You've got to hand it to Boeing (BA 0.39%). If there's one thing it does, it builds lots of planes -- even if they don't always work right or come in on budget. One of Boeing's latest ventures involves an attempt to stay ahead of rival EADS Airbus' A350-1000, the largest version of Europe's newest plane.

Right now, Boeing has the market cornered when it comes to "mini-jumbos," thanks to the 777, a twin-engine plane capable of going distances similar to that of a four-engine plane. More importantly, the 777 is Boeing's most lucrative plane, according to analysts. To make sure it stays that way, Boeing is planning on rolling out a few upgrades; the 777-9X and the 777-8X. But will these planes prove profitable? Or will Airbus come out on top? 

Photo: Jean-Philippe Boulet, via Wikimedia Commons. 

777 vs. A350
When it comes to comparing the new 777X's with the A350-1000, there are a few key differences to keep in mind. The 777X's will have a metal fuselage with carbon fiber wings, which, according to Boeing, will increase performance but maintain reliability. The A350-1000, on the other hand, will mainly be carbon fiber. Airbus argues that this makes the plane lighter, and cheaper to operate.  

Further, the 777-9X is expected to hold roughly 400 passengers, while the A350-1000 holds 350 passengers. Boeing claims that the ability to carry 400 passengers will increase airline revenue and that the 777X will have "significantly lower operating costs." But Airbus argues that because of its smaller size, the 350-seater A350-1000 plane is the one that will produce more revenue, as it's cheaper to run.  

Finally, both Boeing and Airbus make mini-jumbo, long distance planes, although there's not as much demand for them. Still, with the ability to fly 9,500 nautical miles, Boeing expects the 777-8X to replace its 777-200 LR and fill this niche market. That's in comparison with Airbus' A340-500 that's capable of 9,000 nautical miles.  

Who will rule the sky?
Boeing and Airbus have been rivals for some time, with both companies attempting to dominate the mini-jumbo market. The A350-1000 has had slow sales to start, but ir recently took a swing at Boeing's 777's thanks to an $6 billion order from longtime Boeing customer British Airways. More importantly, this order marked a upward tick in sales as Air Lease (AL 1.06%) also purchased five A350-1000s, and other airlines have starting to show interest in doing the same. Considering Airbus markets the A350-1000 as a 777 replacement, I'm guessing Boeing is feeling a little bruised. 

Battle of the tiny Titans
The latest round in the mini-jumbo battle is just getting started, and who will come out on top is uncertain. Airbus has a head start with orders and should be able to deliver its plane earlier, as Boeing really didn't start marketing its latest designs until it heard about the British Airways order. Following that, Boeing announced its partnership with General Electric (GE 1.44%) and seemed to start taking the Airbus threat seriously -- clearly good news for General Electric. So while the battle is still in its infancy, this is something investors should be keeping tabs on. Especially because both planes could prove highly profitable for their respective companies.