautics and Space Administration 

NESC NASA Engineering and Safety Center 

NDE Non-Destructive Evaluation 

NDI Non-Destructive Inspection 

NGA National Geospatial-Intelligence Agency (formerly NIMA) 

NIMA National Imagery and Mapping Agency (now NGA) 

NOAX Non-Oxide Adhesive eXperimental 

NSI NASA Standard Initiator 

NSTS National Space Transportation System (Space Shuttle) 

O2 Oxygen 

OBSS Orbiter Boom Sensor System 

OIP Operations Integration Plan 

OMM Orbiter Major Modifications 

OMDP Orbiter Modification and Down Period 

OMRS Operation and Maintenance Requirements System 

ORM Orbiter Repair Maneuver 

OV-102 Columbia 

OV-103 Discovery 

OV-104 Atlantis 

OV-105 Endeavour 

PAL Protuberance Air Load (ramps on ET) 

PASS Primary Avionics Software System (Orbiter avionics) 

PDL Polymer Development Laboratories (TPS foam) 

PDR Preliminary Design Review 

POCS Photographic Optic Control System 

PR Problem Report 

PRCB Program Requirements Control Board 

PRR Production Readiness Review 

PTS Pad Tracker System 

RCC Reinforced Carbon-Carbon 

RFI Request for Information 

RPM R-bar Pitch Maneuver 

RSRM Reusable Solid Rocket Motor (propulsion part of SRB) 

RTF TG Return to Flight Task Group 

SDTV Standard Definition Television 

SEIO Systems Engineering and Integration Office (also SE&IO) 

SFLC Space Flight Leadership Council 

SiC Silicon Carbide 

SIMS Shuttle Image Management System 

SMA Safety and Mission Assurance 

SRB Solid Rocket Booster 

SRMS Shuttle Remote Manipulator System 

SSME Space Shuttle Main Engine 

SSP Space Shuttle Program 

SSPO Space Shuttle Program Office 

SSRMS Space Station Remote Manipulator System 

STS Space Transportation System (Space Shuttle) 

TPS Thermal Protection System 

TZM Titanium, Zirconium, Molybdenum (metal alloy) 

USA United Space Alliance 

WAVE WB-57 Ascent Video Experiment 

WLE Wing Leading Edge (on Orbiter) 

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being 

lifted to a vertical 

position in the 

Vehicle Assembly 

Building at the 

ith a 

Rocket Boosters and 

Discovery

transfer aisle of the 

Kennedy Space 

Center. After the 

Orbiter is vertical, it 

will be lifted into one 

of the high bays to 

be mated w

waiting stack of Solid 

an External Tank. 

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hangs in 

the Vehicle 

Tank separates, 

these doors close 

Discovery

the transfer aisle of 

Assembly Building at 

the Kennedy Space 

Center. The two 

green squares are 

the undersides of the 

umbilical well doors; 

after the External 

over the areas just 

outboard of them. 

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ANNEX A – INDIVIDUAL MEMBER OBSERVATIONS 

During two years of fact-finding, some members of the Task Group made observations that 

they believe should be brought to the attention of the NASA Administrator as he leads the 

Agency past the return to flight. Those observations, which are not related to the safety or 

operational readiness of STS-114, are presented in this annex. These are not Task Group 

observations but rather represent the views of the individual authors; where additional Task 

Group members have chosen to support these views, they are so identified. 

A.1 Observations by Maj. Gen. William A. Anders 

1. NASA’s response to the CAIB findings and the Agency’s support of the RTF TG: 

I believe that NASA as a whole has made a commendable effort in these regards. It has 

not been perfect or totally efficient, but that should be understandable for such a massive 

Agency-wide challenge coming out of the shock of the Columbia accident. 

2. Safety of Human Spaceflight and Space Shuttle operations: The Space Shuttle is a 

high-performance vehicle with thin margins as is necessary to support the very 

challenging field of human space flight. NASA has done a commendable job in 

addressing the issues raised by the CAIB report to the extent such issues can be addressed 

practicably. Nonetheless, the Space Shuttle will never be particularly safe. If the United 

States chooses to operate in this demanding environment, we need to be continually alert 

to minimize risk and be sure it is worth the gain. And, we should not be too surprised if 

or when another accident happens. 

3. America’s “vision” and NASA’s strategy for space exploration and exploitation: It is 

desirable and unavoidable that humans will explore and exploit space. The major 

questions are: how, and at what pace? A key necessity for implementing any successful 

strategy/vision is that the scope and pace be in balance with the available resources. This 

seems to have been forgotten or ignored by both the Executive and Legislative branches. 

Over the past four decades NASA has experienced an almost continuous series of cost 

overruns and performance short-falls; the Space Shuttle has been the “poster child” for 

this phenomenon. Apollo was established to demonstrate to Americans and the rest of the 

world that the United States was not a second-rate power as had been strongly suggested 

by Sputnik, Gagarin, and the “missile gap.” It was a jingoistic program during the height 

of the Cold War that was strongly supported by the American (tax-paying) public. That 

program was successfully demonstrated on July 19, 1969, when Neil Armstrong and 

Buzz Aldrin planted an American flag at Tranquility Base. Unfortunately, NASA and a 

host of space enthusiasts incorrectly assumed (hoped?) that America’s political will and 

financial support extended beyond that necessary to “beat the Soviets” (Apollo 11 and 

prior). These enthusiasts continued intense and expensive exploitation and exploration 

programs (e.g. up to Apollo 17, Space Shuttle, the International Space Station ...) while 

political and financial support waned. These ambitious new programs, coupled with the 

political necessity to maintain the Apollo-derived NASA infrastructure (Centers), put the 

Agency’s scope in serious imbalance with its resources. Such is still the case. Until hard 

choices are made to bring the Agency’s scope (the Vision for Space Exploration) into 

balance with its resources, we should not be surprised by future mishaps and short-falls in 

our currently over-stressed human space flight programs. Since it is not likely that the 

American public will provide Apollo-like support for the current vision, it seems that its 

scope and pace should be reduced to more realistic levels (balance). 

4. Make-up of the RTF TG: In my view, the Task Group was too large to carry out its 

charter effectively and efficiently. In addition, it would have been advisable to slant the 

talents of the Task Group members more toward those with experience in accident 

investigation, large-program management, and human space flight. 

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A.2 Observations by Dr. Dan L. Crippen, Dr. Charles C. Daniel, 

Dr. Amy K. Donahue, Col. Susan J. Helms, Ms. Susan Morrisey 

Livingstone, Dr. Rosemary O’Leary, and Mr. William Wegner 

Taken one-at-a-time, the RTF TG assessments of the NASA implementation of the CAIB 

return-to-flight recommendations may leave an impression of accomplishment that we believe 

does not present a comprehensive picture of NASA’s return-to-flight effort. Without a doubt, 

we share with NASA the same fervent desire to see the Space Shuttle Program successfully 

continue as a healthy, vibrant tribute to the achievements of human spaceflight. To this end, 

although it was not within the explicit charter of the Return To Flight Task Group, we have 

documented additional observations relevant the post-Columbia environment that we believe 

are important to share with NASA leadership to help them address what we perceive to be 

continuing challenges. This is not a set of conclusions, but is a detailed summary of persistent 

cultural symptoms we observed throughout the assessment process. 

We agree that the improvements to the Space Shuttle and its organization are real, and often 

significant. This is a tribute to the dedicated efforts of many people working hard at all levels 

and in all parts of the Agency. At the same time, we believe that the leadership and 

management climate that governed NASA’s return-to-flight effort was weak in some 

important ways that bear discussion. While we explicitly address the Space Shuttle return-toflight effort, we believe these organizational and behavioral concerns are still pervasive 

throughout the human spaceflight programs. 

These observations are not intended as criticism of the entire NASA workforce. We have 

stated several times – in this report and elsewhere – that within the “working levels,” much of 

the NASA and contractor workforce “got it” and we believe at least some have always gotten 

it. And, indeed, there are some capable leaders at NASA who also “get it.” 

Our observations also are not meant to diminish the achievements made in addressing the 

individual CAIB recommendations. The workforce performed to the best of its ability, often 

with little direction. We commend their efforts and recognize their accomplishments. We also 

believe, however, that leadership and managerial shortfalls generally made the return-to-flight 

effort more complicated, more costly, and lengthier than it needed to be. 

The Rogers Commission and the Columbia Accident Investigation Board (CAIB) reports are 

both rich in explanation of factors that have weakened NASA’s ability to effectively manage 

a high-risk program. Yet while NASA leadership was focused on the 15 CAIB return-to-flight 

recommendations, they missed opportunities to address the enduring themes of dysfunctional 

organizational behavior that the CAIB and other external evaluators have repeatedly found. 

As a result, in our view, many fundamental concerns persist. Our intent here is to present 

some of the most prominent of these that we observed. 

The advantage of hindsight, and the opportunity to second-guess decisions made since 

February 2003, permeates these observations. All of them were, however, written prior to the 

launch of STS-114. It is also important to recognize that the behaviors and attitudes described 

here were not chance occurrences that were observed only once or twice, but that emerged 

numerous times throughout the Task Group’s interactions with NASA. The intent of these 

observations is to help NASA leadership identify and rectify these concerns. We will address 

four main areas: rigor, risk, requirements, and leadership. At the conclusion of our discussion, 

we cite specific examples to support and clarify our observations. 

Rigor 

“Rigor” refers to the scrupulous adherence to established standards for the conduct of work. 

In NASA’s context, the safe and reliable execution of high-risk, complex technical endeavors 

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requires the rigorous and consistent understanding of, and adherence to, standard process. 

These processes should be enforced across all projects and elements, and preferably even 

across programs. Implementing standard processes across programs allows more consistent 

evaluations of the programs, and eases the transition of personnel moving from one program 

to another. As we observed them, the return-to-flight activities often demonstrated a lack of 

standard processes, and, in some cases, simply a lack of any process at all. 

One dilemma the Agency faced in this regard was how to communicate about its goals and 

standards of achievement. Once the Agency is on record as committed to a specific 

achievement, it becomes unpalatable to back off of that target for fear of appearing to fail. 

Instead, the adjustment of performance standards to allow a “best-effort” provides the 

appearance that the goal has been met, but without the rigor and discipline necessary do so 

safely or completely. Before making commitments to specific achievements, NASA should 

fully consider how much progress is feasible, and motivate public and private expectations 

accordingly. When achievements are mandatory at first but become “goals” when the going 

gets tough, it sends a strong message to everyone that nothing is mandatory. 

With the benefit of hindsight, the Agency’s unquestioned endorsement of, and commitment to 

comply with, the CAIB return-to-flight recommendations may have been laudable and 

reasonable – and perhaps even necessary under the circumstances the Agency faced at the 

time – but it may also have been a mistake. The endorsement of the CAIB recommendations, 

before conducting a thorough engineering and programmatic assessment of their implications, 

short-circuited a more traditional and rigorous process. NASA has long maintained a list of 

the hardware risks to the vehicle, and had an upgrades program in place before the Columbia 

accident. Ideally, NASA should have determined the importance of the CAIB 

recommendations in relation to the risks and upgrades it was already tracking. Then leaders 

should have prioritized the implementation of the CAIB recommendations against other 

desired risk mitigation efforts to determine the best expenditure of limited program resources 

to provide the largest reduction in overall risk. 

