The Arup S-4 (Model 104) is the last in a series of round-wing aircraft from C.L. Snyder.[1]
Design and development
The S-4 was engineered by Raoul Hoffman. The test pilot was Glenn Doolittle, a cousin of Jimmy Doolittle.[2]
The S-4 used a low aspect ratio, semi-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.[3][4]
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.[5]
Variants
- Hoffman Flying Wing a design based on the Arup S-4 aircraft.[6]
- Milt Hatfield Little Bird – similar design.[7]
Aircraft on display
A replica is on display in the atrium of South Bend International Airport[8]
Specifications (S-4)
Data from Janes, Popular Aviation
General characteristics
- Capacity: 2
- Length: 18 ft 6 in (5.64 m)
- Wingspan: 22 ft (6.7 m)
- Wing area: 273 sq ft (25.4 m2)
- Airfoil: NACA M-6
- Empty weight: 650 lb (295 kg)
- Gross weight: 1,200 lb (544 kg)
- Fuel capacity: 18
- Powerplant: 1 × LeBlond 70-5 5-cyl. air-cooled radial piston engine, 70 hp (52 kW)
- Maximum speed: 100 kn (115 mph, 185 km/h)
- Service ceiling: 9,000 ft (2,700 m)
- Rate of climb: 580 ft/min (2.9 m/s)
References
- ^ Avrocar: Canada’s flying saucer : the story of Avro Canada’s secret projects.
- ^ “Round aircraft designs”. Archived from the original on 2 April 2012. Retrieved 7 September 2011.
- ^ “Announcing the New Arup”. Popular Aviation. XVII (2). Chicago, IL: Aeronautical Publications Inc: 92. August 1935. Retrieved May 31, 2025.
- ^ Hoffmann, Raoul (September 1935). “A Low Aspect-Ratio Plane”. Popular Aviation. XVII (3). Chicago, IL: Aeronautical Publications Inc: 158. Retrieved May 31, 2025.
- ^ “Low AR-planes”. Retrieved 7 September 2011.
- ^ Experimenter. December 1957.
{{cite journal}}: Missing or empty|title=(help) - ^ Bernard L Rice (March 1987). “Milt’s Little Bird”. Sport Aviation: 43.
- ^ “KSBN airport”. Archived from the original on 22 March 2012. Retrieved 7 September 2011.