The McDonnell XHJH Whirlaway, aka McDonnell Model 65, was a 1940s American experimental transverse-rotor helicopter designed and built by McDonnell Aircraft Corporation for the United States Navy and was the largest helicopter at the time, as well as the first successful twin-engined twin-rotor helicopter in the world.

Design and development

In 1944, the United States Navy issued a requirement for a large rescue helicopter with capacity for ten occupants. The design was originally designated XHJD-1; shortly after flying it was re-designated the XHJH-1. It was derived from the single-engined, twin rotor

Platt-LePage XR-1 The Platt-LePage XR-1, also known by the company designation PL-3,Francillon 1990, p.49. was an early American transverse rotors helicopter, built by the Platt-LePage Aircraft Company of Eddystone, Pennsylvania. The winner of a United Stat ...

. James McDonnell had invested in that company in 1942 and some of his engineers had been working there, gaining experience of helicopter design and production techniques. McDonnell took control of the company in June 1944. The XHJH-1 first flew two months later. It had twin side-by-side rotors at the end of pylon wings which turned in opposite directions. Each rotor was powered by a

Pratt & Whitney R-985-AN-14B Wasp Junior The Pratt & Whitney R-985 Wasp Junior is a series of nine-cylinder, air-cooled, radial aircraft engines built by the Pratt & Whitney Aircraft Company from the 1930s to the 1950s. These engines have a displacement of ; initial versions produced , ...

engine.

Variants

;XHJD-1 :Original United States Navy designation. ;XHJH-1 :Designation changed before first flight.

Aircraft on display

The sole XHJH-1 is held by the

National Air and Space Museum The National Air and Space Museum of the Smithsonian Institution, also called the Air and Space Museum, is a museum in Washington, D.C., in the United States. Established in 1946 as the National Air Museum, it opened its main building on the Nat ...

Specifications

References

External links