Piasecki H-21

In the 1940s, the Pyasetsk Helicopter company developed several helicopters with a longitudinal propeller layout, the last of which was the H-21 ordered by the US Air Force in 1949 . The prototype XH-21 (internal designation Pyasetskiy Model 44 ) first flew April 11, 1952, the first production helicopter took off in October 1953.

Like the previous cars of the company, the H-21 for the characteristic shape of the fuselage received the nickname "flying banana." He was in service not only with the Air Force, but also with the US Army and Coast Guard . In total, 707 helicopters of this type were produced, of which 150 were exported.

On August 23-24, 1957, one H-21C performed the first non-stop transcontinental flight of a helicopter through the territory of the United States. The flight from San Diego to Washington lasted 31 hours 40 minutes and took place with four refueling ^[1] .

Helicopter longitudinal scheme .

Since the summer of 1956, the French H-21s were used in the Algerian War . They were mainly used to transport troops, although there was an unsuccessful attempt to turn the H-21 into a fire support helicopter. Typically, French cars were armed with a 12.7 mm machine gun or a 20 mm cannon mounted in the doors.

The H-21s were the first U.S. helicopters to fly to South Vietnam . In December 1961, two helicopter companies arrived in the country, immediately involved in the transfer of South Vietnamese troops. Combat use showed that the H-21 had insufficient maneuverability and survivability. However, at first the airmobile operations were successful, since the partisans of the NLFU were not familiar with the helicopters and the tactics of their use, and, accordingly, could not adequately counteract them. The "black day" for American helicopter pilots was January 2, 1963 , when during the battle of Ap-Buck four CH-21s were shot down and made an emergency landing. Gradually (since 1962), the Shaunis were replaced by the more modern Huey (UH-1), and by the time the US ground forces were brought into South Vietnam, the operation of the CH-21 was almost complete.

• XH-21 - designation of the Air Force for the first prototype.
• YH-21 - Air Force designation for 18 pre-production helicopters.
• H-21A "Work Horse" (since 1962 - CH-21A ) - the first production modification. Built 38 cars.
• H-21B (since 1962 - CH-21B ) - modification with a more powerful engine, autopilot and some other changes. 163 cars built.
• SH-21B (since 1962 - HH-21B ) - search and rescue option.
• H-21C "Shawnee" (since 1962 - CH-21C ) - the most massive modification for the US Army, built 334 cars.
• H-21D is the designation of two cars on which the T-58-GE gas turbine engines were installed.
• Model 42A - eight Royal Royal Canadian Air Force vehicles converted for civilian use. Could carry up to 19 passengers or up to 1279 kg of cargo (or 2268 kg on an external sling).
• Model 44A is a commercial version of the H-21B, designed to carry 19 passengers.
• Model 44B is a commercial version of the H-21B, designed to carry 15 passengers and additional cargo.
• Model 44C is a commercial version of the H-21B, designed to carry 8 passengers.
• HKP-1 - designation of vehicles in the Armed Forces of Sweden .

•   Canada (Air Force) - H-21A, Model 44A (years?)
•   France (Army) - H-21C (years?)
•   Germany (Air Force, Army) - H-21C (years?)
•   Sweden (Air Force, Navy) - under the designation HKP-1 (years?)

The data of the variant CH-21B are given.

• Crew: 2 people
• Rotor Diameter: 13.41 m
• Length: 26.31 m
• Fuselage Length: 16.03 m
• Height: 4.7 m
• Empty weight: 3629 kg
• Maximum take-off weight: 6668 kg
• Engine: PD Wright R-1820 -103 Cyclone (1063 l. From. )
• Maximum speed: 211 km / h
• Practical range: 644 km
• Practical ceiling: 2360 m
• Load:
  • 20 equipped soldiers or
  • 12 stretchers and 2 orderlies
• Armament: 7.62 mm or 12.7 mm machine gun in the doorway

• CH-21 Work Horse (Shawnee) on airwar.ru
• CH-21 Shawnee / Vertol 44 Helicopter at Boeing website