MARCH 25, 2010

AUDIT REPORT

REPORT NO. IG-10-012 (ASSIGNMENT NO. A-09-012-00)

OFFICE OF AUDITS

REVIEW OF NASA’S PROGRESS ON RETIRING THE 

SPACE SHUTTLE PROGRAM

OFFICE OF INSPECTOR GENERAL

National Aeronautics and 

Space Administration
REPORT NO. IG-10-012

Final report released by:

/signed/

Paul K. Martin

Inspector General

Acronyms

AMS Alpha Magnetic Spectrometer

FY Fiscal Year

GAO Government Accountability Office

ISS International Space Station

JICB Joint Integration Control Board

NPR NASA Procedural Requirements 

NSTS National Space Transportation System 

OIG Office of Inspector General

STS Space Transportation System 

T&R Transition and Retirement

TCB Transition Control Board

ULF Utilization Logistics Flight
MARCH 25, 2010

REPORT NO. IG-10-012

OVERVIEW

REVIEW OF NASA’S PROGRESS ON RETIRING THE 

SPACE SHUTTLE PROGRAM

The Issue

In January 2004, the “Vision for U.S. Space Exploration” established a new direction for 

the Nation’s space program. As part of the Vision, the President directed NASA to use 

the Space Shuttle primarily to complete construction and outfitting of the International 

Space Station (ISS) before retiring the Shuttle by the end of 2010. A key challenge for 

NASA in achieving this objective is maintaining the capabilities required to fly the Space 

Shuttle safely while transitioning real and personal property, critical skills, and related 

capabilities to support other NASA priorities, including the next generation of human 

space flight systems. 

The objective of our audit was to evaluate NASA’s plans for completing the remaining 

Space Shuttle flights to support the ISS and retiring the Shuttle Program. To answer our 

objective, we analyzed the Space Shuttle flight rates and schedules to determine whether

the planned manifest appears reasonable and achievable. In addition, we reviewed 

NASA’s plans for transition and retirement (T&R) activities after the Shuttle Program’s 

retirement. Details of the audit’s scope and methodology are in Appendix A. 

Results

Since early 2004, NASA has maintained Space Shuttle flight manifests designed to 

sustain and complete construction of the ISS and retire the Shuttle Program by 

September 30, 2010. NASA has made steady progress in completing the scheduled 

flights and is working on a timetable to launch the remaining four flights and retire the 

Program by September 2010. However, our calculations and Agency internal reviews 

indicate that it will most likely take NASA until early 2011 to complete the last of the 

four remaining flights. Nevertheless, NASA continues working toward the September 

2010 Shuttle retirement date because it could potentially provide the Agency the 

opportunity to redirect millions of dollars toward other priority programs by limiting the 

need to fund Shuttle operations at $200 million a month in fiscal year (FY) 2011.

Further, while NASA has developed clear plans for managing the Shuttle Program’s

T&R activities through FY 2010, it has not finalized the organization and governance 

structure for T&R activities in FY 2011 and beyond.
OVERVIEW

ii REPORT NO. IG-10-012

Completing the Remaining Shuttle Flights by the End of FY 2010 Is Unlikely. 

NASA continues to fund and plan for completion of the four remaining Space Shuttle 

flights by September 30, 2010. According to Shuttle Program managers, the Agency 

chose to keep this schedule and not plan for flights in FY 2011 because the September 

2010 date is still manageable. Since that time, the President’s FY 2011 budget request 

was released and it includes an additional $600 million to support the Shuttle Program 

through December 2010.

Based on calculations by the Office of Inspector General, historical flight rates, and 

internal NASA evaluations, NASA is not likely to meet its September 2010 timetable, 

and it will most likely take until the second quarter of FY 2011 to complete the last of the 

planned Space Shuttle flights. For example, a Shuttle Program analysis of flight rates 

concluded that the estimated completion date for the last of the eight flights remaining as 

of June 2009 would be between November 2010 and March 2011, with February 2011 as 

the most realistic estimate. In addition, a September 2009 analysis of launch probabilities 

conducted by a consultant for the Space Operations Mission Directorate found that the 

probability for completing the six Shuttle flights remaining at that time by September 30, 

2010, ranged from 5 percent to 15 percent. The same analysis found that the probability 

of completing those flights by the end of December 2010 ranged from 70 percent to 

85 percent. 

Our calculations show that the chance of completing the remaining flights by the end of 

FY 2010 is improving. Specifically, with eight flights remaining our analysis concluded

that the final Shuttle flight would likely launch in June 2011. However, given that the 

last four Shuttle flights all launched within the schedule margins, our analysis now 

predicts that the last of the four remaining Shuttle flights will launch in January 2011. 

According to Shuttle Program managers, their philosophy is to manage and work toward

accomplishing the demanding launch schedule until the remaining schedule margin for 

accommodating launch delays is depleted. The managers estimate that accomplishing the 

work required to complete the remaining Space Shuttle flights by September 2010 will 

require up to $54 million in personnel overtime costs. However, they also estimate that 

the Agency will have to spend about $200 million for Shuttle Program operations for 

every month that they need to sustain Shuttle operations in FY 2011. Although the 

managers are holding to the end-of-FY 2010 retirement date and expect to expend up to 

$54 million in overtime costs, they recognize that they may still have to extend Shuttle 

operations into FY 2011 to complete the schedule due to uncontrollable events. 

Nevertheless, the managers stated that setting September 2010 as a goal can reduce the 

amount of time that they will need to sustain Shuttle operations in FY 2011 and 

potentially provide the Agency the opportunity to redirect millions of dollars toward 

other priority programs by limiting the need to continue Shuttle operations at 

$200 million a month.

NASA Has Not Finalized Post-2010 Transition and Retirement Plans. NASA and the 

Shuttle Program have clearly defined plans and an organization and governance structure 

for T&R activities through FY 2010. However, the Agency decided to delay finalizing 
OVERVIEW

REPORT NO. IG-10-012 iii

plans for T&R activities in FY 2011 and beyond in order to concentrate on completing 

the remaining Space Shuttle flights by September 2010. Space Operations Mission 

Directorate management stated that this decision allowed the Shuttle Program’s 

workforce to focus on the launch schedule and the existing T&R organization structure 

without being distracted by a “parallel” organization that Shuttle Program managers 

thought would distract the workforce and potentially affect flight safety.

