Arup S-4
The Arup S-4 is the last in a series of round-wing aircraft from C.L. Snyder.The S-4 was engineered by Raoul Hoffman. The test pilot was Glenn Doolittle, a cousin of Jimmy Doolittle.
The S-4 used a low aspect ratio, circular planform wing with a conventional landing gear 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.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.Variants
A replica is on display in the atrium of South Bend AirportSpecifications (S-4)
