The following is a timeline of the NORAD response to the hijackings on 9/11, as based on the transcripts from over 30 hours of recordings inside the NORAD command centre.
All times are in Eastern Daylight Time
AA11 departs Logan International Airport
AA11 is hijacked. Short after its transponder is turned off
UA175 departs Logan International Airport
AA77 departs Washington Dulles International Airport
AA11 turns off its IFF (Identify Friend-or-Foe) beacon and begins deviating from its scheduled flight path
AA11 makes a 100 degree turn and heads for New York City
Boston Centre notifies NEADS of the hijacking of AA11 and requests an aircraft scramble. This is the first incident of the morning.
The two F-15s on alert status at Otis ANGB (Air National Guard Base) are put on “Battle Stations” (pilots enter their aircraft and await the signal to launch)
NEADS contact Boston Centre and discover they do not know where AA11 is (because the aircraft’s transponder has been turned off).
UA93 departs Newark International Airport
UA 175 is hijacked
Despite having no coordinates for intercept, NEADS decide to launch the Otis aircraft anyway.
AA11 hits the North Tower of the World Trade Centre
The stoplight at the Alert Barn on Otis ANGB turns from red to green, and the two F-15s taxi out to the runway.
Boston Centre notifies NEADS that an aircraft has flown into the WTC. NEADS immediately call New York Centre, and discover they do not yet know about the incident. This is the second aircraft incident of the morning (NEADS do not know it is AA11).
UA175 turns off course and fails to respond to communication. New York Centre knows the aircraft has been hijacked.
NEADS decide to direct the Otis fighters to New York City anyway.
AA77 is hijacked and its transponder is turned off. Indianapolis Centre loses contact with the aircraft and assumes it has crashed.
Confusion begins to arise as to whether the aircraft that hit the WTC was AA11. Confirmation is required from the airline company (who independently track their aircraft), however American Airlines does not confirm the fate of AA11. Airlines routinely go into “information lockdown” when a crisis occurs.
Indianapolis Centre notify the FAA that AA77 has been hijacked (realizing it did not crash).
NEADS are notified of a second hijacking. (3rd incident of the morning).
UA175 hits the South Tower of the WTC. A number of NEADS personnel witness it live on CNN.
FAA civilian controllers direct the Otis fighters to enter a holding pattern over Long Island. They are worried about the fighters colliding with civilian aircraft in the densely packed airspace over New York.
NEADS weapon controllers are not happy.
NEADS weapons controllers request the launch of the two F-16 fighters at Alert on Langley AFB (Air Force Base) in Virginia. However this request is refused by NEADS command. Instead the fighters are put on Battle Stations. NEADS command are concerned that the Langley fighters are the only remaining aircraft they have – if both pairs are airborne at the same time both pairs will run out of fuel at the same time.
Boston Centre notify NEADS of a third hijacked aircraft, headed for Washington DC. (4th incident of the morning).
Boston Centre overhears a FAA conversation which mentions AA11 is still airborne. Based on this and AA11’s previous known heading they determine that it is headed for Washington DC. They notify NEADS.
The Langley fighters are scrambled, however the pilots are not given a reason for a scramble. The Navy ATC handling them directs them east, over the Atlantic Ocean, to a military training airspace called Whiskey 386.
UA93 is hijacked.
In the course of a call to Washington Centre, NEADS finds out about the hijacking of AA77 (bringing the day’s total – from NEADS’ point of view – to 4 hijackings (one crashed into WTC) plus the first crash into the WTC as a 5th aircraft).
NEADS notice the F-16s are headed in the wrong direction, and contact the Navy ATC.
Boston Centre notify NEADS of yet another unidentified aircraft flying over Washington DC (6th aircraft incident).
The Langley Fighters are directed to head for the White House.
AA77 hits The Pentagon. The Langley Fighters are 150 miles away.
After several transmissions from the hijackers, Cleveland Centre is now aware that UA93 has been hijacked. However they do not notify the military – standard procedure in the event of a hijacking is to hand control over to the FBI.
Boston Centre notify NEADS of a possibly hijacking of Delta 1989. Unknown to Boston Centre, an ATC in Cleveland has already made contact with the crew of Delta 1989 and determined that there is no hijacking. This is the 7th aircraft incident of the day, as far as NEADS are aware.
NEADS begin contacting ANG bases along the aircraft’s path, as there are no NORAD aircraft in a position to intercept.
A base in Selfridge, Michigan offers up fighters to intercept Delta 1989.
Some time between 0954 and 1007, NEADS receive a call from NORAD Canada Region, notifying them of a suspected hijack aircraft headed south across the border to Washington. This is the 8th aircraft incident.
UA93 crashes into a field near Shankesville, Pennsylvania after passengers attempt to seize control of the cockpit.
Baltimore Centre becomes aware of an aircraft over the White House. 9th aircraft incident.
Cleveland Centre notifies NEADS of the hijacking of UA93 – unaware that it has already crashed. 10th aircraft incident.
The chase towards the White House continues, eventually ending when NEADS realize the unidentified aircraft spotted by Baltimore Centre is actually the two Langley F-16s.
NEADS are notified that UA93 has crashed.
30 seconds after being notified that UA93 has crashed, NORAD South East Air Defense Sector (SEADS) notifies NEADS of another potential hijacking. This is the 11th incident of the day.
False reports of hijackings, and real responses, continue well into the afternoon, though civilian air-traffic controllers had managed to clear the skies of all commercial and private aircraft by just after 12 p.m. The fighter pilots over New York and D.C. (and later Boston and Chicago) would spend hours darting around their respective skylines intercepting hundreds of aircraft they deemed suspicious. Meanwhile, Arnold, Marr, and Nasypany were launching as many additional fighters as they could, placing some 300 armed jets in protective orbits over every major American city by the following morning. No one at NEADS would go home until late on the night of the 11th, and then only for a few hours of sleep.
Primary Timeline Resources
Vanity Fair article “9/11 Live: The NORAD Tapes”
Information on AA 11
Information on UA 175
Information on AA 77
Information on UA 93
It is interesting to note that between 0837 and 1015 (98 minutes) NEADS are notified of 11 different incidents involving commercial aircraft (many of these turn out to be double-ups, phantom aircraft, mistakes, etc...)
I also have a word document version of this timeline.