Although NASA senior management has not finalized the post-2010 plans, NASA 

expects to implement a two-phase approach for the Shuttle Program’s retirement. Phase I 

(FY 2011 and FY 2012) will focus on asset “end-state development,” which is technical 

work to provide the asset in the required condition for disposal. Phase II (FY 2013 

through FY 2020) will focus on contract closeouts and any remaining asset disposal. 

As of March 2010, the organization and governance structure for executing T&R postFY 2010 was still under development, and the exact organizational responsibility for 

disposition of Program property after the last Space Shuttle mission had not yet been 

determined. Finalizing these matters prior to completion of the Space Shuttle Program is 

critical given the Program’s scope and the Agency’s estimate that T&R activities for 

FY 2011 through FY 2015 will cost $460 million.

Management Action

We made no recommendations concerning NASA’s plans to maintain the current Space 

Shuttle launch schedule given the Agency’s goal of attempting to minimize operating

costs for the Shuttle in FY 2011.

With respect to T&R activities, we recommended that the Associate Administrator for 

Space Operations finalize the post-FY 2010 organization structure and plans for T&R 

activities by July 31, 2010, to facilitate effective implementation of the full scope of T&R 

activities after the last Space Shuttle flight. 

In response to our March 12, 2010, draft of this report, the Associate Administrator for 

Space Operations concurred with our recommendation and stated that NASA is 

committed to the effective management of Shuttle T&R activities. The Space Shuttle 

Transition Manager prepared a draft proposal that establishes roles, responsibilities, and 

interfaces; describes the management approach and organization structure; and proposes 

personnel required to manage the final phases of Space Shuttle Program asset

dispositions. The Transition Manager expects to obtain approval from the Transition 

Control Board in April 2010 and finalize the plan by July 31, 2010. The estimated 

completion date is September 1, 2010. See Appendix B for the full text of management’s 

comments.

We consider the Associate Administrator’s proposed actions to be responsive. The 

recommendation is resolved and will be closed upon completion and verification of 

management’s corrective actions.

MARCH 25, 2010

REPORT NO. IG-10-012

CONTENTS

INTRODUCTION

Background _________________________________________ 1

Objective ___________________________________________ 3

RESULTS

Finding A: Completing the Remaining Shuttle Flights by the 

End of FY 2010 Is Unlikely ____________________ 4

Finding B: NASA Needs to Finalize Shuttle Post-2010 

Transition and Retirement Plans ______________ 12

APPENDIX A

Scope and Methodology_______________________________ 17

Review of Internal Controls ____________________________ 19

Prior Coverage ______________________________________ 19

APPENDIX B

Management Comments ______________________________ 20

APPENDIX C

Report Distribution___________________________________ 21

MARCH 25, 2010

REPORT NO. IG-10-012 1

INTRODUCTION

Background

The President’s “Vision for U.S. Space Exploration,” announced in January 2004, 

established a new direction for the Nation’s space program. As part of the Vision, 

President Bush directed NASA to use the Space Shuttle primarily to complete 

construction of the International Space Station (ISS) and then retire the Shuttle by 2010. 

In addition to the President’s announcement, in 2005 Congress directed the NASA 

Administrator to develop a plan describing how NASA would implement the President’s 

Vision.

1

 NASA’s Plan addressed how it would ensure that the Space Shuttle operates 

safely through its last flight; the planned number of flights before its retirement; other 

means that may be used to ferry crew and cargo to and from the ISS; the intended 

purpose of lunar missions; and the extent to which the new Crew Exploration Vehicle 

would allow for emergency crew escape. Subsequently in 2008, Congress mandated that 

NASA add two utilization logistics flights (ULFs)2

The Space Shuttle Program comprises four major projects

to the schedule (designated as ULF4 

and ULF5) and take all steps necessary to schedule a third flight (designated as ULF6)

prior to retiring the Shuttle in 2010. On February 1, 2010, the President released the 

proposed fiscal year (FY) 2011 budget for NASA. The proposed budget provides 

$600 million to complete the remaining Space Shuttle flights even if the schedule slips 

into FY 2011. The budget also supports extension of the ISS until at least 2020. 

3

NASA began dismantling the Shuttle Program during FY 2009, and prime contractors for 

the Space Shuttle began staff reductions in February 2009. Over the past year, 

contractors have closed down Shuttle production lines, hardware testing operations, and 

workstations.

and more than 1.2 million

pieces of hardware and equipment. The Space Shuttle is the only U.S. human-rated space 

transportation system. NASA’s Space Operations Mission Directorate is responsible for 

the safe and effective operation of the Space Shuttle; the lead manager for the Shuttle 

Program is located at Johnson Space Center. The Program employs more than 2,000 civil 

service and 15,000 contractor personnel, with the majority of the civil service workforce 

located at Johnson, Kennedy Space Center, and Marshall Space Flight Center. 

 1 Pursuant to the Authorization Act of 2005, NASA provided Congress with the “Human Space Flight 

Transition Plan,” July 2006. 

2 ULFs are Shuttle flights dedicated to delivering spare parts and supplies to the ISS.

3 The four projects are the Orbiter, the Space Shuttle Main Engine, the Reusable Solid Rocket Booster, and 

the External Tank.
INTRODUCTION

2 REPORT NO. IG-10-012

As of March 2010, four Space Shuttle flights are planned between April and September 

2010. The flights will complete the construction of the ISS and provide supplies for 

ISS’s sustainment through 2015. Upon completion of those flights, NASA will transition 

and retire the Shuttle Program. 

The ISS Program is an international partnership of the United States, Russia, Canada, 

Japan, and the members of the European Space Agency.4 Completion of the ISS is 

dependent on the Space Shuttle’s ability to provide the required assembly hardware, 

spare parts, and supplies necessary for the ISS to operate through at least 2015. 

Consequently, completion of the ISS is contingent on the remaining four planned Shuttle 

flights: one assembly flight and three ULFs. The remaining assembly flight is scheduled 

to deliver hardware, science payloads, an ammonia tank assembly, and a multi-purpose 

logistics module. The three ULFs will deliver three carriers containing spare parts such 

as a radiator,

5 science experiments, the Russian Mini-Research Module, an integrated 

cargo carrier, the Alpha Magnetic Spectrometer (AMS),

6

Previous Audit Work on Transition and Retirement. The NASA Office of Inspector 

General (OIG) and the Government Accountability Office (GAO) have previously

examined NASA’s planning for Space Shuttle Program transition and retirement (T&R) 

activities. In a 2007 report,

and a permanent logistics 

module for supply storage. 

