Warner Scarab 110, Radial 7 Engine

Type: Reciprocating, 7 cylinders, radial, air cooled

Power rating: 82 kW (110 hp) at 1,850 rpm

Displacement: 6.92 L (422 cu in.)

Bore and Stroke: 108 mm (4.25 in.) x 108 mm (4.25 in.)

Weight: 124.7 kg (275 lb)

Warner Aircraft built four models of radial, air-cooled engines. Three were seven cylinder engines known as the “Scarab,” “Super-Scarab,” and “Super-Scarab 165.” The Scarab was introduced in 1928 as a replacement for the surplus World War I-era Curtiss OX 5 engines that dominated the small, moderately priced aircraft market in the late 1920s. The new engine was successful in aerial contests across the country, including the 1930 National Air Races in Chicago, where Scarab-powered aircraft placed first in 14 events. The Monocoupe 110, Cessna AW, Stinson Junior SM-2, Travel Air W-4000, Fairchild 24 C8A, and Mohawk Pinto M-1-CW all used the Scarab.

This Scarab artifact powered the Ingalls/Alfaro X-13 cabin monoplane. David S. Ingalls entered the Heraclio Alfaro-designed airplane in the Guggenheim Safe Aircraft Competition of 1927-29, which encouraged the use of new technologies, such as high-lift devices, to improve the safe handling characteristics of aircraft.