I sort of forgot about this when I heard about it right after 9-11. (via Eschaton)
The fire and smoke from the downed passenger aircraft billows from the Pentagon courtyard. The Pentagon was a model and the “plane crash” was a simulated one. The Pentagon Mass Casualty Exercise was just one of several scenarios that emergency response teams were exposed to Oct. 24-26 in the Office of the Secretaries of Defense conference room.
So much for ‘no one every thought someone would hijack planes and fly them into buildings.