While some may wonder why Boeing with its NewGen Tanker offering based off a smaller, older 767 design beat out EADS Airbus A330-based KC-45 to win the KC-X contract yesterday, it's likely a matter of fuel efficiency and construction costs associated with housing the new jets.
The difference between the two bids may have come down the difference in fuel consumption, speculated Loren Thompson, defense consultant and analyst at the Lexington Institute. “The Airbus plane burns over one ton more of fuel per flight hour than the Boeing plane. Multiply that by 40 years and that’s a lot of money,” Thompson said. Boeing has argued for some time that its fuel consumption rate would save taxpayers “tens of billions” of dollars over the life of the program.There's also the question of military construction. Remember, both planes was also evaluated by how much cash the Air Force would have to spend to upgrade infrastructure at bases that currently house KC-135s to accommodate the larger Boeing and EADS jets. While the 767 is big, the A330 is a lot bigger. This might mean that modifications to things like ramps and hangars may cost more to accommodate the EADS jet. We won't know for sure on this until the Pentagon tells us.
Another factor may be the number of tails the Air Force can deploy to crowded bases around the world. Naturally, you can fit more of the smaller 767s on a ramp than the A330. Again, we'll see if this played a role in the decision to go with the Boeing plane.