---

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[82] The decision to
launch the Challenger was flawed. Those who made that decision were
unaware of the recent history of problems concerning the O-rings and
the joint and were unaware of the initial written recommendation of
the contractor advising against the launch at temperatures below 53
degrees Fahrenheit and the continuing opposition of the engineers at
Thiokol after the management reversed its position. They did not have
a clear understanding of Rockwell's concern that it was not safe to
launch because of ice on the pad. If the decisionmakers had known all
of the facts, it is highly unlikely that they would have decided to
launch 51-L on January 28, 1986.



Flaws In The Decision Making
Process

In addition to analyzing all available
evidence concerning the material causes of the accident on January
28, the Commission examined the chain of decisions that culminated in
approval of the launch. It concluded that the decision making process
was flawed in several ways. The actual events that produced the
information upon which the approval of launch was based are recounted
and appraised in the sections of this chapter. The discussion that
follows relies heavily on excerpts from the testimony of those
involved in the management judgments that led to the launch of the
Challenger under conditions described.

That testimony reveals failures in
communication that resulted in a decision to launch 51-L based on
incomplete and sometimes misleading information, a conflict between
engineering data and management judgments, and a NASA management
structure that permitted internal flight safety problems to bypass
key Shuttle managers.

The Shuttle Flight Readiness Review is a
carefully planned, step-by-step activity, established by NASA program
directive SPO-PD 710.5A,1designed to certify the readiness of all components of
the Space Shuttle assembly. The process is focused upon the Level I
Flight Readiness Review, held approximately two weeks before a
launch. The Level I review is a conference chaired by the NASA
Associate Administrator for Space Flight and supported by the NASA
Chief Engineer, the Program Manager, the center directors and project
managers from Johnson, Marshall and Kennedy, along with senior
contractor representatives.

The formal portion of the process is initiated
by directive from the Associate Administrator for Space Flight. The
directive outlines the schedule for the Level I Flight Readiness
Review and for the steps that precede it. The process begins at Level
IV with the contractors formally certifying-in writing-the flight
readiness of the elements for which they are responsible.
Certification is made to the appropriate Level III NASA project
managers at Johnson and Marshall. Additionally, at Marshall the
review is followed by a presentation directly to the Center Director.
At Kennedy the Level III review, chaired by the Center Director,
verifies readiness of the launch support elements.

The next step in the process is the
Certification of Flight Readiness to the Level II Program Manager at
Johnson. In this review each Space Shuttle program element endorses
that it has satisfactorily completed the manufacture,
[83]
assembly, test and checkout of the pertinent element, including the
contractors" certification that design and performance are up to
standard. The Flight Readiness Review process culminates in the Level
I review.

In the initial notice of the review, the Level
I directive establishes a Mission Management Team for the particular
mission. The team assumes responsibility for each Shuttle's readiness
for a period commencing 48 hours before launch and continuing through
post-landing crew egress and the safing of the Orbiter. On call
throughout the entire period, the Mission Management Team supports
the Associate Administrator for Space Flight and the Program
Manager.

A structured Mission Management Team
meeting-called L-1-is held 24 hours, or one day, prior to each
scheduled launch. Its agenda includes closeout of any open work, a
closeout of any Flight Readiness Review action items, a discussion of
new or continuing anomalies, and an updated briefing on anticipated
weather conditions at the launch site and at the abort landing sites
in different parts of the world. It is standard practice of Level-I
and II officials to encourage the reporting of new problems or
concerns that might develop in the interval between the Flight
Readiness Review and the L-1 meeting, and between the L-1 and
launch.

In a procedural sense, the process
described...





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---



[84]....was followed in
the case of flight 51 -L. However, in the launch preparation for 51-L
relevant concerns of Level III NASA personnel and element contractors
were not, in the following crucial areas, adequately communicated to
the NASA Level I and II management responsible for the launch:

- The objections to launch voiced by Morton
   Thiokol c engineers about the detrimental effect of cold
   temperatures on the performance of' the Solid Rocket Motor joint
   seal.
- The degree of concern of Thiokol and
   Marshall about the erosion of the joint seals in prior Shuttle
   flights, notably 51-C (January, 1985) and 51-B (April,
   1985).

On December 13, 1985, the Associate
Administrator for Space flight, Jesse Moore, sent out a message
distributed among NASA Headquarters, NASA field centers, and U.S. Air
Force units, that scheduled the Flight Readiness Review for January
15, 1986, and prescribed the dates for the other steps in the
standard procedure.

The message was followed by directives from
James A. (Gene) Thomas, Deputy Director of Launch and Landing
Operations at Kennedy on January 2, 1986; by the National Space
Transportation System Program Manager, Arnold Aldrich, on January 3;
by William R. Lucas, the Marshall Center Director, on January 7; and
by the Marshall Shuttle Projects Office on January 8. Each of these
implementing directives prescribed for Level III the preparatory
steps for the Flight Readiness Review.

The Flight Readiness Review was held, as
scheduled, on January 15. On the following day, Aldrich issued the
schedule for the combined Level I/Mission Management Team meetings;
he also announced plans for the Mission Management Team meetings
continuing throughout the mission and included the schedule for the
L-1 review.

On January 23, Moore issued a directive
stating that the Flight Readiness Review had been conducted on the
15th and that 51-L was ready to fly pending closeout of open work,
satisfactory countdown, and completion of remaining Flight Readiness
Review action items, which were to be closed out during the L-1
meeting. No problems with the Solid Rocket Booster were
identified.

Since December, 1982, the O-rings had been
designated a "Criticality 1" feature of the Solid...





---





---



....Rocket Booster design, a term denoting a
failure point-without back-up-that could cause a loss of 'life or
vehicle if' the component fails. In July 1985, after a nozzle joint
on STS 51-B showed erosion of a secondary O-ring, indicating that the
primary seal failed, a launch constraint was placed on flight 51-F
and subsequent launches. These constraints had been imposed and
regularly waived by the Solid Rocket Booster Project Manager at
Marshall, Lawrence B. Mulloy.

Neither the launch constraint, the reason for
it, or the six consecutive waivers prior to 51-L were known to Moore
(Level I) or Aldrich (Level II) or Thomas at the time of the Flight
Readiness Review process for 51-L.

It should be noted that there were other and
independent paths of system reporting that were designed to bring
forward information about the Solid Rocket Booster joint anomalies.
One path was the task force of Thiokol engineers and [85] Marshall engineers
who had been conducting subscale pressure tests at Wasatch during
1985, a source of documented rising concern and frustration on the
part of some of the Thiokol participants and a few of the Marshall
participants. But Level II was not in the line of reporting for this
activity. Another path was the examination at each Flight Readiness
Review of evidence of earlier flight anomalies. For 51-L, the data
presented in this latter path, while it reached Levels I and II,
never referred to either test anomalies or flight anomalies with
O-rings.

In any event, no mention of the O-ring
problems in the Solid Rocket Booster joint appeared in the
Certification of Flight Readiness, signed for Thiokol on January 9,
1986, by Joseph Kilminster, for the Solid Rocket Booster set
designated BI026.2

Similarly, no mention appeared in the
certification endorsement, signed on January 15, 1986, by Kilminster
and by Mulloy,3No mention appears in several inches of paper
comprising the entire chain of readiness reviews for
51-L.4

In the 51-L readiness reviews, it appears that
neither Thiokol management nor the Marshall Level III project
managers believed that the O-ring blow-by and erosion risk was
critical. The testimony and contemporary correspondence show that
Level III believed there was ample margin to fly with O-ring erosion,
provided the leak check was performed at 200 pounds per square
inch.

Following the January 15 Flight Readiness
Review each element of the Shuttle was certified as
flight-ready.

The L- 1 Mission Management Team meeting took
place as scheduled at 11:00 a.m. Eastern Standard Time January 25. No
technical issues appeared at this meeting or in the documentation and
all Flight Readiness Review actions were reported closed out.

Mr. Mulloy testified as follows regarding the
Flight Readiness Review record about O-ring concerns:5



> Chairman Rogers: . . . Why wasn't that a cause for concern on the part
> of the whole NASA organization?
> 
> Mr. Mulloy:It was cause for concern, sir.
> 
> Chairman Rogers: Who did you tell about this?
> 
> Mr. Mulloy:
> Everyone, sir.
> 
> Chairman Rogers: And they all knew about it at the time of
> 51-L?
> 
> Mr. Mulloy:
> Yes, sir. You will find in the Flight Readiness Review record that
> went all the way to the L-1 review.



It is disturbing to the Commission that
contrary to the testimony of the Solid Rocket Booster Project
Manager, the seriousness of concern was not conveyed in Flight
Readiness Review to Level I and the 51-L readiness review was
silent.

The only remaining issue facing the Mission
Management Team at the L-1 review was the approaching cold front,
with forecasts of rain showers and temperatures in the mid-sixties.
There had also been heavy rain since 51-L had been rolled out to the
launch pad, approximately seven inches compared with the 2.5 inches
that would have been normal for that season and length of exposure
(35 days).

At 12:36 p.m. on the 27th, the Mission
Management Team scrubbed the launch for that day due to high cross
winds at the launch site. In the accompanying discussion that ran for
about half an hour, all appropriate personnel were polled as to the
feasibility of a launch within 24 hours. Participants were requested
to identify any constraints. This meeting, aimed at launch at 9:38
a.m. On January 28, produced no constraints or concerns about the
performance of the Solid Rocket Boosters.

At 2:00 p.m. on the 27th, the Mission
Management Team met again. At that time, the weather was expected to
clear, but it appeared that temperatures would be in the low twenties
for about 11 hours. Issues were raised with regard to the cold
weather effects on the launch facility, including the water drains,
the eye wash and shower water, fire suppression system, and
overpressure water trays. It was decided to activate heaters in the
Orbiter, but no concerns were expressed about the O-rings in the
Solid Rocket Boosters. The decision was to proceed with the countdown
and with fueling, but all members of the team were asked to review
the situation and call if any problems arose.

At approximately 2:30 p.m. EST, at Thiokol's
Wasatch plant, Robert Ebeling, after learning of the predicted low
temperature for launch, convened a meeting with Roger Boisjoly and
with other Thiokol engineers. A brief chronology of the subsequent
chain of events begins on page 104. Ebeling was concerned about
predicted cold [86] temperatures at Kennedy Space Center. In a
post-accident interview, Mr. Ebeling recalled the substance of the
meeting.6

> "The meeting lasted one hour, but
> the conclusion of that meeting was Engineering-especially Arnie,
> Roger Boisjoly, Brian Russell, myself, Jerry Burns, they come to
> mind-were very adamant about their concerns on this lower
> temperature, because we were way below our data base and we were way
> below what we qualified for."

Later in the afternoon on the same day, Allan
McDonald-Thiokol's liaison for the Solid Rocket Booster project at
Kennedy Space Center- received a telephone call from Ebeling,
expressing concern about the performance of the Solid Rocket Booster
field joints at low temperatures. During testimony before the
Commission on February 27, McDonald recounted that
conversation:7



> Mr. McDonald: Well, I had first become aware of the concern of the
> low temperatures that were projected for the Cape, it was late in the
> afternoon of the 27th. I was at Carver Kennedy's house. He is a vice
> president of, as I mentioned, our space operations center at the
> Cape, and supports the stacking of the SRMs [Solid Rocket
> Motors].
> 
> And I had a call from Bob Ebeling. He is the
> manager of our ignition system an final assembly, and he worked for
> me as program manager at Thiokol in Utah. And he called me and said
> that they had just received some word earlier that the weatherman was
> projecting temperatures as low as 18 degrees Fahrenheit some time in
> the early morning hours of the 28th, and that they had some meetings
> with some of the engineering people and had some concerns about the
> O-rings getting to those kinds of temperatures.
> 
> And he wanted to make me aware of that and
> also wanted to get some more updated and better information on what
> the actual temperature was going to be depicted, so that they could
> make some calculations on what they expected the real temperature the
> O-rings may see....
> 
> I told him that I would get that temperature
> data for him and call him back. Carver Kennedy then, when I hung up,
> called the launch operations center to get the predicted temperatures
> from pad B, as well as what the temperature history had been during
> the day up until that time.
> 
> . . . He obtained those temperatures from the
> launch operations center, and they basically said that they felt it
> was going to get near freezing or freezing before midnight. It would
> get as low as 22 degrees as a minimum in the early morning hours,
> probably around 6:00 o'clock, and that they were predicting a
> temperature of about 26 degrees at the intended time, about 9:38 the
> next morning.
> 
> I took that data and called back to the plant
> and sent it to Bob Ebeling and relayed that to him, and told him he
> ought to use this temperature data for his predictions, but I thought
> this was very serious and to make sure that he had the vice
> president, engineering, involved in this and all of his people; that
> I wanted them to put together some calculations and a presentation of
> material.
> 
> Chairman Rogers: Who's the Vice President, Engineering?
> 
> Mr. McDonald: Mr. Bob Lund is our Vice President, Engineering, at
> our Morton Thiokol facility in Utah.
> 
> To make sure he was involved in this, and that
> this decision should be an engineering decision, not a program
> management decision. And I told him that I would like him to make
> sure they prepared some charts and were in a position to recommend
> the launch temperature and to have the rationale for supporting that
> launch temperature.
> 
> I then hung up and I called Mr. Mulloy. He was
> staying at the Holiday Inn in Merritt Island and they couldn't reach
> him, and so I called Cecil Houston-Cecil Houston is the resident
> manager for the Marshall Space Flight Center office at KSC [Kennedy
> Space Center]-and told him about our concerns with the low
> temperatures and the potential problem with the O-rings.
> 
> And he said that he would set up a
> teleconference. He had a four-wire system next to his office. His
> office is right across from the VAB [Vehicle Assembly Building] in
> the trailer complex C over there. And he would set up a four-wire
> teleconference involving the engineering people at Marshall Space
> Flight Center at Huntsville, our people back at Thiokol in Utah; and
> that I [87]should come down to his office and participate at
> Kennedy from there, and that he would get back with me and let me
> know when that time would be.



