****Report of the PRESIDENTIAL COMMISSIONon the Space Shuttle Challenger Accident****
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****Chapter VIII: Pressures on theSystem.****
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** **

[**164**] With the 1982completion of the orbital flight test series, NASA began a plannedacceleration of the Space Shuttle launch schedule. One early plancontemplated an eventual rate of a mission a week, but realism forcedseveral downward revisions. In 1985, NASA published a projectioncalling for an annual rate of 24 flights by 1990. Long before theChallenger accident, however, it was becoming obvious that even themodified goal of two flights a month was overambitious.

In establishing the schedule, NASA had notprovided adequate resources for its attainment. As a result, thecapabilities of the system were strained by the modest nine-missionrate of 1985, and the evidence suggests that NASA would not have beenable to accomplish the 15 flights scheduled for 1986. These are themajor conclusions of a Commission examination of the pressures andproblems attendant upon the accelerated launch schedule.

On the same day that the initial orbital testsconcluded-July 4, 1982-President Reagan announced a national policyto set the direction of the U. S. space program during the followingdecade. As part of that policy, the President stated that:

> 
"The United States SpaceTransportation System (STS) is the primary space launch system forboth national security and civil government missions."

Additionally, he said:

> 
"The first priority of the STSprogram is to make the system fully operational and cost-effective inproviding routine access to space."

From the inception of the Shuttle, NASA hadbeen advertising a vehicle that would make space operations "routineand economical." The greater the annual number of flights, thegreater the degree of routinization and economy, so heavy emphasiswas placed on the schedule. However, the attempt to build up to 24missions a year brought a number of difficulties, among them thecompression of training schedules, the lack of spare parts, and thefocusing of resources on nearterm problems.

One effect of NASA's accelerated flight rateand the agency's determination to meet it was the dilution of thehuman and material resources that could be applied to any particularflight.

The part of the system responsible for turningthe mission requirements and objectives into flight software, flighttrajectory information and crew training materials was struggling tokeep up with the flight rate in late 1985, and forecasts showed itwould be unable to meet its milestones for 1986. It was fallingbehind because its resources were strained to the limit, strained bythe flight rate itself and by the constant changes it was forced torespond to within that accelerating schedule. Compounding the problemwas the fact that NASA had difficulty evolving from its singleflightfocus to a system that could efficiently support the projected flightrate. It was slow in developing a hardware maintenance plan for itsreusable fleet and slow in developing the capabilities that wouldallow it to handle the higher volume of work and training associatedwith the increased flight frequency.

[**165**] Pressures developedbecause of the need to meet customer commitments, which translatedinto a requirement to launch a certain number of flights per year andto launch them on time. Such considerations may occasionally haveobscured engineering concerns. Managers may have forgotten-partlybecause of past success, partly because of their own well-nurturedimage of the program-that the Shuttle was still in a research anddevelopment phase. In his testimony before a U.S. SenateAppropriations subcommittee on May 5, 1982, following the thirdflight of the Space Shuttle, James Beggs, then the NASAAdministrator, expressed NASA's commitment:

> 
"The highest priority we have setfor NASA is to complete development of the Shuttle and turn it intoan operational system. Safety and reliability of flight and thecontrol of operational costs are primary objectives as we moveforward with the Shuttle program."**1**

Sixteen months later, arguing in support ofthe Space Station, Mr. Beggs said, "We can start anytime.... There'sno compelling reason [why] it has to be 1985 rather than '86 or '87.The point that we have made is that the Shuttle is now operational."**2** The prevalent attitude in the program appeared to bethat the Shuttle should be ready to emerge from the developmentalstage, and managers were determined to prove it "operational."

Various aspects of the mission design anddevelopment process were directly affected by that determination. Thesections that follow will discuss the pressures exerted on the systemby the flight rate, the reluctance to relax the optimistic schedule,and the attempt to assume an operational status.

** **

**Planning of a Mission**

The planning and preparation for a SpaceShuttle flight require close coordination among those making theflight manifest, those designing the flight and the customerscontracting NASA's services. The goals are to establish the manifest;define the objectives, constraints and capabilities of the mission;and translate those into hardware, software and flightprocedures.

There are major program decision points in thedevelopment of every Shuttle flight. At each of these points,sometimes called freeze points, decisions are made that form thebasis for further engineering and product development. Thedisciplines affected by these freeze points include integrationhardware, engineering, crew timeline, flight design and crewtraining.

The first major freeze point is at launchminus 15 months. At that time the flight is officially defined: thelaunch date, Orbiter and major payloads are all specified, andinitial design and engineering are begun based on thisinformation.

The second major freeze point is at launchminus 7.7 months, the cargo integration review. During this review,the integration hardware design, Orbiter vehicle configuration,flight design and software requirements are agreed to and specified.Further design and engineering can then proceed.

Another major freeze point is the flightplanning and stowage review at launch minus five months. At thattime, the crew activity timeline and the crew compartmentconfiguration, which includes middeck payloads and payload specialistassignments, are established. Final design, engineering and trainingare based on these products.

