both occupants of the Swift were killed but the DC-6 landed safely. February 14, 1953 National Airlines Flight 470 crashed in the Gulf of Mexico 20 mi SE off Mobile Point, Alabama after it broke up in severe turbulence from a thunderstorm, killing all 46 passengers and crew on board; the aircraft possibly flew into a waterspout. April 20, 1953 Western Air Lines Flight 636 (a DC-6B, N91303) crashed in San Francisco Bay due to pilot error, killing eight of 10 on board. July 12, 1953 Transocean Air Lines Flight 512 crashed in the Pacific Ocean 344 miles east of Wake Island for reasons unknown, killing all 58 passengers and crew on board. October 29, 1953 British Commonwealth Pacific Airlines Flight 304 from Sydney, Nadi (Fiji), Canton Island, and Honolulu crashed in the Santa Cruz Mountains seven miles (11 km) southeast of Half Moon Bay, California, while preparing to land at San Francisco Airport; all 19 on board were killed, including American pianist William Kapell, age 31, who was returning to the United States following a three-month concert tour in Australia. January 14, 1954 A Philippine Airlines DC-6 (PI-C294) crashed near Rome due to a loss of control caused by possible turbulence, killing all 16 passengers and crew on board. August 23, 1954 KLM Flight 608, a DC-6B (PH-DFO, Willem Bontekoe), crashed in the North Sea 37 km north of the Dutch coast, killing all 21 passengers and crew on board; the cause was not determined, but cockpit window failure, autopilot failure, an in-flight explosion or an overheating electrical system were suspected. December 18, 1954 Linee Aeree Italiane Flight 451 (a DC-6B, I-LINE) crashed while attempting to land at Idlewild Airport (now John F. Kennedy International Airport) due to pilot error and fatigue, killing 26 of 32 on board. February 13, 1955 Sabena Flight 503, a Douglas DC-6 (OO-SDB), crashed on Monte Terminillo, near Rieti, Italy; all 29 on board died, including actress and 1953 Miss Italia winner Marcella Mariani. March 22, 1955 US Navy R6D-1 Liftmaster 131612 crashed into Pali Kea Peak in the Waianae Range near Honolulu, Territory of Hawaii, after the crew made a navigational error, killing all 66 people on board. April 4, 1955 A United Airlines DC-6 crashed at MacArthur Airport during a training flight due to pilot error, killing the three crew. November 1, 1955 A time bomb exploded aboard United Airlines Flight 629,