Soon thereafter Cecil Houston called Dr.
Judson Lovingood, Deputy Shuttle Project Manager at Marshall Space
Flight Center, to inform him of the concerns about the O-rings and
asked Lovingood to set up a teleconference with senior project
management personnel, with George Hardy, Marshall's Deputy Director
of Science and Engineering, and with Morton Thiokol personnel.
Lovingood called Stanley Reinartz, Shuttle Project Manager, a few
minutes later and informed him of the planned telecon.

The first phase of the teleconference began at
5:45 p. m. Eastern Standard Time; participants included Reinartz,
Lovingood, Hardy, and numerous people at Kennedy, Marshall and
Thiokol-Wasatch. (Allen McDonald missed this phase; he did not arrive
at Kennedy until after 8:00 p.m.) Concerns for the effect of low
temperature on the O-rings and the joint seal were presented by
Morton Thiokol, along with an opinion that launch should be delayed.
A recommendation was also made that Aldrich, Program Manager at
Johnson (Level II), be informed of these concerns.

The following are excerpts from testimony
before the Commission relating to the teleconference:8



> Dr. Keel: You just indicated earlier that, based upon that
> teleconference, you thought there was a good possibility of delay. Is
> that what Thiokol was recommending then, was delay?
> 
> Dr. Lovingood: That is the way I heard it, and they were talking
> about the 51-C experience and the fact that they had experienced the
> worst case blow-by as far as the arc and the soot and so forth. And
> also, they talked about the resiliency data that they had.
> 
> So it appeared to me-and we didn't have all of
> the proper people there. That was another aspect of this. It appeared
> to me that we had better sit down and get the data so that we could
> understand exactly what they were talking about and assess that
> data.
> 
> And that is why I suggested that we go ahead
> and have a telecon within the center, so that we could review
> that.
> 
> Dr. Keel: So
> as early as after that first afternoon conference at 5:45, it
> appeared that Thiokol was basically saying delay. Is that
> right?
> 
> Dr. Lovingood: That is the way it came across to me. I don't know
> how other people perceived it, but that's the way it came across to
> me.
> 
> Dr. Keel:
> Mr. Reinartz, how did you perceive It?
> 
> Mr. Reinartz: I did not perceive it that way. I perceived that they
> were raising some questions and issues which required looking into by
> all the right parties, but I did not perceive it as a recommendation
> delay.
> 
> Dr. Keel:
> Some prospects for delay?
> 
> Mr. Reinartz: Yes, sir, that possibility is always there.
> 
> Dr. Keel:
> Did you convey that to Mr. Mulloy and Mr. Hardy before the 8:15
> conference?
> 
> Mr. Reinartz: Yes, I did. And as a matter of fact, we had a
> discussion. Mr. Mulloy was just out of communication for about an
> hour, and then after that I got in contact with him, and we both had
> a short discussion relating to the general nature of the concerns
> with Dr. Lucas and Mr. Kingsbury at the motel before we both departed
> for the telecon that we had set up out at the Cape.
> 
> Dr. Keel:
> But based upon that, Mr. Lovingood, that impression, you thought it
> was a significant enough possibility that Mr. Aldrich should have
> been contacted?
> 
> Dr. Lovingood: Yes.
> 
> Dr. Keel: In
> addition, did you recommend that Mr. Lucas, who is director of
> Marshall, of course, and Mr. Kingsbury, who is Mr. Hardy's boss,
> participate in the 8:15 conference?
> 
> Dr. Lovingood:Yes, I did.
> 
> Dr. Keel:
> And you recommended that to whom?
> 
> Dr. Lovingood: I believe I said that over the net. I said that I
> thought we ought to have an inter-center meeting involving Dr. Lucas
> and Mr. Kingsbury, and then plan to go on up the line to Level II and
> Level I.
> 
> And then it was after we broke off that first
> telecon I called Stan at the motel and told [88] him that he ought to
> go ahead and alert Arnie to that possibility.
> 
> Dr. Keel:
> And Mr. Reinartz, you then visited the motel room of Mr. Lucas with
> Mr. Kingsbury, and also was Mr. Mulloy with you then?
> 
> Mr. Reinartz: Yes, sir, he was. In the first couple of minutes I
> believe I was there by myself, and then Mr. Mulloy joined us.
> 
> Dr. Keel:
> And did you discuss with them Mr. Lovingood's recommendation that the
> two of them, Lucas and Kingsbury, participate?
> 
> Mr. Reinartz: No, sir. I don't recall discussing Mr. Lovingood's
> recommendations. I discussed with them the nature of the telecon, the
> nature of the concerns raised by Thiokol, and the plans to gather the
> proper technical support people at Marshall for examination of the
> data. And I believe that was the essence of the discussion.
> 
> Chairman Rogers: But you didn't recommend that the information be
> given to Level II or Level I?
> 
> Mr. Reinartz: I don't recall that I raised that issue with Dr.
> Lucas. I told him what the plans were for proceeding. I don't recall,
> Mr. Chairman, making any statement regarding that.
> 
> Mr. Hotz:
> Mr. Reinartz, are you telling us that you in fact are the person who
> made the decision not to escalate this to a Level II item?
> 
> Mr. Reinartz: That is correct, sir.



At approximately 8:45 p.m. Eastern Standard
Time, Phase 2 of the teleconference commenced, the Thiokol charts and
written data having arrived at Kennedy Space Center by telefax. (A
table of teleconference participants is included with Chronology of
Events.) The charts presented a history of the O-ring erosion and
blow-by in the Solid Rocket Booster joints of previous flights,
presented the results of subscale testing at Thiokol and the results
of static tests of Solid Rocket Motors. In the following testimony,
Roger Boisjoly, Allan McDonald and Larry Mulloy expressed their
recollections of this teleconference up to the point when an off-net
caucus was requested:9



> Mr. Boisjoly:I expressed deep concern about launching at low
> temperature. I presented Chart 2-1 with emphasis-now, 2-1, if you
> want to see it, I have it, but basically that was the chart that
> summarized the primary concerns, and that was the chart that I pulled
> right out of the Washington presentation without changing one word of
> it because it was still applicable, and it addresses the highest
> concern of the field joint in both the ignition transient condition
> and the steady state condition, and it really sets down the rationale
> for why we were continuing to fly. Basically, if erosion penetrates
> the primary O-ring seal, there is a higher probability of no
> secondary seal capability in the steady state condition. And I had
> two sub-bullets under that which stated bench testing showed O-ring
> not capable of maintaining contact with metal parts, gap, opening
> rate to maximum operating pressure. I had another bullet which stated
> bench testing showed capability to maintain O-ring contact during
> initial phase (0 to 170 milliseconds of transient). That was my
> comfort basis of continuing to fly under normal circumstances, normal
> being within the data base we had.
> 
> I emphasized, when I presented that chart
> about the changing of the timing function of the O-ring as it
> attempted to seal. I was concerned that we may go from that first
> beginning region into that intermediate region, from O to 170 being
> the first region, and 170 to 330 being the intermediate region where
> we didn't have a high probability of sealing or seating.
> 
> I then presented Chart 2-2 with added concerns
> related to the timing function. And basically on that chart, I
> started off talking about a lower temperature than current data base
> results in changing the primary O-ring sealing timing function, and I
> discussed the SRM-15 [Flight 51-C, January, 1985] observations,
> namely, the 15A [Left SRM, Flight 51-C] motor had 80 degrees arc
> black grease between the O-rings, and make no mistake about it, when
> I say black, I mean black just like coal. It was jet black. And
> SRM-15B [Right SRM, Flight 51-C] had a 110 degree arc of black grease
> between the O-rings. We would have low O-ring squeeze due to
> low.....





---







---



> [89] ....temperature
> which I calculated earlier in the day. We should have higher O-ring
> Shore hardness.
> 
> Now, that would be harder. And what that
> material really is, it would be likened to trying to shove a brick
> into a crack versus a sponge. That is a good analogy for purposes of
> this discussion. I also mentioned that thicker grease, as a result of
> lower temperatures, would have a higher viscosity. It wouldn't be as
> slick and slippery as it would be at room temperature. And so it
> would be a little bit more difficult to move across it.
> 
> We would have higher O-ring pressure actuation
> time, in my opinion, and that is what I presented.... These are the
> sum and substance of what I just presented. If action time increases,
> then the threshold of secondary seal pressurization capability is
> approached. That was my fear. If the threshold is reached, then
> secondary seal may not be capable of being pressurized, and that was
> the bottom line of everything that had been presented up to that
> point.
> 
> Chairman Rogers: Did anybody take issue with you?
> 
> Mr. Boisjoly: Well, I am coming to that. I also showed a chart of
> the joint with an exaggerated cross section to show the seal lifted
> off, which has been shown to everybody. I was asked, yes, at that
> point in time I was asked to quantify my concerns, and I said I
> couldn't. I couldn't quantify it. I had no data to quantify it, but I
> did say I knew that it was away from goodness in the current data
> base. Someone on the net commented that we had soot blow-by on SRM-22
> [Flight 61-A, October, 1985] which was launched at 75 degrees. I
> don't remember who made the comment, but that is where the first
> comment came in about the disparity between my conclusion and the
> observed data because SRM-22 [Flight 61-A, October, 1985] had blow-by
> at essentially a room temperature launch.
> 
> I then said that SRM-15 [Flight 51-C, January,
> 1985] had much more blow-by indication and that it was indeed telling
> us that lower temperature was a factor. This was supported by
> inspection of flown hardware by myself. I was asked again for data to
> support my claim, and I said I have none other than what is being
> presented, and I had been trying to get resilience data, Arnie and I
> both, since last October, and that statement was mentioned on the
> net.
> 
> Others in the room presented their charts, and
> the main telecon session concluded with Bob Lund, who is our Vice
> President of....





---





---



> [90] ....Engineering,
> presenting his conclusions and recommendations charts which were
> based on our data input up to that point. Listeners on the telecon
> were not pleased with the conclusions and the recommendations.
> 
> Chairman Rogers: What was the conclusion ?
> 
> Mr. Boisjoly: The conclusion was we should not fly outside of our
> data base, which was 53 degrees. Those were the conclusions. And we
> were quite pleased because we knew in advance, having participated in
> the preparation, what the conclusions were, and we felt very
> comfortable with that.
> 
> Mr. Acheson:
> Who presented that conclusion?
> 
> Mr. Boisjoly: Mr. Bob Lund. He had prepared those charts. He had
> input from other people. He had actually physically prepared the
> charts. It was about that time that Mr. Hardy from Marshall was asked
> what he thought about the MTI [Morton Thiokol] recommendation, and he
> said he was appalled at the MTI decision. Mr. Hardy was also asked
> about launching, and he said no, not if the contractor recommended
> not launching, he would not go against the contractor and
> launch.
> 
> There was a short discussion that ensued about
> temperature not being a discriminator between SRM-15 [Flight 51-C]
> and SRM-22 [Flight 61-A], and shortly after, I believe it was Mr.
> Kilminster asked if- excuse me. I'm getting confused here. Mr.
> Kilminster was asked by NASA if he would launch, and he said no
> because the engineering recommendation was not to launch.
> 
> Then MTI management then asked for a
> five-minute caucus. I'm not sure exactly who asked for that, but it
> was asked in such a manner that I remember it was asked for, a
> five-minute caucus, which we put on- the line on mute and went
> off-line with the rest of the net.
> 
> Chairman Rogers: Mr. Boisjoly, at the time that you made the-that
> Thiokol made the recommendation not to launch, was that the unanimous
> recommendation as far as you knew?
> 
> Mr. Boisjoly: Yes. I have to make something clear. I have been
> distressed by the things that have been appearing in the paper and
> things that have been said in general, and there was never one
> positive, pro-launch statement ever made by anybody. There have been
> some feelings since then that folks have expressed that they would
> support the decision, but there was not one positive statement for
> launch ever made in that room.



