Engineered Propulsion Systems (EPS) is preparing two recently purchased Cirrus SR22s as flying testbeds for its clean-sheet design Vision 350 diesel aero engine. One of the airplanes is located at EPS’s New Richmond, Wis. headquarters, while the other is being prepared for flight testing in a hangar at the Mojave airport in California. The engine is on display outside the Innovation Pavilion at EAA AirVenture Oshkosh, mounted to an SR22 firewall.
Instead of designing an engine and offering it to aircraft manufacturers, EPS started the Vision 350 project by polling manufacturers to see what they needed in a high-performance 350+ hp engine. Three key targets emerged: that the engine be weight competitive with other engines in that power category; that it burn any kind of diesel fuel, not just jet-A, to make the engine suitable for operations anywhere in the world; and that it is more efficient than any other gasoline or diesel aero-engine.
The eight-cylinder Vision 350 is Fadec-controlled, twin-turbocharged and liquid-cooled and is geared for optimum propeller speeds and to keep propeller tip speeds low for quiet and efficient operation. Typical fuel consumption is less than 11 gph at 65 percent power, which the company says is 30 to 40 percent more efficient than equivalent avgas engines. The engine will weigh not much more than an avgas engine, according to the company. “The weight delta of the Vision 350 diesel powerplant, as compared to a gasoline engine of similar output, is not significant and is easily overcome by the thermal efficiency of kerosene fuels,” said the company.
EPS is targeting a 2,000-hour TBO for the Vision 350. Certification of the engine should take about 36 months. Famed Voyager pilot Dick Rutan will be the chief experimental test pilot for the Vision 350 program, which should begin in the coming months. The SR22’s nose gear needs to be modified because it normally mounts in the middle of the bottom part of the engine mount for the existing Continental powerplant. EPS is now fabricating the nose gear structure and engine mount and then the new cowling for the diesel engine installation.
EPS has raised two rounds of funding for the Vision 350 program, a spokesman told AIN, and is working on a third. “We’re moving at the speed of cash,” he said. Two aircraft manufacturers have signed pro forma purchase orders for the Vision 350, he said, which means that they will buy the engine if it meets all of the promised specifications. “We have our sights set on several successful new and retrofit programs worldwide,” said EPS president Michael Fuchs.