Boeing Co (BA.N) won 50 percent more firm orders than its arch-rival, including a $14.7 billion bulk buy from United Continental (UAL.N) announced not at the show but in Chicago on Thursday, helping it recover ground after falling behind last year.

EADS' (EAD.PA) Airbus won a long-awaited new customer for the largest version of its future A350, Hong Kong's Cathay Pacific (0293.HK), and on Thursday announced a raft of smaller orders.

The aerospace industry's biggest event was, as expected, a chance for Boeing to rack up strong orders for its fuel-efficient 737 Max narrowbody, its answer to the Airbus short-haul offering, the A320neo, which stole the show in orders in 2011.

Boeing said it took firm or provisional orders for 285 MAX jets and said it now had 649 firm orders, compared with 1,454 for the A320neo which gained a year's start as the two planemakers opted in succession to put fuel-saving engines on their most-sold jets.

Underscoring one of the key areas of growth anticipated by aerospace suppliers, United said its 150-plane order that included a purchase of 100 Boeing 737 MAX aircraft was aimed at replacing older aircraft in its fleet.

Long-awaited fleet replacements by U.S. airlines following a prolonged period of retrenchment are one of the main reasons - alongside growth in emerging markets - that aerospace executives remain confident despite the economic turbulence in Europe.

Yet with order books already full and economies beginning to feel the effects of Europe's debt crisis, the spotlight shifted to how Airbus and Boeing will meet planned production increases to deliver all the aircraft they have sold.

"It is the end of the beginning," said aerospace analyst Nick Cunningham of UK-based Agency Partners, adding, "You get the sense here that the best part of the order cycle is over".

Airbus and Boeing, which battle for the bulk of a jet market estimated at $100 billion a year, have long trumpeted their resilience to a faltering global economy.

Until now, buoyant demand has bolstered their argument that airlines need to modernise their fleets in order to survive high fuel costs and that growth in Asia and the Middle East can offset weakness in the United States and Europe.

But the quietest Farnborough Airshow for years suggests the good times are coming to an end as the euro zone debt crisis drags on, banks become increasingly wary of financing long-term, costly aircraft orders and Chinese growth starts to slow.

"This is a much more quiet type of air show," Damien Lasou, global managing director for aerospace and defence at Accenture, told Reuters.

"We are seeing a certain disconnect between the order book of the manufacturers and the real growth we are seeing in the airline market," he said, adding more airlines could go bust and some existing orders could get delayed or cancelled.

Airbus and Boeing reported a total of $35 billion firm orders and $21 billion in provisional orders at the July 9-15 show, where business focuses on the first four days.

At last year's comparable event in Paris they bagged $67.5 billion in firm orders and provisional ones worth $43 billion, dominated by a flood of orders for the Airbus A320neo. Since then airline profits have shrunk considerably.

"We weren't expecting 700 orders," said Airbus Chief Executive Fabrice Bregier. "We are in a very competitive market right now, with two companies which don't make gifts to each other."

Although most publicity has been on revamps of popular models such as the A320neo and 737 Max, the manufacturers need to sell a lot of their existing models in order to keep production plans intact and ensure a smooth transition.

Airbus confirmed it had set a target of selling 300 standard A320s this year and sales chief John Leahy said it was on course to achieve this.

"We have sold more than 500 A320neos since we launched the neo," Leahy told Reuters. "We're happy with results of the show, we weren't looking for any great numbers," he said, adding that more orders could come over the next few weeks.

Boeing plans to increase production across its product range by 30 percent by 2014 and expressed confidence in being able to manage the transition between the old and new 737 models.

"There is no question that deliveries are a very important part of our business going forward," Boeing Commercial Airplanes marketing vice-president Randy Tinseth said.

"I think we have done a very good job in managing the bridge and I think maybe our competition is not doing as well."

The airshow raised concerns over further delays to the Airbus A350 programme after the company said it had encountered problems in drilling holes in the wing to fasten the skins to the structure.

But Airbus said it was not altering its schedule for its answer to the Boeing 787 Dreamliner which flew at the Farnborough Airshow. The A350 is due in service in mid-2014.

"Although EADS is not changing its A350 guidance at this point, we think investors are sensitive to any negative developments on the programme, having been through similar issues on the Boeing 787 and A380," said RBC analyst Robert Stallard. (Additional reporting by Tim Hepher; Editing by Elaine Hardcastle, David Holmes and Tim Dobbyn)

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