Little-known American Rotary Wing Prototypes & Projects

[hesham]

From JAWA 1985,

here is a little known helicopter designed by Mr. Richard R. Degraw.

Another picture

 

[hesham]

From Aviation magazine 1965,

the Wigal autogiro.

From JAWA 1965-1966

 

[hesham]

Cobra Helicopter,not from Bell,

Redback Aviation - Cobra Helicopter History and Reference

 

[hesham]

From the site of my dear Stingray,

I don't know if this is American design or not ?,McK Aviation MK90,

The MK90 is the answer to cities congested congested by road traffic, to the need to be present in several places in a short period of time, to the desire to be in Capri for lunch.
It carries you and a companion rapidly and in comfort from where you are to where you want to go.
Enjoy flying in the superbly appointed interior of the MK90.
The MK90 is compact, facilitating take-off and landing in small places.
·The MK90 has excellent visibility and ample space, while maximizing aerodynamics.
·The MK90’s clean lines and push propeller enable a cruising speed of over 200km/h for nearly four hours.
·The MK90 combines push propeller with turbine effect to enable long hovering, even in hot weather.
·Co-axial rotors, single engine, 135hp
·Dual tandem seats.
·Small rotor diameter, while providing maximum lift and stability.
·The MK90 is a brilliant technical solution between an ultralight and a larger helicopter.

 

[hesham]

In the site of my dear Stingray,

From Walter:

2-seat light helicopter

one 360hp rotary engine (280hp Mazda 13-B?) driving a compressor
280hp: max. speed 90mph, cruise 70mph, ceiling 10,000ft, endurance 4 hours
rotor diameter 35.991ft; length 18.012ft; height 8ft

DETAILS: The Air Jet was a further development of the Eagle helicopter (qv) of Eagle Helicopter Corporation and American Air Jet. Inc was formed to continue development. It was a design of a team comprising Messrs. Stephen Willman, Russell Pitts, Michael Diekman, Raymond Berry. The Air Jet used the cold-cycle-pressure-jet principle (air from a compressor driven by the engine was channelled to exhaust nozzles at the tips of the rotor blades) and a prototype aircraft was completed in 1987 or 1988 and shown at the 1988 Sun-‘n Fun convention. Possibly only this prototype was built and it was maybe not flight tested, although first flights were also reported as having taken place in July 1988. The engine in the prototype was one 280hp rotary engine (360hp Mazda 13-B?).

Production: 1

American Air Jet, Inc. 710 Sunnywood Pl. Woodland Park, CO 80863