Mr. McDonald's testimony:10



> Mr. McDonald: I arrived at the Kennedy Space Center at about 8:15
> [p.m.], and when I arrived there at the Kennedy Space Center the
> others that had already arrived were Larry Mulloy, who was there-he
> is the manager, the project manager for the SRB for Marshall. Stan
> Reinartz was there and he is the manager of the Shuttle Project
> Office. He's Larry Mulloy's boss.
> 
> Cecil Houston was there, the resident manager
> for Marshall. And Jack Buchanan was there. He happens to be our
> manager, Morton Thiokol's manager of our launch support services
> office at Kennedy.
> 
> The telecon hadn't started yet. It came on
> [91] the
> network shortly after I got there. .
> 
> Chairman Rogers: Was it essentially a telephone conference or was
> there actually a network of pictures?
> 
> Mr. McDonald: It was a telephone conference....
> 
> But I will relay . . . what I heard at the
> conference as best I can. The teleconference started I guess close to
> 9:00 o'clock and, even though all the charts weren't there, we were
> told to begin and that Morton Thiokol should take the lead and go
> through the charts that they had sent to both centers.
> 
> The charts were presented by the engineering
> people from Thiokol, in fact by the people that had made those
> particular charts. Some of them were typed, some of them were
> handwritten. And they discussed their concerns with the low
> temperatures relative to the possible effects on the O-rings,
> primarily the timing function to seal the 0rings.
> 
> They presented a history of some of the data
> that we had accumulated both in static test and in flight tests
> relative to temperatures and the performance of the 0rings, and
> reviewed the history of all of our erosion studies of the O-rings, in
> the field joints, any blow-by of the primary O-ring with soot or
> products of combustion or decomposition that we had noted, and the
> performance of the secondary O-rings.
> 
> And there was an exchange amongst the
> technical people on that data as to what it meant . . . But the real
> exchange never really came until the conclusions and recommendations
> came in.
> 
> At that point in time, our vice president, Mr.
> Bob Lund, presented those charts and he presented the charts on the
> conclusions and recommendations. And the bottom line was that the
> engineering people would not recommend a launch below 53 degrees
> Fahrenheit. The basis for that recommendation was primarily our
> concern with the launch that had occurred about a year earlier, in
> January of 1985, I believe it was 51-C.



Mr. Mulloy's testimony:11



> Mr. Mulloy: That telecon was a little late starting. It was
> intended to be set up at 8:15 . . . and the telecon was begun at
> 8:45.
> 
> And Thiokol will then present to you today the
> data that they presented to us in that telecon. I will not do that.
> The bottom line of that, though, initially was that Thiokol
> engineering, Bob Lund, who is the Vice President and Director of
> Engineering, who is here today, recommended that 51-L not be launched
> if the O-ring temperatures predicted at launch time would be lower
> than any previous launch, and that was 53 degrees.
> 
> Dr. Walker:
> May I ask a question? I wish you would distinguish between the
> predicted bulk temperatures and the O-ring temperatures. In fact, as
> I understand it, you really don't have any official O-ring
> temperature prediction in your models, and it seems that the
> assumption has been that the O-ring temperature is the same as the
> bulk temperature, which we know is not the case.
> 
> Mr. Mulloy:
> You will see, sir, in the Thiokol presentation today that that is not
> the case. This was a specific calculation of what the O-ring
> temperature was on the day of the January 1985 launch. It is not the
> bulk temperature of the propellant, nor is it the ambient temperature
> of the air.
> 
> It was Thiokol's calculation of what the
> lowest temperature an O-ring had seen in previous flights, and the
> engineering recommendation was that we should not move outside of
> that experience base.
> 
> I asked Joe Kilminster, who is the program
> manager for the booster program at Thiokol, what his recommendation
> was, because he is the gentleman that I get my recommendations from
> in the program office. He stated that, based on that engineering
> recommendation, that he could not recommend launch.
> 
> At that point I restated, as I have testified
> to, the rationale that was essentially documented in the 1982
> Critical Items List, that stated that the rationale had been that we
> were flying with a simplex joint seal. And you will see in the
> Thiokol presentation that the context of their presentation is that
> the primary ring, with the reduced temperatures and reduced
> resiliency, may not function as [92] a primary seal and
> we would be relying on secondary.
> 
> And without getting into their rationale and
> getting ahead, the point, the bottom line, is that we were
> continuing-the assessment was, my assessment at that time was, that
> we would have an effective simplex seal, based upon the engineering
> data that Thiokol had presented, and that none of those engineering
> data seemed to change that basic rationale.
> 
> Stan Reinartz then asked George Hardy, the
> Deputy Director of Science and Engineering at Marshall, what his
> opinion was. George stated that he agreed that the engineering data
> did not seem to change this basic rationale, but also stated on the
> telecon that he certainly would not recommend launching if Thiokol
> did not.
> 
> At that time Joe Kilminster requested a five
> minute off-net caucus, and that caucus lasted approximately 30
> minutes.



The teleconference was recessed at
approximately 10:30 p.m. Eastern Standard Time. The off-net caucus of
Thiokol personnel started and continued for about 30 minutes at the
Wasatch office. The major issues, according to the testimony of Jerry
Mason, Senior Vice President for Wasatch Operations, were the effect
of temperature upon the O-rings and the history of erosion of the
O-rings:12



> Mr. Mason: Now, in the caucus we revisited all of our previous
> discussions, and the important things that came out of that was that,
> as we had recognized, we did have the possibility that the primary
> O-ring might be slower to move into the seating position and that was
> our concern, and that is what we had focused on originally.
> 
> The fact that we couldn't show direct
> correlation with the O-ring temperature was discussed, but we still
> felt that there was some concern about it being colder.
> 
> We then recognized that, if the primary did
> move more slowly, that we could get some blow-by and erosion on the
> primary. But we had pointed out to us in that caucus a point that had
> not come across clearly in our earlier discussions, and that is that
> we had run tests where we deliberately cut large pieces out of the
> O-rings to see what the threshold of sealing was, and we found we
> could go to 125 thousandths of a cut out of the O-ring and it would
> still seal.

Approximately 10 engineers participated in the
caucus, along with Mason, Kilminster, C. G. Wiggins (Vice President,
Space Division), and Lund. Arnold Thompson and Boisjoly voiced very
strong objections to launch, and the suggestion in their testimony
was that Lund was also reluctant to launch:13



> Mr. Boisjoly: Okay, the caucus started by Mr. Mason stating a
> management decision was necessary. Those of us who opposed the launch
> continued to speak out, and I am specifically speaking of Mr.
> Thompson and myself because in my recollection he and I were the only
> ones that vigorously continued to oppose the launch. And we were
> attempting to go back and rereview and try to make clear what we were
> trying to get across, and we couldn't understand why it was going to
> be reversed. So we spoke out and tried to explain once again the
> effects of low temperature. Arnie actually got up from his position
> which was down the table, and walked up the table and put a quarter
> pad down in front of the table, in front of the management folks, and
> tried to sketch out once again what his concern was with the joint,
> and when he realized he wasn't getting through, he just
> stopped.
> 
> I tried one more time with the photos. I
> grabbed the photos, and I went up and discussed the photos once again
> and tried to make the point that it was my opinion from actual
> observations that temperature was indeed a discriminator and we
> should not ignore the physical evidence that we had observed .
> 
> And again, I brought up the point that SRM- 15
> [Flight 51 -C, January, 1985] had a 110 degree arc of black grease
> while SRM-22 [Flight 61-A, October, 1985] had a relatively different
> amount, which was less and wasn't quite as black. I also stopped when
> it was apparent that I couldn't get anybody to listen.
> 
> Dr. Walker:
> At this point did anyone else speak up in favor of the launch?
> 
> Mr. Boisjoly: No, sir. No one said anything, in my recollection,
> nobody said a word. It was then being discussed amongst the
> management folks. After Arnie and I had [93] our last say, Mr.
> Mason said we have to make a management decision. He turned to Bob
> Lund and asked him to take off his engineering hat and put on his
> management hat. From this point on, management formulated the points
> to base their decision on. There was never one comment in favor, as I
> have said, of launching by any engineer or other nonmanagement person
> in the room before or after the caucus. I was not even asked to
> participate in giving any input to the final decision charts.
> 
> I went back on the net with the final charts
> or final chart, which was the rationale for launching, and that was
> presented by Mr. Kilminster. It was hand written on a notepad, and he
> read from that notepad. I did not agree with some of the statements
> that were being made to support the decision. I was never asked nor
> polled, and it was clearly a management decision from that
> point.
> 
> I must emphasize, I had my say, and I never
> [would] take [away] any management right to take the input of an
> engineer and then make a decision based upon that input, and I truly
> believe that. I have worked at a lot of companies, and that has been
> done from time to time, and I truly believe that, and so there was no
> point in me doing anything any further than I had already attempted
> to do.
> 
> I did not see the final version of the chart
> until the next day. I just heard it read. I left the room feeling
> badly defeated, but I felt I really did all I could to stop the
> launch.
> 
> I felt personally that management was under a
> lot of pressure to launch and that they made a very tough decision,
> but I didn't agree with it.
> 
> One of my colleagues that was in the meeting
> summed it up best. This was a meeting where the determination was to
> launch, and it was up to us to prove beyond a shadow of a doubt that
> it was not safe to do so. This is in total reverse to what the
> position usually is in a preflight conversation or a flight readiness
> review. It is usually exactly opposite that.
> 
> Dr. Walker:
> Do you know the source of the pressure on management that you alluded
> to?
> 
> Mr. Boisjoly: Well, the comments made over the [net] is what I
> felt, I can't speak for them, but I felt it-I felt the tone of the
> meeting exactly as I summed up, that we were being put in a position
> to prove that we should not launch rather than being put in the
> position and prove that we had enough data to launch. And I felt that
> very real.
> 
> Dr. Walker:
> These were the comments from the NASA people at Marshall and at
> Kennedy Space Center? Mr. Boisjoly: Yes. Dr. Feynman: I take it you
> were trying to find proof that the seal would fail?
> 
> Mr. Boisjoly: Yes.
> 
> Dr. Feynman:
> And of course, you didn't, you couldn't, because five of them didn't,
> and if you had proved that they would have all failed, you would have
> found yourself incorrect because five of them didn't fail.
> 
> Mr. Boisjoly: That is right. I was very concerned that the cold
> temperatures would change that timing and put us in another regime,
> and that was the whole basis of my fighting that night.



As appears from the foregoing, after the
discussion between Morton Thiokol management and the engineers, a
final management review was conducted by Mason, Lund, Kilminster, and
Wiggins. Lund and Mason recall this review as an unemotional,
rational discussion of the engineering facts as they knew them at
that time; differences of opinion as to the impact of those facts,
however, had to be resolved as a judgment call and therefore a
management decision. The testimony of Lund taken by Commission staff
investigators is as follows:14



> Mr. Lund: We tried to have the telecon, as I remember it was
> about 6:00 o'clock [MST], but we didn't quite get things in order,
> and we started transmitting charts down to Marshall around 6:00 or
> 6:30 [MST], something like that, and we were making charts in real
> time and seeing the data, and we were discussing them with the
> Marshall folks who went along.
> 
> We finally got the-all the charts in, and when
> we got all the charts in I stood at the board and tried to draw the
> conclusions that we had out of the charts that had been presented,
> and we came up with a conclusions [94] chart and said that
> we didn't feel like it was a wise thing to fly.
> 
> Question:
> What were some of the conclusions?
> 
> Mr. Lund: I
> had better look at the chart. Well, we were concerned the temperature
> was going to be lower than the 50 or the 53 that had flown the
> previous January, and we had experienced some blow-by, and so we were
> concerned about that, and although the erosion on the O-rings, and it
> wasn't critical, that, you know, there had obviously been some little
> puff go through. It had been caught.
> 
> There was no real extensive erosion of that
> O-ring, so it wasn't a major concern, but we said, gee, you know, we
> just don't know how much further we can go below the 51 or 53 degrees
> or whatever it was. So we were concerned with the unknown. And we
> presented that to Marshall, and that rationale was rejected. They
> said that they didn't accept that rationale, and they would like us
> to consider some other thoughts that they had had.
> 
> ....Mr. Mulloy said he did not accept that,
> and Mr. Hardy said he was appalled that we would make such a
> recommendation. And that made me ponder of what I'd missed, and so we
> said, what did we miss, and Mr. Mulloy said, well, I would like you
> to consider these other thoughts that we have had down here. And he
> presented a very strong and forthright rationale of what they thought
> was going on in that joint and how they thought that the thing was
> happening, and they said, we'd like you to consider that when they
> had some thoughts that we had not considered.
> 
> .....So after the discussion with Mr. Mulloy,
> and he presented that, we said, well, let's ponder that a little bit,
> so we went offline to talk about what we-
> 
> Question:
> Who requested to go off-line?
> 
> Mr. Lund: I
> guess it was Joe Kilminster.
> 
> And so we went off line on the telecon . . .
> so we could have a roundtable discussion here.
> 
> Question:
> Who were the management people that were there?
> 
> Mr. Lund:
> Jerry Mason, Cal Wiggins, Joe, I, manager of engineering design, the
> manager of applied mechanics. On the chart.



Before the Commission on February 25, 1986,
Mr. Lund testified as follows regarding why he changed his position
on launching Challenger during the management caucus when he was
asked by Mr. Mason "To take off his engineering hat and put on his
management hat":15



> Chairman Rogers: How do you explain the fact that you seemed to change
> your mind when you changed your hat?
> 
> Mr. Lund: I
> guess we have got to go back a little further in the conversation
> than that. We have dealt with Marshall for a long time and have
> always been in the position of defending our position to make sure
> that we were ready to fly, and I guess I didn't realize until after
> that meeting and after several days that we had absolutely changed
> our position from what we had been before. But that evening I guess I
> had never had those kinds of things come from the people at Marshall.
> We had to prove to them that we weren't ready, and so we got
> ourselves in the thought process that we were trying to find some way
> to prove to them it wouldn't work, and we were unable to do that. We
> couldn't prove absolutely that that motor wouldn't work.
> 
> Chairman Rogers: In other words, you honestly believed that you had a
> duty to prove that it would not work?
> 
> Mr. Lund:
> Well, that is kind of the mode we got ourselves into that evening. It
> seems like we have always been in the opposite mode. I should have
> detected that, but I did not, but the roles kind of switched.
> .



