Thermal tiles are fragile, you can transverse it with a pencil.  They
should be protected all the way until reentry. They are not necessary
anyway until the shuttle returns and hit atmosphere at high speed.  Even a
thin metal foil all the way over the tiles would avoid the problem.  Let it
burn upon reentry, or just discard it in space before reentry.

It is amazing to think that even a 3 lbs bird flying at 2000ft can damage
seriously the tiles and plant a big risk at the reentry.  The shuttle
lift-off speed at 2000ft crash with the bird would be enough to damage
several tiles.

Based on the actual jokes around, perhaps some yards of Duct-Tape could
hold the external tank foam in place...

Wagner.

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