NASA Recovers Columbia Cockpit Videotape

AP ^ | February 25, 2003 | MARCIA DUNN

[Positive]

"A "black box" is designed to survive a crash at hundreds of MPH, not thousands of MPH. A regular aircraft CVR or FDR would not have survived the catastrophic destruction of the shuttle. An airplane lawn-darting into the ground is one thing, but a shuttle returning from orbit at Mach 18 is a whole different problem.

Actually the shuttle didn't crash at thousands of MPH. It crashes at no greater speed than "an airplane lawn-darting into the ground." The terminal velocity of a falling body occurs during free fall when a falling body experiences zero acceleration. This is because of the retarding force known as air resistance. Air resistance exists because air molecules collide into a falling body creating an upward force opposite gravity. This upward force will eventually balance the falling body's weight. It will continue to fall at constant velocity known as the terminal velocity.

The shuttle was "slowing down" until it reached terminal velocity, by which time it had broken up and therefore was almost certainly falling slower than and "airplane lawn darting."

[Ramius]

Understood. But few airplanes come apart at Mach 18.

Sure, the parts will slow down quickly, but the violence of the breakup is easily underestimated.

[Jael]

Shuttle news bump!

[Jael]

Shuttle news ping.

[TLBSHOW]

Thanks!

[aristeides]

Body parts survived.

[aristeides]

For the money we spend, these guys need to be going the extra mile on disaster insurance.

I have yet to see any plausible excuse for adding the added weight of the new Space Hab 2 lab. None of the experiments conducted sound as if they were that vital.

[no-s]

...any plausible excuse for adding the added weight of the new Space Hab 2

I only gave this a cursory glance, but it sounds like the lifting/reentry surface loading was close to unexplored territory. Plus Gibson says Columbia was prone to early turbulent flow transitions.

Extra wing loading + turbulent flow + tile/seal damage...hmm. Might be some investigation due there.

Over on the TPS damage thread there are some ex-rockwell geeks debating the tile damage, with models and charts and all.

[Fred Mertz]

Thanks for the heads up.

[Joe Hadenuf]

You bet......

[Balding_Eagle]

A regular aircraft CVR or FDR would not have survived the catastrophic destruction of the shuttle.

Then how did the videotape survive? It would seem that videotape would be even less likely to survive.

[js1138]

Remember all the fires, blackouts, computer failure, collision etc happening on Mir?

The really great one on MIR was the oxygen generator the fired off. That's the thing that brought down the Valuejet. In space no less. And they survived.

[Ramius]

hmmm... OK. Fair point.

But what remains is that the shuttle, via telemetry data, has in most cases far more datapoints gathered than an ordinary airliner, at least as far as a FDR is concerned.

A CVR might be interesting, but I have to admit at this point that it might merely be macabre. At mach 18 when things go badly, they go badly so fast that I wouldn't think that a CVR would likely provide any useful data.

At least, I hope so. I would hope that it went that way.