Supplemental testimony of Mr. Mason obtained
in a Commission staff interview is as follows:16



> Question: Do you recall Mr. Hardy and Mr. Mulloy's comments
> after-I think after Mr. Kilminster had got done, or Mr. Lund got done
> presenting the charts? They had some comments. Do you recall-
> 
> Mr. Mason:
> Oh, yes, it was over and over. Hardy said that, "I'm appalled at your
> recommendation. ".
> 
> Question:
> Well, did Mr. Hardy's n «appalled" remark and Mr. Mulloy's
> "can't launch, we won't be able to launch until April"
> [95]
> remark, how did that affect your thinking and affect your
> decision?
> 
> Mr. Mason:
> My personal thinking, I just, you know, it didn't make that much
> difference .
> 
> And the comments that they made, in my view,
> probably had got more reaction from the engineer[s] at the lower
> level than they would from the manager[s], because we deal with
> people, and managers all the time....



Mr. McDonald indicated that during the period
of the internal Morton Thiokol caucus he continued to argue for delay
with Mulloy, challenging, among other things, the rationale that the
rocket motor was qualified down to 40 degrees Farhenheit. Present
were Reinartz, Jack Buchanan, the manager of Morton Thiokol Launch
Support Services at Kennedy, and Cecil Houston. McDonald's testimony
described that conversation:17



> Mr. McDonald: . . . while they were offline, reevaluating or
> reassessing this data . . . I got into a dialogue with the NASA
> people about such things as qualification and launch commit
> criteria.
> 
> The comment I made was it is my understanding
> that the motor was supposedly qualified to 40 to 90 degrees.
> 
> I've only been on the program less than three
> years, but I don't believe it was. I don't believe that all of those
> systems, elements, and subsystems were qualified to that
> temperature.
> 
> And Mr. Mulloy said well, 40 degrees is
> propellant mean bulk temperature, and we're well within that. That is
> a requirement. We're at 55 degrees for that-and that the other
> elements can be below that . . . that, as long as we don't fall out
> of the propellant mean bulk temperature. I told him I thought that
> was asinine because you could expose that large Solid Rocket Motor to
> extremely low temperatures-I don't care if it's 100 below zero for
> several hours-with that massive amount of propellant, which is a
> great insulator, and not change that propellant mean bulk temperature
> but only a few degrees, and I don't think the spec really meant
> that.
> 
> But that was my interpretation because I had
> been working quite a bit on the filament wound case Solid Rocket
> Motor. It was my impression that the qualification temperature was 40
> to 90, and I knew everything wasn't qualified to that temperature, in
> my opinion. But we were trying to qualify that case itself at 40 to
> 90 degrees for the filament wound case.
> 
> I then said I may be naive about what
> generates launch commit criteria, but it was my impression that
> launch commit criteria was based upon whatever the lowest
> temperature, or whatever loads, or whatever environment was imposed
> on any element or subsystem of the Shuttle. And if you are operating
> outside of those, no matter which one it was, then you had violated
> some launch commit criteria.
> 
> That was my impression of what that was. And I
> still didn't understand how NASA could accept a recommendation to fly
> below 40 degrees. I could see why they took issue with the 53, but I
> could never see why they would . . . of accept a recommendation below
> 40 degrees, even though I didn't agree that the motor was fully
> qualified to 40. I made the statement that if we're wrong and
> something goes wrong on this flight, I wouldn't want to have to be
> the person to stand up in front of board of inquiry and say that I
> went ahead and told them to go ahead and fly this thing outside what
> the motor was qualified to.
> 
> I made that very statement.



Mr. Mulloy's recollections of these discussion
are as follows:18



> Mr. Mulloy: Mr. Kilminster then requested an off-net caucus. It
> has been suggested, implied, or stated that we directed Thiokol to go
> reconsider these data. That is not true. Thiokol asked for a caucus
> so that they could consider the discussions that had ensued and the
> comments that Mr. Hardy and I and others had made.
> 
> That caucus, as has been stated, was going to
> start at that point, and Mr. McDonald interjected into the
> teleconference. At that point, he made the first comment that he had
> made during this entire teleconference.
> 
> Mr. McDonald testified for quite a while
> yesterday about his thoughts on this, but he did not say any of them
> until this point. At that point, he stated that he thought what
> George Hardy said was a very important [96] consideration, and
> that consideration was, and he asked Mr. Kilminster to be sure and
> consider the comment made by George Hardy during the course of the
> discussions, that the concerns expressed were for primary O-ring
> blow-by and that the secondary O-ring was in a position to seal
> during the time of blow-by and would do so before significant joint
> rotation had occurred.
> 
> They then went into their caucus, having asked
> for five minutes-
> 
> Mr. Hotz: .
> . . It figures quite prominently in the discussion that you were
> quoted as saying, do you expect us to wait till April to
> launch?
> 
> Mr. Mulloy:
> Yes, sir.
> 
> Dr. Walker:
> Is that an accurate statement or not?
> 
> Mr. Mulloy:
> It is certainly a statement that is out of context, and the way I
> read the quote, sir-and I have seen it many times, too many times-the
> quote I read was: My God, Thiokol, when do you want me to launch,
> next April?
> 
> Mr. McDonald testified to another quote that
> says: You guys are generating new Launch Commit Criteria.
> 
> Now, both of those I think kind of go
> together, and that is what I was saying. I don't know whether that
> occurred during the caucus or subsequent to. I just simply can't
> remember that.
> 
> Mr. Hotz:
> Well, never mind the timing.
> 
> Mr. Mulloy:
> Well, yes, sir. I'm going to answer your question now. I think those
> quotes derive from a single thought that may have been expressed by
> me using some of those words.
> 
> I have not yet encountered anyone other than
> those at KSC who heard those words, so I don't believe they were
> transmitted over the net. The total context I think in which those
> words may have been used is, there are currently no Launch Commit
> Criteria [LCC] for joint temperature. What you are proposing to do is
> to generate a new Launch Commit Criteria on the eve of launch, after
> we have successfully flown with the existing Launch Commit Criteria
> 24 previous times. With this LCC, i.e., do not launch with a
> temperature greater [sic] than 53 degrees, we may not be able to
> launch until next April. We need to consider this carefully before we
> jump to any conclusions.
> 
> It is all in the context, again, with
> challenging your interpretation of the data, what does it mean and is
> it logical, is it truly logical that we really have a system that has
> to be 53 degrees to fly?



At approximately 11 p.m. Eastern Standard
Time, the Thiokol/NASA teleconference resumed, the Thiokol management
stating that they had reassessed the problem, that the temperature
effects were a concern, but that the data were admittedly
inconclusive. Kilminster read the rationale recommending launch and
stated that that was Morton Thiokol's recommendation. Hardy requested
that it be sent in writing by telefax both to Kennedy and to
Marshall, and it was. The testimony of Mulloy and Hardy regarding the
remainder of the teleconference and their rationale for recommending
launch follows:19



> Mr. Mulloy: Okay, sir. At the completion of the caucus, of
> course, Mr. Kilminster came back on the loop and stated they had
> assessed all the data and considered the discussions that had ensued
> for the past couple of hours and the discussions that occurred during
> their caucus.
> 
> Chairman Rogers: Was it a couple of hours?
> 
> Mr. Mulloy:
> Yes, sir. We started at 8:45 and I believe it was probably 11:00
> o'clock before he came back on the loop. It was a long discussion.
> And I must emphasize that I had no knowledge of what interchange
> occurred during the caucus at Thiokol, because all sites were on
> mute. We were on mute at KSC. No communications occurred between
> myself and Mr. Hardy at Huntsville, nor did any communication occur
> between KSC and Thiokol during that caucus.
> 
> After Mr. Kilminster made that recommendation,
> Mr. Reinartz then asked if there were any further comments, and to my
> recollection there were none. There were no further comments
> made.
> 
> I then asked Mr. Kilminster to send me a copy
> of his flight readiness rationale and recommendation. The conference
> was then terminated at approximately 11:15.
> 
> I have no knowledge of, as has been testified,
> of Mr. McDonald being asked to sign that documentation. That would
> have....





---





---



> ....been unusual, because Mr.
> Kilminster signs all flight readiness documentation.
> 
> Now, after the teleconference was complete,
> Mr. McDonald informed Mr. Reinartz and me that if the Thiokol
> engineering concern for the effect of cold was not sufficient cause
> to recommend not launching, there were two other considerations,
> launch pad ice and recovery area weather.
> 
> I stated that launch pad ice had been
> considered by the Mission Management Team-
> 
> Chairman Rogers: Excuse me. Could you identify that discussion, where
> that took place?
> 
> Mr. Mulloy:
> That was after the teleconference was completed, after Mr. Kilminster
> made his recommendation, after Mr. Reinartz asked are there any other
> comments. There were no other comments on the telecon from
> anyone....
> 
> I stated that launch pad ice had been
> considered by the Mission Management Team before deciding to proceed
> and that a further periodic monitoring of that condition was planned.
> I further stated that I had been made aware of the recovery area
> weather previously and planned to place a call to Mr. Aldrich and
> advise him that the weather in the recovery area exceeded the Launch
> Commit Criteria.
> 
> So I stated earlier, when you asked what were
> the Launch Commit Criteria, one of them was that the recovery area
> weather has limitations on it. The report we had, that Mr. McDonald
> confirmed, was that we were outside of those limits.
> 
> Now, I must point out that that is not a hard
> Launch Commit Criteria. That is an advisory call, and the LCC so
> states that. It does require that we discuss the condition.
> 
> So at about 11:30 p.m., Mr. Cecil Houston
> established a teleconference with Mr. Aldrich and Mr. Sestile at KSC.
> I informed Mr. Aldrich that the weather in the [98] recovery area could
> preclude immediate recovery of the SRBs, since the ships were in a
> survival mode and they were moving back toward Cape Kennedy at about
> three knots, and the estimate provided to us by Mr. Sestile was that
> they would be probably 40 miles from the SRB impact area at the time
> of launch, at 9:38; and then, continuing at three knots, it was going
> to be some period of time before they could get back and locate the
> boosters.
> 
> The concern I had for that was not loss of the
> total booster, but loss of the main parachutes for the booster, which
> are separated at water impact, and loss of the frustum of the
> boosters, which has the drogue parachute on it, which comes down
> separately, because with the 50 knot winds we had out there and with
> the kind of sea states we had, by the time the recovery ships got
> back out there, there was little probability of being able to recover
> those.
> 
> I informed Mr. Aldrich of that, and he decided
> to proceed with the launch after that information. I did not discuss
> with Mr. Aldrich the conversations that we had just completed with
> Morton Thiokol.
> 
> Chairman Rogers: Could you explain why? Mr. Mulloy: Yes, sir. At that
> time, and I still consider today, that was a Level III issue, Level
> III being an SRB element or an external tank element or Space Shuttle
> main engine element or an Orbiter. There was no violation of Launch
> Commit Criteria. There was no waiver required in my judgment at that
> time and still today.
> 
> And we work many problems at the Orbiter and
> the SRB and the External Tank level that never get communicated to
> Mr. Aldrich or Mr. Moore. It was clearly a Level III issue that had
> been resolved.
> 
> . . . There were 27 full-scale seal tests with
> an O-ring groove damage tolerances, damage in the grooves and damage
> tolerance on O-rings. And then there were two cold gas tests.
> 
> And these data were presented on the night of
> the 27th. All of that was at ambient temperature. And then we did
> discuss what is a development qualification motor experience range,
> and that is shown on the chart. We had experience everywhere from 40
> to 85 degrees.
> 
> There then were data presented on two cold gas
> tests at 30 degrees, where the O-ring was pressurized at the motor
> pressurization rate at 30 degrees, which would indicate that an
> O-ring would operate before joint rotation at 30 degrees.
> 
> Dr. Ride:
> Was that actually in a joint?
> 
> Mr. Mulloy:
> No, it is not. It is a full-scale O-ring, full-scale groove, in a
> scaled test device, where the pressurize rate on that O-ring is zero
> to 900 psi [pounds per square inch] in 600 milliseconds at a
> temperature of 30 degrees.
> 
> Dr. Walker:
> You would say, then, the O-ring was qualified to a temperature of 30
> degrees? Would that be an accurate statement?
> 
> Mr. Mulloy:
> The day that we were looking at it, on the 27th, these two tests that
> we did indicated that it would perform at 30 degrees under the motor
> pressurization rate before the joint rotated.
> 
> Dr. Walker:
> What about, let's consider the putty and the O-ring, because that is
> really the system that responds to the pressure surge. What
> temperature was the putty/O-ring system qualified to?
> 
> Mr. Mulloy:
> The lowest that I'm aware of-and we're still flushing this out,
> because this is kind of what we talked about on the 27th, but the
> lowest that I'm aware of is the 40-degree test on one of the
> development motors.
> 
> Dr. Walker:
> And, of course, during those tests the putty was modified before the
> test. The putty was not just laid up and then the seal made. The
> putty was then smoothed out or some attempt was made to remove the
> volcanoes, I think.
> 
> Mr. Mulloy:
> Because the horizontal assembly caused that.
> 
> Now, there's one other significant point on
> this chart that we did discuss, that we didn't have the quantities on
> on the 27th, and I mentioned this earlier. We have 150 case segment
> proof tests, with a large number of joints with a simulation of a
> cold O-ring. That is the 90 durometer with a .275, and that was at
> about 35 degrees.
> 
> [99] So those are the
> certification data that we kind of discussed, all of which we didn't
> discuss. The two cold gas tests we did, the segment proof tests we
> did, the development and qualification motor test we did, as a basis
> for understanding what we could expect to happen at colder
> temperatures on the joints.