** **

**Development of Flight Products**

The "production process" begins by collectingall mission objectives, requirements and constraints specified by thepayload and Space Shuttle communities at the milestones describedabove. That information is interpreted and assimilated as variousgroups generate products required for a Space Shuttle flight:trajectory data, consumables requirements, Orbiter flight software,Mission Control Center software and the crew activity plan, to namejust a few.

Some of these activities can be done inparallel, but many are serial. Once a particular process has started,if a substantial change is made to the flight, not only does thatprocess have to be started again, but the process that preceded itand supplied its data may also need to be repeated. If one groupfails to meet its due date, the group that is next in the chain willstart late. The delay then cascades through the system.

Were the elements of the system meeting theirschedules? Although each group believed it had an adequate amount oftime allotted to perform its function, the system as a whole wasfalling....

** **

******[**166**]**
********
**Graph depicts beginning of simulatortraining for Shuttle crews in days before launch for missions 41-Bthrough 61-E.******
** **

....behind. An assessment of the system'soverall performance is best made by studying the process at the endof the production chain: crew training. Analysis of trainingschedules for previous flights and projected training schedules forflights in the spring and summer of 1986 reveals a clear trend: lessand less time was going to be available for crew members toaccomplish their required training. (See the Shuttle missionsimulator training chart.)

The production system was disrupted by severalfactors including increased flight rate, lack of efficient productionprocessing and manifest changes.

** **

**Changes in the Manifest**

Each process in the production cycle is basedon information agreed upon at one of the freeze points. If thatinformation is later changed, the process may have to be repeated.The change could be a change in manifest or a change to the Orbiterhardware or software. The hardware and software changes in 1985usually were mandatory changes; perhaps some of the manifest changeswere not.

The changes in the manifest were caused byfactors that fall into four general categories: hardware problems,customer requests, operational [**167**] constraints andexternal factors. The significant changes made in 1985 are shown inthe accompanying table. The following examples illustrate that asingle proposed change can have extensive impact, not because thechange itself is particularly difficult to accommodate (though it maybe), but because each change necessitates four or five other changes.The cumulative effect can be substantial. (See the Impact of ManifestChanges chart.)

When a change occurs, the program must choosea response and accept the consequences of that response. The optionsare usually either to maximize the benefit to the customer or tominimize the adverse impact on Space Shuttle operations. If the firstoption is selected, the consequences will include short-term and/orlongterm effects.

Hardware problems can cause extensive changesin the payload manifest. The 51-E mission was on the launch pad, onlydays from launch, with a Tracking and Data Relay Satellite andTelesat satellite in the cargo bay, when a hardware problem in thetracking satellite was discovered. That flight was canceled and thepayload reassigned. The cancellation resulted in major changes toseveral succeeding flights. Mission 51 -D, scheduled to fly twomonths later, was changed to add the Telesat and delete the retrievalof the Long Duration Exposure Facility. The retrieval mission wasthen added to mission 61-I, replacing another satellite. A newmission (61-M) was scheduled for July, 1986, to accommodate theTracking and Data Relay Satellite and the displaced satellite, andall flights scheduled later in 1986 slipped to make room for61-M.

Customers occasionally have notified NASAHeadquarters of a desire to change their scheduled launch datebecause of development problems, financial difficulties or changingmarket conditions. NASA generally accedes to these requests and hasnever imposed the penalties available. An example is the request madeto delay the flight of the Westar satellite from mission 61-C(December, 1985) to a flight in March, 1986. Westar was added toflight 61-E, and the Getaway Special bridge assembly was removed tomake room for it; the HS-376 satellite slot was deleted from 51-L andadded to 61-C; the Spartan-Halley satellite was deleted from 61-D andadded to 51 -L. Thus, four flights experienced major payload changesas a result of one customer's request.

** **

**1985 Changes in the Manifest**

* *

*Hardware Problems*

Tracking and Data Relay Satellite (canceled 51-E, added 61 -M).

Synchronous Communication Satellite (added to61-C).

Synchronous Communication Satellite (removedfrom 61-C).

OV- 102 late delivery from Palmdale (changedto 51 -G, 51 -I, and 61 -A).

* *

*Customer Requests*

HS-376 (removed from 51-I). G-Star (removedfrom 61-C). Satellite Television Corporation-Direct BroadcastSatellite (removed from 61-E).

Westar (removed from 61-C).

Satellite Television Corporation-DirectBroadcast Satellite (removed from 61-H).

Electrophoresis Operations in Space (removedfrom 61-B).

Electrophoresis Operations in Space (removedfrom 61-H).

Hubble Space Telescope (swap with EarthObservation Mission).

* *

*Operational Constraints*

No launch window for Skynet/Indian SatelliteCombination (61-H).

Unacceptable structural loads for Tracking andData Relay Satellite/Indian Satellite (61-H).

Landing weight above allowable limits for eachof the following missions: 61-A, 61-E, 71-A, 61 -K.

* *

*External Factors*

Late addition of SenatorJake Garn (A-Utah) (51-D)

Late addition of Representative Bill Nelson(D-Florida) (61-C).

