Pratt & Whitney is working to support Bombardier's timeline for launching the single-aisle CSeries project, despite a nearly year-long mismatch in development schedules.

Bombardier has committed to make a CSeries launch decision by the end of the year, and is still evaluating engine candidates.

P&W, meanwhile, is not prepared to formally launch the Geared Turbo Fan (GTF) programme before November 2008. But the manufacturer could accelerate its launch decision by several months to meet Bombardier's schedule.

"We are working to have that capability," says Bob Saia, vice-president of the next-generation product family.

P&W's 20-year-old GTF concept seeks to make seat-kilometre costs plummet by inserting a gear between the low-pressure turbine and the engine fan, allowing each component to spin at its most efficient rate.

The concept, if successful, is expected cut fuel burn by 12%.

The company has reached the halfway point on final assembly of a ground-test demonstrator based on the PW6000, which should be ready for testing from late November to March 2008, Saia says. The company also plans to install a GTF prototype on its Boeing 747 flying testbed in the third quarter.

This timeline means P&W has planned to go ahead with a detailed design launch of the GTF in November 2008, or nearly a year after Bombardier expects to launch its CSeries.

However, Saia notes that P&W's schedule can shift to the left by several months. Although the engine does not enter flight test before mid-year 2008, the company can by custom sell a new engine to a customer before reaching that milestone, he says.

P&W's long-term schedule also meets Bombardier's needs to introduce the 110- to 130-seat family of narrowbodies after 2012. If Pratt launches a 30-month detailed design period in November 2008, a final product should be available by mid-2011, Saia says, or several months ahead of the CSeries schedule.

The development programme requires P&W to shift from the PW6000 core to an all-new architecture based on technology developed under the military-funded XTC67-1 engine programme.

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Source: Flight International