| Roger Boisjoly | |
|---|---|
| Born | April 25, 1938 |
| Residence | Mesquite, Nevada, United States |
| Citizenship | American |
| Nationality | American |
| Fields | Engineering (Mechanical) |
| Institutions | Morton Thiokol |
| Known for | Challenger Disaster |
| Notable awards | Scientific Freedom and Responsibility (2006) |
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Notes
He was the project manager of the solid fuel boosters of the Shuttle Program System. |
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Roger M. Boisjoly (born April 25, 1938) is a mechanical engineer, fluid dynamicist and an aerodynamicist who worked for Morton Thiokol, the manufacturer of the solid rocket boosters for the Space Shuttle program. He is best known for raising objections to the launch of the Space Shuttle Challenger the day before the loss of the spacecraft and its crew.
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Boisjoly wrote a memo in July 1985 to his superiors concerning the faulty design of the solid rocket boosters that, if left unaddressed, could lead to a catastrophic event during launch of the Space Shuttle. Such a catastrophic event did occur less than a year later during the Space Shuttle Challenger disaster.
This memo followed his investigation of a Solid Rocket Booster from a shuttle flight in January 1985. During his investigation, he discovered that the first of a system of 2 O-Rings had failed completely, and that some damage had been caused to the second O-Ring.
The O-Rings were two rubber rings that formed a seal between two sections of the Solid Rocket Boosters. The sections of the boosters were joined using tang and clevis joints and the rings were intended to seal the joint, while allowing for the inevitable movement between the sections under flight conditions. The pressure from within the booster pushed a fillet of putty into the joint, which forced the O-Ring into its seat. The rings never functioned according to design. They were supposed to sit in a groove and seal the joint between the sections of the booster. It was found, however, that the pressure of the burning rocket fuel caused the joints in the SRB's to flex during launch, opening a gap through which rocket exhaust could escape. As the joints flexed, the rings would come out of their grooves and move to a new position in the joint, a process called extrusion. The extruded ring would form a seal in this new position, but during the time it took for the ring to shift, the joint was unsealed and hot gasses could escape, a process called blow-by. These hot gasses would cause damage to the rings until the seal was achieved.
What Boisjoly's investigation showed was that the amount of damage to the O-Ring depended on the length of time it took for the ring to move out of its groove and make the seal, and that the amount of time depended on the temperature of the rings. Cold weather made the rubber hard and less flexible, meaning that extrusion took more time and more blow-by took place. He determined that if the O-rings were damaged enough they could fail.
If the second O-Ring had failed, Boisjoly realized, the results would almost certainly have been catastrophic with the complete loss of the shuttle and crew seemingly the only outcome. His investigation found that the first O-ring failed because of the low temperatures on the night before the flight had compromised the flexibility of the O-Ring, reducing its ability to form a seal. The temperature at launch had been only 10 °C – the coldest on record (until January 28, 1986). The first rubber O-ring had formed a partial seal, but not a complete one, but fortunately the second O-ring had held.
Boisjoly sent a memo, describing the problem to his managers, but was apparently ignored. It is true that Morton Thiokol were in discussions with NASA with regards to a new contract (reportedly worth up to $1 Billion) and it is possible that the management were concerned that any issues discovered with the Solid Rocket Boosters may compromise the chances of the contract being renewed.
Following several further memos, a "task force" was set up – including Boisjoly – to investigate the matter, but after a month Boisjoly realized that the task force had no power, no resources and no management support.
Eventually, in late 1985 Boisjoly advised his managers that if the problem was not fixed, there was a distinct chance that a shuttle mission would end in disaster. No action was taken.
Following the announcement that the Challenger mission was confirmed for January 28, 1986, Boisjoly and his colleagues tried to stop the flight. Temperatures were due to be down to −1 °C overnight. Boisjoly felt that this would severely compromise the safety of the O-Ring, and potentially lose the flight.
The matter was discussed with Morton Thiokol management, who agreed that the issue was serious enough to recommend delaying the flight. They arranged a telephone conference with NASA management and gave their findings. However, after a while, the Morton Thiokol managers asked for a few minutes off the phone to discuss their final position again. Despite the efforts of Boisjoly and others in this off-air briefing, the Morton Thiokol managers decided to advise NASA that their data was inconclusive. NASA asked if there were objections. Hearing none, the decision to fly the ill-fated STS-51L Challenger mission was made.
Boisjoly's concerns proved correct. In the first moments after ignition, the O-rings failed completely and were burned away, resulting in the black puff of smoke visible on films of the launch. This left only a layer of aluminum oxide (a combustion product) to seal the joint. At 59 seconds after launch, buffeted by high-altitude winds, the oxide gave way. Hot gases streamed out of the joint in a visible torch-like plume that burned into the external hydrogen tank. At about 73 seconds, the adjacent SRB strut gave way and the vehicle quickly disintegrated.
Boisjoly was quite relieved when the flight lifted off, as his investigations had predicted that the SRB would explode during the initial take-off. Seventy-three seconds later he witnessed the shuttle disaster on television.
After Ronald Reagan ordered a Presidential Committee to review the disaster, Boisjoly was one of the witnesses called. He gave accounts of how and why he felt the O-Rings had failed. After the Committee gave its findings, Boisjoly found himself shunned by colleagues and managers and he resigned from the company.
Boisjoly became a speaker on workplace ethics.[1] He argues that the caucus called by Morton Thiokol managers, which resulted in a recommendation to launch, "constituted the unethical decision-making forum resulting from intense customer intimidation."[2]
For his honesty and integrity leading up to and directly following the shuttle disaster, Boisjoly was awarded the Prize for Scientific Freedom and Responsibility by the American Association for the Advancement of Science.[1]
When Boisjoly left Morton Thiokol, he took 14 boxes of every note and paper he received or sent in seven years. On May 13, 2010 he donated his personal memorandum- six boxes of personal papers, including memos and notes from Congressional testimony to Chapman University in Orange, Ca. Rand Boyd, the special-collections and archival librarian at Chapman's Leatherby Libraries, said the materials will be catalogued and archived. It will be about six months to a year before library visitors will be able to view the materials.