Pan Am Flight 214

Pan Am Flight 214 was a scheduled flight of Pan American World Airways from San Juan, Puerto Rico, to Baltimore, Maryland, and Philadelphia, Pennsylvania. On December 8, 1963, the Boeing 707 serving the flight crashed near Elkton, Maryland, while flying from Baltimore to Philadelphia, after being hit by lightning. All 81 occupants of the plane were killed. It was the first fatal accident on a Pan Am jet aircraft since the company had taken its first delivery of the type five years earlier.

An investigation by the Civil Aeronautics Board concluded that the cause of the crash was a lightning strike that had ignited fuel vapors in one of the aircraft's fuel tanks, causing an explosion that destroyed one of the wings. The exact way that the lightning had ignited the fumes was never determined. However, the investigation revealed various ways that lightning can damage aircraft in flight, which led to new safety regulations. The crash also led to research into the safety of different types of aviation fuel and research into methods of reducing dangerous fuel-tank vapors.

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