Rolls-Royce challenged general aviation to step up its use of turboprops with the launch at Oshkosh today of a next-generation 350-450 shp turboprop engine named the RR500.
"The RR500 is ideally positioned to capture significant market share in the light, fixed-wing general aviation segment," said Ken Roberts, president of Rolls-Royce helicopter business, which embraces turboprops too. According to the Rolls-Royce ten-year market forecast, 2,500 to 3,000 of these light aircraft will be delivered annually between 2010 and 2020.
"Not only does the RR500 deliver cost-effective turbine power in a lightweight, affordable, compact design, but it also appeals to a broad segment of the market historically limited to reciprocating engines."
The new engine, based on the RR300 turboshaft engine for helicopters unveiled last year, comes in just below the smallest Pratt & Whitney PT6 engines (580-920 shp) and the Walter M601 (500-800 shp). On paper it appears to compete head-to-head with Rolls´s own Model 250 (around 400 shp) that powers various models of Maule, Cessna and Bonanza.
The 250, however, has always been regarded by the general aviation market as "expensive," Roberts said. The RR500 will cost "substantially less" than the 250, due to the clean-sheet design allowing the latest in design, materials and manufacturing techniques. "The Model 250 is very, very popular, and this allows us to offer a lower cost alternative," he said. Industrialization is significantly more advanced now than when the 250 was originally designed, he added.
The RR500 is basically a growth version of the RR300. "We were looking at the 300 shp market but decided that the RR300 was just not big enough to meet the altitude and hot-and-high requirements that many aircraft need," Roberts said. Thermodynamically, the new engine "will be north of 500 shp at sea level," and will offer 400-450 shp for takeoff, around 350 hp for climb, and 320 hp for a cruise speed of 220 kt at 12,000 ft.
"Our preliminary target is new OEM aircraft; retrofits and conversions will be secondary," Roberts said. He is convinced the engine will prove popular as 100LL Avgas becomes harder to find and is eventually phased out. "This engine will burn a wide variety of kerosene-based fuels including the Russian and Chinese blends," he added. "We´ve already had a lot of market interest."
Certification is expected in less than three years.
While RR300 engines are painted blue, the RR500 will be green--a color that is bound to symbolize its benefits for the environment as well.
Rolls-Royce on Monday announced that Rotorway International will explore using the the RR300 turboshaft engine that was launched last year for the Robinson R66 helicopter. Rotorway is the world´s oldest and largest manufacturer of kit helicopters.