Calling it a “new paradigm in aviation propulsion,” test pilot Dick Rutan completed the first flight of the quiet new Graflight V-8 diesel engine from the Mojave airport, on May 2. The engine was installed in a modified Cirrus SR22. The test flight took about 20 minutes, staying at altitudes 5,000 feet and less. The team plans to test-fly the engine for 40 hours over the next three months, then fly it to EAA AirVenture at Oshkosh for a public debut in July. The engine is controlled by a single power lever, and is designed with rugged technologies that will expand time between overhauls to 3,000 hours, the company says. It can be fueled with Jet-A, JP-8, or straight diesel.
Throughout the testing phase, EPS said it will monitor 80 different channels of data on the engine, focusing mainly on pressures and temperatures of oils and coolants, and closely monitoring intake and cooling air. The engineers also will check drivetrain vibrations, horsepower, and fuel economy in flight. At the end of the test phase, EPS hopes to have proven definitively that the fuel savings recorded in over 500 hours of ground testing is equaled or greater in actual flight. Work on the pilot-engine interface will be managed by Dick Rutan. The project was launched by a Wisconsin firm in 2010. The company says it expects the engine to be certified in 2016.
