ke4roh's Journal: Historical Tile Damage

ET=external tank (the big orange thing)
SRB=solid rocket booster (the tall white rockets)

Atlantis sustained notable damage on STS-27 (the second flight after Challenger's explosion). They concluded it was from the right SRB nose cap which had an old-style surface. They also found ET foam and cork from SRB joints in the tile's pits. NASA made an interesting report in approving launch for STS-29.

In December, 1997, NASA was readying Endeavour for STS-89. They sanded the ET near the SRB joints, remarking, "While investigations into the cause of Columbia's unusual tile damage continue, managers hope the additional work will reduce the possibility of external tank foam debris contributing to Shuttle tile damage." One individual wrote about the damage.

Update: The Institute for Operations Research and the Management Sciences (INFORMS) has re-released a report commissioned by NASA about the risk to space shuttles from damage to the spacecraft's protective tiles.

Update: RISK MANAGEMENT FOR THE TILES OF THE SPACE SHUTTLE - 1994
STS-87 POST-FLIGHT INSPECTION - 1997