[NittanyLion]

As I now understand it, the piece of "foam" that peeled off and struck the left wing during the launch phase was the size of a fairly large suitcase and as hard as a brick. Now............does anyone here know what speed the launch vehicle would have attained at 80 seconds into flight? I'm betting.........pretty damned fast. Take something that large and as hard as a brick......slam it into ceramic tiling at that speed..........and you have damage, folks. Severe damage.

You can only take into account the variance in velocities of the shuttle and foam - not the shuttle speed itself. We're more likely talking about a hundred MPH or so...

Also, the foam struck a glancing blow, so less energy would have been absorbed by the impact area.

[DoughtyOne]

FYI: I've read reports on the forum based on Dittemore's comments that NASA was assuming a 512 mph impact, but that they were doing this as a result of doubling the estimates in order to make sure tests were run at the optimal rather than the minimal chance for damage. This would indicate they're fairly confident the debris was going at least 256 mph.

[Capitalist Eric]

You can only take into account the variance in velocities of the shuttle and foam - not the shuttle speed itself. We're more likely talking about a hundred MPH or so...

Sorry, but you're wrong.

The foam possesses a low relative density, therefore having a very high surface area compared to weight. The laminar boundary layer- the "layer" of air right on the skin of the tank, which tends to move slowly, is a very thin layer- in this case, with the speeds we're discussing (~1,900 MPH was the last NASA estimate I heard about Shuttle speed at time of foam separation), it was probably a few molecules thick. So, as soon as the insulation broke loose, it was immediately decelerating. Considering the high surface area to mass ratio, the delta-V would have been very high... Imagine following a garbage truck driving down the highway at 60MPH, and a piece of styrofoam flies up out of the front of the garbage bin... By the time It's a few feet above the truck (and out of the turbulent air from the truck) it's ground speed is zero. I've watched this, before... What you see from the side, is that the foam pops straight up, is stopped in place by the wind, and the truck rolls out from under the foam...

At 1,900 MPH, and a distance of what... 50-75 feet???

Oh, yeah, there was a significant difference in speeds, by the time the foam hit the wing...

If the foam happened to be relatively hard, then regardless of whether it was a direct blow or a glancing blow, it is likely that tile damage would result...

CE