The change in National Policy dictating the Space Shuttle be retired in 2010 presented the 

Agency with an opportunity to re-evaluate the decision to fully implement all of the CAIB 

recommendations and to curtail actions that were proving to be unproductive or inefficient; 

NASA did not. 

In our view, NASA leadership should not have foregone their traditional process of 

conducting detailed assessments of proposed changes. The CAIB recommendations were 

important, but the accident board fully acknowledged that they had not considered their 

recommendations within the larger context of the Space Shuttle Program. In addition, before 

committing to a short-term launch date – that ultimately drove any number of important 

implementation decisions – NASA should have conducted detailed engineering assessments 

of the CAIB recommendations, traded them against other risk mitigation efforts, developed a 

clear understanding of the physics of foam loss, and devoted serious consideration of 

alternatives to “fix the foam;” e.g., Orbiter hardening or a redesigned External Tank. This 

would have allowed the program to determine how long a stand-down was necessary to 

implement a reasonable set of requirements to reduce the risk of flying the vehicle. 

As we reviewed the return-to-flight effort, it was apparent that there were numerous instances 

when an opportunity was missed to implement the best solution because of this false schedule 

pressure. As early as September 2003 the RTF TG was told that specific technical activities 

were not being performed because they could not meet the schedule. Too often we heard the 

lament: “If only we’d known we were down for two years we would have approached this 

very differently...” 

This overall lack of integrated planning resulted in ad hoc and redundant efforts. Even the 

NASA Implementation Plan disappoints: it has no document number, no change history, and 

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no clear place in the program’s effort. Its subtitle – “A periodically updated document 

demonstrating our progress ...” – makes clear that it is not an executable “plan” but, instead, a 

status report. Many of the lower-level “plans” that were presented in formal meetings were 

developed after implementation was initiated, instead of setting clear objectives and 

acceptance criteria before the work was begun. Activities were undertaken without an 

understanding of how they contributed to the overall return-to-flight effort and without any 

sense of budgetary or other limits. As a result, at the end of 2-1⁄2 years and $1.5 billion or 

more, it is not clear what has been accomplished. 

While solving the technical problems associated with return to flight was always seen as the 

highest priority, the cost associated with accomplishing this was for the most part neither 

effectively monitored nor managed. In fact, many of the return-to-flight efforts were initiated 

at mid- to lower-levels with little visibility or traceability to the Space Shuttle Program level 

(Level II). These factors have combined to allow for uncontrolled cost growth and an overall 

lack of cost management. If the return-to-flight effort had been better managed to control 

costs, it is possible that funding would exist to upgrade the Orbiter with newer systems and 

eliminate risks posed by hardware not involved in the Columbia accident. 

We also observed that instead of concise engineering reports, decisions and their associated 

rationale are often contained solely within Microsoft PowerPoint® charts or emails. The CAIB 

report (Vol. I, pp. 182 and 191) criticized the use of PowerPoint as an engineering tool, and 

other professional organizations have also noted the increased use of this presentation 

software as a substitute for technical reports and other meaningful documentation. PowerPoint 

(and similar products by other vendors), as a method to provide talking points and present 

limited data to assembled groups, has its place in the engineering community; however, these 

presentations should never be allowed to replace, or even supplement, formal documentation. 

Several members of the Task Group noted, as had CAIB before them, that many of the 

engineering packages brought before formal control boards were documented only in 

PowerPoint presentations. In some instances, requirements are defined in presentations, 

approved with a cover letter, and never transferred to formal documentation. Similarly, in 

many instances when data was requested by the Task Group, a PowerPoint presentation 

would be delivered without supporting engineering documentation. It appears that many 

young engineers do not understand the need for, or know how to prepare, formal engineering 

documents such as reports, white papers, or analyses. 

Another disturbing trait that we observed was that personalities were allowed to dominate 

over strict process – examples exist of strong personalities attempting to avoid process and 

others allowing avoidance to occur. Many in senior leadership observed these lapses in 

process, but did little to correct the situation. For example, during the System Design 

Certification Review (DCR) II on February 23, 2005, a senior program manager commented 

that, “It is no longer an important question as to whether or not any given item is certified. 

Some things won’t be certified ... Items don’t have to be certified to fly, and we can even get 

waivers for the safety cert if need be.” It was astounding that there was no rebuttal to this 

statement, even though the individual was not the most senior person at the table. This 

mocking of rigor sends a message to junior staff that it is acceptable to modify or avoid 

established processes. As a result, both organizational and individual accountability fell by the 

wayside. Senior leadership should not trivialize established processes since their attitudes can 

be infectious, either to the benefit or detriment of the Space Shuttle Program and the Agency. 

Risk 

The CAIB report (Vol. I, p. 193, F7.4-3) states: “Over the last two decades, little to no 

progress has been made toward attaining integrated, independent, and detailed analyses of risk 

to the Space Shuttle System.” In terms of the propensity to accept cumulative risk, the CAIB 

noted (Vol. I, p. 139): “These little pieces of risk add up until managers are no longer aware 

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of the total program risk, and are, in fact, gambling.” Throughout the return-to-flight effort, 

we observed these propensities still exist. 

Very few human endeavors, particularly related to high energy activities involving advanced 

technologies, are completely free of risk. Spaceflight in general and human spaceflight in 

particular, is such that it is impossible to drive the risk to zero. Most who have led high risk, 

technical organizations will readily admit one of the greatest threats resides is unknown, 

unrecognized, or unacknowledged risks. Ultimately, all three of NASA’s human spaceflight 

mishaps resulting in crew loss fell prey to one or more of these. To eliminate these threats, 

successful risk management approaches mandate thorough, ongoing, and critical assessments 

of potential individual and systemic vulnerabilities. While the return to flight efforts may have 

reduced some known risks, Space Shuttle missions will always be “accepted risk” operations. 

NASA must be vigilant to prevent the development of a false sense of security by accepting 

faulty assumptions, or otherwise inappropriate analyses, to justify continued Space Shuttle 

missions. The vehicle is not inherently unsafe, but it demands a high degree of vigilance to fly 

safely. 

Unfortunately, we do not believe the risk management processes in place within the Space 

Shuttle Program are sufficiently robust. One telling sign is the program’s development of a 

document entitled, The Integrated Risk Acceptance Approach For Return To Flight, which 

was revised several times during early 2005. This narrative has little substance regarding 

classical risk management. It is more a brief status report on a list of known and significant 

risks, noting where risk has been “accepted,” with no rationale or explanation. The document 

exhibits the very lack of accountability we referenced previously: it does not have an official 

document number, has no change history, appears not to be under configuration management, 

lists no authors, and has no approval signatures. The Task Group was informed that this 

document did not reflect the complete integrated risk acceptance for the return to flight, but to 

our knowledge, a total integrated risk acceptance rationale was never provided to the Task 

Group. 

We note that NASA managers also tend to confuse the exhaustive and laudable Integrated 

Hazard Report system with integrated risk management. The Space Shuttle Program has 

executed a thorough review of all Integrated Hazard Reports on its own initiative and at a 

considerable cost in hours and funds. As commendable as this effort has been, the review of 

thousands of Integrated Hazards does not constitute, nor should it be a substitute for, a 

comprehensive integrated risk management approach. 

Throughout the return-to-flight effort, there has been a reluctance to appropriately 

characterize the risks inherent in the Space Shuttle Program. As an example, it has proven 

irresistible for some officials to characterize the modified External Tank as “safer,” the “safest 

ever,” or even “fixed,” when neither the baseline of the “old” tanks nor the quantitative 

improvement of the “new” design has been established. The tank may well be safer, but 

without adequate risk assessment based on objective evidence it is impossible to know. 

The CAIB noted (Vol. I, pp. 118, 189-190, 200) that as the Space Shuttle became 

“operational,” NASA did not sustain the rigorous risk identification, assessment, management 

capabilities, or mindset required for what in reality was a developmental vehicle operating in 

a high-risk environment. Prior flight history became, incorrectly, an accepted risk rationale. In 

the end, few human spaceflight activities are more important than identifying and assessing 

the residual risk to flight and determining if it is acceptable from both a cumulative and 

integrated perspective. It is axiomatic that a fundamental capability of a “high-risk” agency is 

the ability to analyze risk, and failure to do so rigorously is a failure of leadership. 

It is ironic that the Space Shuttle will need to be treated as a developmental vehicle even as 

the program is winding down toward retirement; the risks of the last flight will be every bit as 

great as the risks for each of the flights before it. History has shown that leadership has 

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Final Report of the Return to Flight Task Group 

occasionally, but boldly, made the wrong choices and has been too easily convinced that the 

risk is acceptable. For the future of manned spaceflight, NASA leadership must protect 

against such tendencies. 

Requirements 

The Space Shuttle Program does not seem to have a basic understanding of what requirements 

are, what they can do for the program, and what they can do to the program. In many cases 

during the return-to-flight effort, hardware was built or modified, and models or analysis tools 

were coded and used, before any requirements were generated. This was explained by one 

program official as, “... if this were ‘business as normal’ ... we would follow the classic 

approach of defining requirements first. Return to flight is not in that mode, if we want to fly 

anytime soon.” The fact was, they didn’t fly anytime soon, partly because they did not have 

adequate requirements. The same program official continued, “We are pushing for answers on 

RCC vulnerability, test results on debris allowables, best available resolution for imagery – 

best effort across the board – without really knowing what the requirements are.” We are not 

convinced that implementing changes to man-rated systems without first defining 

requirements is a desirable approach. The lack of requirements also partially explains the 

difficulties the program has in determining how to verify, validate, and certify the new 

capabilities, and how to adequately determine how much remaining risk needs to be accepted. 

The discipline of defining integrated requirements before embarking on implementation 

allows an overall picture of work to be done, including associated interdependencies. This in 

turn facilitates prioritization of those requirements and therefore also prioritization of tasks to 

be done. Had this been accomplished, NASA would have been in better position to determine 

which tasks should have been constraints to the return to flight and which should not. This 

would also have allowed the development of proper schedules and plans, the generation of 

reasonable budget and resource estimates, and their allocation as established by priorities. As 

it was, it seemed that when it became apparent that a particular function would not be 

completed before return to flight (e.g., TPS repair), the program simply decreed that it was no 

longer mandatory for STS-114. 

Because of this lack of discipline, the Space Shuttle Program experienced instances where 

flight hardware was manufactured, accepted, and manifested prior to the completion of design 

reviews and the release of approved engineering documentation. Major testing and design 

activities were undertaken without specific requirements or success criteria. In some cases, 

the program simply refused to write down requirements, citing the “work” as more important 

than documentation. Lacking specific direction from the program, working-level personnel 

proceeded to perform test, design, and analysis activities based on their best guess of what 

was required. This resulted in designs that failed to meet the requirements that were ultimately 

written, tests that did not apply to the actual environments, models based on flawed 

assumptions, and a general expenditure of resources in an uncoordinated manner. 

It is recognized that even with correctly-written requirements, non-conformances will exist on 

either a temporary or permanent basis. These non-conformances need to be documented, 

completely assessed, and formally presented to management for a determination if the 

requirement should be changed, waived, or if it should be met as-stated and the nonconformance eliminated. Although a process exists to manage this, it is not rigorously 

followed in all instances. 