Late addition of Physical Vapor TransportOrganic Solid experiment (51-I).

** **

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******[**168**]**
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**Graph shows that changes to thepayload manifest for Shuttle missions can boost Johnson Space Centerworkload as much as 130 percent.******
** **

Operational constraints (for example, aconstraint on the total cargo weight) are imposed to insure that thecombination of payloads does not exceed the Orbiter's capabilities.An example involving the Earth Observation Mission Spacelab flight ispresented in the NASA Mission Planning and Operations Team Report inAppendix J. That case illustrates that changes resulting from asingle instance of a weight constraint violation can cascade throughthe entire schedule.

External factors have been the cause of anumber of changes in the manifest as well. The changes discussedabove involve major payloads, but changes to other payloads or topayload specialists can create problems as well. One small changedoes not come alone; it generates several others. A payloadspecialist was added to mission 61-C only two months before itsscheduled lift off. Because there were already seven crew membersassigned to the flight, one had to be removed. The Hughes payloadspecialist was moved from 61-C to 51-L just three months before 51-Lwas scheduled to launch. His experiments were also added to 51-L. Twomiddeck experiments were deleted from 51-L as a result, and thedeleted experiments would have reappeared on later flights.

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******[**169**]**
********
**Graph depicts beginning of simulatortraining for Shuttle crews in days before launch for missions 51-Lthrough 61-K. Launch minus 77 days is normal training datestart.******
** **

Again, a "single" late change affected atleast two flights very late in the planning and preparationcycles.

The effects of such changes in terms ofbudget, cost and manpower can be significant. In some cases, theallocation of additional resources allows the change to beaccommodated with little or no impact to the overall schedule. Inthose cases, steps that need to be re-done can still be accomplishedbefore their deadlines. The amount of additional resources requireddepends, of course, on the magnitude of the change and when thechange occurs: early changes, those before the cargo integrationreview, have only a minimal impact; changes at launch minus fivemonths (two months after the cargo integration review) can carry amajor impact, increasing the required resources by approximately 30percent. In the missions from 41-C to 51-L, only 60 percent of themajor changes occurred before the cargo integration review. More than20 percent occurred after launch minus five months and causeddisruptive budget and manpower impacts.**3**

Engineering flight products are generatedunder a contract that allows for increased expenditures to meetoccasional high workloads.

[**170**] Even with thisbuilt-in flexibility, however, the requested changes occasionallysaturate facilities and personnel capabilities. The strain onresources can be tremendous. For short periods of two to three monthsin mid-1985 and early 1986, facilities and personnel were beingrequired to perform at roughly twice the budgeted flight rate.

If a change occurs late enough, it will havean impact on the serial processes. In these cases, additionalresources will not alleviate the problem, and the effect of thechange is absorbed by all downstream processes, and ultimately by thelast element in the chain. In the case of the flight design andsoftware reconfiguration process, that last element is crew training.In January, 1986, the forecasts indicated that crews on flights after51-I. would have significantly less time than desired to train fortheir flights.**4** (See the Simulation Training chart.)

According to Astronaut HenryHartsfield:

> 
"Had we not had the accident, wewere going to be up against a wall; STS 61-H . . . would have had toaverage 31 hours in the simulator to accomplish their requiredtraining, and STS 61-K would have to average 33 hours. That isridiculous. For the first time, somebody was going to have to standup and say we have got to slip the launch because we are not going tohave the crew trained." **5**

** **

**"Operational" Capabilities**

For a long time during Shuttle development,the program focused on a single flight, the first Space Shuttlemission. When the program became "operational," flights came morefrequently, and the same resources that had been applied to oneflight had to be applied to several flights concurrently.Accomplishing the more pressing immediate requirements divertedattention from what was happening to the system as a whole. Thatappears to be one of the many telling differences between a "researchand development" program and an "operational program." Some of thedifferences are philosophical, some are attitudinal and some arepractical.

Elements within the Shuttle program tried toadapt their philosophy, their attitude and their requirements to the"operational era." But that era came suddenly, and in some cases,there had not been enough preparation for what "operational" mightentail. For example, routine and regular post-flight maintenance andinspections are critical in an operational program; spare parts arccritical to flight readiness in an operational fleet; and thesoftware tools and training facilities developed during a testprogram may not be suitable for the high volume of work required inan operational environment. In many respects, the system was notprepared to meet an "operational" schedule.

As the Space Shuttle system matured, withnumerous changes and compromises, a comprehensive set of requirementswas developed to ensure the success of a mission. What evolved was asystem in which the preflight processing, flight planning, flightcontrol and flight training were accomplished with extreme careapplied to every detail. This process checked and recheckedeverything, and though it was both labor- and time-intensive, it wasappropriate and necessary for a system still in the developmentalphase. This process, however, was not capable of meeting the flightrate goals.

After the first series of flights, the systemdeveloped plans to accomplish what was required to support the flightrate. The challenge was to streamline the processes throughautomation, standardization, and centralized management, and toconvert from the developmental phase to the mature system without acompromise in quality. It required that experts carefully analyzetheir areas to determine what could be standardized and automated,then take the time to do it.

