Curtiss R-600 Challenger
Intended as a lower-cost medium-power engine for smaller commercial and sport aircraft, the 6-cylinder air-cooled 2-row configuration provided better dynamic balance and smoother operation. The R-600 Challenger received Approved Type Certificate No. 5 in 1928, and powered a variety of aircraft, including the Curtiss Robin, Fledgling and Tanager, the Curtiss-Wright Sedan 15-C, Command-Aire Model 5C3 and Eastman Sea Rover E-2. The R-600 displaced 603 inĀ³ (9.9l), weighed 420 lb (191 kg), and produced 185 hp at 2,000 rpm.