the Challenger Episode


Morton Thiokol, Inc., an aerospace company, manufactures the solid propellant rocket motors for the Peacekeeper missile and the missiles on Trident nuclear submarines. Thiokol also worked closely with the National Aeronautics and Space Administration (NASA) in developing the Challenger, one of NASA's reusable space shuttles.

Specifically, Morton Thiokol manufactured the booster rockets used to launch the Challenger. For January of 1986, NASA had scheduled a special launch of the Challenger. The launch was highly publicized because NASA had conducted a nationwide search for a teacher to send on the flight. On this, NASA's twenty-fifth shuttle mission, teacher Christa McAuliffe would be on board.

On the scheduled launch day, January 28, 1986, the weather was cloudy and cold at the John F. Kennedy Space Center in Cape Canaveral, Florida. The launch had already been delayed several times, but NASA officials still contacted Thiokol engineers in Utah to discuss whether the shuttle should be launched in such cold weather. The temperature range for the boosters, as specified in Thiokol's contract with NASA, was between 40 degrees F and 90 degrees F.

However, the temperature at Cape Canaveral that January morning was below 30 degrees F. The launch of the Challenger proceeded nevertheless. A presidential commission later concluded, "Thiokol management reversed its position and recommended the launch of [the Challenger] at the urging of [NASA] and contrary to the views of its engineers in order to accommodate a major customer."

Two of the Thiokol engineers involved in the launch, Allan McDonald and Roger Boisjoly later testified that they had opposed the launch. Boisjoly had done work on the shuttle's booster rockets at the Marshall Space Flight Center in Utah in February 1985, at which time he noted that at low temperatures, an O-ring assembly in the rockets eroded and, consequently, failed to seal properly.

Though Boisjoly gave a presentation on the issue, little action was taken over the course of the year. Boisjoly conveyed his frustration in his activity reports. Finally, in July 1985, Boisjoly wrote a confidential memo to R. K. (Bob) Lund, Thiokol's vice president for engineering. An excerpt follows: [blockquote]This letter is written to insure that management is fully aware of the seriousness of the current O-ring erosion problem.... The mistakenly accepted position on the joint problem was to fly without fear of failure.... [This position] is now drastically changed as a result of the SRM [shuttle recovery mission] 16A nozzle joint erosion which eroded a secondary O-ring with the primary O-ring never sealing. If the same scenario should occur in a field joint (and it could), then it is a jump ball as to the success or failure of the joint....The result would be a catastrophe of the highest order--loss of human life.... It is my honest and real fear that if we do not take immediate action to dedicate a team to solve the problem, with the field joint having the number one priority, then we stand in jeopardy of losing a flight along with all the launch pad facilities.[/blockquote] In October of 1985, Boisjoly presented the O-ring issue at a conference of the Society of Automotive Engineers and requested suggestions for resolution.

On January 27, 1986, the day before the launch, Boisjoly attempted to halt the launch. However, four Thiokol managers, including Lund, voted unanimously to recommend the launch. One manager had urged Lund to "take off his engineering hat and put on his management hat." The managers then developed the following revised recommendations. Engineers were excluded from the final decision and the development of these findings. [ul][*]Calculations show that SRM-25 [the designation for the Challenger's January 28 flight] O-rings will be 20 degrees colder than SRM-15 O-rings[*]Temperature data not conclusive on predicting primary O-ring blow-by[*]Engineering assessment is that: Colder O-rings will have increased effective durometer [that is, they will be harder][*]"Harder" O-rings will take longer to seat. More gas may pass primary [SRM-25] O-ring before the primary seal seats (relative to SRM-15). Demonstrated sealing threshold [on SRM-25 O-ring] is 3 times greater than 0.038" erosion experienced on SRM-15[*]If the primary seal does not seat, the secondary seal will seat. Pressure will get to secondary seal before the metal parts rotate; O-ring pressure leak check places secondary seal in outboard position which minimizes sealing time[*]MTI recommends STS-51L launch proceeds on 28 January 1986. SRM-25 will not be significantly different from SRM-15.[/ul] After the decision was made, Boisjoly returned to his office and wrote in his journal: [blockquote]I sincerely hope this launch does not result in a catastrophe. I personally do not agree with some of the statements made in Joe Kilminster's [Kilminster was one of the four Thiokol managers who voted to recommend the launch] written summary stating that SRM-25 is okay to fly.[/blockquote] Seventy-four seconds into the Challenger launch, the low temperature caused the seals at the booster rocket joints to fail. The Challenger exploded, killing Christa McAuliffe and the six astronauts who were on board.

The subsequent investigation by the presidential commission placed the blame for the faulty O-rings squarely with Thiokol. Charles S. Locke, Thiokol's CEO, maintained, "I take the position that we never agreed to the launch at the temperature at the time of the launch. The Challenger incident resulted more from human error than mechanical error. The decision to launch should have been referred to headquarters. If we'd been consulted here, we'd never have given clearance, because the temperature was not within the contracted specs."

Both Boisjoly and McDonald testified before the presidential panel regarding their opposition to the launch and the decision of their managers (who were also engineers) to override their recommendation.

Both Boisjoly and McDonald also testified that following their expressed opposition to the launch and their willingness to come forward, they had been isolated from NASA and subsequently demoted. Since testifying, McDonald has been assigned to "special projects." Boisjoly, who took medical leave for post-traumatic stress disorder, has left Thiokol, but he does receive disability pay from the company.

Currently, Mr. Boisjoly operates a consulting firm in Mesa, Arizona. He speaks frequently on business ethics to professional organizations and companies.

In May 1986, then-CEO Locke stated, in an interview with the Wall Street Journal, "This shuttle thing will cost us this year 10 cents a share." Locke later protested that his statement had been taken out of context.