Fresh off the recent slugfest at the Paris Air Show last week, the action heated up again this week for airline investors as the battle for the sky continued to rage between Boeing (NYSE: BA) and archrival Airbus.

The prize? Contracts to manufacture at least 250 aircraft, equivalent to around $15 billion in revenue. It recently surfaced that AMR (NYSE: AMR) subsidiary American Airlines started negotiations with the two aerospace titans, soliciting bids to replace approximately 38% of its entire fleet.

And while the revenue figures thrown around from the potential contracts seem eye-popping, the value to the eventual manufacturers' respective bottom lines might look more like fine print. According to those in the know, American solicited a bid from Airbus before approaching Boeing. In this way, it appears American intended to force Boeing's hand into delivering another bottom-of-the-barrel bid similar to its epic undercutting of Airbus for the Air Force KC-X refueling contract earlier this year. And we all know how that ended.

Broader implications
The impact for the winner probably extends further than the contract alone. At a time when Boeing finds itself mismanaging its operations again (read: Dreamliner) and again (read: KC-X), its back looks to be increasingly against a wall. It sorely needs a legitimate success to restore both investor and customer confidence in its ability to deliver as promised.

On the other hand, a major victory on Airbus' part could signal a major shift in power, as the company makes increasing inroads into the hangars of America's major airlines. Its A320neo stole the show at last week's Paris Air Show with promises of increasing fuel efficiency by 15% -- especially beneficial at a time when soaring fuel prices serve as an unwelcomed headwind for the industry.  

Boeing and Airbus also have their effective duopoly on the line from both north and south. Canada's Bombardier secured several orders for its new CSeries in Paris last week. And Brazilian airplane manufacturer Embraer (NYSE: ERJ) has been gaining momentum in emerging markets, having booked 125 net orders in the year ending in March.

Foolish takeaway
Neither company wants to see its market share erode, but they both (especially Boeing) want to avoid the kind of overaggressive bidding that will now cost Boeing shareholders around $300 million. As long as the companies avoid undercutting each other, one thing is for sure: American Airlines will make someone's day.

To keep tabs on the situation, you can add Boeing, AMR, or Embraer to My Watchlist.

Andrew Tonner has no position in any of the companies mentioned in this article. Motley Fool newsletter services have recommended buying shares of Embraer. Try any of our Foolish newsletter services free for 30 days. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.