Pratt & Whitney (P&W) in mid-July will begin the detailed design phase of its PW1000G geared turbofans for the Bombardier CSeries and Mitsubishi Regional Jet (MRJ), in advance of formal engine testing in the middle of 2010.

The engine maker is "in the final stages of preliminary engine design" after completing successful flight evaluation programmes on its in-house Boeing 747 and Airbus' A340-600 test aircraft, says P&W next generation product family vice-president Bob Saia.

Following the flight evaluation, Airbus agreed that P&W had met "all projections we had set for the gear system", says Saia, adding: "We did what we said we were going to do."

Thereafter, P&W disassembled parts of the demonstrator engine, made certain measurements and reassembled it as a display vehicle. The powerplant, logged more than 400 hours of testing, including 120 hours in flight.

The company is now proceeding with the slow "but very thorough" process of margin testing, which aims to push the geared turbofan technology to its limits. "Now we want to know what will cause it to fail," says Saia, noting that this will enable P&W to determine the system's maintenance characteristics.

Bombardier will use the 20,000lb-24,000lb (89-107kN) thrust class PW1500G to power its new CSeries mainline jet, while Mitsubishi is taking the 13,000lb-17,000lb thrust class PW1200G for its MRJ. Both airframers "are very pleased" with the state of the programme and the data gleaned through testing of the geared architecture, says Saia.

P&W is targeting engine certification for the end of 2011. The CSeries and MRJ are scheduled to enter into service (EIS) in 2013.

The geared turbofan is expected to achieve about a 15% fuel efficiency gain over current architectures, but P&W's objective is to improve fuel consumption in the order of 1% to 1.5% per year.

"We think that by EIS of next generation narrowbodies, the engine could have 22% to 23% better fuel burn than current generation narrowbodies. We know we can make it better," says P&W president Dave Hess.

Source: Air Transport Intelligence news