The Space Shuttle Program has been repeatedly cited for having too many waivers, and has 

become reluctant to add additional waivers, choosing instead to “beat” the system by using 

other means. Evidence of this involved open work on the External Tank despite its generally 

rigorous process. Numerous open items came out of the External Tank DCR. Instead of 

capturing each one of these as a separate piece of open work, the ET Project announced at the 

February 24-25, 2005, DCR pre-board that it would document them in a “Verification 

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Limitations Document.” While it is laudable that the project at least captured the deficiencies 

in the certification (unlike some others), the stated rationale for this approach was that the 

Verification Limitations Document would negate the need for any waivers. This, in effect, 

clouds the number of requirements that are not being met and diminishes the certification of 

the External Tank. 

The Use of Models 

As part of the return-to-flight effort, NASA initiated the development of a suite of more than 

20 new models to assist in assessing both pre- and post-launch risk. Standard engineering 

practice calls for objectives (requirements and interface definitions) to be established prior to 

development for any model or system of models, and processes and criteria defined for 

validating and verifying the model’s results. Also, it is not unusual for a peer review by 

outside experts to be employed, especially to evaluate systems of complex models that are by 

necessity inter-related but do not naturally resolve themselves to systemic specification. 

Initially, we did not observe these normal processes being followed during the development 

of these models, and a formal request by Ralph Roe of the NESC for a stand-down to evaluate 

the completed works was ignored. Later the NESC and other organizations did undertake 

limited peer reviews. 

In the case of debris analysis, models for: 1) debris liberation; 2) aerodynamic characteristics 

of the debris; 3) transport analysis of debris; 4) impact tolerance of the thermal protection 

system; and, 5) the resultant thermal and structural models of the effects of damage, are all 

necessary to assess risk. The uncertainties in one model (or system) inherently feeds into and 

compounds the uncertainty in the second model (or system), and so on. It appears, however, 

that NASA largely designed these five classes of models without the attention to the 

interdependencies between the models necessary for a complete understanding of the end-toend result. Understanding the characteristics of, and validating and verifying, one type of 

model without examining the implications for the end-to-end result is not sufficient. 

Further compounding the modeling challenge is the fact that the models most often used for 

debris assessment are deterministic, yielding point estimates, without incorporating any 

measure of uncertainty in the result. Methods exist to add probabilistic qualities to the 

deterministic results, but they require knowledge of the statistical distribution of the many 

variables affecting the outcome. Typically, the distributions of the “independent” variables 

would be derived from empirical observation. In the case of spaceflight, however, empirical 

evidence is often limited or non-existent, so theoretical or engineering distributions must be 

substituted. The probabilistic analysis therefore is very dependent on the quality of the 

assumptions made by the developers. Although they evaluated some of the assumptions used 

by the model developers, the NESC end-to-end “peer review” primarily analyzed whether the 

output of one model could be incorporated into the next, not the joint probability associated 

with any given output ... without which it is difficult to know the reliability of the result. 

Probability distributions are analytic methods necessary when assessing risk. Without an 

understanding of the likelihood of an outcome, risk acceptance is a judgment based on instinct 

and experience. But, as the Columbia accident showed, in a high risk environment that 

involves many unknowns like human space flight, experience and instinct are poor substitutes 

for careful analysis of uncertainty. This requires that analytical models be used appropriately 

to inform decisions within a rigorous engineering process. 

Leadership 

Leadership is critical to the success of any organization of the size and complexity of NASA. 

Without leadership the organization lacks cohesiveness and its goals lack coherence, resulting 

in wasted resources and, potentially, compromised products. A true leader is one who 

creates/coerces/compels/attracts/demands a responsive organization. It is never enough for a 

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leader to say: “I made that decision, what more do you want me to do?” Instead, at NASA, 

leaders must follow through to ensure decisions are executed with the rigor and discipline 

necessary for safe human spaceflight. 

Nonetheless, what our concerns about rigor, risk, and requirements point to are a lack of 

focused, consistent, leadership and management. What we observed, during the return-toflight effort, was that NASA leadership often did not set the proper tone, establish achievable 

expectations, or hold people accountable for meeting them. On many occasions, we observed 

weak understanding of basic program management and systems engineering principles, an 

abandonment of traditional processes, and a lack of rigor in execution. Many of the leaders 

and managers that we observed did not have a solid foundation in either the theory or practice 

of these basic principles. As the CAIB noted (Vol. I, p. 223, O10.12-1), “Unlike other sectors 

of the Federal Government and the military, NASA does not have a standard agency-wide 

career planning process to prepare its junior and mid-level managers for advanced roles.” In 

fact, NASA’s early successes are rooted in program management techniques and disciplines 

that few current managers in the human spaceflight arena have been willing to study. As a 

result, they lack the crucial ability to accurately evaluate how much or how little risk is 

associated with their decisions, particularly decisions to sidestep or abbreviate any given 

procedure or process. 

It is essential that senior managers have previously-demonstrated program management and 

systems engineering skills and a dedication to well-established, rigorous principles as they 

apply to complex, geographically and organizationally dispersed programs. More to the point, 

we remain concerned that NASA senior leadership did not recognize or correct this, and 

indeed sent contrary signals that the rigor and discipline of a sound program management 

process was not required. 

The Role of Accountability 

A crucial factor in creating a responsive and responsible organization is accountability. 

Within the human spaceflight programs, the lack of accountability appears to be pervasive, 

from the failure to establish responsibility for the loss of Columbia, up to and including a 

failure to require an adequate risk assessment of the next flight. While accountability takes 

many forms, to inculcate an organization and its culture with accountability requires, at a 

minimum, the consistent setting of expectations, as well as appropriate consequences for not 

meeting them. This is an important role of a leader. If no one, or no part of the organization, is 

held accountable for failing to meet those expectations, performance becomes simply a case 

of “best effort” – a term that became common during many return-to-flight discussions. 

A general attitude within the Space Shuttle Program seems to be that best-effort is a 

satisfactory substitute for meeting specific technical requirements; often requirements were 

not even documented to avoid the chance they could not be met. However, best-effort is a 

very poor substitute for a thorough understanding of the technical situation. Parts of the 

Agency seem to have forgone their traditional engineering rigor in favor of “when you have 

done your best effort, you are good to go.” This is not an appropriate philosophy for a highperformance organization that routinely puts the lives of its employees into high-risk 

situations. As Richard Feynman pointed out in his appendix to the Rogers Commission report, 

“... reality must take precedence over public relations, for nature cannot be fooled.” 

Although not described as such, the CAIB noted many of the symptoms of an organization 

operating with a best-effort attitude. The accident board wrote, “... traits and organizational 

practices detrimental to safety were allowed to develop, including: reliance on past success as 

a substitute for sound engineering practices (such as testing to understand why systems were 

not performing in accordance with requirements); organizational barriers that prevented 

effective communication of critical safety information and stifled professional differences of 

opinion; lack of integrated management across program elements; and the evolution of an 

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informal chain of command and decision-making processes that operated outside the 

organization’s rules” (CAIB, Vol. I, p. 9). Yet we witnessed the best-effort approach during 

the return-to-flight effort; we saw it in the NASA responses to Task Group requests for 

information (RFI), observed it during briefings, and experienced it while processing the 

closure packages sent to us by the Space Shuttle Program. 

Since NASA leadership had few rigorous requirements or expectations for CAIB compliance, 

the closure packages, which should have represented the auditable, documented status of the 

NASA implementation of the CAIB recommendations, tended to rely on mass, rather than 

accuracy, as proof of closure. The closure packages showed an organization that apparently 

still believes PowerPoint® presentations adequately explain work and document 

accomplishments. Our frustration with these packages drew the response that the engineering 

teams able to provide the detail were too busy preparing for launch and “doing real work” to 

properly document their actions. The inadequate and disorganized closure packages 

frequently required significant effort to obtain even minimally essential documentation. The 

packages themselves were often provided prematurely presumably (and sometimes with direct 

request) to seek guidance on “what it would take” to get the Task Group to “pass the 

recommendation.” 

Individual accountability – what the Agency is now calling “technical conscience” – can 

overcome the best-effort malaise if accompanied with sufficient positive and negative 

consequences. Part of being accountable, providing more than best-effort, includes having a 

well thought-out, focused plan prior to beginning implementation. Technical conscience 

provides the impetus to carry out those plans with rigorous adherence to engineering 

discipline. We feel significant progress can be made if this new technical conscience can be 

spread throughout the Space Shuttle Program and the rest of NASA. 

Attitude and Learning 

The CAIB noted an air of “arrogance” within NASA that led leaders and managers to be 

dismissive of the views of others, both within the organization and, especially, from outside 

the Agency. A less critical way to describe the phenomenon is one of “comfort” – comfort 

with existing beliefs, comfort with past experience, and comfort with information developed 

inside NASA. As an excuse for not listening, especially to criticism from outside the agency, 

NASA often proclaims itself to be unique. We readily admit that few organizations of any 

type – governmental, academic, or commercial – do the kind of work NASA does. Although 

the end product may be different, however, many of the processes are not different from those 

found in many large organizations. Whatever the source of this apparent insularity, it is 

inappropriate for an agency that routinely operates in a high-risk environment. The recurrence 

of apparently preventable accidents and the seeming unwillingness to learn should be 

sufficient to instill some humility to temper what often looks like arrogance. During the past 

two years, we have not witnessed very much of such humility. 

During the return to flight effort, even while NASA was systematically encouraging everyone 

to speak up and many processes were opened to more participation, the result was still very 

much the same as before the accident – roles, positions, and strength of personality often 

determined critical outcomes more than facts and analysis. More people were talking, but not 

many more were listening. 

Not listening manifests itself in other ways. It appears to us that NASA, unlike most highperformance organizations, rarely studies its own, or anybody else’s, mistakes; the CAIB also 

commented on this trait (CAIB Vol. I, p.11). It is widely believed that organizations that study 

and learn from small mistakes can often avoid larger ones. Conversely, those who do not learn 

as they go have no experience base to help avoid the big mistakes – such as the Challenger 

and Columbia accidents. An organization that places little value on sustained improvement 

from prior mistakes will tend to repeat them and certainly will not effectively carry the 

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necessary lessons forward to other programs. We have seen little evidence of renewed 

commitment to learning lessons from past mistakes at NASA. 

For instance, while many academic and government entities use the Challenger accident as a 

case study, ironically the human spaceflight programs do not. Similarly, NASA scarcely 

considers lessons from other organizations involved in high-risk endeavors, such as the 

Navy’s courses on the Scorpion and Thresher submarine accidents and its SUBSAFE 

program. As stated in the CAIB Report, Chapter 7, “The submarine Navy has a strong safety 

culture that emphasizes understanding and learning from past failures. NASA emphasizes 

safety as well, but training programs are not robust and methods of learning from past failures 

are informal.” Although NASA has maintained a “lessons learned” system since 1992, the 

human spaceflight activities appear not to have embraced it. 

In addition to not being willing to learn from mistakes, many NASA managers are not willing 

to learn from success, either. NASA’s early successes, as well as many in DoD are rooted in 

program management techniques and disciplines that few managers in the human spaceflight 

arena have been willing to study. Having apparently not done so, they lack the ability to 

accurately evaluate how much or how little risk is associated with sidestepping or 

abbreviating any given procedure or process. 

