An all-composite, six- seat twin developed in secret by Colorado-based Adam Aircraft Industries and Scaled Composites, was unveiled on 5 April at the Californian manufacturer's Mojave site. The aircraft represents a breakthrough in manufacturing techniques, according to Scaled Composites president Bert Rutan.
Incorporating several design and manufacturing innovations, the twin-boomed M-309 was developed and built in only seven months. Two Teledyne Continental pistons drive Hartzell three-bladed propellers in a push-pull configuration, providing centreline thrust in the event of an engine failure.
Adam founder and chief executive Rick Adam says improved safety in twin operations is the prime design driver behind the M-309. "We did several surveys to see where general aviation accidents came from. As a result, the design has got centreline thrust, trailing link, widely spaced "beefy" landing gear and advanced instrumentation that will help with things such as fuel management, ground proximity warning and Nexrad weather data, he says. Meggitt Avionics' new generation integrated cockpit (MAGIC) is at the heart of the cockpit display.
The design also makes the first use of advanced composite manufacturing techniques perfected by Scaled Composites. Rutan says: "This is the first aircraft ever flown in which the primary flight surfaces - the wing, horizontal tail, ailerons and rudders - don't have secondary bonds or fasteners. That's an enormous thing if you are into composites, and it is a huge thing if you are working with the US Federal Aviation Administration on certificating a composite aircraft, because secondary bonding and fasteners are the most difficult to work with."
Describing the single cure design as a "breakthrough", Rutan says the vacuum-bagged, oven-cured resin transfer process is the result of 12 years' work at Scaled Composites.
The prototype was "unveiled" when it flew over Scaled Composites' hangar, the M-309 having made its first flight on 21 March. It will have a maximum speed of 250kt (465km/h), a gross weight of 2,500kg (5,400lb) and range, with instrument flight rules reserve, of about 2,780km (1,500nm).
Certification is expected to take up to three years, says Adam.
Source: Flight International