Comment by voidUpdate
6 days ago
Using the same o-rings afterwards is surprising, I've heard that the manufacturer was surprised that they were being used for that purpose because they weren't rated for that.
Also I'm not sure the assertion is correct. If the sealant and O-Rings were adequate, the joint would not have failed. It was suboptimal, and increased risk, sure, but it in itself wasn't the reason for the accident. It was the joint and the o-rings in combination. The holes in the swiss cheese model lined up that day, and a lot of small problems combined into one big problem
>> Using the same o-rings afterwards is surprising, I've heard that the manufacturer was surprised that they were being used for that purpose because they weren't rated for that.
Not surprising if you understand what the real cause was: https://news.ycombinator.com/item?id=47585889
Surprised? One of the engineers was literally on the phone with NASA the morning of the disaster begging them not to launch. He was overruled by management.
Surprising for the management. If you are a spoiled brat who always got what it wanted if you just asked/cried you don't expect reality to come and hit you.
Actually, not surprising.
The engineering was clear: don't fly. But given political realities had they said that they probably would have lost the contract to build the rockets--and that was a big part of their business.
They made the human choice: chose the option with a chance of success vs the option that was a certain failure.
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> If the sealant and O-Rings were adequate, the joint would not have failed.
That assertion requires some reasoning and evidence to back it.
The sealant and O-rings were meant to keep the hot gasses inside. Simply making a joint slightly wiggly will not keep hot gasses inside. The hot gasses did not stay inside. The sealant and O-rings did not succeed in keeping the hot gasses inside (evidence: Challenger). They were not adequate
> The sealant and O-rings did not succeed in keeping the hot gasses inside (evidence: Challenger). They were not adequate
No. The whole assembly --joint, sealant and O-rings, -- failed.
"They were not adequate" - yet, after the redesign, they kept those same O-rings and declared that boosters are safe to fly, in manifest contradiction to your assertion. So your reasoning is clearly flawed.
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