McDonnell XH 20 Little Henry

Development

The McDonnell Model 38 was a lightweight experimental helicopter sponsored by the United States Army Air Force to test the concept of using small ramjets at the tips of the rotor blades. As a functional helicopter it was of simple open-frame steel-tube construction. Allocated the military designation XH-20 the first of two first flew on the 29 August 1947.

Although the XH-20 flew successfully the ramjets were noisy and burnt a large amount of fuel and plans to build a larger two-seat XH-29 were abandoned.

Variants

XH-20

McDonnell Model 38 experimental lightweight helicopter, two built.

XH-29

McDonnell Model 79 a proposed two-seat development, cancelled.

Operator

 United States

United States Air Force

Aircraft on display

46-689 the first XH-20 is on display at the National Museum of the United States Air Force

Specifications

Data from

General characteristics

Crew: 1

Length: 12 ft 6 in (3.81 m)

Height: 6 ft 8 in (2.03 m)

Empty weight: 290 lb (132 kg)

Powerplant: 2 × McDonnell Ramjets

Main rotor diameter: 20 ft (6.1 m)

Performance

Maximum speed: 50 mph (80 km/h; 43 kn)