Three generations of American piston-engined combat aircraft share the sky at an air show flypast, 7 June 2014. The pair at center appear to be a North American P-51 Mustang leading a Douglas A-1 Skyraider; the aircraft at lower left is most likely a Republic P-47 Thunderbolt. Together they span the Second World War fighter force and the Vietnam-era attack mission, all built around the same fundamental technology - a big reciprocating engine turning a propeller. Photographed at an event associated with the Tennessee Museum of Aviation, Sevierville, from the Neal Melton material in the Don Engebretsen collection. Contemporary commemorative flying, not wartime imagery. Project: 219310