[brooklin]

All it had to do was knock off one tile.

[mewzilla]

I may be may mistaken, but one tile coming off wouldn't do it. I believe they've even landed with a few missing. But tiles off the leading edge of the wing would pose a far greater problem, I think. If that's what happened.

[GRRRRR]

"normally"...during the mission, up to several hundred tiles are damaged, chipped and so forth and need to be replaced before the next mission. Some tiles DO fall off during re-entry each mission with little to no effect. The tiles are made from expanded foamed Silcon Oxide (if I remember correctly) and are highly insulating. You have all seen the videos years ago, of a tile coming out of a furnace and being held by fingers on the corners of the tile, while the center of the tile glows cherry red...I suspect a structural failure or an explosion of the on board APU's that spin up as the shuttle enters the atmosphere. These APU's provide electrical power during re-entry...

Bless them...

[bonesmccoy]

The leading edge of the wing is REinforced Carbon Carbon...not tile.

[Rockitz]

All it had to do was knock off one tile.

Actually, a well placed tile might do it, but the shuttle typically loses some tiles during flight. If the tile were lost on one of the control surfaces (wings) and especially a leading edge of a wing then all bets are off. I'm sure the entire aerospace community will be doing CFD analyses for the next year in an effort to determine what kind of damage requires repair on-orbit for a safe reentry. Future flights will carry repair kits to fix such damage on-orbit.