Re: Enough! Time to put some numbers to conjecture: regarding Columbia.
If the foam hit the nomex filler between the leading edge and main wing, it could produce a breach. Over this seal is a structure which uses 4 bolts to hold on the carbon composite.
Another point at which failure due to foam impact could occur is in the landing gear door seals - but the AF photo shows leading edge damage.
Unfortunately, most likely what hit was not foam, but ice - the 500 pound safe. But we will see...
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