Shuttle Surface More Vulnerable Than Suspected

Ant writes "The space shuttle's skin is turning out to be even more fragile than NASA engineers thought, its scientists and engineers say. Impact tests and analysis performed as part of the return-to-flight effort show that pieces of insulating foam that weigh less than half an ounce can cause small cracks and damage to the surface coating on the heat-resistant panels on the leading edge of the wing, agency officials said in interviews this week."

Comments

Re:Aging?

[Cecil]

I don't think aging has much to do with it. As I recall, most of the surface components are replaced after each mission and everything is thoroughly inspected for defects/weaknesses.

My question would be whether the replacement tiles are actually new, or whether they've just been sitting in a warehouse for 40 years like most of the other shuttle spare parts.

The foam issue is something NASA had known about for a while before the Columbia disaster, they just hadn't taken it seriously enough. Kind of the same thing as what happened with Challenger where they knew about the o-ring issue but didn't take it seriously enough either.

It's easy to say in hindsight that they didn't take it seriously enough. But in reality, it's hard to tell which things need to be taken seriously and which are trivial. And you can't just assume everything is serious -- if you take everything seriously, you're never going to get *anything* done. NASA is and always was way, way, way on the 'better safe than sorry' end of the spectrum, even at the time of the O-ring and foam problems. But they have to draw the line at some point, due to the law of diminishing returns. I think they've gone beyond that line in the aftermath of Columbia, personally.