Pratt & Whitney and Bombardier have continued negotiations with Qatar Airways during the show as they try to salvage the airline's planned CSeries order after an impasse over engine maintenance costs.

"If the airframe delivers everything we want but the maintenance costs on the engine will be higher than what we want to pay, then we have an issue," says Qatar Airways chief executive Akbar Al Baker. "So until we tie up the whole package as one deal, Qatar does not order the aircraft."

P&W president David Hess says that "conversations" are ongoing: "We had discussions with Bombardier about this again on Monday and we continue to work with that customer to see if we can bring in that order."

The engine maker concedes that there has been scepticism over its claims that the geared turbofan will cost 20% less to maintain than current engines. P&W says that the GTF will deliver $1.5 million in annual savings per aircraft, split 50/50 between reduced fuel burn and lower maintenance costs. It estimates that the PW1000G has six fewer rotating stages than the rival CFM International Leap X advanced turbofan, and 50% fewer aerofoils.

"There is scepticism, because [the cost saving claim] is a big number," says Hess. "They wonder how do we really do that."

Hess says that when P&W explains the details and "take them through the data" of the engine's design, configuration and operating temperatures "the scepticism kinda goes away".

He says that once all the data on the engine is shared, "he only thing that goes back in is the gear system, which we've tortured now in our labs for 20 years and basically maintenance free".

Hess says that P&W has now convinced potential customers and "I think we've convinced Airbus and convinced Embraer and others that the number is real". However Boeing is noteworthy as it is not specifically mentioned by Hess as being among the converts.

Source: Flight Daily News