Mr. Hardy testified as
follows:20



> Mr. Hardy: At the teleconference on the evening of January 27,
> 1986, Thiokol engineering personnel in Utah reviewed charts that had
> been datafaxed to Huntsville and KSC participants just prior to the
> beginning of the conference. Now, I am not going to repeat a lot of
> what you have already heard, but I will give you some of my views on
> the whole matter.
> 
> The presentations were professional in nature.
> There were numerous questions and answers. There was a discussion of
> various data and points raised by individuals at Thiokol or at
> Marshall or at Kennedy. I think it was a rather full discussion.
> There were some 14 charts presented, and as has been mentioned
> earlier, we spent about two, two and a half hours reviewing this. To
> my knowledge, anyone who desired to make a point, ask a question or
> express a view was in no way restrained from doing so.
> 
> As others have mentioned, I have heard this
> particular teleconference characterized as a heated discussion. I
> acknowledge that there were penetrating questions that were asked, I
> think, from both, from all people involved. There were various points
> of view and an interpretation of the data that was exchanged. The
> discussion was not, in my view, uncharacteristic of discussions on
> many flight readiness issues on many previous occasions. Thiokol
> engineering concluded their presentation with recommendation that the
> launch time be determined consistent with flight experience to date,
> and that is the launch with the O-ring temperatures at or greater
> than 53 degrees Fahrenheit.
> 
> Mr. Kilminster at Thiokol stated . . . to the
> best of my recollection, that with that engineering assessment, he
> recommended we not launch on Tuesday morning as scheduled. After some
> short discussion, Mr.
> 
> Mulloy at KSC summarized his assessment of the
> data and his rationale with that data, and I think he has testified
> to that.
> 
> Mr. Reinartz, who was at KSC, asked me for
> comment, and I stated I was somewhat appalled, and that was referring
> specifically to some of the data or the interpretation of some of the
> data that Thiokol had presented with respect to its influence on the
> joint seal performance relative to the issue under discussion, which
> specifically was the possibility that the primary seal may take
> longer to actuate and therefore to blow by the primary seal. The
> blow-by of the primary seal may be longer, and I am going to
> elaborate on that a little further in this statement.
> 
> Then I went on to say that I supported the
> assessment of data presented essentially as summarized by Mr. Mulloy,
> but I would not recommend launch over Thiokol's objections.
> 
> Somewhere about this time, Mr. Kilminster at
> Utah stated that he wanted to go off the loop to caucus for about
> five minutes. I believe at this point Mr. McDonald, the senior
> Thiokol representative at KSC for this launch suggested to Mr.
> Kilminster that he consider a point that I think I had made earlier,
> that the secondary O-ring is in the proper position to seal if
> blow-by of the primary O-ring occurred.
> 
> I clearly interpreted this as a somewhat
> positive statement of supporting rationale for launch.... The status
> of the caucus by Thiokol lasted some 30, 35 minutes. At Huntsville
> during this Thiokol caucus, we continued to discuss the data
> presented. We were off the loop, we were on mute. We were around a
> table in small groups. It was not an organized type discussion. But I
> did take that opportunity to discuss my assessment and understanding
> of the data with several of my key advisors, and none of us had any
> disagreement or differences in our interpretation of what we believed
> the data was telling us with regard to the primary issue at
> hand.
> 
> When Thiokol came back on line, Mr. Kilminster
> reviewed rationale that supported proceeding with the launch and so
> recommended.
> 
> [100] Mr. Reinartz asked
> if anyone in the loop had a different position or disagreed or
> something to that effect, with the Thiokol recommendation as
> presented by Mr. Kilminster. There were no dissenting
> responses.
> 
> The telecon was terminated shortly after, and
> I have no knowledge of any subsequent events or discussions between
> personnel at KSC or at Thiokol on this matter.



At about 5:00 a. m . on January 28, a
discussion took place among Messrs. Mulloy, Lucas, and Reinartz in
which Mulloy reported to Lucas only that there had been a discussion
with Thiokol over their concerns about temperature effects on the
O-rings, and that it had been resolved in favor of launch. The
following testimony of Mr. Mulloy and Dr. Lucas recount that
discussion:21



> General Kutyna: . . . Larry, let me follow through on that, and I am
> kind of aware of the launch decision process, and you said you made
> the decision at your level on this thing.
> 
> If this were an airplane, an airliner, and I
> just had a two-hour argument with Boeing on whether the wing was
> going to fall off or not, I think I would tell the pilot, at least
> mention it.
> 
> Why didn't we escalate a decision of this
> importance ?
> 
> Mr. Mulloy:
> I did, sir.
> 
> General Kutyna: You did? Mr. Mulloy: Yes, sir.
> 
> General Kutyna: Tell me what levels above you.
> 
> Mr. Mulloy:
> As I stated earlier, Mr. Reinartz, who is my manager, was at the
> meeting, and on the morning, about 5:00 o'clock in the operations
> support room where we all were I informed Dr. Lucas of the content of
> the discussion.
> 
> General Kutyna: But this is not in the launch decision chain.
> 
> Mr. Mulloy:
> No, sir. Mr. Reinartz is in the launch decision chain, though.
> 
> General Kutyna: And is he the highest level in that chain?
> 
> Mr. Mulloy:
> No. Normally it would go from me to Mr. Reinartz to Mr. Aldrich to
> Mr. Moore.



Dr. Lucas' testimony is as
follows:22



> Chairman Rogers: Would you please tell the Commission when you first
> heard about the problem of the O-rings and the seals insofar as it
> involves launch 51-L? And I don't want you to go way back, but go
> back to when you first heard. I guess it was on January 27th, was
> it?
> 
> Dr. Lucas:
> Yes, sir. It was on the early evening of the 27th, I think about 7:00
> p.m., when I was in my motel room along with Mr. Kingsbury. And about
> that time, Mr. Reinartz and Mr. Mulloy came to my room and told me
> that they had heard that some members of Thiokol had raised a concern
> about the performance of the Solid Rocket Boosters in the low
> temperature that was anticipated for the next day, specifically on
> the seals, and that they were going out to the Kennedy Space Center
> to engage in a telecon with the appropriate engineers back at
> Marshall Space Flight Center in Huntsville and with corresponding
> people back at the Wasatch division of Thiokol in Utah.
> 
> And we discussed it a few moments and I said,
> fine, keep me informed, let me know what happens.
> 
> Chairman Rogers: And when was the next time you heard something about
> that?
> 
> Dr. Lucas:
> The next time was about 5:00 a.m. on the following morning, when I
> went to the Kennedy Space Center and went to the launch control
> center. I immediately saw Mr. Reinartz and Mr. Mulloy and asked them
> how the matter of the previous evening was dispositioned.
> 
> Chairman Rogers: You had heard nothing at all in between?
> 
> Dr. Lucas:
> No, sir.
> 
> Chairman Rogers: So from 8:00 o'clock that evening until 5:00 o'clock
> in the morning, you had not heard a thing?
> 
> Dr. Lucas:
> It was about 7:00, I believe, sir. But for that period of time, I
> heard nothing in the interim. . .
> 
> Chairman Rogers: . . . And you heard Mr. Reinartz say he didn't think
> he had to notify you, or did he notify you?
> 
> Dr. Lucas:
> He told me, as I testified, when I went into the control room, that
> an issue had been resolved, that there were some people
> [101] at
> Thiokol who had a concern about the weather, that that had been
> discussed very thoroughly by the Thiokol people and by the Marshall
> Space Flight Center people, and it had been concluded agreeably that
> there was no problem, that he had a recommendation by Thiokol to
> launch and our most knowledgeable people and engineering talent
> agreed with that. So from my perspective, I didn't have-I didn't see
> that as an issue.
> 
> Chairman Rogers: And if you had known that Thiokol engineers almost to
> a man opposed the flight, would that have changed your view?
> 
> Dr. Lucas:
> I'm certain that it would.
> 
> Chairman Rogers: So your testimony is the same as Mr. Hardy's. Had he
> known, he would not have recommended the flight be launched on that
> day.
> 
> Dr. Lucas: I
> didn't make a recommendation one way or the other. But had I known
> that, I would have then interposed an objection, yes.
> 
> Chairman Rogers: I gather you didn't tell Mr. Aldrich or Mr. Moore
> what Mr. Reinartz had told you?
> 
> Dr. Lucas:
> No, sir. That is not the reporting channel. Mr. Reinartz reports
> directly to Mr. Aldrich. In a sense, Mr. Reinartz informs me as the
> institutional manager of the progress that he is making in
> implementing his program, but that I have never on any occasion
> reported to Mr. Aldrich.
> 
> Chairman Rogers: And you had subsequent conversations with Mr. Moore
> and Mr. Aldrich prior to the flight and you never mentioned what Mr.
> Reinartz had told you? Dr. Lucas: I did not mention what Mr. Reinartz
> told me, because Mr. Reinartz had indicated to me there was not an
> issue, that we had a unanimous position between Thiokol and the
> Marshall Space Flight Center, and there was no issue in his judgment,
> nor in mine as he explained it to me. Chairman Rogers: But had you
> known, your attitude would have been totally different?
> 
> Dr. Lucas:
> Had I had the advantage at that time of the testimony that I have
> heard here this week, I would have had a different attitude,
> certainly.
> 
> Chairman Rogers: In view of the fact that you were running tests to
> improve the joint, didn't the fact that the weather was so bad and
> Reinartz had told you about the questions that had been raised by
> Thiokol, at least, didn't that cause you serious concern? Dr. Lucas:
> I would have been concerned if Thiokol had come in and said, we don't
> think you should launch because we've got bad weather.
> 
> Chairman Rogers: Well, that's what they did, of course, first. That is
> exactly what they did. You didn't know that?
> 
> Dr. Lucas: I
> knew only that Thiokol had raised a concern.
> 
> Chairman Rogers: Did you know they came and recommended against the
> launch, is the question?
> 
> Dr. Lucas: I
> knew that I was told on the morning of the launch that the initial
> position of some members of Thiokol-and I don't know who it was-had
> recommended that one not launch with the temperature less than 53
> degrees Fahrenheit.
> 
> Chairman Rogers: And that didn't cause you enough concern so you
> passed that information on to either Mr. Moore or Mr. Aldrich?
> 
> Dr. Lucas:
> No, sir, because I was shown a document signed by Mr. Kilminster that
> indicated that that would not be significant, that the temperature
> would not be-that it would be that much lower, as I recall it.



It is clear that crucial information about the
O-ring damage in prior flights and about the Thiokol engineers'
argument with the NASA telecon participants never reached Jesse Moore
or Arnold Aldrich, the Levels I and II program officials, or J.A.
(Gene) Thomas, the Launch Director for 51-L. The testimony of Aldrich
describes this failure of the communication system very
aptly:23



> Dr. Feynman: . . . have you collected your thoughts yet on what
> you think is the cause-I wouldn't call it of the accident but the
> lack of communication which we have seen and which everybody is
> worried about from one level to another? . . .
> 
> Mr. Aldrich:
> Well, there were two specific breakdowns at least, in my impression,
> [102]
> about that situation. One is the situation that occurred the night
> before the launch and leading up to the launch where there was a
> significant review that has been characterized in a number of ways
> before the Commission and the Commission's Subpanels and the fact
> that that was not passed forward.
> 
> And I can only conclude what has been
> reported, and that is that the people responsible for that work in
> the Solid Rocket Booster project at Marshall believed that the
> concern was not of a significance that would be required to be
> brought forward because clearly the program requirements specify that
> critical problems should be brought forward to Level II and not only
> to Level II but through myself to Level I.
> 
> The second breakdown in communications,
> however, and one that I personally am concerned about is the
> situation of the variety of reviews that were conducted last summer
> between the NASA Headquarters Organization and the Marshall
> Organization on the same technical area and the fact that that was
> not brought through my office in either direction-that is, it was not
> worked through-by the NASA Headquarters Organization nor when the
> Marshall Organization brought these concerns to be reported were we
> involved.
> 
> And I believe that is a critical breakdown in
> process and I think it is also against the documented reporting
> channels that the program is supposed to operate to.
> 
> Now, it in fact did occur in that matter. In
> fact, there is a third area of concern to me in the way the program
> has operated. There is yet one other way that could have come to me,
> given a different program structure. I'm sure you've had it reported
> to you as it has been reported to me that in August or I think or at
> least at some time late in the summer or early fall the Marshall SRB
> project went forward to procure some additional Solid Rocket Motor
> casings to be machined and new configurations for testing of the
> joints.
> 
> Now it turns out that the budget for that kind
> of work does not come through my Level II office. It is worked
> directly between the Marshall Center in NASA Headquarters and there
> again had I been responsible for....