Summary 

It is difficult to be objective based on hindsight, but it appears to us that lessons that should 

have been learned have not been. Perhaps we expected or hoped for too much. The CAIB 

report should have served NASA as a “wake-up” call. As the CAIB noted (Vol. I, p. 208), 

“The recognition of human spaceflight as a developmental activity requires a shift in focus 

from operations and meeting schedules to a concern for the risks involved. Necessary 

measures include ... Barring unwarranted departures from design standards, and adjusting 

standards only under the most rigorous, safety-driven process.” 

We expected that NASA leadership would set high standards for post-Columbia work. We 

expected upfront standards of validation, verification and certification. We expected rigorous 

and integrated risk management processes. We expected involved and insightful leadership 

from NASA Headquarters. We were, overall, disappointed. 

There certainly are capable leaders to be found in the Space Shuttle Program and throughout 

NASA. In our view, though, the return-to-flight effort, when taken as a whole, was not 

effectively led or managed. The absence of accountability, of having managers dedicated to 

program management processes, and of managers being assigned to programs only after 

demonstrating these skills are what we believe to be the causes of the surface-level symptoms 

we saw so often. In particular, leadership and managerial failures to set expectations and 

requirements and a failure to hold people accountable; these promoted a lack of engineering 

rigor, discipline, and integrated risk assessment. Ultimately, this cost the program significant 

time and money while producing, in some areas, suspect, disappointing and/or inadequate 

results. Learning the lessons of these failures is important to NASA’s future. 

Conclusion 

Among the most damning observations CAIB made of NASA was the sense of complacency 

toward the problem of the External Tank shedding of foam. Despite program requirements 

that no debris should be shed, there were over 15,000 instances of damage to the Orbiter, most 

of which came from debris from the Space Shuttle elements. As has been widely reported, 

two flights before Columbia, a large piece of foam was shed and caused minor damage to one 

of the Solid Rocket Boosters. Photographic documentation was available of major foam 

shedding from the External Tanks on at least seven previous flights (CAIB Vol. I, p. 85). 

Despite all this evidence, foam had never destroyed an Orbiter and the program relied on this 

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“flight history” to justify inactivity before and during the flight of Columbia. 

This “We’ve seen this before” mentality is still present, and it appeared on more than one 

occasion during MMT simulations. In addition, leading up to the return-to-flight, the program 

justified not pursuing potential ice damage to the Orbiter umbilical doors because there had 

not been substantial damage on previous flights. Despite the evidence of impacts all around 

the area, the official rationale for accepting the risk was listed as “flight history;” i.e., we’ve 

never had critical damage there before. 

NASA’s leaders and managers must break this cycle of smugness substituting for knowledge. 

NASA must be able to quantify risk, even if imperfectly, set requirements and expectations, 

and hold organizations and individuals accountable, Analytical models – while valuable tools 

– cannot substitute for engineering judgment and conscience. Rigor must be reestablished 

throughout the Agency. Opinion, no matter how well informed, cannot replace objective 

evidence. Flight history, while critical for informed judgment, cannot substitute for it. “We’ve 

been lucky” is a statement that should never be associated with the human spaceflight 

programs. 

Perhaps most disturbing is the engineering legacy that seems to be developing within NASA. 

As with many professions, the basics of engineering are learned in school. However, good 

engineering practices – such as rigor in process and documentation – are learned outside the 

classroom in an apprentice-like environment. These practices are passed onto future 

generations as part of the “culture” of an organization. However, when an organization loses 

focus on its core values, the effects stretch far beyond the present because those principles are 

no longer passed onto future generations. Senior leaders do not appear to be concerned with 

following defined processes and are passing this legacy on to future leaders. 

In order to properly prepare the Agency for the future, including the return to the Moon and 

journey to Mars, we offer the following suggested actions, all of which must start at the top 

and flow down to the programs, projects, and workforce: 

1) Clearly set achievable expectations and hold people accountable; in addition to 

positive consequences, this includes negative consequences for not performing 

to expectations; 

2) Return to classic program management and systems engineering principles and 

practices (including integrated risk management), and execute these with rigor; 

3) Ensure managers at all levels have a solid foundation in these attributes before 

appointing them to such responsibilities; this requires not only training, but 

successful demonstration of these skills at a lower level; 

4) Eliminate the prejudices and barriers that prevent the Agency, and especially the 

human spaceflight programs, from learning from their own and others’ mistakes. 

NASA needs to learn the lessons of its past ... lessons provided at the cost of the lives of 

seventeen astronauts. 

Specific Examples 

The examples that follow this narrative are just that – examples. However, the behaviors and 

attitudes were not random events that were seen merely once or twice, but numerous times 

throughout the Task Group’s interactions with NASA. Many of the examples presented are 

not intended as detailed case studies, but are meant to provide evidence demonstrating 

behaviors of concern. We offer these observations for consideration and future improvement. 

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Rigor Example 1 

From our vantage point, the process for selecting a launch date was flawed, if indeed there 

was a process. We understand these were not normal circumstances, and the usual processes 

used to establish launch dates – hardware processing templates and payload readiness, to 

name two – were not applicable. However, we feel that the establishment of launch dates that 

seemingly did not take into account the full ramifications of the analysis and development 

efforts being conducted ultimately proved detrimental to the program. 

As discussed in the narrative of this observation, we feel the program should have begun the 

return-to-flight effort with a process that determined what work needed to be accomplish to 

return to flight, what the interdependencies were among that work, then develop schedules 

that supported the execution of the work. This process would have helped determine which 

efforts needed to be accomplished first since their results were required by other efforts. For 

example, determining the damage tolerance of the Orbiter before giving the ET Project their 

debris allowables requirements would have helped ensure the tank modifications would 

eliminate the appropriate debris. Establishing the RCC damage thresholds early would have 

provided the OBSS effort with their inspection criteria. 

Instead, it appears to us that senior management selected launch dates based on non-technical 

concerns, ultimately placing unnecessary and unrecoverable restrictions on teams working 

return-to-flight hardware development. In addition, several important requirements – such as 

the critical damage and debris size – were scheduled to be finalized at FRR, far too late to 

influence the products being provided by the External Tank Project, OBSS, and other 

systems. In addition, the constant setting of a launch date only a few months away never 

allowed the development efforts to take full advantage of the ultimate two-year stand-down; 

we heard several times that different solutions to various problems would have been selected 

if launch had not been 90 days away. 

Scheduled Return-to-Flight Launch Dates 

Meeting Date STS-114 Launch Date Days Until Launch Months Until Launch 

Jan 29, 2003 Mar 01, 2003 31 1.0 

Feb 10, 2003 Mar 01, 2003 19 0.6 

Feb 11, 2003 Apr 03, 2003 51 1.7 

Feb 24, 2003 Apr 03, 2003 38 1.3 

Feb 25, 2003 Jul 21, 2003 146 4.9 

Apr 16, 2003 Jul 21, 2003 96 3.2 

Apr 17, 2003 Oct 01, 2003 167 5.6 

May 21, 2003 Oct 01, 2003 133 4.4 

May 22, 2003 Dec 18, 2003 210 7.0 

Jul 28, 2003 Dec 18, 2003 143 4.8 

Jul 29, 2003 Mar 11, 2004 226 7.5 

Oct 05, 2003 Mar 11, 2004 158 5.3 

Oct 06, 2003 Sep 12, 2004 342 11.4 

Mar 08, 2004 Sep 12, 2004 188 6.3 

Mar 09, 2004 Mar 06, 2005 362 12.1 

Oct 28, 2004 Mar 06, 2005 129 4.3 

Oct 29, 2004 May 12, 2005 195 6.5 

Feb 15, 2005 May 12, 2005 86 2.9 

Feb 16, 2005 May 14, 2005 89 2.9 

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Apr 06, 2005 (SFLC) May 15, 2005 39 1.3 

Apr 19, 2005 (SFLC) May 22, 2005 33 1.1 

Apr 29, 2005 (HQ) July 13, 2005 75 2.5 

Jul 13, 2005 (scrub) July 16, 2005 3 0.1 

Jul 16, 2005 (HQ) July 26, 2005 10 0.3 

When a revised launch date was proposed to the Spaceflight Leadership Council in February, 

2005 for consideration, the briefing leading up to the decision only identified KSC processing 

timelines; no questions were asked regarding the ability of the elements to complete their 

work with adequate rigor in time to support this date; activities that were ongoing to support 

meeting the CAIB recommendations. Additionally, the debris/flight rationale requirements 

were discussed after the launch date was set, thereby never entering into the launch rationale. 

As we reviewed the path that NASA has taken to prepare for STS-114, it became apparent 

that there were numerous instances when an opportunity was missed to implement the best 

solution because of this false schedule pressure. Many times technical-level personnel 

indicated that if they had known that they were going to be grounded for 2 years, the solutions 

chosen would have been much different. The following examples illustrate how an unrealistic 

schedule for return-to-flight compromised standard processes: 

1. A decision was made not to install LO2 feedline bellows heaters on ET-120 (the 

first STS-114 tank) and ET-121 (the initial STS-121 tank, ultimately used on 

STS-114) despite evidence one might be required. Instead, only a relatively 

easy, but ultimately questionably effective, “drip lip” was installed on the first 

two tanks. Continued questions about its effectiveness eventually drove the 

program to roll-back STS-114 from the launch pad to install the heater. 

2. The implementation of the OBSS sensor package was selected before knowing 

the size of the damage that needed to be detected. In fact, as of July 11, 2005, 

the NSTS 60517, PRD for the Shuttle On-Orbit TPS Inspection System still had 

numerous TBDs for critical requirements regarding the required resolution 

capability. On several occasions, members of the NASA workforce have 

expressed that methods other than the OBSS would have been preferable and the 

OBSS was chosen due to the short time before the targeted launch date. 

3. The decision to stay with the STA-54 tile repair material was made on the 

apparent near-term availability of this material and not because anybody 

believed it was the best possible choice. 

4. Both Shuttle and ISS teams reworked flight manifests, schedules, and analysis 

many more times than should have been necessary due to this lack of an 

integrated approach to resolving the real issues and planning a realistic timeline 

to launch. This also resulted in repeated coordination with the international 

partners. 

True research and development (R&D) efforts – such as TPS repair – should not have been a 

constraint to the launch of STS-114 unless the Agency felt the capabilities to be provided by 

these R&D efforts were so important they could not risk lives without them. Additionally, 

NASA should have evaluated their return-to-flight activities and determined which efforts 

were not progressing as originally intended, then been completely honest with itself, higher 

authority, and the Task Group that they would not be able to meet those recommendations 

within the funding and schedule constraints imposed on the program. Schedules for R&D 

activities are difficult to predict, and perhaps should be the rationale to not include them as 

return-to-flight criteria. 

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Rigor Example 2 

On August 27, 2004, one year after the release of the CAIB report, the Space Shuttle Program 

signed PRCBD S062246 approving the Post-STS-107 Return-to-Flight Design Certification 

Review Plan and Procedures document, NSTS 60524. The proclaimed purpose of this 

document was to “define the activities and procedures for accomplishing the Space Shuttle 

Program (SSP) Design Certification Review (DCR) process for Return-to-Flight after the 

Columbia accident. This plan establishes the requirements, responsibilities, preliminary 

schedule, general implementation guidelines, and success criteria required to complete the 

post-STS-107 RTF DCR process and document the review results.” 

