CFM International is preparing to detail orders for its Leap-X turbofan, which has yet to receive its first customer for the Airbus A320neo platform.
Virgin America and US lessor International Lease Finance (ILFC) have combined firm orders for 70 A320neo-family aircraft but an engine selection for the jets has yet to be made.
ILFC, which has 100 A320neo-family jets on order, has already chosen the Pratt & Whitney PW1100G for 60 of them but has been holding discussions with CFM to put the Leap-X engine on the other 40.
"We will be announcing several Leap orders in the next few weeks - possibly leading up to, and certainly during, the Paris air show," said CFM, but declined to identify customers or confirm the airframe involved. A variant of its Leap-X engine will also power the Chinese-built Comac C919.
The ILFC order, formally listed on 27 April, covers 75 A320neo and 25 A321neo aircraft. Virgin America ordered 60 A320s in December last year, of which 30 will be A320neos.
Three other customers - India's IndiGo, Lufthansa and TAM - have yet to firm their orders for the re-engined aircraft.
But IndiGo has committed to fitting the PW1100G on all 150 A320neos in its planned order while Lufthansa has opted for the engine for its 25 A320neos and five A321neos.
This means Pratt & Whitney has secured agreements to power 240 of the 332 A320neo aircraft which customers have so far agreed - tentatively and firmly - to acquire.
Brazilian carrier TAM has neither firmed its selection of 22 A320neos nor indicated a powerplant choice.