---





---



> [103] ....the budget for
> that sort of work, it would have to come through me, and it would
> have been clear that something was going on here that I ought to know
> about.
> 
> And so there are three areas of' breakdown,
> and I haven't exactly answered your question. But I have explained it
> in the way that I best know it and-well, I can say a fourth
> thing.
> 
> There was some discussion earlier about the
> amount of material that was or was not reported on O-ring erosion in
> the FRRs [Flight Readiness Reviews] and I researched the FRR back
> reports and also the flight anomaly reports that were forwarded to my
> center-to my office-by the SRB [Solid Rocket Booster] project and as
> was in-dicated, there is a treatment of the Solid Rocket Motor O-ring
> erosion, I believe, for the STS 41-C FRR, which quantifies it and
> indicates some limited amount of concern.
> 
> The next time that is mentioned, I believe it
> is the STS 51-E, FRR in January 1985 or early in February, and that
> indicates, again, a reference to it but refers back to the 41-C as
> the only technical data.
> 
> And then from there forward the comment on
> O-ring erosion only is that there was another instance and it is not
> of concern.
> 
> Clearly the amount of reporting in the FRR is
> of concern to me, but in parallel with that, each of the flight
> anomalies in the STS program are required to be logged and reviewed
> by each of the projects and then submitted through the Level II
> system for formal close-out.
> 
> And in looking back and reviewing the anomaly
> close-outs that were submitted to Level II from the SRB project, you
> find that O-ring erosion was not considered to be an anomaly and,
> therefore, it was not logged and, therefore, there are not anomaly
> reports that progress from one flight to the other.
> 
> Yet, that is another way that that information
> could have flagged the system, and the system is set up to use that
> technique for flagging.
> 
> But if the erosion is classified as not an
> anomaly, it then is in some other category and the system did not
> force it in that direction. None of those are very focused answers,
> but they were all factors.



The Commission Chairman, Mr. Rogers, asked
four key officials about their knowledge of the Thiokol objections to
launch:24



> Chairman Rogers: . . . By way of a question, could I ask, did any of
> your gentlemen prior to launch know about the objections of Thiokol
> to the launch?
> 
> Mr. Smith[Kennedy Space Center Director]: I did not.
> 
> Mr. Thomas[Launch Director]: No, sir. Mr. Aldrich [Shuttle Program Director]: I
> did not.
> 
> Mr. Moore[Associate Administrator for Space Flight]: I did not.



Additionally, in further testimony J.A. (Gene)
Thomas commented on the launch.25



> Mr. Hotz: . . . Mr. Thomas, you are familiar with the testimony
> that this Commission has taken in the last several days on the
> relationship of temperature to the seals in the Solid Rocket
> Booster?
> 
> Mr. Thomas:
> Yes, sir, I have been here all week.
> 
> Mr. Hotz: Is
> this the type of information that you feel that you should have as
> Launch Director to make a launch decision?
> 
> Mr. Thomas:
> If you refer to the fact that the temperature according to the Launch
> Commit Criteria should have been 53 degrees, as has been testified,
> rather than 31, yes, I expect that to be in the LCC. That is a
> controlling document that we use in most cases to make a decision for
> launch.
> 
> Mr. Hotz:
> But you are not really very happy about not having had this
> information before the launch?
> 
> Mr. Thomas:
> No, sir. I can assure you that if we had had that information, we
> wouldn't have launched if it hadn't been 53 degrees.



[104]Findings



l. The Commission concluded that there was a
serious flaw in the decision making process leading up to the launch
of flight 51-L. A well structured and managed system emphasizing
safety would have flagged the rising doubts about the Solid Rocket
Booster joint seal. Had these matters been clearly stated and
emphasized in the flight readiness process in terms reflecting the
views of most of the Thiokol engineers and at least some of the
Marshall engineers, it seems likely that the launch of 51-L might not
have occurred when it did.

2. The waiving of launch constraints appears
to have been at the expense of flight safety. There was no system
which made it imperative that launch constraints and waivers of
launch constraints be considered by all levels of management.

3. The Commission is troubled by what appears
to be a propensity of management at Marshall to contain potentially
serious problems and to attempt to resolve them internally rather
than communicate them forward. This tendency is altogether at odds
with the need for Marshall to function as part of a system working
toward successful flight missions, interfacing and communicating with
the other parts of the system that work to the same end.

4. The Commission concluded that the Thiokol
Management reversed its position and recommended the launch of 51-L,
at the urging of Marshall and contrary to the views of its engineers
in order to accommodate a major customer.



Chronology of Events Related to
         Temperature Concerns Prior to Launch of Challenger (STS
         51-L).TimeKey ParticipantsEvent.12:36 PM (EST)
            
            January 27, 1986NASA Project Managers and
         Contractor Support Personnel (including Morton
         Thiokol).Launch Scrub. Decision is made to scrub due to high
            crosswinds at launch site..Approximately
            
            l :00 PM ( EST)Same as above.Post-Scrub
            Discussion. All
            appropriate personnel are polled as to feasibility to
            launch again with 24-hour cycle and it results in no SRB
            constraints for launch at 9:38 AM, 28 January
            1986.Request is made for all
            participants to report any constraints..Approximately
            
            1:00 PM (EST)Kennedy Space Center
         
         (1) Boyd C. Brinton, Manager,
            Space Booster Project, MTI;
            
            (2) Lawrence O. Wear, Manager,
            SRM Project Office, Marshall.Conversation. Wear asks Brinton if Thiokol had any
            concerns about predicted low temperatures and about what
            Thiokol had said about cold temperature effects following
            January 1985 flight 51-C.Morton Thiokol, Utah
         
         (1) Arnold R. Thompson,
            Supervisor, Rocket Motor Cases;
            
            (2) Robert Ebeling, Manager,
            Ignition System and Final Assembly SRM Project.Brinton telephones Thompson and
            other MTI personnel to ask them to determine if there
            were concerns based on predicted weather conditions.
            Ebeling and other engineers are notified and asked for
            evaluation..[105]
            Approximately
            
            2:00 PM (EST)NASA Levels I and II Management
         With Appropriate Program Managers and Contract
         Personnel
         
         (1) Jesse W. Moore, Associate
            Administrator, Space Flight, NASA HQ and Director,
            JSC;
            
            (2) Arnold D. Aldrich, Manager,
            Space Transportation Systems Program, JSC;
            
            (3) Lawrence B. Mulloy, Manager,
            SRB Project, Marshall Space Flight Center (MSFC)
            
            (4) Dr. William Lucas, Director,
            MSFC.Mission Management Team
            Meeting. Discussion is
            centered around the temperature at the launch facility
            and weather conditions predicted for launch at 9:38 AM on
            28 January 1986..Approximately
            
            2:30 PM (EST)At Thiokol, Utah
         
         (1) R. Boisjoly, Seal Task Force,
            Morton Thiokol, Utah;
            
            (2) Robert Ebeling, Manager,
            Ignition System and Final Assembly, SRM Project.Boisjoly learns of cold
            temperatures at Cape at meeting convened by
            Ebeling.Approximately
            
            4:00 PM (EST)At Kennedy Space Center
         
         (1) Allan J. McDonald, Director,
            SRM Project, Morton Thiokol;
            
            (2) Carver Kennedy, Director of'
            Vehicle Assembly Building Operations, and Vice President
            of Space Operations at KSC, for Morton Thiokol. At
            Thiokol, Utah Robert Ebeling, Department Manager,
            Ignition System and Final Assembly, SRM Project.Telephone
            Conversation. McDonald
            receives call at Carver Kennedy's residence from Ebeling
            expressing concern about performance of SRB field joints
            at low temperatures.McDonald indicates he will call
            back latest temperature predictions up to launch
            time.Carver Kennedy calls Launch
            Operations Center and received latest temperature
            information.McDonald transmits data to Utah
            and indicates will set up telecon and asks engineering to
            prepare..Approximately
            
            5:15 PM (EST)At Kennedy Space Center
         
         (1) Allan J. McDonald, Director,
            SRM Project, Morton Thiokol, Inc.;
            
            (2) Cecil Houston, MSFC Resident
            Manager, at KSC.Telephone
            Conversation. McDonald
            calls Cecil Houston informing him that Morton Thiokol
            engineering had concerns regarding O-ring
            temperatures.Cecil Houston indicates he will
            set up teleconference with Marshall Space Flight Center
            and Morton Thiokol..[106]
            Approximately
            
            5:25 PM (EST)At Kennedy Space Center
         
         Cecil Houston, MSFC Resident Manager,
         at KSC.
         
         At Marshall Space Flight
         Center
         
         Judson A. Lovingood, Deputy Manager,
         Shuttle Projects Office, MSFC.Telephone
            Conversation. Cecil
            Houston calls Lovingood, informing him of the concerns of
            temperature on the O-rings and asks him to establish a
            telecon with:
            
            (1) Stanley R. Reinartz,
               Manager, Shuttle Projects Office, MSFC (at Kennedy);
               
               (2) Lawrence B. Mulloy,
               Manager, SRB Project, MSFC (at Kennedy);
               
               (3) George Hardy, Deputy
               Director, Science and Engineering (at Marshall);
               
               (4) Thiokol Wasatch Division
               personnel..Approximately
            
            5:30 PM (EST)At Kennedy Space Center
         
         Stanley R. Reinartz, Manager, Shuttle
         Projects Office, MSFC
         
         At Marshall Space Flight Center
         
         Judson A. Lovingood, Deputy Manager,
         Shuttle Projects Office, MSFC.Telephone
            Conversation. Lovingood
            calls Reinartz to inform him of planned 5:45 PM (EST)
            teleconference.Lovingood proposes that Kingsbury
            (Director of Science and Engineering MSFC), participate
            in teleconference..Approximately
            
            5:45 PM (EST)At Kennedy Space
         Center
         
         Stanley R. Reinartz, Manager, Shuttle
         Projects Office (MSFC).
         
         At Marshall Space Flight Center
         
         Judson A. Lovingood, Deputy Manager,
         Shuttle Projects Office, MSFC.
         
         Plus other personnel at Kennedy,
         Marshall, and Thiokol, Utah.First
            Teleconference. Concerns
            regarding temperature effects on the O-rings are
            discussed.MTI is of the opinion launch
            should be delayed until Noon or afternoon.It is decided that another
            telecon at 8:15 PM will be set up to transmit the data to
            all of the parties and to have more personnel
            involved.Lovingood recommends to Reinartz
            to include Lucas, Director, MSFC and Kingsbury in 8:45 PM
            conference and to plan to go to Level II if MTI
            recommends not launching..Approximately
            
            6:30 PM (EST)At Marshall Space Flight Center
         
         Judson A. Lovingood, Deputy Manager,
         Shuttle Projects Office MSFC.
         
         At Kennedy Space Center
         
         Stanley R. Reinartz, Manager, Shuttle
         Projects Office, MSFC.Telephone
            Conversation. Lovingood
            calls Reinartz and tells him that if Thiokol persists,
            they should not launch.Lovingood also suggests advising
            Aldrich, Manager, National Transportation System (Level
            II), of teleconference to prepare him for Level I meeting
            to inform of possible recommendation to delay..[107]
            Approximately
            
            7:00 PM (EST)At Kennedy Space Center
         
         (1) Lawrence B. Mulloy, Manager,
            SRB Project, MSFC.
            
            (2) Stanley R. Reinartz, Manager,
            Shuttle Projects Office, MSFC;
            
            (3) Dr. William Lucas, Director,
            MSFC;
            
            (4) Jim Kingsbury, Director of
            Science and Engineering, MSFC.Conversation. Reinartz and Mulloy visit Lucas and
            Kingsbury in their motel rooms to inform them of Thiokol
            concern and planned teleconference..Approximately
            
            8:45 PM (EST)At Morton Thiokol, Utah
         
         (1) Jerald Mason, Senior Vice
            President, Wasatch Operations;
            
            (2) Calvin Wiggins, Vice
            President and General Manager, Space Division,
            Wasatch;
            
            (3) Joe C. Kilminster, Vice
            President, Space Booster Programs, Wasatch;
            
            (4) Robert K. Lund, Vice
            President, Engineering;
            
            (5) Roger Boisjoly, Member Seal
            Task Force;
            
            (6) Arnold R. Thompson,
            Supervisor, Rocket Motor Cases.At Kennedy Space Center
         
         (1) Stanley R. Reinartz, Manager,
            Shuttle Projects Office, MSFC;
            
            (2) Lawrence B. Mulloy, Manager,
            SRB Project, MSFC;
            
            (3) Allan J. McDonald, Director,
            SRM Project, MTI.At Marshall Space Flight Center
         
         (1) George B. Hardy, Deputy
            Director, Science and Engineering;
            
            (2) Judson A. Lovingood, Deputy
            Manager, Shuttle Project Office;
            
            (3) Ben Powers, Engineering
            Structures and Propulsion. Plus other personnel (see
            table page 111).Second
            Teleconference. Charts
            present a history of the O-ring erosion and blow-by for
            the primary seal in the field joints, including results
            of subscale tests, previous flights and static tests of
            Solid Rocket Motors.The data shows that the timing
            function of the O-rings will be slower due to lower
            temperatures and that the worst blow-by occurred on SRM
            15 (STS 51-C) in January 1985 with O-ring temperatures of
            53 degrees Fahrenheit.Recommendation by Thiokol (Lund)
            is not to fly STS 51-L (SAM-25) until the temperature of
            the O-ring reached 53 degrees Fahrenheit, which was the
            lowest temperature of any previous flight.Mulloy asks for recommendation
            from Kilminster.Kilminster states that based upon
            the engineering recommendation, he can not recommend
            launch.Hardy is reported by both
            McDonald and Boisjoly to have said he is "appalled" by
            Thiokol's recommendation.Reinartz comments that he is
            under the impression that SRM is qualified from 40
            degrees Fahrenheit to 90 degrees Fahrenheit. ~ NASA
            personnel challenge conclusions and
            recommendations.Kilminster asks for five minutes
            off

[108]TimeKey ParticipantsEvent.Approximately
            
            10:30 PM (EST)Thiokol Personnel
         
         (1) Jerald Mason, Senior Vice
            President, Wasatch Operations;
            
            (2) Joe C. Kilminster, Vice
            President, Space Booster Program;
            
            (3) Calvin Wiggins, Vice
            President and General Manager, Space Division;
            
            (4) Robert K. Lund, Vice
            President, Engineering;
            
            (5) Arnold R. Thompson,
            Supervisor, Rocket Motor Cases;
            
            (6) Roger Boisjoly, Member, Seal
            Task Force;
            
            (7) Brian Russell, Special
            Projects SRM Program Office;
            
            (8) Robert Ebeling, Manager,
            Ignition System and Final Assembly, SRM Project.
            