But the increasing flight rate had priority-quality products had to be ready on time. Further, schedules andbudgets for developing the needed facility improvements were notadequate. Only the time and resources left after supporting theflight schedule could be directed toward efforts to streamline andstandardize. In 1985, NASA was attempting to develop the capabilitiesof a production system. But it was forced to do that whileresponding-with the same personnel-to a higher flight rate.

At the same time the flight rate wasincreasing, a variety of factors reduced the number of skilledpersonnel available to deal with it. These included retirements,hiring freezes, transfers to other programs like the Space Stationand transitioning to a single contractor for operationssupport.

[**171**] The flight rate didnot appear to be based on assessment of available resources andcapabilities and was not reduced to accommodate the capacity of thework force. For example, on January 1, 1986, a new contract tookeffect at Johnson that consolidated the entire contractor work forceunder a single company. This transition was another disturbance at atime when the work force needed to be performing at full capacity tomeet the 1986 flight rate. In some important areas, a significantfraction of workers elected not to change contractors. This reducedthe work force and its capabilities, and necessitated intensivetraining programs to qualify the new personnel. According toprojections, the work force would not have been back to full capacityuntil the summer of 1986. This drain on a critical part of the systemcame just as NASA was beginning the most challenging phase of itsflight schedule.**6**

Similarly, at Kennedy the capabilities of theShuttle processing and facilities support work force becameincreasingly strained as the Orbiter turnaround time decreased toaccommodate the accelerated launch schedule. This factor has resultedin overtime percentages of almost 28 percent in some directorates.Numerous contract employees have worked 72 hours per week or longerand frequent 12-hour shifts. The potential implications of suchovertime for safety were made apparent during the attempted launch ofmission 61-C on January 6, 1986, when fatigue and shiftwork werecited as major contributing factors to a serious incident involving aliquid oxygen depletion that occurred less than five minutes beforescheduled lift off. The issue of workload at Kennedy is discussed inmore detail in Appendix G.

Another example of a system designed duringthe developmental phase and struggling to keep up with operationalrequirements is the Shuttle Mission Simulator. There are currentlytwo simulators. They support the bulk of a crew's training forascent, orbit and entry phases of a Shuttle mission. Studies indicatetwo simulators can support no more than 12- 15 flights per year. Theflight rate at the time of the accident was about to saturate thesystem's capability to provide trained astronauts for those flights.Furthermore, the two existing simulator s are out-of-date and requireconstant attention to keep them operating at capacity to meet eventhe rate of 12-15 flights per year. Although there are plans toimprove capability, funds for those improvements are minimal andspread out over a 10-year period. This is another clear demonstrationthat the system was trying to develop its capabilities to meet anoperational schedule but was not given the time, opportunity orresources to do it.**7**

** **

**Responding to Challenges andChanges**

Another obstacle in the path towardaccommodation of a higher flight rate is NASA's legendary "can-do"attitude. The attitude that enabled the agency to put men on the moonand to build the Space Shuttle will not allow it to pass up anexciting challenge-even though accepting the challenge may drainresources from the more mundane (but necessary) aspects of theprogram.

A recent example is NASA's decision to performa spectacular retrieval of two communications satellites whose upperstage motors had failed to raise them to the proper geosynchronousorbit. NASA itself then proposed to the insurance companies who ownedthe failed satellites that the agency design a mission to rendezvouswith them in turn and that an astronaut in a jet backpack fly over toescort the satellites into the Shuttle's payload bay for a return toEarth.

The mission generated considerable excitementwithin NASA and required a substantial effort to develop thenecessary techniques, hardware and procedures. The mission wasconceived, created, designed and accomplished within 10 months. Theresult, mission 51-A (November, 1984), was a resounding success, asboth failed satellites were successfully returned to Earth. Theretrieval mission vividly demonstrated the service that astronautsand the Space Shuttle can perform .

Ten months after the first retrieval mission,NASA launched a mission to repair another communications satellitethat had failed in low-Earth orbit. Again, the mission was developedand executed on relatively short notice and was resoundinglysuccessful for both NASA and the satellite insurance industry.

The satellite retrieval missions were notisolated occurrences. Extraordinary efforts on NASA's part indeveloping and accomplishing missions will, and should, continue, butsuch efforts will be a substantial additional drain on resources.NASA cannot both accept the relatively spur-of [**172**] the-moment missionsthat its "can-do" attitude tends to generate and also maintain theplanning and scheduling discipline required to operate as a "spacetruck" on a routine and cost-effective basis. As the flight rateincreases, the cost in resources and the accompanying impact onfuture operations must be considered when infrequent butextraordinary efforts are undertaken. The system is still notsufficiently developed as a "production line" process in terms ofplanning or implementation procedures. It cannot routinely or evenperiodically accept major disruptions without considerable cost.NASA's attitude historically has reflected the position that "We cando anything," and while that may essentially be true, NASA's optimismmust be tempered by the realization that it cannot doeverything.

