[bonesmccoy]

"Heaviest reentry ever"

Is that correct?

You may be right. OV-102 is the most massive orbiter in the fleet. Spacelab missions tend to be a massive payload.

The mass of the vehicle translates to greater heating loads on reentry.

The mass characteristic of the mission is compared to the flight trajectory and the mission is flown after many months of data analysis by the NASA-contractor team.

That analysis includes analysis of abort profiles on lift-off and various landing profiles to different runways.

I am certain that the analysis was carried out.

The problem is really that the TPS was damaged. Jim is correct regarding the odds of a flight problem. I am not a safety expert and can not calculate the probability of failure.

The issue is that the risk could be 99.9% safety margin. That means a 1/1000 risk. That risk could bite you. In order to get a system that has 1/10,000 risk, it would cost the nation an extra billion dollars. Is that worth it?

Only politicians know.

[Cold Heat]

The mass of the vehicle translates to greater heating loads on reentry.

I would agree that the total heat generated would be greater due to a required longer re-entry(more s-turns to scrub off the speed), however the craft would likely not experience substantialy more heat at any one time during the decent, just a longer time at high heat.

Am I close to correct? Or am I mis-understanding the process.

[Jim Noble]

>>The issue is that the risk could be 99.9% safety margin. That means a 1/1000 risk. That risk could bite you. In order to get a system that has 1/10,000 risk, it would cost the nation an extra billion dollars. Is that worth it? <<

Is it worth it for flight test? Probably not.

Is it worth it for a system designed for flight rates of 1/month in order to be cost justified? Almost certainly.

The STS was sold to a (venal, whorish, ground-looking) Congress under false pretenses. I understand that if Congress didn't let the shuttle fly we wouldn't fly at all.

Ordinarily, I'm a "half a loaf is better than none" guy.

But this half loaf's design can't sustain it's mission, IMO, which is not to flight test experimental TPS designs but to put stuff and people in space, and bring the people back.

[John Jamieson]

This was not a "SpaceLab" mission, but the first "Double SpaceHab" mission which I figure at 30,000 pounds plus.