Emirates Airlines, Dubai\'s national carrier kicked off the Dubai Airshow with an order for 50 Boeing 777-300 extended range aircraft, said the airline\'s Chief Executive Officer.Although the deal is listed at $18 billion, Bahrain News Agency learns that the actual price would be much lower, since airlines generally negotiate a steep discount for such mega orders. On Sunday, the opening day of the airshow, the announcement was made by Emirates Chairman and CEO Sheik Ahmed bin Saeed Al Maktoum.The carrier is Boeing\'s largest customer for the wide-body 777. Its young fleet also includes Airbus A330s and A340s, and the double-decker A380.According to Fairs and Exhibitions Aerospace, the 12th Dubai Airshow was opened by the UAE\'s Vice President and Prime Minister and Ruler of Dubai Shaikh Mohammed bin Rashid Al Maktoum, Shaikh Moahmmed bin Zayed Al Nahyan, Crown Prince of Abu Dhabi and the Deputy Supreme Commander of the UAE armed forces and the King of Spain Juan Carlos.The five day airshow is being held at the Airport Expo. The 13th expo, said a communique, was decked in the nation\'s national flag colours – celebrating the UAE\'s 40th anniversary which falls on December 2.