Rolls-Royce could face a patent fight if the future UltraFan engine is chosen to power a potential new Boeing aircraft, Pratt & Whitney president Bob Leduc tells FlightGlobal on 31 May.

After investing decades and more than $10 billion to develop and field the geared turbofan engine for several narrowbody aircraft types, P&W now faces a new competitive threat as R-R develops the UltraFan with a fuel-saving power gearbox.
R-R plans to have the UltraFan ready to enter service by 2025, matching Boeing's plans to field a New Midsized Aircraft (NMA) to fill a perceive gap between the 737 Max and 787 families.
But a common technology between the R-R and P&W offerings for the NMA -- a reduction gear in the power system -- sets up a potential clash over intellectual property rights.
"If they do try to sell a geared architecture to Boeing we problably will enforce our rights as we should -- and I'm sure they'd do the same," Leduc says.
The R-R UltraFan features a power gearbox that decouples the rotation speed of the fan and the low-pressure turbine, allowing each module to spin at the most efficient speed. P&W uses the same architecture in the geared turbofan engine, which is offered today on the Airbus A320neo family and four other aircraft families.
Although similar, there still could be major differences. R-R has declined to describe whether the UltraFan's power gearbox employs a star or planetary gear architecture. However, R-R and Liebherr announce a joint venture in 2015 to develop the power gearbox partly at Biberach an der Riss, which is a Liebherr site that specialises in planetary gears. By contrast, P&W uses a star gear design in the geared turbofan engines now in service.
Even if the UltraFan uses a different type of gearbox, P&W could still launch a patent dispute.
"I think it's kind of irrelevant whether it's planetary or star," Leduc says.