NASA has always taken a positive approach toproblem solving and has not evolved to the point where its officialsare willing to say they no longer have the resources to respond toproposed changes. Harold Draughon, manager of the Mission IntegrationOffice at Johnson, reinforced this point by describing what wouldhave to happen in 1986 to achieve the flight rate:

> 
"The next time the guy came in andsaid 'I want to get off this flight and want to move down two' [thesystem would have had to say,] We can't do that,' and that would havebeen the decision." **8**

Even in the event of a hardware problem, afterthe problem is fixed there is still a choice about how to respond.Flight 41-D had a main engine shutdown on the launch pad. It had acommercial payload on it, and the NASA Customer Services divisionwanted to put that commercial payload on the next flight (replacingsome NASA payloads) to satisfy more customers. Draughon described theeffect of that decision to the Commission: "We did that. We did nothave to. And the system went out and put that in work, but it paid aprice. The next three or four flights all slipped as a result."**9**

NASA was being too bold in shufflingmanifests. The total resources available to the Shuttle program for-allocation were fixed. As time went on, the agency had to focus thoseresources more and more on the near term-worrying about today'sproblem and not focusing on tomorrow's.

NASA also did not have a way to forecast theeffect of a change of a manifest. As already indicated, a change toone flight ripples through the manifest and typically necessitateschanges to many other flights, each requiring resources (budget,manpower, facilities) to implement. Some changes are more expensivethan others, but all have an impact, and those impacts must beunderstood.

In fact, Leonard Nicholson, manager of SpaceTransportation System Integration and Operations at Johnson, inarguing for the development of a forecasting tool, illustrated thefact that the resources were spread thin: "The press of businesswould have hindered us getting that kind of tool in place, just thefact that all of us were busy . . . . "**10**

The effect of shuffling major payloads can besignificant. In addition, as stated earlier, even apparently "easy"changes put demands on the resources of the system Any middeck orsecondary payload has, by itself, a minimal impact compared withmajor payloads. But when several changes are made, and made late,they put significant stress on the flight preparation process bydiverting resources from higher priority problems.

Volume III of JSC 07700, Revision B, specifiesthat all middeck experiments must be scheduled, and payloadspecialists assigned, **11** weeks before launch. 11 That rule has not beenenforced-in fact, it is more honored in the breach than in theobservance. A review of missions 41-G through 61-C revealed that ofthe 16 payload specialists added to those flights, seven were addedafter launch minus five months.

Even "secondary" payloads take a lot of timeand attention when they are added to a flight late. HaroldDraughon:

> 
"I spend more than half of my timeworking on things that are not very important because they get put inso late. Rather than working on PAM's [Payload Assist Modules] andIUS's [Inertial Upper Stages], I am working on chicken eggs."**12**

Those directing the changes in the manifestwere not yet sensitive to the problem. Each change nibbles away atthe operational resources, and the changes were occurring frequently,even routinely. Much of the capacity of the system was being used upresponding to late changes in lower priority experiments. Thatflexibility toward secondary experiments tied up the resources thatwould have been better spent building capability to meet theprojected flight rate.

[**173**] Tommy Holloway,chief of the Johnson Flight Director Office, emphasized that, givenfinite resources, one must decide: "It's flight rate versus[manifest] flexibility.'' **l3**

The portion of the system forced to respond tothe late changes in the manifest tried to bring its concerns toHeadquarters. As Mr. Nicholson explained,

> 
"We have done enough complainingabout it that I cannot believe there is not a growing awareness, butthe political aspects of the decision are so overwhelming that ourconcerns do not carry much weight.... The general argument we gaveabout distracting the attention of the team late in the process ofimplementing the flight is a qualitative argument .... And in theface of that, political advantages of implementing those late changesoutweighed our general objections. "**14**

It is important to determine how many flightscan be accommodated, and accommodated safely. NASA must establish arealistic level of expectation, then approach it carefully. Missionschedules should be based on a realistic assessment of what NASA cando safely and well, not on what is possible with maximum effort. Theground rules must be established firmly, and then enforced.

The attitude is important, and the wordoperational can mislead. "Operational" should not imply any lesscommitment to quality or safety, nor a dilution of resources. Theattitude should be, "We are going to fly high risk flights this year;every one is going to be a challenge, and every one is going toinvolve some risk, so we had better be careful in our approach toeach."**15**

** **

**Effect of Flight Rate on SpareParts**

As the flight rate increases, the demand onresources and the demand for spare parts increases. Since 1981, NASAhas had logistics plans for Shuttle flight rates of 12 and 24 flightsa year. It was originally forecast (in mid-1983) that the supply ofspares required to support 12 flights annually could be accomplishedin the spring of 1986. Actual inventory of spare parts had run closeto plan until the second quarter of fiscal year 1985. At that time,inventory requirements for spares began to increase faster thandeliveries. A year later, when inventory stockage should have beencomplete, only 32,000 of the required 50,000 items (65 percent) hadbeen delivered. **16**

The spare parts plan to support 24 flights peryear had called for completing inventory stockage by June, 1987. Bymid-1985, that schedule was in jeopardy.

