A Burned-Out Bulb and a Missing Strap Crashed New York's Air Traffic Control
One Manhattan power room took down FAA air traffic control in 1991
On September 17, 1991, a routine generator transfer at AT&T's windowless 33 Thomas Street hub tripped the rectifiers in its 20th-floor power room. Backup batteries masked the fault for over six hours, but a burned-out indicator lamp, a missing 25-inch jumper strap, a clamped alarm bell, and an unstaffed watch handoff kept anyone from noticing. When the batteries died at 4:40 p.m., radar and radio links to New York TRACON and three airports failed, disrupting 1,174 flights.
The alarm was clamped so that it was ringing lightly, but not loud enough to be audible.