            Plus other personnelThiokol Caucus. Caucus continues for about 30 minutes at
            Thiokol, Wasatch, Utah.Major issues are (1) temperature
            effects on O-ring, and (2) erosion of the O-ring.Thompson and Boisjoly voice
            objections to launch and indication is that Lund also is
            reluctant to launch.A final management review is
            conducted with only Mason, Lund, Kilminster, and
            Wiggins.Lund is asked to put on
            management hat by Mason.Final agreement is: (1) there is
            a substantial margin to erode the primary O-ring by a
            factor of three times the previous worst case, and (2)
            even if the primary O-ring does not seal, the secondary
            is in position and will..Approximately
            
            10:30 PM to 11:00 PM (EST)At Kennedy Space Center
         
         (1) Allan J. McDonald, Manager,
            Space Booster Project, Morton Thiokol, Inc. (MTI);
            
            (2) Lawrence B. Mulloy, Manager,
            SRB Projects, MSFC;
            
            (3) Stanley R. Reinartz, Manager,
            Shuttle Projects, MSFC;
            
            (4) Jack Buchanan, Manager, KSC
            Operations, for MTI;
            
            (5) Cecil Houston, MSFC Resident
            manager, at KSC.Conversation at
            Kennedy. McDonald
            continues to argue for delay.McDonald challenges Reinartz's
            rationale that SRM is qualified at 40 degrees F. to 90
            degrees F., and Mulloy's explanation that Propellant Mean
            Bulk Temperatures are within specifications..Approximately
            
            11:00 PM (EST)Same participants at 8:45 PM
            Teleconference.Second Teleconference
            (Cont'd). Thiokol
            indicates it had reassessed; temperature effects are
            concern, but data is inconclusive.Kilminster reads the rationale
            for recommending launch.Thiokol recommends launch.Hardy requests that Thiokol put:
            writing their recommendation and send it by fax to both
            Kennedy and Marshall..[109]
            Approximately
            
            11:15 to 11:30 PM (EST)At Kennedy Space Center
         
         (1) Allan J . McDonald, Manager,
            Space Booster Project, MTI;
            
            (2) Lawrence Mulloy, Manager, SRB
            Projects Office, MSFC;
            
            (3) Stanley R. Reinartz, Manager,
            Shuttle Projects Office, MSFC;
            
            (4) Jack Buchanan, Manager, KSC
            Operations, for MTI;
            
            (5) Cecil Houston, Manager, MSFC
            Resident Office at KSC.Conversation at
            Kennedy. McDonald argues
            again for delay asking how NASA could rationalize
            launching below qualification temperature.McDonald indicates if anything
            happened, he would not want to have to explain to Board
            of Inquiry.McDonald indicates he would
            cancel launch since (1) O-ring problem at low
            temperatures; (2) booster recovery ships heading into
            wind toward shore due to high seas, and (3) icing
            conditions on launch pad.McDonald is told it is not his
            concern and that his above concerns will be passed on in
            advisory capacity..Approximately
            
            11:45 PM (EST)Telefax. Kilminster faxes Thiokol's recommendation
            to launch at 9:45 M EST, 27 January 1986 ( 11 :45
            ESTFax is signed by
            Kilminster.McDonald retrieves fax at
            KSC..Approximately
            
            11:30 PM to 12:00 AM (EST)At Kennedy Space Center
         
         (1) Lawrence B. Mulloy, Manager,
            SRB Projects Office, MSFC;
            
            (2) Stanley R. Reinartz, Manager,
            Shuttle Projects, MSFC;
            
            (3) Arnold D. Aldrich, Manager,
            National Space Transportation System Program Office,
            JSC.Teleconference. Discussion centers around the recovery
            ships' activities and brief discussion of the ice issue
            on the launch complex area.Reinartz and Mulloy place call to
            Aldrich.McDonald delivers fax to Jack
            Buchanan's office at Kennedy Space Center and overhears
            part of conversation.Aldrich is apparently not
            informed of the O-ring concerns..Approximately
            
            12:01 AM (EST)
            
            January 28Kennedy Space Center meeting
            breaks up..Approximately
            
            1:30 to 3:00 AM (EST)At Kennedy Space Center
         
         (1) Charles Stevenson, Supervisor
            of Ice Crew; KSC
            
            (2) B.K. Davis, Ice Team Member,
            MSFCIce Crew Inspection of Launch
            Pad B.Ice crew finds large quantity of
            ice on Fixed Service Structure, mobile launch platform,
            and pad apron; and reports conditions..Approximately
            
            5:00 AM (EST)At Kennedy Space Center
         
         (1) Lawrence B. Mulloy, Manager,
            SRB Project, MSFC;
            
            (2) Dr. William Lucas, Director,
            (MSFC);
            
            (3) Jim Kingsbury, Director of
            Science and Engineering, MSFC.Conversation. Mulloy tells Lucas of Thiokol's concerns
            over temperature effects on O-rings and final
            resolution.Lucas is shown copy of Thiokol
            telefax..[110]
            Approximately
            
            7:00-9:00 AM (EST)At Kennedy Space Center
         
         (1) Charles Stevenson, Supervisor
            of Ice Crew, KSC;
            
            (2) B. K. Davis, Ice Team Member
            MSFC .Ice Crew Inspection of Launch
            Pad B. Ice crew inspects
            Launch Pad B and Challenger for ice formation.Davis measures temperatures on
            SRBs, External Tank, Orbiter, and launch pad with
            infrared pyrometer.Left-hand SRB appears to be about
            25 degrees F. and right-hand SRB appears to be about 8
            degrees F. near the aft region.Ice crew is not concerned since
            there is no Launch Commit Criteria on surface
            temperatures and does not report.Crew reports patches of sheet ice
            on lower segment and skirt of left Solid Rocket
            Booster..Approximately
            
            8:00 AM (EST)At Marshall Space Flight Center
         
         (1) Judson A. Lovingood, Deputy
            Manager, Shuttle Projects Office, MSFC;
            
            (2) Jack Lee, Deputy Director
            MSFC.Conversation. Lovingood informs Lee of previous night's
            discussions.He indicates that Thiokol had at
            first recommended not launching, and then after Wasatch
            conference recommended launching.He also informs Lee that Thiokol
            is providing in writing their recommendation for
            launch..Approximately
            
            9:00 AM (EST)NASA Levels I and Level II
         Management With Appropriate Project Managers and Contract
         Personnel.Mission Management Team
            Meeting. Ice conditions at
            launch complex are discussed. There is no apparent
            discussion of temperature effects on O-ring seal..Approximately
            
            10:30 AM (EST)At Kennedy Space Center
         
         (1) Charles Stevenson, Supervisor
            of Ice Crew;
            
            (2) B.K. Davis, Ice Team
            MemberIce Crew Inspection of Launch
            Pad B. Ice crew inspects
            Launch Pad B for third time.Crew removes ice from water
            troughs, returns to Launch Control Center at T-20
            minutes, reports conditions to Mission Management Team
            including fact that ice is still on left Solid Rocket
            Booster..11:38 AM (EST)Launch. Challenger (STS 51-L) is launched.



[111]Final Teleconference Participants

NASA Marshall Space Flight
         Center.Morton Thiokol Wasatch
         Division..1. George B. Hardy, Deputy Director,
         Science and Engineering, MSFC1. Jerald Mason, Senior Vice
         President, Wasatch Operations, MTI2. Judson A. Lovingood, Deputy
         Manager, Shuttle Projects Office, MSFC2. Calvin Wiggins, Vice President and
         General Manager, Space Division, MTI3. Leslie F. Adams, Deputy Manager,
         SRB Project, MSFC3. Joe C. Kilminster, Vice President,
         Space Booster Programs, MTI4. Lawrence O. Wear, Manager, SRM
         Project Office, MSFC4. Robert K. Lund, Vice President,
         Engineering, MTI5. John Q. Miller, Technical
         Assistant, SRM Project, MSFC5. Larry H. Sayer, Director,
         Engineering and Design, MTI6. J. Wayne Littles, Associate
         Director for Engineering, MSFC6. William Macbeth, Manager, Case
         Projects, Space Booster Project Engineering, Wasatch
         Division, MTI7. Robert J. Schwinghamer, Director,
         Material and Processes Laboratory, MSFC7. Donald M. Ketner, Supervisor, Gas
         Dynamics Section and Head Seal Task Force, MTI8. Wilbur A. Riehl, Chief,
         Nonmetallic Materials Division, MSFC8. Roger Boisjoly, Member, Seal Task
         Force, MTI9. John P. McCarty, Deputy Director,
         Structures and Propulsion Laboratory, MSFC9. Arnold R. Thompson, Supervisor,
         Rocket Motor Cases, MTI10. Ben Powers, Engineering
         Structures and Propulsion Laboratory, MSFC10. Jack R. Kapp, Manager, Applied
         Mechanics Department, MTI11. James Smith, Chief Engineer, SRB
         Program, MSFC11. Jerry Burn, Associate Engineer,
         Applied Mechanics, MTI12. Keith E. Coates, Chief Engineer,
         Special Projects Office, MSFC12. Joel Maw, Associate Scientist,
         Heat Transfer Section, MTI13. John Schell, Retired Engineer,
         Materials Laboratory, MSFC13. Brian Russell, Manager, Special
         Projects, SRM Project, MTIPresent at KSC14. Robert Ebeling, Manager, Ignition
         System and Final Assembly, SRB Project, MTI14. Cecil Houston, MSFC Resident
         Manager, at KSCPresent at MSFC15. Stanley R. Reinartz, Manager,
         Shuttle Projects Office, MSFC15. Boyd C. Brinton, Manager, Space
         Booster Project, MTI16. Lawrence B. Mulloy, Manager, SRB
         Project, MSFC16. Kyle Speas, Ballistics Engineer,
         MTIPresent at KSC17. Allan J. McDonald, Director, SRM
         Project, MTI18. Jack Buchanan, Manager, KSC
         Operations, MTI





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[114]Ambiguities In The Decision Making Process

During the night and early morning of January
28, another problem was developing due to the extreme cold weather,
predicted to be in the low 20s for approximately 11 hours. Reaction
control system heaters on the Orbiter were activated and the Solid
Rocket Booster recovery batteries were checked and found to be
functioning within specifications. There were no serious concerns
regarding the External Tank. The freeze protection plan for the
launch pad was implemented, but the results were not what had been
anticipated. The freeze protection plan usually involves completely
draining the water system. However, this was not possible because of
the imminent launch of 51-L. In order to prevent pipes from freezing,
a decision was made to allow water to run slowly from the system.
This had never been done before, and the combination of freezing
temperatures and stiff winds caused large amounts of ice to form
below the 240-foot level of the fixed service structure including the
access to the crew emergency egress slide wire baskets. Ice also was
forming in the water trays beneath the vehicle.

These conditions were first identified by the
Ice Team at approximately 2:00 a.m. on January 28 and were assessed
by management and engineering throughout the night, culminating with
a Mission Management Team meeting at 9:00 a.m. At this meeting,
representatives for the Orbiter prime contractor, Rockwell
International, expressed their concern about what effects the ice
might have on the Orbiter during launch. Rockwell had been alerted
about the icing conditions during the early morning and was working
on the problem at its Downey, California, facility.