This document directed a tiered DCR process to formally demonstrate that new or modified 

systems, software, supporting processes, and operations meet the program design, safety, 

performance, and operational requirements levied upon the item in question. The process also 

required demonstration that “appropriate certifications have been performed” at lower levels. 

The document specifically recognized that the “tiered DCR process being conducted for RTF 

is not classical in nature as more content than simple certification of hardware is reviewed. 

The SSP is utilizing this process to cover other major topics, such as standard operational and 

process changes, which would otherwise be discussed at a Flight Readiness Review (FRR).” 

The design to be certified during the DCR was to include all changes occurring after the STS107 Certificate of Flight Readiness (CoFR) was signed on January 9, 2003. 

Ironically, the effect seems to have been largely the opposite. Instead of pulling FRR material 

forward into the DCRs, many of the projects/elements, and the program itself, stated during 

their DCRs that reviews of several activities would be deferred until the FRR. This seems too 

late in the process to be making critical decisions. 

In all, the 60-page document was an attempt to instill some discipline into the return-to-flight 

process. However, during fact finding, we noted that while a program-wide process for DCRs 

existed, it was not imposed on the various projects – each project and the Space Shuttle 

Program executed DCRs in different manners with wide variances in the scope, execution and 

rigor for the various project and system-level DCRs. In response to a question from a Task 

Group member on this wide variability, the Systems Engineering and Integration Office 

indicated they didn’t set any standard processes because MSFC and JSC operate differently – 

this from the organization that put together the DCR process originally. 

Additionally, a senior Space Shuttle Program official at one point denied the existence of a 

document governing the DCR process, despite the fact that he approved NSTS 60524. It is a 

concern that processes put in place specifically for the return-to-flight effort can be ignored so 

cavalierly without consequence. 

During early 2005, the program decided that since they would likely not be able to “certify” 

the debris aspects of the Space Shuttle system, the term Design Certification Review was no 

longer appropriate. Instead, a series of newly termed Design Verification Reviews (DVR) 

were held. These seemed to suffer a rough start; during the first DVR, when asked about the 

availability of data and documentation to support the review, the program responded that none 

was available. When asked about the success criteria for the review, the response from the 

program was that none had been established. Interestingly, NSTS 60524 was never updated to 

reflect the newly-coined DVR process. 

On one hand, the rigorous DCR process was ignored by many; on the other hand, there were 

too many of these reviews. Various parts of the program did not have all the necessary work 

completed in time for scheduled DCRs, so there ended up being multiple DCRs for each 

project/element to cover all the work. Rather than 12 System Reviews (6 DCRs and 6 DVRs – 

and none of these covered TPS repair), it likely would have been a better use of resources 

(particularly the reviewers’) to delay the System DCR/DVR until all the work was complete. 

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The degree of rigor employed during the return to flight effort has varied with the individual 

projects. At the one extreme are activities like the SRB Bolt Catcher redesign and, to a lesser 

extent, the modifications to the External Tank thermal protection system. Both of these 

projects exhibited a formal and documented approach to the establishment of requirements 

and execution of their design review and certification processes. Both the SRB Bolt Catcher 

and the ET had formal plans for their various reviews, formal data packages, a formal issue 

review process, formal pre-boards and boards, and well-documented formal findings. 

The other extreme includes activities such as Orbiter TPS repair, which have been extremely 

convoluted. While presentation material for the repair efforts was developed for the Orbiter 

DCR II held in February 2005, the material was not covered at that meeting. At the System 

DCR II later that month, it was stated that repair techniques would not be addressed in the 

DCR/DVR process, because there were no Level II requirements to have a repair capability. 

This was even though the DCR process was supposed to cover all changes since the STS-107 

CoFR, criteria that certainly applied to the repair techniques. 

Perhaps the most revealing behavior observed during the design reviews was at the Program 

DCR at KSC on April 19, 2005. This “review,” like many witnessed during the return-toflight effort, was not so much a review as it was a status briefing. No technical questions were 

asked by the Board; no technical responses given. With the single exception of the SSME 

Project, each project and element simply presented a high-level summary of their current 

status, including open work; SSME attempted to describe a technical problem and request 

help in resolving it, without much success. The final certification was conditional on the 

“satisfactory completion of identified open work,” but nobody before, during, or after the 

meeting kept track of the open work presented by the projects/elements. This meeting 

validated the CAIB observation of engineering and decisions via PowerPoint presentation 

rather than technical detail and rigor. 

Risk Example 1 

The Space Shuttle Program has, in the past, too often accepted risks that should have been 

mitigated; this trend appeared to continue during the return-to-flight effort. It appears to us 

that what the CAIB wrote (Vol. I, p. 193, F7.4-5) is still applicable today: “Risk information 

and data from hazard analyses are not communicated effectively to the risk assessment and 

mission assurance processes. The Board could not find adequate application of a process, 

database, or metric analysis tool that took an integrated, systemic view of the entire Space 

Shuttle system.” 

Ultimately, few programmatic responsibilities are more important than identifying and 

assessing risk and determining if it is acceptable from both a cumulative and integrated 

perspective. As the Space Shuttle became “operational,” NASA did not sustain the risk 

identification, assessment, management capabilities, or mindset required for what in reality 

was a developmental vehicle operating in a high-risk environment. Prior flight history became 

an accepted risk rationale. The perceived risk level during the launch of STS-107 was not 

aligned with the facts regarding the actual debris environment, just as the perceived risk for 

Challenger had not been aligned with the true state of the o-rings. Nevertheless, the issues 

were considered accepted risks that had potentially catastrophic consequences, but with a 

remote likelihood of occurrence. Despite this perception, in reality the risks should have been 

considered unacceptable – potentially catastrophic consequences with a good likelihood of 

occurrence. 

This should have initiated a design change, either to eliminate the debris environment or to 

modify the Orbiter to withstand the resulting debris environment, in accordance with the 

Space Shuttle Hazard Reduction Precedence Sequence (NSTS 5300.4[1D-2] Section 1D201, 

Item 6, based on MIL-STD-882D, Section 4.4). This program-wide policy has as its first step, 

design action to eliminate the hazard: 

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Hazard Reduction Precedence Sequence. To eliminate or control hazards, the contractor 

shall use as a minimum the following sequence or combination of items: 

a. Design for Minimum Hazard. The major goal throughout the design phase shall 

be to ensure inherent safety through the selection of appropriate design features 

as fail operational/fail safe combinations and appropriate safety factors. 

Hazards shall be eliminated by design where possible. Damage control, 

containment and isolation of potential hazards shall be included in design 

considerations. 

b. Safety Devices. Known hazards which cannot be eliminated through design 

selection shall be reduced to an acceptable level through the use of appropriate 

safety devices as part of the system, subsystem, or equipment. 

c. Warning Devices. Where it is not possible to preclude the existence or 

occurrence of a known hazard, devices shall be employed for the timely 

detection of the condition and the generation of an adequate warning signal. 

Warning signals and their application shall be designed to minimize the 

probability of wrong signals or of improper personnel reaction to the signal. 

d. Special Procedures. Where it is not possible to reduce the magnitude of existing 

or potential hazard through design, or the use of safety and warning devices, 

special procedures shall be developed to counter hazardous conditions for 

enhancement of ground and flight crew safety. Precautionary notations shall be 

standardized. 

It is recognized that any design change takes time to develop, implement, and certify; 

however, the specific design action could be underway while the program assesses the 

technical risk of continuing operations and maintains a focused awareness of the risk in each 

area. The program should not have the option of short-circuiting the process by skipping to 

“accepted risk” as was done before both Challenger and Columbia. 

The goal is to change the design to completely eliminate the risk. As with all design actions – 

especially when dealing with high technology programs such as spaceflight – it is recognized 

that there will be limitations driven by the laws of physics and program resources. The Space 

Shuttle has a finite life (scheduled to be retired in 2010) and no program has, or will have, 

infinite resources. The best available technical solution should be sought without regard to 

schedule and resources limitations; these will come into play when the proposal is formally 

brought before program management (i.e., the PRCB). The modification should be installed at 

the earliest opportunity to remove the risk; however, in the interim, procedural mitigations 

could be used to minimize the risk of continuing to fly if an acceptable-risk rationale can be 

developed. This is the approach we expected to see in the Integrated Risk Acceptance 

Approach For Return To Flight, but did not. 

Every risk (non-conformance) should be documented, have a documented rationale for 

limited acceptance, and a documented risk retirement plan with the objective of completely 

eliminating the risk. Again, it may not be feasible to retire all risk, but it is important for 

NASA to develop an understanding of what is involved in the resolution of non-conformances 

and the retirement of risk. 

We do not feel that the program is currently using this process to mitigate or accept risks. For 

example, it took the current NASA Administrator’s personal intervention during a technical 

review held shortly after his appointment to force appropriate recognition by program 

management that the well known and recognized ice shedding from the External Tank was, in 

fact, potential critical debris and should be treated as such. His further direction finally forced 

the slip of STS-114 to the July 2005 launch window in order to incorporate necessary 

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technical control measures (i.e., the forward LO2 feedline bellows heater). Absent the 

Administrator’s direct action, STS-114 might very well have launched with the physical cause 

of Columbia’s loss (ET bipod ramp foam) fixed, but with an identified, yet unacknowledged, 

risk to vehicle and crew. 

NASA should return to compliance with its long-established procedures for addressing risks. 

There are enough risks in the “unknown-unknowns” without unnecessarily increasing risk by 

not promptly and rigorously resolving the “known-knowns” and “known-unknowns.” 

Risk Example 2 

We do not believe the risk assessment processes in place within the Space Shuttle Program 

are sufficiently robust. One telling sign is the program’s development of a document entitled, 

The Integrated Risk Acceptance Approach For Return To Flight, which the Space Shuttle 

Program points to as a response to inquiries regarding risk assessment and risk management. 

The document appears to be intended for the uninitiated reader rather than a being a technical 

document for use by the program. 

The main text of the May 2005 version consists of 41 pages that are essentially a chronology 

of events leading to the current state written more for a general primer than a serious treatise 

on institutional process and rigor necessary for consistent, successful risk management. The 

Residual Risk Matrix contained in an additional 18 pages of Appendix A lists remaining tasks 

or “Objectives” rather than identified areas of risk. The remaining three columns delineating 

“Evidence of Objective Completion,” “Remaining Risk,” and “Acceptance Rationale,” in 

order are populated by items which are frequently vague and require considerable suspension 

of belief to conclude a particular risk acceptable. As an example, under “Remaining Risk” on 

page A-3 the last item states: 

“Although these efforts will in all likelihood reduce the potential for flow of liquid 

nitrogen through the flange and reduce the potential for foam loss in flight, there is 

no quantitative means to demonstrate this as fact. Previous foam divot formation in 

the flange area produced foam debris below the current allowable. NASA has 

considered and accepted this risk.” 

The corresponding “Acceptance Rationale” states simply, and somewhat glibly, “Acceptable 

Risk.” Unfortunately, this raises more questions than it answers, such as: 

How does one conclude reduction, “...in all likelihood...”? 

What “...previous foam divot formation...”? Flight? Ground Test? 

What is “...the current allowable...”? 

How was “...allowable.” determined? 

Finally, how did NASA consider and accept the risk? As a follow on, what is the plan to 

reassess or correct if existing risks are accepted? 

