The U. S. Army selected the Sikorsky Choctaw in 1955 as a medium lift cargo and troop transport. Built as the CH-34A between 1955 and February of 1959 there were 426 Choctaws delivered to the Army. Others were delivered to the United States Air Force and Navy. Beginning in 1958 the Choctaw was upgraded to CH-34C standards with the installation of auto-stabilization systems to allow all-weather operations. Also beginning in 1958 several Choctaws were converted to VIP transports for use by the Executive Flight Detachment and provided helicopter transport for the President until the end of 1964
This Seabat was taken on charge by the Royal Netherlands Navy on 26 Jun 1963. It was withdrawn from use 28 Jun 1972 and became an instructional airframe in Aug 1973. Later transferred to the Militaire Luchtvaart Museum.
Originally an anti-submarine warfare HSS-1. Converted to UH-34G and transferred to South Vietnamese Air Force in 1967. Later N586HS. 'RP' on the fuselage appears to be an individual aircraft code; 'DM' is painted on the nose.