US Airways has chosen Rolls Royce Trent 700 engines to power up to 30 Airbus A330-200 twinjets.
The deal has been valued at around $2bn (around £984m) and includes two long term service agreements for the Trent 700 and RB211 engine fleets.
The A330 order comprises engines for 15 firm and up to 15 additional aircraft.
The deal is the latest in a series of engine orders placed by US Airways since mid-2007. The firm said it showed ongoing confidence in its product.