NASA Test Shows Foam Could Be Culprit

Ben Hutchings writes "The BBC has a report on an impact simulation that aimed to recreate the impact of insulating foam on Columbia's wing. The result was a large hole that probably could not be repaired in orbit even if it was known about."

Comments

I wondered the same thing...

[Vellmont]

If you toss a baseball out of a car window when you're driving at 100 mph the ball isn't going to slow down to 0 by the back of the car. It maybe will loose 100 mph in comparison to the shuttle by the time it decelerates a bit from where it broke off to where it hits the wing. That's not such a big deal.

Yah, but if I toss a piece of foam out the window driving at 100 miles an hour, and I'm driving a semi-truck, I bet that piece of foam is going to slow down quite a bit by the time it gets to the end of the trailer. (And the orbiter is about 1.5 semi lengths). Baseballs have a large mass compared to surface area, foam has a small mass compared to surface area. Point being that foam will slow down much faster than a baseball.

I still think your question is intereresting, I just don't think the armchair comparisons to a baseball dropped from a car are at all valid.

Re:happens often

[sowellfan]

Ok, I went & read the FAQ you linked to, but you have misinterpreted what it says. It says that the "Lightweight" tank was used on the Columbia. Regarding the "Superlightweight" tanks, it says,

"Since 1998, however, a revised tank model - a 'Superlightweight' tank - has been in use."

The same FAQ says in the next paragraph,

"In addition to the development of the 'Superlightweight' tanks, Lockheed also began using a reformulated lighter version of the inch-thick, spray-on insulation used on all external tanks in the mid-1990s. The switch was made to comply with an EPA mandate to limit ozone-depleting chemicals."

So the new foam came into use on *ALL* tanks (doesn't say 'only superlightweight'), starting in the mid-1990s, whereas the "superlightweight" tank only came into service in 1998.

The FAQ also says that the use of the new "Superlightweight" tank started with STS-91. But the same FAQ talks about the extensive tile damage found on the return to earth of STS-87, and it mentions that the new, 'environmentally-friendly' foaming method was used on STS-87. It also refers to this new foaming method being one of a few possible reasons for the extensive tile damage. STS-87 comes before STS-91 (unless they have some weird numbering system I don't know about), so it couldn't have used one of the new 'Superlightweight' tanks with its 'environmentally-friendly' foam. So it is apparent from this evidence also, that the new foaming method was used with the Columbia tanks.

If you are going to try to refute somebody, and then post a link to your supposed evidence, please read your evidence carefully so I don't have to waste my time responding.

Re:happens often

[jafac]

Yes. "Fair and Balanced" Faux news would have us blame the environmentalists for forcing NASA to use unsafe foam.

That makes all the sense in the world. Instead of blaming the engineers who made the decision to launch in the face of overwhelming evidence that:
a) Foam is falling off of the tanks (does not matter WHY)
b) Foam strikes are already shown to cause tile damage.
c) Ice strikes on Atlantis mission in 2000 caused enough tile damage to create a hot-gas breach on re-entry which was non-fatal. (but easily could have been).

These three points show that something was known about the problem and something should have been done. It doesn't matter WHY the foam fell off. It was known to be falling off. The problem was this decision-making process. Not the foam!