9:53 a.m. September 11, 2001: Emergency Transmitter Goes Off, Indicating a Plane Crash in Michigan

A radio transmitter carried by aircraft that is designed to go off automatically if a plane crashes is activated in the vicinity of the city of Ann Arbor in southeast Michigan, although the distress signal is presumably a false alarm. Details of the distress signal will be described when an unidentified individual calls the FAA’s Cleveland Center at around 10:19 a.m. and tells an air traffic controller there, “I’ve got an ELT reported over Ann Arbor.” [Federal Aviation Administration, 9/11/2001; Federal Aviation Administration, 10/14/2003] 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 efforts in locating the downed aircraft. [Federal Aviation Administration, 3/23/1990; Federal Aviation Administration, 7/12/2001; Aircraft Owners and Pilots Association, 1/22/2009] The caller will not say who reported the ELT signal to him. But he will say the signal “started at 13:53” Zulu time, which is 9:53 a.m. Eastern time. Presumably realizing the signal was therefore activated over 25 minutes earlier, the caller will add, “Wait a minute, that don’t make any sense.” But the Cleveland Center controller will tell him: “Yeah, it does. It might have been late to be…” The caller will then say, “Okay, well I’ve got an ELT reported over Ann Arbor,” before the call ends. [Federal Aviation Administration, 9/11/2001] Further details of the ELT signal and what might have caused it are unknown. Flight 93 will crash in rural Pennsylvania about 10 minutes after the signal over Ann Arbor is activated (see (10:03 a.m.-10:10 a.m.) September 11, 2001 and (10:06 a.m.) September 11, 2001). [9/11 Commission, 7/24/2004, pp. 30] However, apparently no ELT signal will go off when it crashes (see 10:07 a.m. September 11, 2001). [Federal Aviation Administration, 9/11/2001] According to Major Allan Knox, who works at the Air Force Rescue Coordination Center at Langley Air Force Base in Virginia, most ELT signals are false alarms. [9/11 Commission, 10/6/2003 ]