The world\'s biggest air show began with a huge order for the Airbus superjumbo, deals for Boeing\'s troubled Dreamliner, and a clap of thunder and lightning on Monday. The two rivals announced a slew of orders at the Paris Air Show, where they traditionally battle for supremacy in the booming market for airliners, but Airbus came out on top on day one with at least $18.3 billion in orders compared to $6.1 billion for Boeing. The aviation giants are fighting to get an edge in the market for long-haul wide-body planes at this year\'s show, which started north of Paris under black skies, thunder, lightning and torrential rain. Airbus took centre stage with big deals, including a mammoth provisional order for 20 A380 double-decker superjumbos by aircraft financing group Doric with a catalogue price of about $8.0 billion (6.0 billion euros). The European manufacturer also said US aircraft leasing group ILFC had ordered an extra 50 of its new A320neo airliners -- which are not yet in service -- at a catalogue price of $5.0 billion. German airline Lufthansa said it had completed an order, announced in March, for 100 medium-range Airbus A320 aircraft, worth 10 billion euros at list prices. This took its total firms orders so far to $18.3 billion. If the A380 deal is firmed up -- as both companies said it would be -- total orders come to $26.3 billion. The head of US firm Boeing\'s commercial aviation division Ray Conner said the show was going to be a \"great competition\" and added that airlines would \"benefit from the fact that both companies are going to have a good wide-body product line.\" \"I think we have the better products and at the end of the day, hopefully the better product wins,\" Conner told reporters on Sunday, and on Monday Boeing announced several orders for its next-generation 787 Dreamliner, its new 737 MAX and its existing long-haul 777 plane. Japan\'s Skymark Airlines said it had put down firm orders for four 737 MAX aircraft, becoming the first Japanese airline to set its sights on Boeing\'s new medium-haul plane, in a deal worth $402 million at catalogue prices. Leasing firm GECAS, meanwhile, ordered 10 787 Dreamliners worth $2.9 billion at list prices, while Qatar Airways announced orders for nine 777s -- two firm, and seven options, worth $2.8 billion. Boeing and Airbus traditionally vie for the highest number of orders at the Paris Air Show. However, deals are usually concluded at less than the list prices, depending on discounts and tough negotiations over made-to-measure features. At last year\'s Farnborough show in Britain, which alternates with the Paris event, Boeing came out on top, securing orders worth around $35.5 billion, more than double the Airbus haul of $16.9 billion. This year, Airbus staged a show of its own three days before the event at Le Bourget, stealing the limelight from Boeing and other plane manufacturers with the successful maiden flight of its new A350 long-haul plane on Friday. Airbus is pinning its hopes on the fuel-efficient A350 to compete in the long-haul sector where it is still lagging behind Boeing. It has positioned the plane for the market between the popular 777 and the 787, hoping to steal share away from both planes, arguing that its craft will consume six percent less fuel than the 787 and a quarter less than the 777. The A350 is expected to conduct a fly-by of the air show towards the end of the week, hoping to woo potential customers. Boeing is also entering the show in bullish mood as it seeks to move on from its difficulties with the trouble-prone Dreamliner. Technical problems with overheating batteries forced the worldwide grounding of the Dreamliner fleet in a major setback for the Seattle-based manufacturer. Boeing\'s strategy is to offer its clients a wider choice of long-haul airliners, but Tom Enders, boss of Airbus parent company EADS, said \"the jury was still out\" in terms of the firms\' respective market situation. \"It\'s premature to draw any conclusion and it\'s not necessarily the one who has more products who is also better positioned on the market,\" said Enders. This year\'s event will also see Canada\'s Bombardier hoping to win orders in the medium-haul segment with its CSeries, a plane with 110 to 130 seats. But the Paris air show, in its 50th edition this year, is not just about commercial battles and the long-awaited A400M military transport plane will also likely provide a highlight as it takes to the skies. The market in unmanned surveillance drones will also be in focus after three top European defence companies urged the creation of a European programme to manufacture the craft, currently available only from Israel or the United States. The Paris Air Show runs from June 17 to 23. It is expected to welcome some 350,000 visitors through its cavernous show halls.