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."