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Lastly, I wonder how long this kind of thing has been going on, and it was just never either noticed or made public.


That part has a lot of people worried. Previously, we knew that the tiles got damaged and some were actually lost, but they just went with the flow because nothing happened before. Now, they are looking at the shuttle while in orbit at a level never experienced before. Its a case of 'if you look hard enough, you will find something wrong'. How much will they find that would put the shuttle at risk and how much is a normal occurance is a question we can't answer.

The lining between tiles was found sticking out before, but they never knew how long it was before re-entry (admittedly, a lot further back along the underside than the current protrusions). There is no data on how much the material is going to burn up. They are taking extra precautions now when we don't have the data on whether it will make the matter worse, better, or not affect it at all.

- Tim