I think NASA knows exactly what went wrong wtih Columbia
after Thursday's experimental demonstration.
I don't want to brag, but I remember posting some mathematical
equations on this forum [a few months ago] showing that the impact-energy of the foam against the leftwing was equivalent to the explosive energy of an ounce [28 grams] of gunpowder; enough to do some
noticeable damage.
Actually, I underestimated the impact-energy back then [surprise surprise!]; the impact-energy was a magnitude greater than my calculations indicated....so it's obvious the impacting foam damaged the left-wing enough to doom Columbia.