The logistics plan could not be fullyimplemented because of budget reductions. In October, 1985, thelogistics funding requirement for the Orbiter program, as determinedby Level III management at Johnson, was $285.3 million. That fundingwas reduced by $83.3 million-a cut that necessitated major deferralsof spare parts purchases. Purchasing deferrals come at great cost.For example, a reduction due to deferral of $11.2 million in fiscalyear 1986 would cost $11.2 million in fiscal year 1987, plus anadditional $21.6 million in fiscal year 1988. This three-to-one ratioof future cost to current savings is not uncommon. Indeed, the ratioin many instances is as high as seven to one. This practice cannotmake sense by any standard of good financial management.

According to Johnson officials, reductions inspares expenditures provided savings required to meet the revisedbudgets. As Program Manager Arnold Aldrich reported to theCommission:

> 
"There had been fund contentionsin the program for a number of years, at least starting in themid-seventies and running through into the early to mid-eighties . .. intentional decisions were made to defer the heavy build-up ofspare parts procurements in the program so that the funds could bedevoted to other more pressing activities. . . . It was a regularoccurrence for several annual budget cycles. And once the flight ratereally began to rise and it was really clear that spare parts weregoing to be a problem, significant attention was placed on thatproblem by all levels of NASA and efforts had been made to catch up.But . . . our parts availability is well behind the flight need . .." **17**

Those actions resulted in a critical shortageof serviceable spare components. To provide parts required to supportthe flight rate, NASA had to resort to cannibalization. Extensivecannibalization of spares, i.e., the removal of components[**174**]from one Orbiter for installation in another, became an essentialmodus operandi in order to maintain flight schedules. Forty-five outof approximately 300 required parts were cannibalized for Challengerbefore mission 51-L. These parts spanned the spectrum from commonbolts to a thrust control actuator for the orbital maneuvering systemto a fuel cell. This practice is costly and disruptive, and itintroduces opportunities for component damage.

This concern was summarized in testimonybefore the Commission by Paul Weitz, deputy chief of the AstronautOffice at Johnson:

> 
"It increases the exposure of bothOrbiters to intrusion by people. Every time you get people inside andaround the Orbiter you stand a chance of' inadvertent damage ofwhatever type, whether you leave a tool behind or whether you,without knowing it, step on a wire bundle or a tube or somethingalong those lines." **18**

Cannibalization is a potential threat toflight safety, as parts are removed from one Orbiter, installed inanother Orbiter, and eventually replaced. Each handling introducesanother opportunity for imperfections in installation and for damageto the parts and spacecraft.

Cannibalization also drains resources, as oneKennedy official explained to the Commission on March 5, 1986:

> 
"It creates a large expenditure inmanpower at KSC. A job that you would have normally used what we willcall one unit of' effort to do the job now requires two units ofeffort because you've got two ships [Orbiters] to do the task with."**19**

Prior to the Challenger accident, the shortageof' spare parts had no serious impact on flight schedules, butcannibalization is possible only so long as Orbiters from which toborrow are available. In the spring of 1986, there would have been noOrbiters to use as "spare parts bins." Columbia was to fly in March,Discovery was to be sent to Vandenberg, and Atlantis and Challengerwere to fly in May. In a Commission interview, Kennedy director ofShuttle Engineering Horace Lamberth predicted the program would havebeen unable to continue:

> 
"I think we would have beenbrought to our knees this spring [1986] by this problem [spare parts]if we had kept trying to fly " **20**

NASA's processes for spares provisioning(determining the appropriate spares inventory levels), procurementand inventory control are complicated and could be streamlined andsimplified.

As of spring 1986, the Space Shuttle logisticsprogram was approximately one year behind. Further, the replenishmentof all spares (even parts that are not currently available in thesystem) has been stopped. Unless logistics support is improved, theability to maintain even a three-Orbiter fleet is in jeopardy.

Spare parts provisioning is yet anotherillustration that the Shuttle program was not prepared for anoperational schedule. The policy was shortsighted and led tocannibalization in order to meet the increasing flight rate.

** **

**The Importance of FlightExperience**

In a developmental program it is important tomake use of flight experience, both to understand the system's actualperformance and to uncover problems that might not have beendiscovered in testing. Because Shuttle flights were coming in fairlyrapid succession, it was becoming difficult to analyze all the datafrom one flight before the next was scheduled to launch. In fact, theFlight Readiness Review for 51-L was held while mission 61-C wasstill in orbit. Obviously, it was impossible to even present, muchless analyze and understand, anomalies from that flight.

