On Mon, 7 Mar 2016 20:28:13 -0800 (PST), Stuf4
wrote:

From Jeff Findley:
In article ,
says...

Contrary to popular opinion...
The SRB design was actually adequate.

This is absolutely, completely, false.

They worked successfully on 24 flights. That's 48 successful SRB
burns in flight. What proved fatal was not the o-ring design. What
killed the astronauts was failure to respect the design limits.

Again, this is incorrect.

There was actually ample evidence before Challenger that the field joint
was not safe. The o-rings were *never* designed to come into contact
with combustion gases, yet it had happened on *several* flights *before*
Challenger. In fact, that data is what prompted the Thiokol engineers
to recommend *not* launching Challenger on that frigid morning.

If the position that you & Greg are espousing was accurate,
then Thiokol would have *never* recommended a launch.

They were more worried about losing the lucrative SRB contract to
United Technologies (which made Titan SRMs at the time.) Going to NASA
and saying "we have to stop all launches and redesign the field joint,
oh and that's going to take 2-3 years" takes more courage than most
people have. Thiokol wouldn't do that, because they feared massive
financial penalties from not flying for 2-3 years, or possibly losing
the contract to a competitor, or even worse, see the Shuttle program
killed by Congress. NASA wouldn't do that because they'd have to tell
Congress their Shuttle couldn't fly for 2-3 years. Congress would very
likely have killed the program then and there, as Shuttle had a large
number of critics on the Hill.

And remember, the SRB design had been flawed all along, but it had
never actually failed. They'd gotten away with it every time so far,
and management had convinced itself they'd get away with it again.

They didn't.

Brian