Requirements Example 1 

The NSTS 07700 (the top-level specification for the program) requirements are substandard 

in a number of areas: they are not individually numbered to facilitate referencing an 

individual requirement (i.e., there are multiple “shalls” per paragraph); they are often stated in 

an ambiguous and untestable fashion; and there is inconsistent use of terminology such as 

“shall,” “will,” and “must.” Given the 2010 retirement of the Space Shuttle, it does not make 

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sense to go back and correct existing requirements; however, those requirements modified or 

added as part of the return to flight effort and any subsequent requirements changes should 

adhere to industry-standard requirements practices. This includes documenting the 

verification and validation criteria at the same time as the requirement (before implementation 

begins), a practice not in evidence in the requirements documents made available to the RTF 

TG. Additionally, on multiple occasions the Task Group asked about the ability to have an 

auditable trail from Level II (NSTS 07700) requirements and directives down to the 

implementing actions on the floor. The Task Group was informed that the Program 

Configuration Management System did not allow for such an auditable trail. 

Nor does the program seem to know how to change requirements. For example, there is a 

requirement in NSTS 07700 for zero debris “that would jeopardize the flight crew, vehicle, 

mission success, or would adversely impact turnaround operations” (Book X, 3.2.1.2.14). 

After it was determined that the External Tank would continue shedding debris of a 

potentially critical size, the program decided – after 113 flights – they needed to change or 

waive the requirement. The first change was to add a requirement that the External Tank 

could not shed debris that generated impacts larger than 1,500-ft/lbs (NSTS 07700, Book X, 

3.2.1.2.14.4.1). This requirement later turned out to be inadequate since the Orbiter could not 

be certified to withstand impacts that large. In response, a permanent waiver to this Level II 

requirement was proposed stating “This requirement is waived for the External Tank.” 

However, this generated controversy within the program and an alternate proposal was 

brought forward to eliminate the need for any debris waivers by adding an “exception” (see 

Requirements 2) to the top-level NSTS 07700 requirement. The Task Group does not know 

the status of either proposal since the PRCB does not publish minutes of their meetings. As 

late as the second Program DCR (June 2005), program management was attempting to 

establish the mechanism for documenting requirements and exceptions; by this time the 

hardware was on the pad. 

Requirements Example 2 

How do you meaningfully track requirements when you do not understand the definitions of 

programmatic terms? For instance, at the STS-114 Flight Readiness Review, the Space 

Shuttle Program attempted to define the terms “Waiver,” “Deviation” and “Exception.” 

Within the documentation listed, there were 11 definitions for “Waiver,” 7 for “Deviation,” 

and 5 for “Exception;” some definitions were combinations of the terms. Sometimes there 

were multiple definitions for a single term with in one volume of NSTS 07700 – and even 

worse, sometimes within the same paragraph of NSTS 08171! 

Standard definitions for many engineering terms exist in industry and academia; NASA 

should adopt these standard definitions wherever possible and use them consistently. For 

instance, like the CAIB, the Task Group found that the “in-family/out-of-family” designators 

a continuing source of confusion. Unfortunately, NASA seems to place a low priority on 

maintaining standard terms and definitions. The following entry was found in a list of NASA 

Handbooks at Headquarters: “NHB 5300.4(1G) NASA Assurance Terms and Definitions – 

Has been deleted – Long term plans call for development of a NASA-Standard for 

definitions.” We have no idea when these “long-range plans” will come to fruition. 

Models Example 1 

NASA has in the past maintained certain models in formal requirements documents (e.g., 

NSTS 07700) and employed well-recognized processes for developing and using analytical 

models. However, during the return-to-flight effort, there has been an enormous expenditure 

of time and resources – amounting to tens of millions of dollars – without the discipline of a 

formal development plan, clear objectives, explicit plans for verification and validation, 

thorough outside review, documented ICDs between models, or a good understanding of the 

limitations of analytical systems employing multiple, linked deterministic models. Validation 

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and verification planning has been left to the end of the process rather than the beginning. 

Early peer reviews were limited to the question of appropriateness for the proposed task and 

never reassessed or reconstructed post-development. Even the belated efforts by the NESC are 

not classic peer reviews. Outside peer reviews would highlight, for example, the extreme 

difficulty, if not impossibility, of forming an end-to-end conclusion on the confidence interval 

inherent in any particular result. Even more troubling, in many instances historical flight data 

was not used during the initial stages of model development. 

On several occasions, members from the NESC and RTF TG expressed concern regarding the 

development and use of debris models. We observed that development test data was being 

used rather than verification test data in attempts to verify models. It should be noted that the 

development test data was obtained over widely varying test conditions. Analytical models 

have essentially driven the return-to-flight effort; however, industry and academic standards 

and methods for developing, verifying, and validating the models have not been used. In 

addition, no sensitivity analyses had been conducted and no empirical data from flight history 

had been incorporated in the models or their validation. Suggestions to use flight history, 

probabilistic techniques, and sensitivity analysis were disregarded. A formal request for a 

stand-down to evaluate the completed works was ignored. 

All the while, the External Tank was being modified to meet requirements established by 

preliminary and interim model outputs. In December 2004, a modified External Tank meeting 

these interim requirements was shipped to the Kennedy Space Center with the understanding 

that if the final requirements determined by the modeling effort resulted in smaller debris 

allowables, the next tank in line would be modified to meet the more stringent requirements, a 

so called “trailing tank” concept. For various reasons, the program decided to abandon the 

trailing tank concept before the second tank was shipped to the Kennedy Space Center. 

Models Example 2 

Progress has been made by the ET Project to reduce the risk of critical debris during ascent. 

Many of these changes were made on the basis of debris-flow modeling and transport 

analysis. Initial analysis and simulation of the Orbiter showed that the RCC could withstand 

impacts up to 1,500-foot-pounds, a figure that was turned into a requirement for the ET 

Project. The tools that produced these initial estimates had not been verified or validated, yet 

their output was used to develop and build flight hardware. Further impact testing of actual 

RCC, however, showed that 1,500-foot-pounds are far greater than the RCC can actually 

withstand reliably. This knowledge came too late, and the ET Project had already modified 

External Tanks based on the original 1,500-foot-pound number. 

In an attempt to justify both numbers – the larger number given to the ET Project and the 

lower number for the Orbiter Project – a complex effort was undertaken to develop a 

Capability over Environment (C/E) analysis, using several of the models already being 

developed. In this case, the “capability” is the size and speed of impact the Orbiter can 

withstand, while the “environment” is the amount of debris coming off the External Tank (and 

other sources). Numerically, a value of “1.0” implies the hardware can withstand the 

environment – but just. Normally a factor of safety, often “1.4” in the Space Shuttle Program, 

is required for additional margin. 

The C/E approach was first introduced to the RTF Task Group during the September 2004 

Plenary. The program provided the results of the initial assessment that indicated critical 

debris was a particular size, but admitted that the uncertainties were several orders of 

magnitude on either side. On February 17, 2005, the then-current C/E analysis was presented 

to the program; in almost all cases the C/E was less than 1.0, meaning that the capability of 

the Orbiter to withstand damage was less than the amount of debris in its expected flight 

environment. This analysis had been done using “worst-on-worst” conditions corresponding 

to certification levels; something everybody agreed was unlikely to occur in real life, but in 

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Standard “4 by 3” 

risk chart used by 

the Space Shuttle 

Program. 

accordance with the ground rules laid out when the C/E analysis began. The next day, at the 

Spaceflight Leadership Council meeting, it was presented that if the worst-on-worst C/E was 

less than 1.0, the program would look at best-estimate C/E. 

It should be noted that determining exactly what factor of safety was provided by the models 

is a bit challenging. For instance, each of the component models in the C/E worst-on-worst 

analysis had a factor of safety of 1.4 built into it, therefore a combined C/E of 1.0 in reality 

still had an adequate factor of safety. This became more problematic with the “best-estimate” 

analysis, where estimates of more likely performance (for both the Orbiter and the External 

Tank) were used. Keeping track of the ever-changing differences in inputs between worst-onworst C/E and best-estimate C/E was difficult; there was little agreement in the community on 

what factors should be included in the best-estimate version. 

At the beginning of the Delta Design Verification Review (April 26-27, 2005), the rules stated 

that if the “best-estimate” of Orbiter capability relative to debris environment (C/E) was less 

than 1.5, then the likelihood on the standard program 4x3 risk matrix would be “infrequent,” 

and if 1.5 or greater it would be categorized as 

“remote.” For example, for the LO2 intertank 

flange closeout, the best-estimate C/E was 1.1, 

which should have classified the risk as 

“infrequent.” However, many argued that the 

problem was sufficiently well understood that 

it could be put in the “remote” category 

despite its low best-estimate C/E. Others said 

it should be “infrequent” since that is what the 

process dictated, and that it involved “old” 

foam and therefore contained a greater uncertainty. At that point, Space Shuttle Program 

management pronounced that the best-estimate C/E value of 1.5 determining an “infrequent” 

vs. “remote” rating was only a guideline, not a rule. The middle of a design review does not 

seem an appropriate time to be changing the rules. 

The arbitrary nature of the requirements/fulfillment process is demonstrated by the February 

2005 changes in approach (from “worst-on-worst” to “best estimate”) and reduction in factors 

of safety to make the numbers come out right. When asked during the RTF TG March 2005 

Plenary if the tank will change when results from the modeling are finally available, the 

answer was “... no, that’s why we’re changing the models so we don’t have to change the 

tank.” 

The program continued to develop and make decisions on analysis techniques, such as bestestimate C/E, which used non-standard approaches. This history of the C/E logic raises 

questions regarding the management of the return-to-flight effort. Fortunately, this approach 

was abandoned when the Program reluctantly initiated probabilistic analyses on additional 

critical areas at the direction of the new Administrator. Analytical models have essentially 

driven (and delayed) the return-to-flight effort even though industry and academic standards 

and methods for developing, verifying, and validating the models have not been used. 

Models Example 3 

During the reviews of the probabilistic analysis efforts, requests were made by several people, 

including Task Group members, to clearly state the assumptions going into these models. It 

was not until the end of the 6-week review effort that the assumptions to some of the models 

used for this activity were recorded; for some of the models, no comprehensive set of 

assumptions were ever documented. By their nature, these models are complex and 

sophisticated analysis tools. Therefore, the quality of the original assumptions is important; 

they should be written down and consistently applied. 

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Leadership Example 1 

A clear example of a lack of budgetary restraint was demonstrated by the management of the 

TPS repair projects. For an extended period of time, there were few constraints placed on the 

development teams, and money was spent on the development of almost any idea that was 

proposed. Only when the large-scale RCC rigid overwrap repair effort was finally deemed 

untenable was it removed from the list of options being considered for STS-114. At the 

direction of the Space Shuttle Program, during late 2004 the Orbiter Project Office initiated a 

study to eliminate some of the repair options in an attempt to focus manpower and budget on 

the most promising techniques. This resulted in resources being expended to generate 

proposals, and an evaluation team worked over the winter holidays to develop a 

recommendation on which options to select. Ultimately the Orbiter Project Office brought 

forward two tile repair options and a single RCC repair option to Space Shuttle Program 

management. Nevertheless, six options (two for tile repair and four for RCC repair) were 

actually considered by the program, and only one RCC option was ultimately dropped. 

Surprisingly, although a stated reason for performing the down-select was to reduce 

expenditures, cost estimates were explicitly excluded from the factors used in the decision. 

