Swissair Flight 111

Information
Swissair Flight 111 was a flight from John F. Kennedy International Airport in New York City to Cointrin International Airport in Geneva. This flight was also a codeshare flight with Delta Air Lines. On 2 September 1998, the McDonnell Douglas MD-11 performing this flight crashed into the Atlantic Ocean southwest of Halifax International Airport at the entrance to St. Margarets Bay, Nova Scotia. The crash site was 8 kilometres (5 mi; 4 nmi) from shore, roughly equidistant from the tiny fishing and tourist communities of Peggy's Cove and Bayswater. All 229 passengers and crew on board the MD-11 were killed, making the crash the deadliest McDonnell Douglas MD-11 accident in aviation history.

Pilots
The captain was 50-year-old Urs Zimmermann. At the time of the accident, he had approximately 10,800 hours of total flying time, of which 900 hours were in an MD-11. He was also an instructor pilot for the MD-11. Before his career with Swissair, he was a fighter pilot in the Swiss Air Force. Zimmermann was described as a friendly person with professional skills, who always worked with exactness and precision. The first officer, 36-year-old Stefan Löw, had approximately 4,800 hours of total flying time, including 230 hours on the MD-11. He was an instructor on the MD-80 and A320. From 1982 to 1990, he had been a pilot in the Swiss Air Force. The cabin crew comprised a maître de cabine (purser) and eleven flight attendants. All crew members on board Swissair Flight 111 were qualified, certified, and trained in accordance with Swiss regulations under the Joint Aviation Authorities (JAA).

Background
The flight took off from New York's John F. Kennedy International Airport at 20:18 EDT (00:18 UTC) on 2 September. From 20:33 – 20:47 EDT (00:33 to 00:47 UTC), the aircraft experienced a radio blackout for approximately thirteen minutes, which was later found to be caused by communication radio tuning errors.

At 21:10 (01:10 UTC, 52 minutes after takeoff), the flight crew detected an odor in the cockpit and determined it to be smoke from the air conditioning system. Four minutes later, the odor returned and smoke became visible, prompting the pilots to make a "pan-pan" radio call to Moncton air traffic control, the area control center (ACC) station in charge of air traffic over the Canadian province of Nova Scotia. The pan-pan call indicated that there was an urgency due to smoke in the cockpit but did not declare an emergency as denoted by a "Mayday" call. The crew requested a diversion to Logan International Airport in Boston (234 nautical miles (433 km; 269 mi) away) before accepting Moncton ATC's offer of radar vectors to the closer Halifax International Airport in Enfield, Nova Scotia, 66 nautical miles (122 km; 76 mi) away. At 21:18 (01:18 UTC), Moncton Centre handed over traffic control of the plane to Halifax terminal air traffic control, the ATC station in charge of controlling traffic in and out of Halifax International Airport. Upon being advised by Halifax ATC that they were 30 nautical miles (56 km) from the airport, the crew requested more flight distance to allow the aircraft to descend safely from its altitude of 21,000 feet (6,400 m) at the time. The crew then requested to dump fuel to reduce their weight for landing. Halifax thus vectored the plane south toward St. Margaret's Bay where it was safe for the aircraft to dump fuel while remaining within 40 nautical miles of the airport. In accordance with the Swissair checklist 'In case of smoke of unknown origin', the crew shut off power to the cabin, which also turned off the recirculating fans in the cabin's ceiling. This allowed the fire to spread to the cockpit, eventually shutting off power to the aircraft's autopilot. At 21:24:28 AT (01:24:28 UTC), the crew informed Halifax that they now must fly manually, followed by declaring an emergency. Ten seconds later, the crew declared an emergency again, saying "...and we are declaring emergency now, Swissair one eleven"; this was the last transmission received from Flight 111. The aircraft flight data recorder stopped operating at 21:25:40 AT (01:25:40 UTC), followed one second later by the cockpit voice recorder. The aircraft's transponder briefly resumed transmission of secondary radar returns from 21:25:50 – 21:26:04 AT (01:25:50 to 01:26:04 UTC), at which time the aircraft's altitude was 9,700 feet. After this, the aircraft could only be tracked through primary radar, which does not provide altitude information.

At 21:31:18 AT (01:31:18 UTC), the aircraft struck the ocean at an estimated speed of 345 miles per hour (555 km/h; 154 m/s; 300 kn). The plane disintegrated instantly.