You're right. A little more googling http://en.wikipedia.org/wiki/Space_Shuttle_external_tank http://en.wikipedia.org/wiki/Space_Shuttle_external_tank reveals t

You're right. A little more googling http://en.wikipedia.org/wiki/Space_Shuttle_external_tank http://en.wikipedia.org/wiki/Space_Shuttle_external_tank reveals the old foam began to be phased-out in 1996, with complete phase-out in 1997. Tile loss and other damage starting even with the first flight were assumed to be related to foam loss, and the foam loss itself was determined/assumed to be due to anomalies in foam application.