Several months later, when two cost Change Requests (CR) for continued tile and RCC repair 

development were brought to the PRCB (asking for nearly $100M for the last 5 months of 

FY05), the CR sponsor objected to suggestions that the program needed to consider if this 

was how limited resources should be spent. In the end, the only criteria that determined how 

much would be spent on the two CRs was whether all the money could be spent by the end of 

the fiscal year, not whether this was a wise use of limited program resources. 

A.3 Observations by Mr. Joseph W. Cuzzupoli and Mr. Richard H. Kohrs 

NASA’s aggressive future plans require experienced personnel from both government and 

government contractors. To meet the challenges ahead for the U.S. Space Program, NASA 

would be wise to bring back experienced, ex-NASA employees with development 

engineering expertise to fill the many holes left in the Agency. 

The utilization of operational-type management and engineers made the return to flight of the 

Space Shuttle difficult. Nevertheless, the result was enormously positive for NASA. They got 

there! We are proud of the NASA management and engineering teams for this most 

successful accomplishment. 

A.4 Observations by Dr. Charles C. Daniel 

When performing a post accident investigation, it is of primary importance to be able to 

establish the “root cause “of the failure condition. In the case of the Columbia accident, the 

physical cause was isolated by the CAIB to a release of foam from the bipod ramp of the 

External Tank. However, the exact release mechanism (root cause) for the foam was never 

successfully replicated. The ET Project decided to remove the bipod ramp foam, thus 

eliminating the potential for this specific release; this action did not, however, address the 

release mechanism of other areas of thermal protection system foam applied using similar 

processes. The ET Project established the adhesive/cohesive mechanism as the “most 

probable” failure mode for producing debris release. All of the design and process changes 

implemented were intended to reduce the risk associated with the adhesive/cohesive failure 

mode. Although other failure modes were identified, they were not the focus of the return to 

flight activity. The assumption was made that these failure modes had not occurred on prior 

flights, and therefore would not in the future. Unless the specific failure root cause can be 

established and eliminated, all failure modes must be addressed and closed out. 

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A.5 Observations by Ms. Susan Morrisey Livingstone 

The RTF TG Charter focused specifically on the 15 CAIB return-to-flight recommendations. 

With respect to these 15 recommendations, many NASA residual issues and planned future 

actions remain. In addition, the CAIB had 14 other recommendations, as well as numerous 

other important findings and observations. The NASA Implementation Plan further added yet 

other “raise the bar” actions. Finally, NASA determined that the CAIB report had many 

valuable “lessons learned” applicable to the agency as a whole. NASA needs to capture and 

integrate these lessons learned and planned future actions and determine how they will 

effectively monitor fulfillment and/or reassess and adjust them. 

In terms of the specific CAIB RTF recommendations, I offer the following additional 

supplementary observations. 

1. R3.4-1, 3.4-1, 3.4-3, 6.4-1: In highly complex systems, integration of multiple sources of 

data and the translation of such data into meaningful forms that support decision making 

remain a critical, but challenging requirement, particularly in making time sensitive, 

integrated risk vs. risk trades. Upon RTF of the Shuttle, this is particularly true given the 

enhanced imagery, inspection, and potential repair capabilities post-Columbia. NASA’s 

refinements in its Shuttle risk mitigation and risk management approach, to include the 

future of CSCS/LON, are critical parts of this integrated process. The Space Shuttle 

Program’s development of the OIP/Annex (see section 2.2 of this report) represents 

significant forward progress in providing a framework for such integration, as well as 

providing an integrated risk vs. risk methodology. Continued flight-to-flight verification 

of and refinement in these documents can serve as an important metric of post-RTF 

progress in these areas. Over time, NASA decisions to retain and further improve 

required performance or resolution enhancements in Shuttle imagery and inspection (e.g., 

LDRI and post-OBSS), along with the continued development and training of the thermal 

Protection System Management Working Group and Mission Management Team in their 

use, might also be good metrics to track. 

2. R3.4-1: To fully ensure Mission Management Team pre-launch evaluation of the R3.4-1 

assets, NASA might wish to consider defining minimum requirements for them in the 

Operations and Maintenance Requirements System Document, rather than the Kennedy 

Space Center Program Requirements Document. 

3. R4.2-3: I strongly recommend continued NASA attention to strengthening its quality 

assurance program. The work of the Government Mandatory Inspection Point 

Independent (GMIP) Assessment Team and their January 22, 2004, Independent 

Assessment Final Report provides a good beginning. This CAIB recommendation 

combined with R4.2-5 more than clearly underscored the important need for clarity and 

standardization of processes, standards, and terminology within and between NASA 

elements and programs. 

4. R6.2-1: Pressure for under budgeting and overly aggressive scheduling must be 

recognized and mitigated by senior leadership. As a significant part of this effort, NASA 

needs to address the required size and capability mix of its future workforce, to include 

commensurate leadership and managerial capabilities. Since the most critical part of 

“resources” is human capital, NASA faces a challenge in terms of addressing the skills 

and talents (in-house and outsourced) required to successfully fulfill the Space Shuttle 

Program and transition to the Vision for Space Exploration. As the CAIB noted, the 

Space Shuttle was being treated as an “operational” instead of a “developmental” 

program, and over time, NASA management and workforce was skilled accordingly. 

Based on the Agency’s experience in the return-to-flight effort, NASA will need to 

determine the extent that management and engineering skill sets and processes required 

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of a developmental program have atrophied or been lost and the corrective action needed. 

Such an assessment also needs to address the contractor workforce, to include 

supervisory chains to ensure appropriate direct NASA leadership and managerial 

oversight of critical work functions. 

5. R6.3-1: While our Final Report addresses forward work for the Shuttle MMT, necessary 

coordination between the Space Shuttle Program and the International Space Station 

(ISS) Program remain another “work in progress”. The primary mission of the Space 

Shuttle is to complete assembly and provide logistical support to the ISS. Given this fact, 

it is imperative that effective communication and integration occurs between these two 

organizations. Frequently, pre-flight decisions made by the SSP have an impact on 

planning by the ISSP. Similarly, ISS issues have a direct bearing on SSP operations. 

Although the JPRCB exists to manage this process, NASA needs to determine if it 

adequately provides the overall integration that needs to occur. Additionally, during realtime mission operations, significant coordination and discussion are required among the 

two flight control and mission management teams relative to anomalies with the Orbiter 

that may affect current and future ISS operations and vice versa. During RTF TG 

observations of MMT simulations, fully effective demonstration of this needed SSP-ISS 

integration activity was not clear. Indeed, for most of the Shuttle MMT simulations over 

the past 2 years, limited involvement by the ISS Program in the MMT simulation training 

was evident. Future MMT training events need to fully exercise and reinforce the 

importance of an integrated Station-Shuttle mindset. 

6. R6.4-1: Given post-RTF remaining work on debris reduction, Orbiter hardening, and 

repair techniques, NASA will need an effective plan for prioritizing such work. At a 

minimum, NASA will need to analyze the costs and benefits (to include risk reduction 

value) of planned future work – and the trades within and between – for further ET debris 

liberation reduction work, further Orbiter hardening phases, and additional work to 

mature tile and RCC repair capabilities. As a part of this analysis, objective success 

criteria for each should be established along with requirements for verification, validation 

and certification. Peer review in this analysis would be helpful, particularly in 

determining potential impacts on flight accepted risk rationale from an STS-114 baseline. 

7. R10.3-1: NASA should determine if use of the full capability of the standardized, high 

resolution cameras would be beneficial for close-out photography. 

A.6 Observations by Mr. James D. Lloyd, ex-officio 

Over the past two years of the RTF TG charter, I believe we have witnessed the coalescence 

of an entire Agency around a single goal in a crises caused by a catastrophic accident that 

killed seven members of the NASA family and destroyed a national resource. Since the 

Columbia accident, NASA has consistently placed safety above regard for cost or schedule in 

our efforts to return the high-performance, yet fragile, Space Shuttle system to flight. At the 

same time, NASA has begun phasing out the Space Shuttle which is scheduled to complete its 

mission of assembling the International Space Station in 2010. 

There are a number of behaviors that stem from NASA’s core values of safety, integrity, 

excellence, and care for the NASA family. Attention to detail is one of the most important. 

This is a trait demanded from the “touch” labor force and technicians when dealing directly 

with aerospace flight hardware; unfortunately, we had to re-learn that it is also required of 

engineers and managers at other levels of the organization. We must continually remind 

ourselves that human space flight is hard, expensive, and risky. But it is worth doing. 

It is likely that as we fly more missions that are successful on the Space Shuttle, there will be 

a temptation to reduce the funding for the Program which could lead to a relaxation in our 

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engineering rigor. At first, it will be fairly easy to deflect these urges to economize by 

pointing to the CAIB report. We must remain vigilant to prevent success from breeding 

complacency, and then failure. This progression is a well-documented phenomenon that is 

repeated for almost any complex system. Today’s strong stance against cutting resources for 

operating successful programs will almost certainly regress. Because of NASA’s “can do” 

spirit, we will likely take on the challenges of fewer resources and constrained schedules to 

meet the goals set for us by our leaders. NASA needs to guard against shortchanging the 

processes that will help us to identify and prevent the next accident. To ensure that we do not 

repeat our past mistakes, we must continue to capture the knowledge that we gain and 

overcome the obstacles presented by problems we encounter as we operate and eventually 

complete the mission of the Space Shuttle. The challenge for NASA and our stakeholders in 

the Space Shuttle Program is to understand the paradox that success will breed new 

challenges and to be wise enough to know that we cannot perform human space flight “on the 

cheap.” This same approach will apply as much to the crew exploration vehicle now being 

conceived. 

With a management team humbled by failure, with a new philosophy for independent 

technical authority (ITA), with a substantial new capability to perform in-depth and 

independent engineering test and analysis (the NASA Engineering and Safety Center), with a 

refortified safety and mission assurance organization, with a new energy and focus for system 

engineering, and with an Aerospace Safety Advisory Panel ready to receive the “battle flag” 

from the Return To Flight Task Group, we believe we already have, or are building in, the 

right amount of tension to counter any significant back-sliding for the next several years. This 

combination of management wisdom and independent thinking may keep us from collectively 

falling back into the dangerous “group think” posture that the CAIB described. We need to 

continue both an environment for healthy dialog and a culture of dissent for each present and 

future program. If we are able to preserve the combination of NASA’s can-do attitude and an 

unflagging attention to the engineering details, we will be able to fulfill the vision for 

exploration while successfully completing the tasks assigned to the Space Shuttle Program. 

A.7 Observations by Lt. Gen. Forrest S. McCartney 

Recovery from a major aerospace accident is always a very painful experience, especially if 

human life is lost. The personnel involved in the investigation and oversight of the recovery 

should be carefully chosen and have experience in related activities (such as aircraft, space 

hardware development, weapons systems development, space operations, underwater naval 

activities. etc). The accident investigation report should be carefully written and focused on 

the root cause of the accident, since the recovery team normally reacts to the 

recommendations in a very aggressive way (which was certainly the case for the Columbia 

accident). Any oversight group (such as the RTF TG) has the responsibility to evaluate the 

recovery team’s efforts from a very difficult viewpoint. A phrase sometimes used is “to call 

balls and strikes” or, said another way, to focus on the results of the recovery team’s actions – 

not the motions of the recovery team in implementing their recovery actions. 

