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The soccer ball that survived the Challenger explosion

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Re: The soccer ball that survived the Challenger explosion

#31

Post by oh_sigh »

0xffff2 wrote: post #28
jedberg wrote: post #24

Earlier quoted context omitted.

I'm not a rocket scientist so I might be wrong, but I'm pretty sure the O ring would be required no matter how it was constructed.

Why do you think that? As the person you replied to said, the only reason the O-ring is there at all is to seal the joint between the sections. If the join't didn't exist, there would be no reason at all for there to be a rubber ring embedded in the structure.

And if the politicians didn't vote to build the SRBs in Utah, then maybe there would be no SRB at all, which is a good method to prevent deaths from SRBs.

Re: The soccer ball that survived the Challenger explosion

#32

Post by T-hawk »

mehrdadn wrote: post #26
rmason wrote: post #23

I was visiting farmers reviewing plans for the next crop year. I'd just arrived and the farmer says do you mind if we watch the Challenger launch before starting? It's got that teacher going up in space. I told him that my high school government teacher had been one of the ten finalists so I took a pretty keen interest myself. I can remember the numbness I felt in his living room as we watched the Challenger explode.…

> The night before the launch, Ebeling and four other engineers had tried to stop the launch. Their managers and NASA overruled them. That night, he told his wife, "It's going to blow up." This sent chills down my spine... the world just shouldn't be like this.

One important piece of data to correlate with that: how many times previously had engineers issued similar warnings for launches that then proceeded fine?

Warning fatigue is a thing and reasonable to wonder whether that happened at all here.

Re: The soccer ball that survived the Challenger explosion

#33

Post by mehrdadn »

T-hawk wrote: post #32
mehrdadn wrote: post #26

Earlier quoted context omitted.

> The night before the launch, Ebeling and four other engineers had tried to stop the launch. Their managers and NASA overruled them. That night, he told his wife, "It's going to blow up." This sent chills down my spine... the world just shouldn't be like this.

One important piece of data to correlate with that: how many times previously had engineers issued similar warnings for launches that then proceeded fine? Warning fatigue is a thing and reasonable to wonder whether that happened at all here.

Yeah, very true. I did wonder about that a bit, and also how dire the previous warnings were, if any. "It's going to blow up" sounds like something that a good engineer shouldn't be saying very often about successful flights.

Re: The soccer ball that survived the Challenger explosion

#34

Post by madrox »

runciblespoon wrote: post #7

"the solid rocket boosters ignited and somewhere in the right booster, a 0.280-inch-wide O-ring failed due to the cold." The 'solid rocket boosters' being constructed in segments because they had to be transported by rail from Utah. They had to be constructed in that state as part of the deal to get the politicians to vote in the finances.

The post hoc ergo propter hoc going on in this comment and its responses are wild.

The O-ring failed because it was a bad O-ring, and no one in positions that matters appreciated it was a bad O-ring. Politicizing it into a witch hunt to make congress look bad doesn't do anyone favors. It just feeds existing rage.

Re: The soccer ball that survived the Challenger explosion

#35

Post by greglindahl »

runciblespoon wrote: post #7

"the solid rocket boosters ignited and somewhere in the right booster, a 0.280-inch-wide O-ring failed due to the cold." The 'solid rocket boosters' being constructed in segments because they had to be transported by rail from Utah. They had to be constructed in that state as part of the deal to get the politicians to vote in the finances.

Segmented SRBs are used on Ariane 5 and Northrop Grumman's upcoming Omega rocket, while Vega, Vega-C, and Ariane 6 will use a single-segment SRB. It's a choice that was dictated by politics for the Shuttle, but it's also a choice that can be made for other reasons, like a smaller composite segment using a cheaper tool (Omega and the Boeing 787 fuselage tube).

Re: The soccer ball that survived the Challenger explosion

#36

Post by 0xffff2 »

oh_sigh wrote: post #31
0xffff2 wrote: post #28

Earlier quoted context omitted.

Why do you think that? As the person you replied to said, the only reason the O-ring is there at all is to seal the joint between the sections. If the join't didn't exist, there would be no reason at all for there to be a rubber ring embedded in the structure.

And if the politicians didn't vote to build the SRBs in Utah, then maybe there would be no SRB at all, which is a good method to prevent deaths from SRBs.

Okay... how is that relevant to my comment at all?

Re: The soccer ball that survived the Challenger explosion

#37

Post by jedberg »

0xffff2 wrote: post #28
jedberg wrote: post #24

Earlier quoted context omitted.

I'm not a rocket scientist so I might be wrong, but I'm pretty sure the O ring would be required no matter how it was constructed.

Why do you think that? As the person you replied to said, the only reason the O-ring is there at all is to seal the joint between the sections. If the join't didn't exist, there would be no reason at all for there to be a rubber ring embedded in the structure.

Because that spot on the SRB is a flex joint to allow some movement of the nozzle as the engine fires. The joint isn't there because of transportation or other reasons.

Re: The soccer ball that survived the Challenger explosion

#38

Post by giodamelio »

jedberg wrote: post #6

> You may not know it, but you carry some of his words with you in your own earthly exploration, printed in every U.S. passport. This whole article was fantastic, but this was the coolest part for me. To learn that his quote is on every passport. I've never read the quotes on my passport before, but now I have.

Exactly. That was a chills down the the spine moment.

I will definitely be taking a closer look at the quotes in my passport when I get home today.

Re: The soccer ball that survived the Challenger explosion

#39

Post by robryk »

jedberg wrote: post #37
0xffff2 wrote: post #28

Earlier quoted context omitted.

Why do you think that? As the person you replied to said, the only reason the O-ring is there at all is to seal the joint between the sections. If the join't didn't exist, there would be no reason at all for there to be a rubber ring embedded in the structure.

Because that spot on the SRB is a flex joint to allow some movement of the nozzle as the engine fires. The joint isn't there because of transportation or other reasons.

That spot was the "aft field joint" according to wikipedia. According to the diagram linked[1] that is distinct from the case-to-nozzle joint.

[1] https://science.ksc.nasa.gov/shuttle/technology/sts-newsref/...

Re: The soccer ball that survived the Challenger explosion

#40

Post by londons_explore »

T-hawk wrote: post #32
mehrdadn wrote: post #26

Earlier quoted context omitted.

> The night before the launch, Ebeling and four other engineers had tried to stop the launch. Their managers and NASA overruled them. That night, he told his wife, "It's going to blow up." This sent chills down my spine... the world just shouldn't be like this.

One important piece of data to correlate with that: how many times previously had engineers issued similar warnings for launches that then proceeded fine? Warning fatigue is a thing and reasonable to wonder whether that happened at all here.

In some working environments issuing a warning is enough to get you off the hook for something going wrong, so it might be that nearly every flight had a warning so the engineers were never responsible...
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