Piasecki H-21 Shawnee
The Piasecki H-21 Shawnee, called the Workhorse in Air Force service, was a tandem-rotor transport helicopter built by Piasecki Helicopter Corporation. First flown in April 1952, it was produced in 707 examples, 150 of them for foreign services, and flew with the United States, Canadian, French, West German, Swedish and Japanese forces. Designed as an Arctic rescue helicopter, it became a troop transport that pioneered air-assault tactics in Algeria and was among the first American helicopters deployed to Vietnam, where it served as the Army's main helicopter until 1964.
Why It Mattered
The H-21 was the fourth tandem-rotor helicopter design from Piasecki, and the first of the line to reach large-scale production: Piasecki Aircraft Corporation's own accounting puts the total at 707 aircraft, 150 of them for foreign services in West Germany, Canada, France, Sweden, Japan and other countries. French H-21s in Algeria pioneered troop air-assault tactics, and in December 1961 the Army's Shawnee was among the first American helicopters deployed to Vietnam, where it stayed the Army's main helicopter until 1964. Its career linked two eras of military flying: Arctic rescue work in the 1950s and the helicopter war that opened in Vietnam.
Design Notes
The H-21 kept the tandem layout of Piasecki's earlier HRP series, with two three-bladed rotors turning in opposite directions at the ends of the fuselage. The rear fuselage angled upward, a shape inherited from the HRP-1 that kept the large rotors from striking the airframe and gave the family its "flying banana" nickname. The H-21 was an all-metal derivative of the HRP-1. One Wright R-1820 Cyclone radial drove both rotors: 1,150 horsepower in the first aircraft, raised to 1,425 horsepower in the H-21B and the versions that followed. Designed for Arctic rescue, the type was winterized to work at temperatures down to −65 °F and could be fitted with wheels, skis or floats. As a transport it carried 22 fully equipped troops, or 12 stretchers with two medical attendants.
Operational History
The YH-21 first flew on 11 April 1952, and the Air Force ordered two production versions: 32 H-21A search-and-rescue aircraft and 163 H-21Bs, a more powerful transport variant. In American and Royal Canadian Air Force service the type supplied the Distant Early Warning radar stations across the Arctic, from the Aleutian Islands and Alaska to Greenland and Iceland. France took the H-21C to Algeria, where troop-carrying aircraft worked alongside H-34s in large counterinsurgency operations; experiments with fixed rockets and machine guns gave way to flexible door guns for defense when landing troops under fire. The Army's version, renamed CH-21 in 1962, reached South Vietnam in December 1961 with the 8th and 57th Transportation Companies, in support of South Vietnamese forces. There the cold-weather design struggled: it could lift only nine of its 20 passengers in the heat, engines lasted a fraction of their rated life, and unprotected control cables and fuel lines left it open to ground fire. The shooting down of a Shawnee near the Laotian border in July 1962, with the loss of four aviators, was among the Army's earliest casualties of the war. The type nevertheless remained the Army's main helicopter in Vietnam until the UH-1 replaced it in June 1964; the CH-47 followed in 1965, and later that year most CH-21s left American service.
Afterlife
Retirement began in 1964, and most H-21s had left service by the end of 1965; the retired aircraft went into storage at Davis-Monthan Air Force Base in Arizona, the yard known as the Boneyard. A commercial derivative, the Model 44, flew airline service with New York Airways. The type survives in museums in several countries, and one CH-21B in California is still flown, described in Wikipedia's survey of survivors as the last H-21 still flying. In Tucson, the Pima Air & Space Museum displays CH-21C 56-2159 wearing the markings of the 93rd Transportation Company, South Vietnam, 1962.