Swissair Flight 111 (SR111, SWR111) was a Swissair McDonnell Douglas MD-11 on a scheduled airline flight from John F. Kennedy International Airport in New York City, United States to Cointrin International Airport in Geneva, Switzerland. This flight was also a codeshare flight with Delta Air Lines.
On Wednesday, 2 September 1998, the aircraft used for the flight, registered HB-IWF, 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 (5.0 mi) from shore, roughly equidistant from the tiny fishing and tourist communities of Peggys Cove and Bayswater. All 229 people on board died—the highest death toll of any aviation accident involving a McDonnell Douglas MD-11 and the second-highest of any air disaster to occur in Canada, after Arrow Air Flight 1285. This is one of only three hull losses of the passenger configured MD-11, along with China Airlines Flight 642 and China Eastern Airlines Flight 583 .
The initial search and rescue response, crash recovery operation, and resulting investigation by the Government of Canada took over four years and cost CAD 57 million (at that time approximately US$38 million). The Transportation Safety Board of Canada's (TSB) official report of their investigation stated that flammable material used in the aircraft's structure allowed a fire to spread beyond the control of the crew, resulting in a loss of control and the crash of the aircraft.
Swissair Flight 111 was known as the "UN shuttle" due to its popularity with United Nations officials; the flight often carried business executives, scientists, and researchers.