7

We made four recommendations in our 2007 report intended to ensure that NASA 

developed the necessary framework, processes, and supporting infrastructure to manage 

and oversee the transition. Among them were recommendations that the Agency develop 

guidance within the NASA Procedural Requirements (NPR) 7120 series that clearly 

defines and establishes requirements for managing closeout and transition for programs 

of the Space Shuttle Program’s magnitude, revise the Human Space Flight Transition 

Plan to comply with applicable project management guidelines, and finalize and 

implement the Plan. NASA management took appropriate action to address all of the 

recommendations and, in August 2008, addressed transition planning through 2010 and 

established a structure for decision making to develop post-2010 T&R activities. 

we found that NASA’s transition plans did not 

comprehensively address certain elements that we believed were essential to management 

and oversight of an activity of the transition’s scope and importance. 

 4 European Space Agency members include Austria, Belgium, the Czech Republic, Denmark, Finland, 

France, Germany, Greece, Ireland, Italy, Luxembourg, the Netherlands, Norway, Portugal, Spain, 

Sweden, Switzerland, and the United Kingdom.

5 The radiator is a major sub-assembly of the ISS Heat Rejection Subsystem and consists of two radiator 

wings containing three radiators each. The radiator rejects heat from the ISS ammonia loop, and the 

panels cool the warm ammonia via radiant interchange with space. The radiator’s size and mass is such 

that the Space Shuttle is the only vehicle that can deliver it to the ISS.

6 While the AMS is not necessary for completing and supporting the ISS, the NASA Authorization Act of 

2008 requires the Administrator to take all necessary steps to make one additional Space Shuttle flight to 

deliver the AMS to the ISS prior to retiring the Space Shuttle. 

7 NASA OIG, “NASA’s Plans for Space Shuttle Transition Could Be Improved by Following Project 

Management Guidelines” (IG-07-005, January 29, 2007).
INTRODUCTION

REPORT NO. IG-10-012 3

A 2007 GAO report8 found that while NASA had developed plans and processes aimed 

at managing parts suppliers, several factors could impact NASA’s ability to effectively 

implement those plans and processes. GAO recommended that NASA develop cost 

estimates for T&R activities post-2010 so that NASA could request the necessary funding

in FY 2011 and beyond. In a 2008 report,9

Objective

GAO stated that NASA faced challenges in 

defining the scope and cost of Shuttle Program T&R activities. GAO recommended that 

NASA clearly identify all direct and indirect Shuttle Program T&R costs, noting that the 

Agency did not know what Program property it needed to retain or the full cost of the 

transition effort. In addition, GAO found that the Agency had not developed final plans 

and cost estimates for protecting Space Shuttle artifacts and making them available for 

public display. 

The audit’s overall objective was to evaluate the status of NASA’s efforts to complete the 

remaining Space Shuttle flights to support the ISS and retire the Shuttle Program. See 

Appendix A for details of the audit’s scope and methodology, our review of internal 

controls, and a list of prior audit coverage.

 8 GAO, “NASA Supplier Base: Challenges Exist in Transitioning from the Space Shuttle Program to the 

Next Generation of Human Space Flight Systems” (GAO-07-940, July 25, 2007).

9 GAO, “NASA: Agency Faces Challenges Defining Scope and Costs of Space Shuttle Transition and 

Retirement” (GAO-08-1096, September 30, 2008).
RESULTS

4 REPORT NO. IG-10-012

FINDING A: COMPLETING THE 

REMAINING SHUTTLE FLIGHTS 

BY THE END OF FY 2010

IS UNLIKELY

Since the President announced his “Vision for U.S. Space Exploration” in January 

2004, NASA has planned a Space Shuttle flight manifest designed to complete the 

ISS, support its sustainment, and retire the Shuttle Program by September 30, 2010. 

NASA has made steady progress in achieving these objectives, and only four Shuttle 

flights remained as of March 2010. However, both internal and external analyses 

indicate that NASA will not complete its final planned Shuttle flight until the second 

quarter of FY 2011. NASA continues working toward the September 2010 

retirement date because it could potentially provide the Agency the opportunity to 

redirect millions of dollars toward other priority programs by limiting the need to 

continue Shuttle operations at $200 million a month in FY 2011. 

Presidential and Congressional Mandates

Since 2004, the President and Congress have directed NASA to take a series of actions 

leading up to the cessation of the Space Shuttle Program. A summary of these directives 

follows.

President’s Vision. As part of his January 2004 “Vision for U.S. Space Exploration,”

the President directed NASA to return the Space Shuttle to flight as soon as practical

after the 2003 Columbia Shuttle disaster, use the Space Shuttle primarily to complete the 

ISS, and retire the Shuttle by 2010. 

NASA Authorization Act of 2005. The Act directed the NASA Administrator to use

Shuttle Program personnel, capabilities, assets, and infrastructure in developing NASA’s 

future launch vehicles. The Act also required the Administrator to transmit to Congress a 

plan describing how NASA would proceed with its future human space flight programs

and the retirement of the Shuttle Program. The plan was to include the projected number 

of flights the Space Shuttle would make before retirement and how NASA would deploy 

Shuttle Program resources to ensure that the Space Shuttle operates as safely as possible 

through its final flight. In addition, the Act required that the Administrator ensure that 

the ISS had sufficient on-orbit capabilities to sustain it through periods when the Space 

Shuttle or the next generation of space vehicles were unavailable. 

NASA Authorization Act of 2008. This Act mandated that NASA add two additional 

Space Shuttle flights to its planned flight schedule. The Act also required the 

Administrator to take all steps necessary to make an additional Space Shuttle flight to 
RESULTS

REPORT NO. IG-10-012 5

deliver the Alpha Magnetic Spectrometer (AMS) to the ISS prior to the Shuttle

Program’s retirement. 

If NASA determines that it will be unable to launch the AMS flight before the end of 

December 2010, or that the flight would result in significantly increased costs or 

unacceptable safety risks, the Act requires the Administrator to notify Congress and 

remove the AMS flight from the schedule. After such notification, however, Congress or 

the President may reauthorize the AMS flight by certifying that it is in the national 

interest. AMS flight (STS-134) is currently scheduled to launch on July 29, 2010. 

