Back Kellett XR-8

Kellett XR-8

This experimental military two-seater helicopter, which first flew on 7th August 1944, differed radically from earlier Kellett designs and was nicknamed "Synchropter" because of its two intermeshing three-bladed rotors.

This configuration, familiarly known as "egg-beater" and used in 1938 by the German designer Flettner for his Fl.265, first appeared in the United States on this helicopter with blades which overlapped as the rotors turned in opposite directions.

The distance between the XR-8's two hubs was 1.22 metres, and power was directly transmitted to the rotors through pairs of bevel gears.

P.Lambermont "Helicopters and Autogyros of the World", 1958

Kellett XR-8

Technical data for Kellett XR-8

Number of seats: 2, engine: 1 x Franklin O-405-9 rated 245hp, rotor diameter: 10.97m, overall length: 6.89m, height: 3.36m, weight fully loaded: 1347kg, empty weight: 1052kg, cruising speed: 136km/h, maximum speed: 160km/h, absolute ceiling: 2050m

Kellett XR-8

Kellett XR-8

Kellett XR-8

Joe May, e-mail, 04.05.2023reply

Are there any scale drawings of this helo?

James Malcolm Lindgren, e-mail, 27.03.2024 Joe May

I am working on this aircraft in the restoration hangar at The Museum of the USAF in Dayton Ohio
, We have no plans or drawings for thismachine,


Larry Phillips, e-mail, 16.12.2009reply

I would like to know about this aircraft

James Malcolm Lindgren, e-mail, 27.03.2024 Larry Phillips

I am currently working on this aircraft in restoration at the Airforce Museum in Dayton Ohio,


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