Debris Seen Falling Off Shuttle During Launch

kushboy writes "According to an article on CNN.com, there is video of debris falling off Discovery during its launch earlier today. While the debris does not appear to hit the shuttle, extra precaution and more video will be analyzed due to the Columbia mission of 2003. 'NASA has taken steps to minimize the amount and size of debris falling off the shuttle's exterior tank during its ascent. But the space agency has said it's impossible to eliminate falling launch debris.'"

Comments

I'll feed the troll.

[jd]

The wings are not pressurized, but will leak at a fairly constant rate. Let's call it R. Now, a wing with a bloody great hole in it will also leak at a constant, but different, rate. Let's call it R'. It does not matter what R' is, only that it is strictly greater than R.

So, you have a simple pressure guague and measure the difference between observed pressure drop and your expected value of R. If the total discrepency exceeds some critical threshold, then there is a problem with the wing that would create a serious problem.

Now, measuring the temperature. There's this thing called a thermocouple. Dunno if you've come across these. It requires a couple of strands of wire, which you can run down the length of the wing quite easily. Alternatively, find a piece of metal in the wing that joins to a piece of metal that runs into the cockpit. Two types of metal, a temperature gradient, sounds like a cheapskate peltier device to me. Check the potential difference and you can detect unusual gradients with minimal effort.

Rescue mission: Uh, NASA themselves said that if there was a problem with launch that they would have Atlantis on standby for a rescue mission. Drudge might not have said it, but I don't give a damn about Drudge. I do give a damn about NASA's own statements.

The fact is, I've worked there and know how NASA operates. I know several of the contractors who build components for the shuttle. I've seen round their workshops, I've talked with their engineers. This doesn't sound like a lack of knowledge to me.

I don't need to defend myself in the face of those who really do know less than me, or even less than those who merely read the newspapers and bother to remember what was said by the people involved.

I don't need to defend how much I know. Repeatedly, as none of this is unique to this posting, I've said all of this in prior Shuttle and/or NASA debates when people have asked for my sources. Why should I keep telling people stuff that they could have looked up for themselves? All my postings are searchable on Google, same as everyone else's. If you wanted to know the extent of my knowledge, you wouldn't need to troll for it.

Can I prove I worked at NASA? Sure. You'll find my old NASA e-mail address on a number of Open Source projects I helped out with at the time. You don't know what those are? Seek and ye shall find. It's not hard to figure out.

Let's see. So, I have inside knowledge of the engineers, inside knowledge of the construction of the Shuttles, and inside knowledge of the political machinations of NASA. And I am the one with the faulty assumptions, working from knowledge I don't have?

Re:I'll feed the troll.

[georgewilliamherbert]

The wings are not pressurized, but will leak at a fairly constant rate. Let's call it R. Now, a wing with a bloody great hole in it will also leak at a constant, but different, rate. Let's call it R'. It does not matter what R' is, only that it is strictly greater than R.

So, you have a simple pressure guague and measure the difference between observed pressure drop and your expected value of R. If the total discrepency exceeds some critical threshold, then there is a problem with the wing that would create a serious problem.

Maybe you should have studied harder when you were with the NASA people you worked with.

The Shuttle wing sections are unpressurized (true) and are faced with solid metal sheets that form the wing structural skin. The thermal protection system goes over those metal sheets. You can completely remove all the tiles and not change the structural integrity of the underlying metal skin.

None of the prior damage in tiled areas punctured the skins.

The leading edge areas with the reinforced carbon-carbon segments are outside the main wing skin. They aren't sealed either, and generally retain very little pressure differential with the outside. It's possible that you'd have seen an abnormally fast equalization of pressure in the Columbia leading edge. But all that tells you is if you have a hole so bad that you're going to lose the shuttle, with no chance of repair.

Most damage will be less severe than that, and such a pressure test won't catch that more minor damage. To find that you have to look at the surface up close to check for dings and cracks.

If you have to visually inspect to check for the more minor but still potentially lethal damage, why even bother with the huge hole pressure check? It's not like the visual inspection can possibly miss an 8" hole in the leading edge with a camera two meters away.