During Commission hearings, the president of
Rockwell's Space Transportation Systems Division, Dr. Rocco Petrone,
and two of his vice presidents, Robert Glaysher and Martin
Cioffoletti, all described the work done regarding the ice conditions
and the Rockwell position at the 9:00 a.m. meeting with regard to
launch. Dr. Petrone had arrived at Kennedy on Friday, January 24. On
Monday the 27th he left to return to Rockwell's facility in
California, but Glaysher and Cioffoletti remained at Kennedy. Dr.
Petrone testified that he first heard about the ice at 4:00 a.m.
Pacific Standard Time. He explained what followed:26

> "I had gotten up and went to the
> support room to support this launch. We have people monitoring
> consoles, and I checked in, and they told me there was a concern, and
> when I arrived at about 4:30, 4:40 (PST), I was informed we were
> working the problem with our aerodynamicist and debris people, but
> very importantly, we would have to make an input to Kennedy for a
> meeting scheduled at 6:00 o'clock our time and 9:00 o'clock Florida
> time.
> 
> "We had approximately an hour of work to bring
> together. The work had been underway when I arrived and was
> continuing.
> 
> "At that time I got on the phone with my
> Orbiter program managers just to discuss background of where we were,
> how things stood, and what their concerns were locally. They
> described what they knew in Florida, and we also in Downey did
> television input, and we could see some of the ice scenes that were
> shown here this morning.
> 
> "We arrived through a series of meetings to a
> top level discussion at approximately 5:30 Pacific Standard Time,
> from which we drew the following conclusions: Ice on the mobile
> launcher itself, it could be debris. We were very concerned with
> debris of any kind at the time of launch. With this particular ice,
> one, could it hit the Orbiter? There was wind blowing from the west.
> That appeared not to be so, that it wouldn't hit the Orbiter but
> would land on the mobile launcher. The second concern was what
> happens to that ice at the time you light your liquid fuel engines,
> the SSMEs, and would it throw it around and ricochet and potentially
> hit the Orbiter.
> 
> "The third aspect is the one that has been
> discussed here of aspiration, what would happen when the large SRM
> [Solid Rocket Motors] motors ignite and in effect suck in air,
> referred to as aspiration, and ice additionally would come down, how
> much unknown.
> 
> "The prime thing we were concerned about was
> the unknown base line. We had not launched in conditions of that
> nature, and we just felt we had an unknown.
> 
> "I then called my program managers over in
> Florida at 5:45 (PST) and said we could [115] not recommend
> launching from here, from what we see. We think the tiles would be
> endangered, and we had a very short conversation. We had a meeting to
> go through, and I said let's make sure that NASA understands that
> Rockwell feels it is not safe to launch, and that was the end of my
> conversation . "

Mr. Glaysher, who was at Kennedy, came to the
center at approximately 7:45 a.m. EST. He conferred with Rockwell's
Chief Engineer as well as the Vice President of Engineering, Dr. John
Peller, at Rockwell's Downey plant. At 9:00 a.m., after the ice
debris team had reported back from the pad inspection, Glaysher was
asked for Rockwell's position on launch. He discussed aspiration
effects, the possible ricochet of ice from the fixed service
structure, and what the ice resting on the mobile launch platform
would do at ignition. Glaysher said he told the Mission Management
Team when it met at 9:00 a.m. that the ice was an unknown condition,
and Rockwell was unable to predict where the ice would go or the
degree of potential damage to the Orbiter thermal protection system
if it were struck by the ice. He testified that his recommendation to
NASA was:27

> "[M]y exact quote-and it comes in
> two parts. The first one was, Rockwell could not 100 percent assure
> that it is safe to fly which I quickly changed to Rockwell cannot
> assure that it is safe to fly .

Rockwell's other vice president at Kennedy,
Martin Cioffoletti, described the concern about ice in a slightly
different manner:28



> Mr. Cioffoletti: Similarly, I was called in and told about the problem
> and came into the 6:00 o'clock meeting which you heard about a few
> minutes ago, and at the conclusion of that meeting I spoke with Mr.
> Dick Kohrs, the deputy program manager from Johnson Space Flight
> Center, and he asked if we could get the Downey folks to look at the
> falling ice and how it might reverse toward the vehicle, and also,
> did we have any information on aspiration effects.
> 
> So I did call back to Downey and got the John
> Peller folks working on that problem, and they did, as you saw from
> Charlie Stevenson's sketches, predict that the ice would travel only
> about halfway to the vehicle, freefalling ice carried by the winds.
> So we felt that ice was not a problem. However, it would land on the
> mobile launch platform. That we considered a problem. We also
> investigated the aspiration data base we had, and we had seen the
> aspiration effect on previous launches where things were pulled into
> the SRB [Solid Rocket Booster] hole after ignition, but we had never
> seen anything out as far as the fixed surface tower. So we felt in
> fact it was an unknown. We did not have the data base to operate from
> an aspiration effect.
> 
> At the 9:00 o'clock meeting, I was asked by
> Arnie Aldrich, the program manager, to give him the results of our
> analysis, and I essentially told him what I just told you and felt
> that we did not have a sufficient data base to absolutely assure that
> nothing would strike the vehicle, and so we could not lend our 100
> percent credence, if you will, to the fact that it was safe to fly
> .
> 
> I said I could not predict the trajectory that
> the ice on the mobile launch platform would take at SRB
> ignition.
> 
> Chairman Rogers: But I think NASA's position probably would be that
> they thought that you were satisfied with the launch. Did you convey
> to them in a way that they were able to understand that you were not
> approving the launch from your standpoint?
> 
> Mr. Cioffoletti: I felt that by telling them we did not have a
> sufficient data base and could not analyze the trajectory of the ice,
> I felt he understood that Rockwell was not giving a positive
> indication that we were for the launch.



After Cioffoletti's testimony at the
Commission hearings, Dr. Petrone was pressed for a more detailed
description of Rockwell's launch recommendation:29



> General Kutyna: Dr. Petrone, you've got a lot more experience than I
> have in this business, but the few launch conferences that I have
> been on the question is very simple. Are you go or are you no-go for
> launch, and `` maybe" isn't an answer. I hear all kinds of
> qualifications and cautions and considerations here.
> 
> Did someone ask you are you go or nogo? Was
> that not asked?
> 
> [116]Dr. Petrone: At this
> particular meeting, as far as-and I was not in Florida, and so I
> cannot answer that. It had been done at earlier meetings. This was a
> technical evaluation of a series of problems, and we talked about
> debris hitting the TPS [thermal protection system] and the tiles, and
> the long series of reviews that we had done that morning and all led
> us to a conclusion that they were not safe to fly.
> 
> And we transmitted that to program managers
> along with the technical evaluation quickly of why we had arrived at
> that.
> 
> So much of it is how the question gets raised
> because earlier we had aspiration work, ricochet work, a number of
> things which we did, and then we came up with our
> recommendation.
> 
> Chairman Rogers: And your recommendation now you say it was, it was
> unsafe to fly?
> 
> Dr. Petrone:
> Correct, sir.



Two things are apparent from the Rockwell
testimony. First, Rockwell did not feel it had sufficient time to
research and resolve the ice on the pad problem. Second, even though
there was considerable discussion about ice, Rockwell's position on
launch described above was not clearly communicated to NASA officials
in the launch decision chain during the hours preceding 51-L's
launch.

At a meeting with Commission investigators on
March 4, 1986, at Kennedy, Horace Lamberth, NASA director of Shuttle
Engineering, said he did not interpret Rockwell's position at the
9:00 a.m. Mission Management Team meeting on January 28 as being
"no-go." Lamberth said the the language used by Rockwell was "we
can't give you 100 percent assurance" but there was no feeling in his
mind that Rockwell was voicing a no-go recommendation. "It just
didn't come across as the normal Rockwell nogo safety of flight
issues come across."30This conclusion is confirmed in part by an interview
of Dr. John Peller, Rockwell's Vice President of Engineering, who was
assigned the ice problem early Tuesday morning. Dr. Peller, in
describing a telephone conversation with the Johnson Director of
Engineering, Tom Moser, stated:31



> Dr. Peller: That was a call from Tom Moser to me, in which he
> asked again to understand my concerns. And I just repeated the same
> concerns. And he asked, "Did I think that it was likely that the
> vehicle would take safety critical damage?"
> 
> And I said, "From the possibility that the
> vehicle would take safety critical damage," I said, "there's a
> probability in a sense that it was probably an unlikely event, but I
> could not prove that it wouldn't happen . . ."
> 
> . . . I never used the words "no-go" for
> launch. I did use the words that we cannot prove it is safe. And
> normally that's what we were asked to do. We were unable to do that
> in this particular case, although it was a strange case, that we
> normally don't get involved in.



Arnold Aldrich, NASA Mission Management Team
Leader, described NASA's view of the ice situation and his
recollection of Rockwell's position. He said that on Tuesday morning
the mission management team did a detailed analysis of the ice on the
fixed service structure. Representatives from the ice team, Rockwell,
and the directors of Engineering (Horace Lamberth) and the Orbiter
project (Richard Colonna) all considered the problem. Aldrich
reported this discussion as follows :32

> "Following the discussion of the
> acceptability of the ice threat to the Orbiter, based upon the
> conditions described in detail of the fixed service structure-and
> some of that you've seen here portrayed well this morning-I asked the
> NASA managers involved for their position on what they felt about the
> threat of that to the Orbiter.
> 
> "Mr. Lamberth reported that KSC [Kennedy Space
> Center] engineering had calculated the trajectories, as you've heard,
> of the falling ice from the fixed service structure east side, with
> current 10-knot winds at 300 degrees, and predicted that none of this
> ice would contact the Orbiter during its ignition or launch sequence;
> and that their calculations even showed that if the winds would
> increase to 15 knots, we still would not have contact with the
> Orbiter.
> 
> "Mr. Colonna, Orbiter project manager,
> reported that similar calculations had been performed in Houston by
> the mission evaluation team there. They concurred in this assessment.
> And further, Mr. Colonna stated that, even if these calculations were
> [117]
> significantly in error, that it was their belief that falling ice
> from the fixed service structure, if it were in fact to make its way
> to the Orbiter, it would only be the most lightweight ice that was in
> that falling stream, and it would impact the Orbiter at a very
> oblique angle.
> 
> "Impacts of this type would have very low
> probability of causing any serious damage to the Orbiter, and at most
> would result in post-flight turnaround repairs.
> 
> "At this point I placed a phone call to Mr.
> Moser that I had previously mentioned, director of Engineering at the
> Johnson Space Center, who was in the mission evaluation room, and he
> confirmed the detailed agreement with Mr. Lamberth's and Mr.
> Colonna's position....
> 
> "And both Mr. Lamberth and Mr. Colonna
> reported that their assessment was that the time it took for the ice
> to fall, to hit the Orbiter and to rebound, and the location of the
> fixed service structure on the MLP [mobile launch platform] would not
> cause that ice in their view to be a concern to rebound and come up
> and impact the rear end of the Orbiter.
> 
> "Following these discussions, I asked for a
> position regarding proceeding with the launch. Mr. Colonna, Mr.
> Lamberth, and Mr. Moser all recommended that we proceed.
> 
> "At that time, I also polled Mr. Robert
> Glaysher, the vice president, Orbiter project manager, Rockwell
> International STS Division, and Mr. Marty Cioffoletti, Shuttle
> Integration Project Manager, Rockwell International STS Division. Mr.
> Glaysher stated-and he had been listening to this entire discussion
> and had not been directly involved with it, but had been party to
> this the whole time.
> 
> "His statement to me as best I can reconstruct
> it to report to you at this time was that, while he did not disagree
> with the analysis that JSC (Johnson Space Center) and KSC had
> reported, that they would not give an unqualified go for launch as
> ice on the launch complex was a condition which had not previously
> been experienced, and thus this posed a small additional, but
> unquantifiable, risk. Mr. Glaysher did not ask or insist that we not
> launch, however.
> 
> "At the conclusion of the above review, I felt
> reasonably confident that the launch should proceed."

In addition to Rockwell's input, Mr. Aldrich
also had reports from other contractors and the ice, frost and debris
team at the 9:00 session. Ice on the vehicle assembly appeared to be
of no concern; sheet ice in the noise suppression trays had been
broken up and removed; as previously noted the ice team reported that
there was ice on the fixed service structure between 95 feet above
ground and 215 feet; no ice above 255 feet. The north and west sides
had large amounts of ice and icicles. The final assessment was made
that the ice on the fixed service structure would not strike or
damage the Orbiter tiles or the vehicle assembly during ignition or
ascent, owing to the considerable horizontal distance between the
service structure and the vehicle assembly. The decision was made to
launch pending a final ice team review of the launch complex in order
to assess any changes in the situation. This inspection was completed
following the Mission Management Team meeting and the ice team report
indicated no significant change.



Findings

The Commission is concerned about three
aspects of the ice-on-the-pad issue.

1. An analysis of all of the testimony and
interviews establishes that Rockwell's recommendation on launch was
ambiguous. The Commission finds it difficult, as did Mr. Aldrich, to
conclude that there was a no-launch recommendation. Moreover, all
parties were asked specifically to contact Aldrich or Moore about
launch objections due to weather. Rockwell made no phone calls or
further objections to Aldrich or other NASA officials after the 9:00
Mission Management Team meeting and subsequent to the resumption of
the countdown.

2. The Commission is also concerned about the
NASA response to the Rockwell position at the 9:00 a.m. meeting.
While it is understood that decisions have to be made in launching a
Shuttle, the Commission is not convinced Levels I and II
appropriately considered Rockwell's concern about the ice. However
ambiguous Rockwell's position was, it is clear that they did tell
NASA that the ice was an unknown condition. Given [118] the extent of the
ice on the pad (see photos pages 112 and 113), the admitted unknown
effect of the Solid Rocket Motor and Space Shuttle Main Engines
ignition on the ice, as well as the fact that debris striking the
Orbiter was a potential flight safety hazard, the Commission finds
the decision to launch questionable under those circumstances. In
this situation, NASA appeared to be requiring a contractor to prove
that it was not safe to launch, rather than proving it was safe.
Nevertheless, the Commission has determined that the ice was not a
cause of the 51-L accident and does not conclude that NASA's decision
to launch specifically overrode a no-launch recommendation by an
element contractor.

3. The Commission concluded that the freeze
protection plan for launch pad 39B was inadequate. The Commission
believes that the severe cold and presence of so much ice on the
fixed service structure made it inadvisable to launch on the morning
of January 28, and that margins of safety were whittled down too
far.

Additionally, access to the crew emergency
slide wire baskets was hazardous due to ice conditions. Had the crew
been required to evacuate the Orbiter on the launch pad, they would
have been running on an icy surface. The Commission believes the crew
should have been made aware of the situation, and based on the
seriousness of the condition, greater consideration should have been
given to delaying the launch.



[119]References