Boeing has formally launched its new 777X family with orders and commitments by four airlines for 259 aircraft at the Dubai air show today.
Boeing chairman and chief executive Jim McNerney says it is the largest launch in "commercial jetliner history".
The firm orders include 150 by Emirates Airlines alone, along with purchase rights for 50 more.
Etihad Airways signed an order for 25 777X aircraft, including the first order for 777-8X.
Qatar Airways signed a letter of intent for 50 aircraft.
Lufthansa, meanwhile, signed an order for 34 777X in September, contingent upon a programme launch.
The 777X family, including the 400-seat 777-9X, long-range 777-8X and 777X Freighter, will all be powered by the GE Aviation GE9X turbofan engine.