President’s Proposed FY 2011 Budget. On February 1, 2010, the President released the 

FY 2011 proposed budget for NASA. The budget requests $600 million to complete the 

remaining Space Shuttle flights if flights are delayed into FY 2011. The budget also 

supports extension of the ISS to at least 2020 and cancels the Constellation Program, 

which was NASA’s next generation human space flight program. 

NASA and OIG Analyses Suggest That Completing the Space 

Shuttle Flight Schedule Will Take Until Early 2011

NASA is working toward a September 30, 2010, completion date for the remaining four

Shuttle flights. However, historical flight rates and flight constraints suggest that NASA

will not complete its planned flights until the second quarter of FY 2011 at the earliest, as

shown in Table 1.

Table 1. Projected Date of Final Space Shuttle Launch

Basis of Projection Date

Historical Flight Rates February 2011

Manifest Assessment Simulation Tool March 2011*

NASA OIG Analysis January 2011

* Source: September 2009 calculations by the NASA consultant. 

Historical Flight Rate. In June 2009, NASA was planning to launch eight Space Shuttle 

missions over a 15-month period (June 2009 through September 2010). For the purpose 

of comparison, Shuttle Program managers evaluated historical flight rates for two other 

similar time periods. From June 2006 through November 2007, eight planned Shuttle 

launches took 20 months to complete. From June 2007 through October 2008, seven 

planned launches took 21 months to complete. Based on these rates, Shuttle Program

managers estimated that the eight Space Shuttle flights remaining as of June 2009 would 
RESULTS

6 REPORT NO. IG-10-012

be completed between November 2010 and March 2011, with February 2011 as the most

realistic estimate.

Manifest Assessment Simulation Tool. The Space Operations Mission Directorate uses 

the Manifest Assessment Simulation Tool10 to provide additional analyses of potential 

Shuttle flight schedules. The Assessment Tool provides a range of probabilities based on 

“likely case” and “worst case” scenarios.11

Table 2. Probability Results of the Manifest Assessment Simulation Tool

(95 percent confidence interval)

 In March 2009, the probability of completing 

the nine flights remaining on the March 17, 2009, manifest by the end of December 2010

was 78 percent (likely case) and 60 percent (worst case) according to the Assessment 

Tool. In September 2009, the Assessment Tool calculated the probability of completing 

the six flights remaining by September 2010, December 2010, or March 2011, as shown 

in Table 2.

Completion Date of Final 

Shuttle Flight

Likely Case Worst Case

September 2010 15 percent 5 percent

December 2010 85 percent 70 percent

March 2011 95 percent 90 percent

Source: September 2009 calculations by the NASA consultant.

NASA OIG. We estimated that the Shuttle Program will complete its four remaining 

Space Shuttle flights in January 2011. Our projection is based on the 88-day average for 

the number of days between Space Shuttle flights launched from July 2006 through

February 2010. To complete the flights by NASA’s current target date of September 30, 

2010, the Shuttle Program would need to reduce the average number of days between 

Space Shuttle flights to 55 – 33 days less than NASA’s historical average since July 

2006, and 60 days less than the Shuttle Program’s average since the Columbia disaster. 

The smaller schedule margin between Space Shuttle flights in 2010 leaves little room for 

launch delays. Any delay will likely affect subsequent flights, and completing the flight 

manifest by September 30, 2010, becomes correspondingly more unlikely. 

However, there is still a chance, although small, of achieving the September 2010 

retirement date if the Shuttles continue to launch on time or within the small schedule 

 10The Manifest Assessment Simulation Tool provides a quantitative estimate on when Space Shuttle 

missions are likely to take place based on planned flight dates.

11Likely case and worst case scenarios are distinguished by the probability of negative events occurring. 

For example, the Space Shuttle landing at Dryden Flight Research Center instead of Kennedy Space 

Center is considered a negative event, as it would add 10 days to the ground processing time required to 

prepare the Shuttle for its next flight. The probability of this event in a likely case scenario is 1 in 9; its 

probability in a worst case scenario is 1 in 5.
RESULTS

REPORT NO. IG-10-012 7

margins. Our analysis indicates that the probability of meeting the demanding schedule 

improved by 5 months (from June 2011 to January 2011) when the last four flights 

launched within their launch window margins. We performed our analysis based on 

average number of days between Shuttle launches when there were eight flights 

remaining; seven flights remaining; six flights remaining; five flights remaining; and,

finally, four flights remaining. Each time the Shuttle launched within the window 

margin, the average days between launches decreased and our projection for when the 

last flight would launch improved. 

Table 3 below shows the results of our analysis with eight, seven, six, five, and four

flights remaining.

Table 3. NASA OIG Projection for Final Shuttle Flight

Flights Remaining Historical Days 

Between Launches

Projected Last 

Shuttle Flight

Eight 95 June 2011

Seven 92 April 2011

Six 89 February 2011

Five 88 January 2011

Four 88 January 2011

Factors Affecting the Space Shuttle Launch Schedule

Additional factors in maintaining the flight schedule include how long one launch can be 

delayed without impacting the next launch (schedule margin), how long it takes to 

prepare a Shuttle between flights (ground processing margin), and launch windows.

Schedule Margin. The schedule margin between flights is the length of time the Shuttle 

Program can delay a launch before causing a delay in the next scheduled Space Shuttle 

flight. With every launch delay, the schedule margins become smaller. Based on the 

March 2010 launch schedule, the margins between subsequent launch windows ranged

from zero to 3 weeks for the four remaining flights (see Table 4). For example, STS-131

has no schedule margin, and any delay in its planned April 5, 2010, launch would cause a 

delay for the next launch (STS-132, scheduled for May 14, 2010). Similarly, a delay 

longer than 3 weeks by STS-132 would require recalculation of the launch schedule for at 

least one of the remaining Shuttle flights into FY 2011. 
RESULTS

8 REPORT NO. IG-10-012

Table 4. Space Shuttle Launch Schedule as of March 2010

Designation Assigned Shuttle Launch Date Schedule Margin*

STS-131 Discovery April 5, 2010 0 weeks

STS-132/ULF4 Atlantis May 14, 2010 3 weeks

STS-134/ULF6 Endeavour July 29, 2010 2 weeks

STS-133/ULF5 Discovery September 16, 2010

*Length of time the Space Shuttle Program can delay a launch before causing a delay in the next 

scheduled flight.

