US low-fare operator JetBlue Airways has tentatively opted for the Pratt & Whitney PW1100G engine for the Airbus A320neo, for which it has an order for 40.
It becomes the first US carrier to choose the powerplant for the type.
The decision also pushes P&W's geared turbofan back into the lead in terms of orders for the re-engined twinjet. It has been chosen for 410 firm aircraft against 385 for the rival CFM International Leap-1A.
Engine selections have yet to be made for the remaining 401 of the 1,196 A320neo-family aircraft on Airbus's firm order book.
JetBlue ordered the A320neo on 27 October but did not disclose a powerplant selection.
But the carrier has signed a memorandum of understanding covering 86 PW1100G-JM engines, as part of an agreement which also includes a long-term maintenance services pact.
"We are confident we've made an excellent choice for our aircraft," said JetBlue chief Dave Barger.
P&W has already landed lessors International Lease Finance and CIT Aerospace as US-based customers for the PW1100G, but JetBlue is the first US airline to choose the engine.
US carrier Virgin America chose the Leap-1A for 30 A320neos while Republic Airways also selected the Leap-1A for 80 aircraft, although Airbus no longer lists the Republic deal as a firm order.
Deliveries of the A320neos to New York-based JetBlue are set to begin in 2018.