8:58 a.m. September 11, 2001: Emergency Transmitter Goes Off, Signaling a Plane Crash, Minutes before Flight 175 Hits WTC

A special radio transmitter that is carried by aircraft and designed to go off automatically if a plane crashes is activated in the New York area, several minutes before Flight 175 hits the World Trade Center. David Bottiglia, an air traffic controller at the FAA’s New York Center, receives information from one of the aircraft he is monitoring. A few seconds before 8:59 a.m., the pilot of US Airways Flight 583 tells him, “I hate to keep burdening you with this stuff, but now we’re picking up another ELT on 21.5.” [Federal Aviation Administration, 9/11/2001, pp. 37 ; 9/11 Commission, 10/1/2003 ; 9/11 Commission, 2004] An “ELT” is an emergency locator transmitter, a device carried on most general aviation aircraft in the US that is designed to automatically begin transmitting a distress signal if a plane should crash, so as to help search and rescue attempts at locating the downed aircraft. [Federal Aviation Administration, 3/23/1990; US Department of the Army, 8/12/2008, pp. E-6 ; Aircraft Owners and Pilots Association, 1/22/2009] “21.5” refers to the emergency frequency of 121.5 megahertz that ELTs transmit their distress signals on. [Aircraft Electronics Association, 2009, pp. 36 ] While the pilot’s information would mean an ELT is activated at around 8:58 a.m., Flight 175 will crash into the WTC several minutes later, at 9:03 a.m. and 11 seconds (see 9:03 a.m. September 11, 2001). [9/11 Commission, 7/24/2004, pp. 8] And yet there are no reports of an ELT going off at the time of the crash itself. The pilot of Flight 583 earlier on informed Bottiglia of another ELT signal, which had been transmitted shortly before Flight 11 hit the WTC (see 8:44 a.m. September 11, 2001). [New York Times, 10/16/2001; 9/11 Commission, 10/1/2003 ]