Source: Space Shuttle Program planning documents as of June 2009 and March 2010.

Ground Processing Margin. The ground processing margin is the time it takes to ready 

a Space Shuttle for its next flight. In addition to the small schedule margins between 

flights, the Shuttle Program must also manage the margin for ground processing between 

flights of the same Space Shuttle. During 2009, the Program’s schedules allowed for 

delays of up to 4 weeks. For example, Space Shuttle Discovery was scheduled for flights 

in August 2009 and March 2010. When the August Discovery launch was delayed by 

3 weeks, the Shuttle Program still had 1 week of ground processing margin to prepare 

Discovery for its March launch, which has subsequently been delayed to April 5, 2010. 

As a result, there is no ground margin between the remaining two flights for Discovery 

(April 5 and September 16), so a delay of Discovery’s April 5, 2010, launch would result 

in Discovery’s planned September 16 launch slipping into FY 2011. 

Launch Windows. The best possible time to launch the Space Shuttle, known as the 

launch window, is dependent on a number of constraints, such as Solar Beta Angle,12

NASA’s current position that the four remaining Space Shuttle launches could be 

completed by September 30, 2010, was partly based on an increase in FY 2010 of the 

number of available flight days, or launch opportunities. Table 5 shows the planned 

available flight days by fiscal year as of June 2009.

launch pad availability, weather conditions, and the presence of other space vehicles at 

the ISS (such as the Russian Soyuz or Japanese H-II Transfer Vehicle).

 12The Shuttle cannot be docked to the ISS during Solar Beta Angle, a recurring condition that happens 

when the angle between the ISS orbit and the Sun produces unacceptably high temperatures.
RESULTS

REPORT NO. IG-10-012 9

Table 5. Planned Number of Available Space Shuttle Flight Days 

(by fiscal year)

Fiscal Year Number of Available Days

2006 92

2007 215

2008 196

2009 180

2010 265

Source: Space Shuttle Program planning documents, June 2009.

As shown in Table 5, NASA was planning on a significant increase in launch 

opportunities in FY 2010 (85 more days than in FY 2009) and planned the four remaining 

Shuttle launches in FY 2010 accordingly. The planned increase in launch opportunities 

for the Space Shuttle resulted from a projected reduction in the number of Russian Soyuz 

flights to the ISS. However, that reduction did not occur as projected. Consequently, 

NASA expects that the number of available flight days for the Space Shuttle in FY 2010 

will be about the same as FY 2009, further limiting the available launch windows and 

reducing margins. 

Management Decision to Maintain the Current Schedule

To date, NASA managers are still working on a timetable that has the final Space Shuttle 

mission taking place in September 2010. Shuttle Program management calculates the 

time it takes to ready the Shuttle for flight using no margin for processing and then 

schedules the Shuttle for launch in the next available launch window. By so doing, 

schedule margin is inevitably established by the time between the planned end of 

processing and the launch window. Although the internal and external analyses conclude 

that NASA will not meet this timetable, there is still a chance to obtain the 

September 2010 retirement date if the Space Shuttles launch on time or within the small 

margins. The last four Shuttles launched within the allowed margins and did not delay 

subsequent launches, thereby improving NASA’s chances to complete the flights on 

schedule. For example, our original analysis with eight flights remaining showed that the 

last Shuttle would not launch until June 2011. Because the last four launches occurred 

within their window margins, our analysis now predicts the last launch date as 

January 2011. To realize the September 2010 completion date, however, the Shuttle 

Program will need to continue launching within its very tight schedule margins. 

Shuttle Program personnel stated that their schedule management philosophy is to hold to 

the established retirement date for planning purposes, with the expectation that delays 

could force flights into FY 2011. Program personnel stated that based on their 

experience, by managing the Shuttle’s launch schedule for completion by September 30, 

2010, and not revising it until the schedule margin is depleted, the more realistic 
RESULTS

10 REPORT NO. IG-10-012

completion date of February 2011 will be met and a final Shuttle flight by 

December 2010 could well be achieved. 

Schedule and ISS Sustainment

In an attempt to preserve the planned September 2010 completion of Space Shuttle 

flights, the Shuttle Program will spend as much as $54 million in overtime in FY 2010 to

expedite Shuttle processing. The timely completion of the Space Shuttle manifest could 

potentially provide the Agency the opportunity to redirect millions of dollars toward 

other priority programs by limiting the need to continue Shuttle operations at 

$200 million a month and in addition, help ensure the sustainment of ISS operations 

through 2015 and beyond.

Overtime Costs to Maintain Schedule. In support of NASA’s current Space Shuttle 

launch schedule, the Agency intends to spend up to $54 million in personnel overtime 

costs to facilitate completion of the remaining flights by what all agree is a challenging 

launch schedule. When we discussed this issue with Shuttle Program personnel, they 

stated that the $54 million investment for overtime will help ensure the most expeditious 

completion of the Space Shuttle flight schedule, even if all launches are not completed by 

the end of September 2010. 

By holding to the end-of-FY 2010 retirement date and spending up to $54 million in 

overtime to achieve that goal, Shuttle Program managers expect to complete the 

scheduled flights months earlier than would be possible if a new flight manifest were 

created based on a December 2010 retirement date. Because operation costs for the 

Shuttle Program run about $200 million a month, completing the remaining flights just 

1 week earlier would about equal the Agency’s planned overtime investment. 

