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• 10 percent more engine power at altitude; • 850 to 1,650 shaft horsepower; • 33 percent longer time between over- haul, compared to the competition; • the highest power-to-weight ratio in its class. The package may be new, but the con- stituent parts of that package are not. The ATP, says Mottier, "is taking technologies from different (GE) engines and archi- tectures from other engines and putting them together in this new platform." GE Aviation's BGA engine chief contends, "We are doing this at very low risk." That's because the high-pressure ratio compres- sor, the stator vanes, and the cooled tur- bines have more than a billion flight hours on a multitude of GE commercial aircraft engines. The ATP's aerodynamics borrow on more than 150 million hours of field use in commercial powerplants. The engine's modular architecture is based on the CT7 turboshaft, a family of engines that has managed to rack up more than 100 million flight hours — 5 million of them in hot and harsh envi- ronments. ATP gets its compressor from the CT7. ATP is a reverse flow affair, one in which air enters the engine near the back of the powerplant and flows out via exhaust stacks on the side. In that respect it's similar to GE Aviation's H Series of turboprops. All this serves to reduce the risk that can be associated with new powerplants, and cut those unexpected revelations that can wreak havoc on a program. BY THE NUMBERS That bodacious 16:1 overall pres- sure ratio is really efficient, "a step- change," says Mottier. Cooled turbine blades and a multiple-stage low-pressure tur- bine contribute to the ratio. By way of reference, he says competitive engines have over- all pressure ratios in the "9:1 to 10:1 range." Twenty percent less fuel burn and 10 percent more power at altitude are accomplished via computer- control of the engine, coupled with a prop that's integrated into a propulsion control system. "That is a first," contends Mottier. "It's never been done in this [BGA] mar- ketplace." Propulsion control optimizes prop speed, prop pitch and the powerplant itself in a given flight regime — takeoff, descent, and cruise. The way things are right now in this particular BGA niche, "you have a propeller control lever and a throttle." The ATP is linked to a single lever, one that controls both the prop and the powerplant. There's a fundamental difference between overhaul intervals in the BGA market compared to the commercial air- line arena. Business and general avia- 1.316.733.9240 repairs@globalparts.aero www.globalparts.aero BOTTLED We Have Your Solution Exclusive factory authorized repair and overhaul facility for recertification and testing Quick turn hydro-static test services Factory trained technicians Customer unit repairs or in-stock availability for same day exchange to meet your needs AviationPros.com/company/10451249 RENDERING OF the GE ATP. GE AVIATION