AgustaWestland has provided further detail on the enhancements it has made to its AW609 tiltrotor which it claims will “significantly” improve the performance of the type.

Modifications have been made to the AW609’s vertical stabiliser, which has seen its trailing edge trimmed to keep it in line with the similarly reshaped tail cone, saving weight and reducing drag, it says, “with no detriment to handling qualities”.

The tiltrotor’s exhausts have also been lightened and lengthened “making for an exhaust plume that is directed further aft than before,” says programme manager Clive Scott. He adds: “There is also a wave-form inner exhaust that creates a much better mix of the exhaust plume.”

A further alteration has been undertaken to the spinner cones on the AW609’s prop-rotors with the addition of “eyebrows” in front of each blade to improve the airflow over the cone and nacelles.

The modifications have been performed on its second flight-test example and have so far accumulated around 12h since trials of the revised configuration commenced on 25 July.

“The simulated performance of the modifications has been confirmed through approximately 12 hours of dedicated flight testing. The performance of the aircraft has improved significantly as a result of these modifications,” says Scott.

The design changes will be incorporated onto the two additional prototypes currently undergoing final assembly in Italy, it adds.

So far the two flying examples, based in Italy and the USA, have accumulated over 800h and AgustaWestland is “on track” to complete the expansion of the AW609’s flight envelope in the fourth quarter as new Pratt & Whitney Canada PT6 engines, Rockwell Collins avionics and a fly-by-wire system from BAE Systems are integrated.

Certification is scheduled for 2017.

Source: Flight International