McDonnell XHJH Whirlaway

The McDonnell XHJH Whirlaway was a 1940s American experimental twin-rotor helicopter designed and built by McDonnell Aircraft for the United States Navy. It was the first successful twin-engined, twin rotor helicopter in the world. The Whirlaway was the largest helicopter flown up to that time.

Design and development
In 1944, the United States Navy issued a requirement for a large rescue helicopter with a capacity for ten occupants. The design was originally designated XHJD-1; shortly after flying it was re-designated the XHJH-1. The XHJH-1 first flew in August 1944, and had twin side-by-side 46 ft rotors at the end of pylon wings which turned in opposite directions. Each rotor was powered by a 450 hp Pratt & Whitney R-985 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.