The point can be emphasized by citing twoproblems that occurred during mission 61-C but were discovered toolate to be considered at the 51-L Flight Readiness Review:

> 
1. The Space Shuttle brakes andtires have long been a source of concern. In particular, after the51-D Orbiter blew a tire at Kennedy in April, 1985, there wasconsiderable effort (within budgetary constraints) to understand andresolve the problems, and Kennedy landings were suspended untilcertain improvements were made. (See section "Landing: AnotherCritical Phase!" page 186.) Mission 51 -L was to be the first flightto land [**175**] in Florida since 51 -D had experienced brakeproblems. STS 61-C landed at Edwards Air Force Base in California onJanuary 19, 1986, four days after the 51-L Flight Readiness Review.The 61-C brakes were removed following landing and shipped to thevendor for further inspection and analysis. That inspection revealedmajor brake damage. The subsystem manager at Johnson in charge of thebrakes did not receive the information until January 27, 1986, oneday before 51-L was launched, and did not learn the extent of theproblem until January 30, 1986.

2. The inspection of the 61 -C Solid RocketBooster segments was completed on January 19, 1986, four days afterthe 51-L Level I Flight Readiness Review. The post-recoveryinspection of the 61 -C Solid Rocket Booster segments revealed thatthere was O-ring erosion in one of the left booster field joints andadditional O-ring anomalies on both booster nozzles. Although theinformation was available for Marshall's 51 -L Level III review atlaunch minus one day, it was clearly not available in time forconsideration in the formal launch preparationprocess.**21** These examples underscore the need to establish a listof mandatory post-flight inspections that must precede any subsequentlaunch.

** **

**Effect on Payload Safety**

The payload safety process exists to ensurethat each Space Shuttle payload is safe to fly and that on a givenmission the total integrated cargo does not create a hazard. NASApolicy is to minimize its involvement in the payload design process.The payload developer is responsible for producing a safe design, andthe developer must verify compliance with NASA safety requirements.The Payload Safety Panel at Johnson conducts a phased series ofsafety reviews for each payload. At those reviews, the payloaddeveloper presents material to enable the panel to assess thepayload's compliance with safety requirements.

Problems may be identified late, however,often as a result of late changes in the payload design and lateinputs from the payload developer. Obviously, the later a hazard isidentified, the more difficult it will be to correct, but the payloadsafety process has worked well in identifying and resolving safetyhazards.

Unfortunately, pressures to maintain theflight schedule may influence decisions on payload safety provisionsand hazard acceptance. This influence was evident in circumstancessurrounding the development of two high priority scientific payloadsand their associated booster, the Centaur.

Centaur is a Space Shuttle-compatible boosterthat can be used to carry heavy satellites from the Orbiter's cargobay to deep space. It was scheduled to fly on two Shuttle missions inMay, 1986, sending the NASA Galileo spacecraft to Jupiter and theEuropean Space Agency Ulysses spacecraft first to Jupiter and thenout of the planets' orbital plane over the poles of the Sun. Thepressure to meet the schedule was substantial because missing launchin May or early June meant a year's wait before planetary alignmentwould again be satisfactory.

Unfortunately, a. number of safety andschedule issues clouded Centaur's use. In particular, Centaur'shighly volatile cryogenic propellants created several problems. If areturn-to-launch-site abort ever becomes necessary, the propellantswill definitely have to be dumped overboard. Continuing safetyconcerns about the means and feasibility of dumping added pressure tothe launch preparation schedule as the program struggled to meet thelaunch dates.

Of four required payload safety reviews,Centaur had completed three at the time of the Challenger accident,but unresolved issues remained from the last two. In November, 1985,the Payload Safety Panel raised several important safety concerns.The final safety review, though scheduled for late January, 1986,appeared to be slipping to February, only three months before thescheduled launches.

Several safety waivers had been granted, andseveral others were pending. Late design changes to accommodatepossible system failure would probably have required reconsiderationof some of the approved waivers. The military version of the Centaurbooster, which was not scheduled to fly for some time, was to bemodified to provide added safety, but because of the rush to get the1986 missions launched, these improvements were not approved for thefirst two Centaur boosters. After the 51-L accident, NASA allottedmore than $75 million to incorporate the [**176**] operational andsafety improvements to these two vehicles.**22** We will never know whether the payload safety programwould have allowed the Centaur missions to fly in 1986. Had theyflown, however, they would have done so without the level ofprotection deemed essential after the accident.

** **

**Outside Pressure to Launch**

After the accident, rumors appeared in thepress to the effect that persons who made the decision to launchmission 51-L might have been subjected to outside pressure to launch.Such rumors concerning unnamed persons, emanating from anonymoussources about events that may never have happened, are difficult todisprove and dispel. Nonetheless, during the Commission's hearingsall persons who played key roles in that decision were questioned.Each one attested, under oath, that there had been no outsideintervention or pressure of any kind leading up to the launch.

There was a large number of other persons whowere involved to a lesser extent in that decision, and they werequestioned. All of those persons provided the Commission with swornstatements that they knew of no outside pressure or intervention.**23**

The Commission and its staff also questioned alarge number of other witnesses during the course of theinvestigation. No evidence was reported to the Commission whichindicated that any attempt was ever made by anyone to apply pressureon those making the decision to launch the Challenger.

Although there was total lack of evidence thatany outside pressure was ever exerted on those who made the decisionto launch 51-L, a few speculative reports persisted.

