Boeing began the first day of the Dubai Airshow to announce the first major sale of news of the five-day event.
Emirates has ordered 40 Boeing 787 Dreamliners in a deal worth around $15bn (£11.3 bn) at list prices.
The Dubai airline’s chairman, Sheikh Ahmed bin Saeed al-Maktoum, said that the plane had been chosen on the Airbus A350.
He had been expected to announce a large order for the highest potential Airbus A380 at the press conference.
Airbus desperately needs more orders for the A380, the largest passenger plane in the skies.
The Franco-German company and Emirates are understood in an intense final negotiations to have a proclamation prepared for this week’s show.
Emirates, the largest airline in the Middle East, is already the biggest customer of Boeing 777 aircraft, with 165 in service and another 164 in order.
Sheikh Ahmed, said on Sunday the order raises the cost of the purchase of aircraft Boeing $90bn. Some of the new 787 will be used to replace the aircraft, while others are used to expand the airline’s network.
Boeing welcomed the agreement, in which Kevin McAllister, commercial director of air division, said that he would maintain many jobs in the united States.
Deliveries of the aircraft are scheduled to begin in the year 2022.
Also on Sunday, Azerbaijan airlines said it was the purchase of five Dreamliners, as well as two freighters Boeing, in a deal worth an estimated $2 billion dollars.
In the middle of the display of military hardware and the most recent civilian aircraft, is the traditional rivalry of Boeing and Airbus, which grabs the airshow of the holders.
So far this year, Boeing has won about 65% of new aircraft orders worldwide.
Neither Emirates nor Airbus comment on the status of the rumored A380 order, which will help to protect jobs in the aircraft manufacturer’s plant in the north of Wales, where the wings are made.
Emirates has been the largest customer for the A380, after you have bought 142 of the nearly 320 that are in service or in production line. The last order for the highest potential came two years ago, when Japan ANA bought only three planes.
In July, Airbus said it would cut annual production of the A380 from 12 to eight. Two years ago Airbus was doing the 28 aircraft a year.