[Bobby777]

well then, why was Challenger launched when the boosters were outside the design limits on temperature? ... they checked the vehicle with a hand-held gun but the Thiokol engineers said it was too cold to launch, and that the O-rings would not seat properly at that temperature ... there had already been more than 2 instances where the recovered boosters showed significant burn damage to the rings ...

so Vandenburg equipped their pad with jet engines to heat the shuttle after that accident ... why were the Thiokol engineers ignored?

[John Jamieson]

One Thiokol engineer objected and his boss overrid his objection. The engineer was right and I have a lot of respect for him, but the temperature was probably not the issue, just the o rings. He was actual right for the wrong reason. People do the best they can. Perfection should not be expected when pushing the envelop. Atleast one person objects about every launch. The problem list that managers work is 100's long.