One rumor was that plans had been made to havea live communication hookup with the 51-L crew during the State ofthe Union Message. Commission investigators interviewed all of thepersons who would have been involved in a hookup if one had beenplanned, and all stated unequivocally that there was no such plan.Furthermore, to give the crew time to become oriented, NASA does notschedule a communication for at least 48 hours after the launch andno such communication was scheduled in the case of flight51-L.

The flight activity officer who wasresponsible for developing the crew activity plan testified thatthree live telecasts were planned for the Challenger, but theyrelated in no way to the State of the Union Message:**24**

- During the teacher activities on flight   day 4. 
- During the phase partitioning experiment   on flight day 5. 
- During the crew conference on flight day   6. 

The Commission concluded that the decision tolaunch the Challenger was made solely by the appropriate NASAofficials without any outside intervention or pressure.

** **

**Findings**

1. The capabilities of the system werestretched to the limit to support the flight rate in winter1985/1986. Projections into the spring and summer of 1986 showed aclear trend; the system, as it existed, would have been unable todeliver crew training software for scheduled flights by thedesignated dates. The result would have been an unacceptablecompression of the time available for the crews to accomplish theirrequired training.

2. Spare parts are in critically short supply.The Shuttle program made a conscious decision to postpone spare partsprocurements in favor of budget items of perceived higher priority.Lack of spare parts would likely have limited flight operations in1986.

3. Stated manifesting policies are notenforced. Numerous late manifest changes (after the cargo integrationreview) have been made to both major payloads and minor payloadsthroughout the Shuttle program.

- Late changes to major payloads or program   requirements can require extensive resources (money, manpower,   facilities) to implement. 
- If many late changes to "minor" payloads   occur, resources are quickly absorbed. 
- Payload specialists frequently were added   to a flight well after announced deadlines. 
- Late changes to a mission adversely affect   the training and development of procedures for subsequent   missions.  

[**177**] 4. The scheduledflight rate did not accurately reflect the capabilities andresources.

- The flight rate was not reduced to   accommodate periods of adjustment in the capacity of the work   force. There was no margin in the system to accommodate unforeseen   hardware problems. 
- Resources were primarily directed toward   supporting the flights and thus not enough were available to   improve and expand facilities needed to support a higher flight   rate. 

5. Training simulators may be the limitingfactor on the flight rate: the two current simulators cannot traincrews for more than 12-15 flights per year.

6. When flights come in rapid succession,current requirements do not ensure that critical anomalies occurringduring one flight are identified and addressed appropriately beforethe next flight. 

** **

**References**

- 1. Hearings of the U.S.   Senate, Subcommittee of the Committee on Appropriations, May 5,   1982, page 1029.    2. Interview with NASA   Administrator James Beggs," Space Business News, September 12,   1983. 
  - 3. See Appendix, NASA   Mission Planning and Operations Team Report (Preliminary), April,   1986, page 86.      4. Commission Work   Session, Mission Planning and Operations Panel, April 1, 1986,   JSC. page 198.
    - 5. Commission Work   Session, Mission Planning and Operations Panel, April 1, 1980,   JSC, page 198.        6. NASA Memo,   DA-RRR-86-06.
      - 7. See Appendix J, NASA   Mission Planning and Operations Team Report (Preliminary), April,   1986, pages 58-59.          8. Commission Work   Session, Mission Planning and Operations Panel, March 24, 1986,   JSC, page 130.
        - 9. Commission Work   Session. Mission Planning and Operations Panel, March 24, 1986,   JSC, page 126.            10. Commission Work   Session, Mission Planning and Operations Panel, April 8, 1986,   JSC, page 240.
          - 11. Page 12.              12. Commission Work   Session, Mission Planning and Operations Panel, April 1, 1986,   JSC, page 205.
            - 13. Commission Work   Session, Mission Planning and Operations Panel, April 8, 1986,   JSC, pages 216-218.                14. Commission Work   Session, Mission Planning and Operations Panel, April 8, 1986,   JSC, pages 216-218.
              - 15. Commission Work   Session, Mission Planning and Operations Panel, April 8, 1986,   JSC, pages 262-263.                  16. NASA Memo from   Goetz, R.. "Logistics Responsibility Transfer from NASA JSC to   NASA KSC," February 6, 1986
                - 17. Commission Hearing   Transcript, April 3, 1986, page 2544.                    18. Commission Hearing   Transcript, April 3, 1986, page 2445.
                  - 19. Commission Work   Session, Mission Planning and Operations Panel, March 5, 1986,   KSC, page 306.                      20. Commission Work   Session, Mission Planning and Operations Panel, March 4, 1986,   KSC, page 304.
                    - 21. Report, "SRM   Post-flight Hardware Inspection Report for STS 61-C," Part 1 of 2,   January 24, 1986, pages 51-52.                        22. Cost figures were   provided by the Centaur program manager, telephone call, May 16,   1986.
                      - 23. Twenty-eight   Affidavits submitted to the Commission.                          24. Commission   Interview Transcript, Ehlers. K., April 16, 1986, JSC, pages   1-10.

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