ISS Assembly and Sustainment. The final stages of ISS assembly and sustainment 

depend on the success of the remaining Space Shuttle flights. Without these flights, the 

likelihood of the ISS operating as intended through FY 2015 or beyond is significantly 

reduced. The remaining Shuttle flights are scheduled to deliver internal and external 

orbital replacement units for the ISS, units that are critical to support a six-person ISS 

crew and reduce the need for continued maintenance on existing equipment. While the 

ISS can rely on its international partners’ vehicles – such as the Russian Soyuz; Progress, 

the European Automated Transfer Vehicle; and the Japanese H-II Transfer Vehicle – to 

deliver spare parts and supplies, only the Space Shuttle is capable of delivering certain 

larger items to the ISS. One such item is a spare radiator that STS-133 is scheduled to 

deliver to the ISS in September 2010. 
RESULTS

REPORT NO. IG-10-012 11

Management Action

In light of the Agency’s attempts to reduce operating costs for the Shuttle in FY 2011, we 

are not making a recommendation that NASA adjust its current Space Shuttle flight 

manifest.
RESULTS

12 REPORT NO. IG-10-012

FINDING B: NASA NEEDS TO 

FINALIZE SHUTTLE POST2010 TRANSITION AND 

RETIREMENT PLANS

NASA had clearly defined plans for Space Shuttle transition and retirement (T&R) 

activities through FY 2010, but has not finalized the organization and governance 

structure for T&R activities after FY 2010. Although NASA senior management has 

yet to finalize the post-2010 plans, NASA managers said they expect to implement a 

two-phase approach for the Shuttle Program’s retirement. Phase I (FY 2011 and 

FY 2012) will focus on asset “end-state development,” which is technical work to 

provide the asset in the required condition for disposal. Phase II (FY 2013 through

FY 2020) will focus on contract closeouts and any remaining asset disposal. NASA 

deferred finalizing the planning for Shuttle Program T&R activities to concentrate on 

completing Space Shuttle flights by September 2010, but without finalized plans the 

Agency lacks the necessary framework, processes, and supporting infrastructure to 

manage the estimated $460 million that will be needed for T&R activities beginning 

in FY 2011.

Management of Space Shuttle Program Retirement

In a 2007 report, the OIG addressed NASA’s efforts to plan for and manage the Shuttle 

Program’s T&R activities.

13

NASA management concurred with our finding and agreed to define requirements for a 

final post-2010 Shuttle transition workforce, management structure, and organization. 

The transition management plan developed in August 2008 addressed transition planning 

through 2010 and established a structure for decision making to develop post-2010 T&R 

activities that involved joint planning with NASA Mission Directorates, Centers, program 

offices, mission support offices, and associated industry contractors. 

 The audit found that the Agency’s transition plan did not 

address critical issues, such as who will manage facilities and property disposition or who 

will make transition decisions after the planned 2010 retirement. We recommended that 

NASA establish guidance for managing the transition after 2010 because many of the 

critical property and equipment dispositions will not occur until 2011. In addition, we 

reported that to effectively manage and successfully complete the Space Shuttle 

transition, NASA should define the roles and responsibilities for transition activities after 

the Shuttle Program ends and its managers no longer provide the lead role in the 

transition. 

 13NASA OIG, “NASA’s Plans for Space Shuttle Transition Could Be Improved by Following Project 

Management Guidelines” (IG-07-005, January 29, 2007).
RESULTS

REPORT NO. IG-10-012 13

Agency Lacks Post-Shuttle Program T&R Organization and Plans

NASA defines Space Shuttle T&R activities as the tasks required to identify all Shuttle 

Program capabilities and either transfer these capabilities to another program or 

institution or retire the Shuttle Program’s capabilities that are no longer needed. Since 

our 2007 audit of NASA’s transition plans for the Space Shuttle, the Agency has made

significant progress in managing the Shuttle’s retirement while continuing to operate and 

fly the Shuttle. The current plans use the Shuttle Program’s management structure and 

decision-making boards for T&R activities, and the Agency relies heavily on Shuttle 

Program management to budget T&R costs within the Shuttle line item. In addition, the 

Agency is studying alternatives for the post-Shuttle T&R organization to ensure assets 

are in the proper condition for disposition. However, as of March 2010, the Agency still 

did not have a clearly defined organization structure or plans for T&R activities after the 

Shuttle’s planned September 2010 retirement date, even though that date was less than 

6 months away. 

Pre-Shuttle Retirement Activities. Over the past several years, NASA and Shuttle 

Program managers began planning for the Program’s retirement by implementing a series 

of transition plans:

• National Space Transportation System 07700, Volume XX, “Space Shuttle 

Transition and Retirement Requirements,” February 28, 2007, establishes the 

program-level requirements for the Shuttle Program’s T&R activities.

• “Space Shuttle Program Transition Management Plan,” May 9, 2007, describes 

the organization structure, management approach, processes, products, and tools 

to manage the transition and retirement of the Shuttle Program’s capabilities. In 

addition, this plan defines how the Shuttle Program is organizing and managing 

implementation of its end-of-program T&R and align it with the Human Space 

Flight Transition Plan. 

• “NASA Transition Management Plan,” August 2008, provides the strategic 

foundation for the management and execution of transition efforts. This plan 

contains the Agency-level goals, objectives, roles, and responsibilities necessary 

to execute the transition efforts.

In addition to these transition plans, the Agency established a working group and control 

boards between 2006 and 2009 to help ensure that Shuttle Program T&R activities are 

implemented effectively. Descriptions of the working group and boards follow.

• The Headquarters Transition Working Group performs cross-functional 

coordination across Agency organizations contributing to or impacted by the 

retirement of the Shuttle Program, the transition of assets and capabilities to 

Constellation, or the disposition and disposal of assets and capabilities.
RESULTS

14 REPORT NO. IG-10-012

• The Human Space Flight Transition Control Board (TCB) comprises the Space 

Operations and Exploration Systems Mission Directorates, the Institutions and 

Management Office, the Safety and Mission Assurance Office, and the Office of 

the Chief Engineer. The TCB coordinates transition planning, as well as reviews

and approves Shuttle Program, ISS, and Constellation Program plans and 

decisions concerning Shuttle Program resources and how assets are to be 

transitioned. The TCB charter expires September 30, 2010.

• The Joint Integration Control Board (JICB) provides integrated strategic direction 

and decision making; determines integrated priorities and risk mitigation 

strategies; defines budgets, schedules, and Agency-level human space flight 

development and operation requirements; serves as the Directorate-level interorganizational forum; and ensures that lessons learned are transferred into the 

Constellation Program’s development and operations. The JICB charter also 

expires September 30, 2010.

• The Infrastructure Transition Control Board, chaired by the Assistant 

Administrator, Office of Infrastructure, has authority to institute infrastructure 

transition policies and procedures, evaluate progress, and direct actions necessary 

to achieve the Agency’s transition goals. The charter for the Infrastructure 

Transition Control Board expires September 30, 2012.

Shuttle Program managers also said they have made progress on pre-FY 2011 T&R 

activities through the following:

• Creating a Strategic Capability Assessment database that categorizes Shuttle 

Program assets and defines capability requirements through the end of the 

program. The capability assessment defines the last date each capability is 

needed, facilitating management decisions on whether to retain, transfer, preserve, 

or dispose of the capabilities.

