As for the actual day of September 11, 2001, the commission report says of NORAD's radar tracking abilities for flights originating within the United States:
F-15 fighters were scrambled at 8:46 from Otis Air Force Base. But NEADS did not know where to send the alert fighter aircraft, and the officer directing the fighters pressed for more information: "I don't know where I'm scrambling these guys to. I need a direction, a destination." Because the hijackers had turned off the plane's transponder, NEADS personnel spent the next minutes searching their radar scopes for the primary radar return. American 11 struck the North Tower at 8:46. Shortly after 8:50, while NEADS personnel were still trying to locate the flight, word reached them that a plane had hit the World Trade Center.6
Controllers at NEADS located an unknown primary radar track [Flight 77], but "it kind of faded" over Washington. The time was 9:38.The Pentagon had been struck by American 77 at 9:37:46.The Langley fighters were about 150 miles away.7
NEADS first received a call about United 93 from the military liaison at Cleveland Center at 10:07. Unaware that the aircraft had already crashed [at 10:03], Cleveland passed to NEADS the aircraft's last known latitude and longitude. NEADS was never able to locate United 93 on radar because it was already in the ground.8
NEADS never lost track of Delta 1989, and even ordered fighter aircraft from Ohio and Michigan to intercept it.9
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