Word: seale
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Dates: during 1980-1989
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...tracked the O-ring problem on paper since 1978, some three years before the first shuttle flight, on April 12, 1981. As early as Jan. 19, 1979, John Q. Miller, chief of the solid motor branch at Marshall, where the boosters were developed, complained to his superiors that the seal was functioning "in a way which violates industry and Government O-ring application practices." On May 29, 1980, a NASA engineering panel noted that the O rings had failed in a ground test and called them "inadequate" for reliability and "marginal" in their safety. On Feb. 28, 1984, Miller warned...
What did NASA do about its problem? Not much, even though boosters recovered after several flights showed O-ring erosion, indicating that the hot gases were reaching them and threatening to burn through the seal. NASA did ask its booster contractor, Morton Thiokol, to seek a solution. Thiokol set up a seal task force at its plant in Utah. This work received more attention after a shuttle was launched on Jan. 24, 1985, following the coldest overnight cape temperature of any flight to date: in the 20s. This launch produced the most extensive ring damage. Morton Thiokol concluded...
While the search for a fix proceeded, Bob Ebeling, manager of the booster- ignition system at Morton Thiokol, wrote a plaintive interoffice memo on Oct. 1, 1985, saying, "HELP! The seal task force is constantly being delayed by every possible means . . . The allegiance to the O-ring investigation task force is very limited to a group of engineers numbering 8-10 . . . We wish we could get action by verbal request, but such is not the case. This is a red flag...
There was yet another roadblock to action: despite the documents, top flight officials at Marshall, including Mulloy, believed that the seal had redundancy in the critical early stages of ignition. Dutifully, however, Mulloy slapped a formal launch constraint on the joint problem. That meant that there could be no shuttle flight until the seal was fixed. But few above Mulloy even knew the constraint existed; worse yet, having imposed the restraint, Mulloy routinely waived it before each launch. So the shuttles flew, its astronauts innocently unaware of the lingering joint danger...
...joint's troubled history was completely dismissed on the eve of Challenger's launch. The seals had long been flagged as a problem that could be aggravated by low temperatures. Yet George Hardy, Marshall's deputy director of science and engineering, declared that he was "appalled" by Thiokol's reasoning that the cape's cold weather, predicted to be in the 30s at lift-off, should lead to a delay. In the now notorious teleconference, four Thiokol vice presidents at first concurred with the fears of their engineers. But when they heard the NASA objections, they decided to take...