Scaled Composites has revealed plans to apply hybrid gasoline-electric propulsion on "future unique aircraft configurations" after completing initial ground and flight tests of the Model 367 BiPod.

Hybrid systems have emerged as Scaled's favoured approach to the problem of integrating electric motors into personal aircraft, a long-time pet project of Scaled founder Burt Rutan, who retired in April.

The first such system has been integrated onto the BiPod roadable aircraft, but the company is not done evaluating other propulsion options.

"Ultimately, the BiPod configuration will provide a unique propulsion system testbed in an operational flight vehicle, providing Scaled Composites experience with a number of different powerplants and associated systems," the company said in a statement.

Integrating electric propulsion into a personal aircraft was the last in a series of bold and high-profile aerospace projects launched by Rutan, who founded Scaled in 1983 after designing a series of popular kit-built aircraft in the 1970s.

The BiPod is intended to serve as a propulsion testbed, but also attempts to tackle the challenge of fielding a practical car that also can fly.

By using a twin-boomed fuselage, the BiPod is configured with a centre of gravity optimized for driving on four wheels. A gasoline engine is embedded in each fuselage to drive the rear wheels and propellers on the horizontal stabilizer. Lithium batteries in the nose provide additional energy for take-off, driving the aft propellers remotely without the combustion engine's need for a driveshaft and gearbox.

Scaled designed the BiPosd to achieve a maximum speed of 402km/h (200mph), and travel 1,126km (700mi) in aircraft mode.

The BiPod joins a growing number of alternative propulsion projects underway in the global aerospace industry. Yuneec has already fielded the e430 all-electric aircraft. Meanwhile, Cessna has launched the electric Skyhawk proof and concept and EADS has flown the electric Cri-Cri demonstrator.

Solar propulsion concepts include the Solar Impulse manned aircraft and the Boeing/Qinetiq Vulture, an unmanned demonstrator launched by the Defense Advanced Research Projects Agency.

Source: Flight International