On January 13, 1982, Air Florida Flight 90, a Boeing 737-222, was a scheduled flight to Fort Lauderdale, Florida, from Washington National Airport, Washington, D.C. There were 74 passengers and 5 crewmembers on board. The flight was delayed about 1 hour 45 minutes due to a moderate to heavy snowfall. Shortly after takeoff the aircraft crashed at 1601 e.s.t. into the 14th Street Bridge over the Potomac River and plunged into the ice-covered river, 0.75 nmi from the departure end of runway 36. Four passengers and one crewmember survived the crash. Four persons in the vehicles on the bridge were killed; four were injured. The National Transportation Safety Board determines that the probable cause of this accident was the flightcrew's failure to use engine anti-ice during ground operation and takeoff, and to take off with snow/ice on the airfoil surfaces of the aircraft. Contributing to the accident were the ground delay between de-icing and takeoff clearance.