PW generique

Pratt & Whitney is considering building an engine for the Airbus SAS A350 long-haul plane to challenge Rolls-Royce Holdings Plc (RR/)’s monopoly on the new aircraft, people familiar with the plan said.
Pratt & Whitney would offer an engine based on its PW1000G geared turbofan technology, said the people, who asked not to be named because the plan isn’t public. A decision to formally pursue the program may come as soon as this year, one of the people said.
Airbus had originally sought a second engine offering to Rolls-Royce’s TrentXWB on its A350. It had failed to persuade either General Electric Co. (GE), which powers the competing Boeing Co. (BA) 777, or Pratt & Whitney, which was tied up developing the geared turbofan. Airlines including Air France-KLM (AF) have said they’d welcome a choice because it would give them leverage on maintenance, a major source of revenue for Rolls-Royce.
Airbus, based in Toulouse in France, would have to sign off on the Pratt plan before airlines could opt for the engine. The company is “happy that the one engine we have on offer has already achieved 617 sales,” spokeswoman Marcella Muratore said. “However we have always said that we would consider other offers if they are competitive in terms of performance.”
“As Pratt & Whitney looks ahead to powering future wide- body applications, we will scale the geared turbofan architecture to the required thrust levels,” the company said in an e-mailed request for comment. “We continue to keep all airframers informed of our progress on the PW1000G family, including studies with Airbus for potential wide-body applications.”
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Pratt & Whitney’s A350 engine would have to be more than twice as powerful as its existing versions. The company, a subsidiary of Hartford, Connecticut-based United Technologies Corp. (UTX), has undertaken studies that show the leap can be made even if technical hurdles must be overcome, one person said.
The engine maker remains interested in using its technology to power big jets, Bob Saia, who oversees Pratt’s next- generation products, said in an interview this month. Pratt decided not to compete for a spot on the upgraded version of Boeing’s 777 due around the end of the decade, a program drawing interest from GE and Rolls-Royce, the industry leaders.

Pratt & Whitney will continue working on the next generation of
geared turbofan engine technology despite its exclusion from the Boeing 777X re-engining competition.

The early success of the PurePower PW1000G
series in the narrowbody market masks a key limitation. The 3:1 ratio
used by the PW1000G reduction gear is insufficent to power widebody
aircraft or a next-generation single-aisle.

P&W is conducting "due diligence" studies on a new reduction gear
with an at least 4:1 ratio to power the next generation of its
commercial aircraft, says Bob Saia, P&W vice president of next
generation engines.

The 25% upgrade ratio applies a change in the architecture of the
reduction gear. The PurePower 1000G series employs a five, fixed gears
in a star configuration. The next generation will use an all-moving
planetary gear to achieve the higher reduction gear ratio, Saia says.

Such a new gear will be inherently more fuel-efficient than current technology.

"That's probably worth something on the order of 5 to 6% better fuel efficiency," Saia says.

P&W did not use such a gear at the outset years ago for several
reasons, not least because it was more risky and airlines were already
having trouble accepting the reduction gear technology in the first
place.

Boeing's plan to introduce the 777X by the end of the decade was too
fast for P&W to support with an all-new engine architecture, Saia
says.

"We really neeeded to do due diligence on this technology profile," he says.

In addition to the gear, P&W also is working to increase the
overall pressure ratio (OPR) inside the core of a next generation engine
to 60:1, he says. The existing PurePower architecture features an OPR
at 45:1.