It's all over but the crying. Last week, Airbus delivered a crushing defeat to Boeing (NYSE: BA) in the race to sell, and deliver, the most planes in the first half of 2011. So far, Boeing's European nemesis has outsold Boeing by a factor of three. But how long will it keep the lead?

Round 2
I mean, they call these companies a "duopoly" for a reason. Over the coming months, there's a whole series of contests coming up in which Boeing could close the gap, or even overtake its rival. The one dominating headlines right now involves AMR's (NYSE: AMR) quest to overhaul its single-aisle fleet with 250 new 737s and/or Airbus A320s. At a $15 billion value, this is a big deal.

From Boeing's perspective, it's a question of loyalty. Will AMR stick with the "exclusive provider" contract it inked back in 1996? Or will it abandon Boeing, lured away by a better deal from Airbus? Airbus will likely offer cut-rate pricing to break up AMR's all-Boeing fleet and open the door to future sales. Meanwhile, AMR will face a true Faustian bargain if it can't get a good price from Boeing. Adding Airbus to its fleet would increase training and maintenance costs for the flier, and mark a turn away from the strategy that has for years helped rival Southwest Airlines (NYSE: LUV) stay profitable as everyone else floundered.

Round 3 ...?
At the same time, Delta Air Lines (NYSE: DAL) is mulling a plane order of its own. The No. 2 airline (after United Continental (NYSE: UAL), which bought its planes two years ago) is looking to replace perhaps 200 planes of various sizes.

... and 4?
Meanwhile, in the contest that no one's talking about, but everyone's been thinking about for years, Ireland's Ryanair continues to wait in the wings. Once again, the magic number is 200 planes. Once again, the battle will be fought between Boeing's 737 and Airbus's A320.

Outside the ring
With more than 650 new plane contracts up for grabs, dominance in the international airplane market is still up for grabs. Which horse should you bet on? Based on the valuations I see at Boeing and Airbus, I'd actually suggest you opt out entirely, and invest instead in one of the guaranteed winners. Whoever grabs this or that plane sale, chances are they'll be buying engines from United Technologies (NYSE: UTX) or General Electric (NYSE: GE).

Click here to see which of these firms I prefer -- and why.

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