What might bring top-level executives at Cessna, Cirrus, Piper, Mooney, and other airframe manufacturers to the same tent on a sunny, sticky day at Oshkosh? Apparently, the promise of a new light turboprop engine.
Execs from those companies plus prop-maker Hartzell, and modifiers Tradewind Turbines and O&N and many others gathered July 29 at the Rolls-Royce tent to learn about the company’s plans to introduce the RR-500, a new 400 shaft horsepower turboprop engine for general aviation.
The RR-500 is a growth version of the 300-shp RR-300 engine announced last year that will ultimately power the Robinson R66 helicopter. The RR-500 is meant for airplanes. Ken Roberts, president of R-R Helicopter business, noted that the new engine provides new choices to airframe manufacturers looking to fill in their product lines with a turboprop airplane. The engine brings a greater level of reliability and safety to the market over piston engines, and it provides independence from leaded avgas, he said.
The RR-500 weighs about 250 pounds with typical accessories and can be mated to either a high-speed (2,400 rpm) or low-speed (2,090 rpm) gearbox for various applications. Providing a power-to-weight ratio of 2.0:1, the engine will provide 4 percent better fuel consumption in nautical miles per gallon than a 300-hp piston engine and about a 30-percent increase in range based on a 3-hour trip in a typical four-place single-engine airplane.
Rolls-Royce expects to bring the certified engine to the market in about two and a half years.