• Tracking major transition milestone schedules that include the Shuttle Program 

decommissioning review.

14

• Managing a single-source supplier list to manage its supplier base through the 

retirement of the Shuttle Program. NASA uses the list to monitor the unique 

capabilities provided by suppliers.

 

• Implementing the Space Shuttle Management Resource Transition Document 

process as a primary tool for ensuring that credible, consistent, and accurate 

information is provided to management for decision making. 

 14The Shuttle Program will perform a decommissioning review, planned for August 2010, to confirm the 

decision to terminate or decommission the Program and assess the readiness of the Program to dispose of 

its assets.
RESULTS

REPORT NO. IG-10-012 15

Final Planning for Post-Shuttle T&R Activities Delayed

The Agency decided to delay finalizing plans for managing an estimated $460 million of 

T&R activities in FY 2011 and beyond in order to concentrate on completing the Space 

Shuttle flight manifest. Space Operations Mission Directorate management stated that

this decision allowed the Shuttle Program’s workforce to focus on the launch schedule 

and the existing T&R organization structure without being distracted by a “parallel” 

organization that Shuttle Program managers thought would distract the workforce and 

potentially affect flight safety. Although NASA senior management has yet to finalize

the planned post-FY 2010 organization, NASA managers said they expect to implement a 

two-phase plan for the Shuttle Program’s retirement. Phase I (FY 2011 and FY 2012) 

will focus on asset “end-state development,” which is technical work to provide the asset 

in the required condition for disposal. Phase II (FY 2013 through FY 2020) will focus on 

contract closeouts and any remaining asset disposal. During Phase II, the Centers will 

dispose of Shuttle assets using normal NASA and Center procedures. 

Ensuring that the plan for post-FY 2010 T&R activities is approved and formalized prior 

to the Shuttle Program’s retirement is important because many of the critical dispositions 

will occur in FY 2011 and beyond. As of March 2010, the organization and governance 

structure for executing T&R post-FY 2010 was still under development. In addition, the 

charters for both the TCB and JICB expire at the end of FY 2010. Although Shuttle 

Program managers included budget estimates for FYs 2011–2012 T&R activities as part 

of the FY 2011 budget submission process, the exact organizational responsibility for 

disposition of Program property after the last Space Shuttle mission has not yet been 

finalized. In December 2009, we initiated an audit to evaluate the reasonableness of 

Shuttle Program’s cost estimate of T&R activities. Because those estimates were largely 

based on transition to the Constellation Program, which is proposed for cancellation in 

the President’s FY 2011 budget, we have suspended our review until NASA evaluates 

and establishes a new cost estimate.

Recommendation, Management’s Response, and Evaluation of 

Management’s Response

We recommended that the Associate Administrator for Space Operations finalize the 

post-FY 2010 organization structure and plans for T&R activities by July 31, 2010, to 

facilitate effective implementation of the full scope of T&R activities after the last Space 

Shuttle flight. 

Management’s Response. The Associate Administrator for Space Operations concurred 

with the recommendation and stated that the post-FY 2010 organization structure and 

plans should be finalized by July 31, 2010. Specifically, the Associate Administrator 

stated that the Space Shuttle Transition Manager prepared a draft proposal that 

established the Level II Transition Program Office roles, responsibilities, and interfaces; 

describes the management approach and organization structure; and proposes the fulltime 
RESULTS

16 REPORT NO. IG-10-012

personnel equivalents required to manage the final phases of transition and retirement of 

Space Shuttle assets. According to the Associate Administrator, the Transition Manager 

intends to present this plan to the Transition Control Board in April 2010 and finalize it 

by July 31, 2010. The plan will be included in an update of the National Space 

Transportation System 60576, SSP Transition Management Plan. The estimated 

completion date is September 1, 2010. 

Evaluation of Management’s Response. The Associate Administrator’s response and 

planned actions are responsive to the recommendation. Therefore, the recommendation 

is resolved; however, it will remain open until we review the Agency’s final transition 

plan.
APPENDIXES

REPORT NO. IG-10-012 17

APPENDIX A

Scope and Methodology

We performed this audit from May 2009 through March 2010 in accordance with 

generally accepted government auditing standards. Those standards require that we plan 

and perform the audit to obtain sufficient, appropriate evidence to provide a reasonable 

basis for our findings and conclusions based on our audit objectives. We believe that the 

evidence obtained provides a reasonable basis for our findings and conclusions based on 

our audit objectives. We performed our audit work at Johnson Space Center and NASA 

Headquarters.

To evaluate NASA’s plans for completing the remaining Shuttle flights, completing and 

supporting the ISS, and retiring the Shuttle Program, we reviewed the following Federal 

laws and NASA regulations, policies, and procedures:

• “Omnibus Appropriations Act, 2009,” Public Law 111-8, March 11, 2009

• “National Aeronautics and Space Administration Authorization Act of 2008,” 

October 2008

• “National Aeronautics and Space Administration Authorization Act of 2005,” 

December 2005 

• NASA’s “Fiscal Year 2011 Budget Estimates,” February 1, 2010 

• NASA Procedural Requirements (NPR) 7120.5D, “NASA Space Flight Program 

and Project Management Requirements,” March 6, 2007 

• NPR 7123.1A, “NASA Systems Engineering Processes and Requirements,” 

March 26, 2007, and NASA Interim Directive, November 4, 2008

• “NASA Transition Management Plan For Implementing the U.S. Space 

Exploration Policy,” August 2008 

• National Space Transportation System (NSTS) 60575, “Space Shuttle Program 

Transition and Retirement Environmental Plan,” June 15, 2007

• NSTS 60576, “Space Shuttle Program Transition Management Plan,” May 9, 

2007 

• NSTS 07700, Volume XX, “Space Shuttle Program Transition and Retirement 

Requirements,” February 28, 2007 
APPENDIX A

18 REPORT NO. IG-10-012

In addition, to gain an overall understanding of NASA’s plans for retiring the Shuttle 

Program, we reviewed the following plans and reports:

• “International Space Station Program Plan,” September 22, 2003 (ISS Program 

Office)

• “Space Shuttle Program Plan,” May 9, 2008 (Space Shuttle Program Office)

• “Program Implementation Review Management Briefing,” July 21, 2008 (Space 

Shuttle Program Office and ISS Program Office)

