DUBAI, United Arab Emirates -- The Dubai Air Show began on Sunday with a $25 billion order for Boeing Co. (NYSE:BA) jets from Abu Dabi-based Etihad Arways. Aviation trade shows are typically used by manufactures and airlines to announce large orders they have been negotiating for months. Etihad announced at a press conference at the show that it has placed firm orders for 56 Boeing aircraft plus options and purchase rights for 26 more. The total value is up to $25.2 billion at list prices, although airlines typically get discounts for orders of this size.

The order includes 25 of the new version of the 777 twinjet, the 400-seat 777-9X and the smaller but longer-range 777-8X. Etihad also bought 30 Boeing 787-10 Dreamliners, which, combined with 41 previous orders for the 787-9 variant, make it the biggest customer for the 787. The Abu Dhabi-based airline, one of the fast-growing breed of Persian Gulf carriers, also ordered one 777 Freighter.

Boeing and its European rival Airbus, a unit of European Aeronautic Defence & Space Company NV (EPA:EAD), are expected to announce orders for hundreds more planes at the trade show, which lasts until Nov. 21.