The Arup S-4 (Model 104) is the last in a series of round-wing aircraft from

C.L. Snyder CL or cl may refer to: Arts and entertainment * CL (rapper) or Lee Chae-rin (born 1991), singer and rapper, former leader of the K-pop girl group 2NE1 * Creative Loafing, a newspaper publisher Brands and enterprises * Colgate-Palmolive's NYS ...

Design and development

The S-4 was engineered by Raoul Hoffman. The test pilot was Glenn Doolittle, a cousin of

Jimmy Doolittle James Harold Doolittle (December 14, 1896 – September 27, 1993) was an American military general and aviation pioneer who received the Medal of Honor for his daring raid on Japan during World War II. He also made early coast-to-coast flights ...

. The S-4 used a low aspect ratio, semi-circular planform wing with a

conventional landing gear Conventional landing gear, or tailwheel-type landing gear, is an aircraft undercarriage consisting of two main wheels forward of the center of gravity and a small wheel or skid to support the tail.Crane, Dale: ''Dictionary of Aeronautical Term ...

and a small rudder with attached elevator on the rear of the fuselage. The aircraft was entered through a door mounted on the bottom of the aircraft.

Operational history

The S-4 prototype flew extensively in promotional demonstrations. The S-4 was emblazoned with Sears Roebuck and Company logos. The aircraft was scrapped for war materials in

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposing ...

Variants

Hoffman Flying Wing Raoul J. Hoffman was a Hungary-born hebrew engineer who moved to the United States of America and is notable for the aircraft he designed or helped to design. Aircraft design Hoffman helped develop the Laird Super Solution racer, and Owl Trimotot ...

a design based on the Arup S-4 aircraft. *

Milt Hatfield Little Bird The Hatfield Little Bird aircraft are a continuation of the Arup series of low aspect ratio aircraft. Development In the late 1920s, Cloyd Snyder of South Bend, Indiana developed a series of "Heel Lift" low aspect ratio aircraft inspired by the ...

- similar design.

Aircraft on display

A replica is on display in the atrium of South Bend Airport

Specifications (S-4)

References

{{reflist 1930s United States experimental aircraft Single-engined tractor aircraft Aircraft first flown in 1935 Mid-wing aircraft