• “Space Station Program Transition and Retirement Personal Property Disposition 

Plan,” November 2008 (Space Shuttle Program Office)

• “Extending the Space Shuttle Program Beyond 2010, draft,” February 9, 2009 

(Space Shuttle Program Office)

• NASA’s “Aerospace Safety Advisory Panel Report for 2008,” April 15, 2009 

• NASA’s “Aerospace Safety Advisory Panel Annual Report for 2009,” January 15, 

2010 

• Congressional Budget Office Report, “The Budgetary Implications of NASA’s 

Current Plans for Space Exploration,” April 2009

• NASA’s “Impacts of Suspending Activity before April 30, 2009 That Would 

Preclude Extending Space Shuttle Operations,” April 2009

• NASA’s “Report on Costs for Space Shuttle Transition and Retirement Activities 

Pursuant to FY 2009 Omnibus Appropriations Act (P.L. 111-8),” July 6, 2009 

We interviewed the Space Operations Mission Directorate’s Transition Manager and 

Shuttle Program personnel from the Flight Operations and Integration Office, the 

Business Office, and the Management Integration and Planning Office. We also 

interviewed ISS Program personnel from the Program Integration Office, Mission 

Integration and Operations Office, and External Integration Office.

We analyzed the current and historical flight rates to determine whether the planned 

Shuttle flight schedule is reasonable and achievable. We reviewed NASA’s costs

incurred for retirement and the estimated costs associated with T&R activities post-2010. 

We also reviewed the Shuttle Program’s FY 2011 budget submission.

Use of Computer-Processed Data. We did not perform a detailed assessment of the 

reliability of the values and information reported in the Space Shuttle and ISS risk 

databases. We reviewed these databases to determine whether the programs identified 

risks for meeting the current Shuttle flight schedule and whether mitigation strategies 
APPENDIX A

REPORT NO. IG-10-012 19

were in place to ensure successful completion of the manifest. For ISS risks, we 

reviewed estimated costs for mitigation of the risks, but did not validate those values. 

We used the probability results from the Manifest Assessment Simulation Tool as 

additional support for estimating a schedule completion date. However, we did not 

perform a detailed review on the assumptions incorporated into the tool.

Review of Internal Controls 

We reviewed internal controls for the Shuttle Program’s mission and T&R activities 

related to authority, responsibility, and organization structure; policies and procedures; 

and oversight functions. “NASA Transition Management Plan,” August 2008, defined 

roles and responsibilities and provided for a transition governance structure; however, the 

plan did not address post-FY 2010 Shuttle Program organization and governance 

structure. The recommendation in this report, if implemented, should improve the 

internal controls over the T&R process.

Prior Coverage

During the last 5 years, the NASA OIG and GAO have issued three reports related to the 

subject of this report. These reports can be found on the Internet at 

http://oig.nasa.gov/audits/reports/FY10/index.html and http://www.gao.gov. 

Office of Inspector General, National Aeronautics and Space Administration

“NASA’s Plan for Space Shuttle Transition Could Be Improved by Following Project 

Management Guidelines” (IG-07-005, January 29, 2007)

Government Accountability Office

“NASA: Agency Faces Challenges Defining Scope and Costs of Space Shuttle Transition 

and Retirement” (GAO-08-1096, September 30, 2008)

“NASA Supplier Base: Challenges Exist in Transitioning from the Space Shuttle 

Program to the Next Generation of Human Space Flight Systems” (GAO-07-940, July 25, 

2007)
APPENDIX B

20 REPORT NO. IG-10-012

MANAGEMENT COMMENTS
APPENDIX C

REPORT NO. IG-10-012 21

REPORT DISTRIBUTION

National Aeronautics and Space Administration

Administrator

Deputy Administrator

Associate Administrator, Exploration Systems Mission Directorate

Associate Administrator, Space Operations Mission Directorate

Director, Johnson Space Center

Director, Kennedy Space Center

Director, Marshall Space Flight Center

Program Manager, Space Shuttle Program

Program Manager, International Space Station Program

Associate Manager, Space Shuttle Program

Non-NASA Organizations and Individuals

Office of Management and Budget

Deputy Associate Director, Energy and Science Division

Branch Chief, Science and Space Programs Branch

Government Accountability Office

Director, NASA Financial Management, Office of Financial Management and 

Assurance

Director, NASA Issues, Office of Acquisition and Sourcing Management

Congressional Committees and Subcommittees, Chairman and 

Ranking Member

Senate Committee on Appropriations

Subcommittee on Commerce, Justice, Science, and Related Agencies

Senate Committee on Commerce, Science, and Transportation

Subcommittee on Science and Space

Senate Committee on Homeland Security and Governmental Affairs

House Committee on Appropriations

Subcommittee on Commerce, Justice, Science, and Related Agencies

House Committee on Oversight and Government Reform

Subcommittee on Government Management, Organization, and Procurement

House Committee on Science and Technology

Subcommittee on Investigations and Oversight

Subcommittee on Space and Aeronautics

REPORT NO. IG-10-012 23

Major Contributors to the Report:

Raymond Tolomeo, Acting Director, Space Operations Directorate

Loretta Atkinson, Project Manager

Jim Griggs, Lead Auditor

Eugene Bauer, Auditor

Barbara Moody, Auditor

Doug Orton, Auditor

Frank Martin, Aerospace Technologist

Liz Shifflett, Editor
MARCH 25, 2010

REPORT No. IG-10-012

OFFICE OF AUDITS

OFFICE OF INSPECTOR GENERAL

ADDITIONAL COPIES

Visit http://oig.nasa.gov/audits/reports/FY10/ to obtain additional copies of this report, or contact the 

Assistant Inspector General for Auditing at 202-358-1232.

COMMENTS ON THIS REPORT

In order to help us improve the quality of our products, if you wish to comment on the quality or 

usefulness of this report, please send your comments to Mr. Laurence Hawkins, Audit Operations and 

Quality Assurance Director, at Laurence.B.Hawkins@nasa.gov or call 202-358-1543.

SUGGESTIONS FOR FUTURE AUDITS

To suggest ideas for or to request future audits, contact the Assistant Inspector General for Auditing. 

Ideas and requests can also be mailed to:

Assistant Inspector General for Auditing

NASA Headquarters

Washington, DC 20546-0001

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