While some of us might have approached the recovery process in a different way, the end 

result is what counts. In my opinion, The NASA Headquarters leadership and Space Shuttle 

Program Office have done their best to implement the actions they believe will lead to a safe 

return to flight. The entire Space Shuttle work force is dedicated to accomplishing the work 

necessary for safely returning to flight. They are to be congratulated on their efforts. 

A.8 Observations by Dr. Rosemary O’Leary 

The CAIB criticized NASA for an organization culture that tends to suppress dissent. Indeed, 

the issue of how NASA managers handle dissent within the organization permeated many of 

the RTF TG items presented in this report. To be more specific, the more significant challenge 

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facing NASA is a form of dissent suppression called “groupthink.” Groupthink is an insular 

decision-making process in which decision makers are so wedded to the same assumptions 

and beliefs, that they ignore, discount, or even ridicule information to the contrary (Janis 

1972). Symptoms of groupthink include overestimations of the group’s power and morality, 

closed-mindedness, and pressure toward uniformity. 

As former NASA Administrator Sean O’Keefe put it, the biggest battles at NASA are not 

between the Agency and Congress, as some might think. They’re between and among the 

diverse disciplinary groups who work in parallel “silos.” Sometimes diverse opinions and 

judgments are crushed or shouted down, but they are more often automatically deemed 

improbable or ignored. The dismissing of other viewpoints happens so quickly and is 

sometimes so subtle that as a leader it is very tough to address. 

The opinions and judgments developed by individual teams often follow a different logic path 

than other teams. Hence, when another viewpoint is expressed by an “outsider” or someone 

questions the result, NASA employees often dismiss the opinions offered because they don’t 

take the time to understand the rationale or path taken. More troublesome, as the Integrated 

Vehicle Assessment Sub-Panel observed during fact-finding on March 30, 2005, sometimes 

the parallel silos are so poorly integrated that no discussion or connection ensues. Even worse 

is what the task group discussed at that same meeting: “malicious compliance” where lip 

service is given to gathering different viewpoints and analyses, yet it is not done in reality. 

Despite these challenges, many NASA employees at all levels are quick to dismiss the 

importance of an improved organization culture and the need for organizational change. Thus, 

one of the problems facing the new NASA Administrator, Mike Griffin, is how to change the 

culture of the Agency from one of malicious compliance, parallel silos, and lack of horizontal 

communication where different ideas are quickly dismissed, to one that embraces a diversity 

of views and uses those differing viewpoints for constructive change. 

My work as a member of the RTF TG over the last two years coincided serendipitously with 

the writing of my forthcoming book on dissent in organizations (O’Leary, 2006). As a part of 

this effort, in 2005, I surveyed some members of the RTF TG, members of the National 

Academy of Public Administration (NAPA – an independent, non-partisan organization 

chartered by Congress to assist federal, state, and local governments in improving their 

effectiveness, efficiency, and accountability), and alumni of the Maxwell School of Syracuse 

University (the oldest – and top ranked – school of public affairs in the country). I asked them 

about the value of dissent in organizations, but more importantly how to manage dissent. Of 

the 216 current and former managers who responded, 213 indicated that dissent, when 

managed properly, was not only positive, but essential to a healthy organization. 

From these 216 surveys came dozens of suggestions for how to manage dissent and how to 

address groupthink in NASA. I present some of them here with the hope of furthering the 

discussion about dissent at NASA: 

1. Embrace dissent. This means inviting a diversity of opinion from the people 

around you. Never surround yourself with people who are just like you. 

2. Always insist upon someone voicing the dissenting opinion. Always. 

3. Create an organization culture that accepts, welcomes, and encourages candid 

dialogue and debate. Cultivate a questioning attitude by encouraging staff to 

challenge the assumptions and actions of the organization. 

4. Set up a regular process to receive dissent. Be accessible. Have an open door 

policy. Insist that employees come to you first. Allow employees to dissent in 

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civil discourse in group meetings or in private through memos or conversations: 

some people who have great ideas that challenge the status quo do not like to 

publicly display them. 

5. Implement two-way evaluations where managers evaluate employees and 

employees evaluate managers. Managers who are involved in groupthink do so 

without realizing it. Often times lower level employees can see it, label it, and 

draw attention to it. 

6. Make available options for addressing all types of problems to all people in the 

workplace, including employees, supervisors, professionals, and managers. A 

systemic structure that coordinates and supports multiple access points and 

multiple options and integrates effective conflict management practices into 

daily organizational operations should be provided. Persons who are 

knowledgeable and trustworthy for approaching with advice about a conflict or 

the system should be easily identified. 

7. Encourage the resolution of conflict and collaborative problem solving at the 

lowest level through direct discussion and negotiation. 

8. Listen. The hallmark of a strong leader is to be a good listener. Don’t just hear 

the dissent, but to probe it, evaluate it, challenge the underpinnings (without 

discarding it out of hand), and make a reasoned decision on whether the dissent 

has a viable position. 

9. Understand the formal and the informal organizations. The informal 

organization, generally, is that which may not manifest itself on an organization 

chart or in official documents. Examples include histories and connections 

between and among employees, traditions, power bases, and how the 

organization has learned to cope with challenges. The informal organization 

may be more difficult to identify than the formal, but it is often the environment 

within which dissent grows and develops. 

10. Separate the people from the problem. Approach the issues on the merits and 

people as human beings. Fisher, Ury and Patton (1991) reinforce this in their 

best selling book Getting to Yes where they advise to separate the relationship 

from the substance, deal directly with the people problem, and strive to solve 

collaboratively the problem at hand. 

11. Use peer review. Experts such as the National Science Foundation, NAPA, 

FACA committees, consultants, and university professors can help sort out the 

diversity of analyses and opinions that naturally arise from a healthy 

organization. 

12. Allow the process that encourages diversity views enough time to fully run its 

course, but create dissent boundaries and know when to stop. Dissent is 

important, but a leader has to know when to say “enough.” Then sit down with 

staff and explain how and why you made your decision. 

Dissent exists in every organization to some degree. The point is to create and promote a 

workplace climate in which dissent is constructively addressed and resolved, and groupthink 

is kept in check. NASA needs to learn how to tap into the potentially insightful, creative ideas 

and energy of dissenters: They may be canaries in the coal mine telling the leaders that 

something is awry. 

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These ideas of those I surveyed are in keeping with much of the classic and current literature 

in organization theory and management. Slater and Bennis (2003), for example, espouse more 

democratic organizations that have the following characteristics: 

• Full and free communication, regardless of rank and power. 

• A reliance on consensus, rather than the more customary forms of coercion or 

compromise to manage conflict. 

• The idea that influence is based on technical competence and knowledge rather 

than on the vagaries of personal whims or prerogatives of power. 

• An atmosphere that permits and even encourages emotional expression as well 

as task-oriented acts. 

• A basically human bias, one that accepts the inevitability of conflict between the 

organization and the individual, but which is willing to cope with and mediate 

this conflict on rational grounds. 

A NASA organization culture that counteracts groupthink by welcoming “diversity thinking” 

is essential. Kingdon (2003: p. 183) sees the “free-form process” triggered by diversity 

thinking as promoting creativity and an opportunity for new and innovative ideas to emerge. 

Diversity thinking yields entrepreneurs who often act as brokers, negotiating among people, 

yielding couplings that might never have occurred in a more structured setting. These 

couplings, or linkages of workers outside their immediate workgroups, often yield new ideas 

(Erard, 2004). 

Scholars who have empirically studied career public servants routinely find that they are 

largely highly principled, hard working, responsive, and functioning professionals. NASA is 

no exception. If NASA can continue to work on improving its organization culture to embrace 

dissent and banish groupthink, it has a fighting chance of remaining one of our premier public 

organizations. 

References 

Erard, M. “Where to Get a Good Idea: Steal It Outside Your Group.” The New York Times, Sec. B., Col. 1: 9 

(May 22, 2004). 

Fisher, R., W. Ury and B. Patton (1991). Getting to Yes. New York: Penguin. 

Janis, I (1972). Victims of Groupthink. Boston: Houghton Mifflin. 

Kingdon, J. W. (2003). Agendas, Alternatives, and Public Policies. New York: Longman. 

O’Leary, R. (forthcoming January 1, 2006). The Ethics of Dissent: Managing Guerrilla Government. 

Washington, D.C.:Congressional Quarterly. 

A.9 Observations by Mr. Seymour Z. Rubenstein 

During the recovery from the Columbia accident, it was apparent that NASA was going to 

require a significant number of development engineers to accomplish the recommendations of 

the CAIB. The dominant makeup of the technical force was test, and flight and ground 

operations personnel. This is true at NASA and its major contractors. During the investigation 

period, a great deal of help was derived from “the graybeards.” However, when it came time 

to develop the fixes, systems engineers, development engineers, manufacturing engineers, and 

contractors with development experience were in short supply. As a result, some of the work 

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Final Report of the Return to Flight Task Group 

Discovery at 

Edwards Air Force 

Base, California, 

after the completion 

of the STS-114 

mission. 

appeared more bottom-driven and without full development rigor. In addition, schedules were 

often underestimated due to a lack of understanding of the scope and timeline of development 

activities. 

Another reason these conditions arise is that senior program management is constantly 

pressing to lower cost by reducing the higher-priced technical personnel and replacing 

experienced engineers with recent graduates. 

As we resume the Space Shuttle flights it is important to make sure the right mix of technical 

personnel is maintained. A significant amount of flight test data will be generated during 

STS-114, requiring analysis and resulting in action plans for future work; additional fixes are 

yet to be completed. There must be an associated manpower and management plan through 

the remainder of the Space Shuttle Program. NASA should also consider the best contractual 

arrangements for finishing the program and assuring the proper skill mix and knowledge are 

transferred to the development of the next manned vehicle. 

A.10 Observations by Mr. Robert B. Sieck 

The CAIB report contained much information regarding issues with the culture in NASA and 

the Space Shuttle Program. The section on the performance of the MMT during the STS-107 

mission clearly characterized the issue, and the accident board offered appropriate findings 

and recommendations. 

The RTF TG members spent considerable time in the past two years observing – and 

participating – in Space Shuttle Program activities. In addition to numerous presentations 

from NASA and contractor management, the RTF TG was able witness the working level 

personnel performing their tasks. This included discussions during technical panels and 

working groups, problem resolution teams, control boards, and “hands-on” floor work. In 

general, there was high sensitivity among the participants to be thorough, attentive to details, 

encourage participation, and to take whatever additional time was necessary to collect 

relevant information before proceeding. It was encouraging to see that the engineers, 

technicians, and inspectors value the attention to detail as their work ethnic. 

The CAIB noted that “NASA’s safety culture has become reactive, complacent, and 

dominated by unjust optimism” (p. 180). NASA has undertaken initiatives to correct this, 

particularly in their management processes. However, the RTF TG observed that the 

“working level” culture is already consistent with what is required, and should continue to be 

fostered, for human space flight programs. 

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Final Report of the Return to Flight Task Group 

Space Center as 

STS-114. 

Discovery lifts-off 

from the Kennedy 

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Final Report of the Return to Flight Task Group 

during 

ascent wi

Solid Rocket 

Boosters and all 

Main Engines at full 

throttle. 

Discovery

th both 

three Space Shuttle 

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