Staff Writer (Updated: 7/20/2016):
When an initial USAF initiative to acquire Boeing KC-767s aerial tankers fell aground in 2003, a new endeavor was born to develop a new dedicated tanker aircraft through the "KC-X" program in 2006. Both Boeing and EADS/Northrop (on behalf of Airbus) threw their hats into the ring in the hopes of netting the lucrative long-term $40 billion defense contract. Boeing eventually offered their KC-767 while EADS/Northrop delivered their A330 MRTT (this as the "KC-30"). The United States Department of Defense formally selected the EADS/Northrop A330 MRTT/KC-30 proposal and marked the type for development as the "KC-45A" in February of 2008.
The selection of the French Airbus 330 spurred Boeing to action to which the American concern filed a formal protest to American authorities and took their outrage to the public square to help gain a larger audience of favor. The US Government Accountability Office (GAO), citing several miscalculations on the part of the USAF during the initial proposal review and subsequent selection, sided with Boeing and restarted the KC-X bidding process anew.
In the second round of fighting, Boeing resubmitted their KC-767 while EADS - now going it alone without Northrop Grumman support - once again delivered their Airbus A330 proposal. The original selection was overturned in favor of the American-based KC-767 which was formally selected as the winner on February 24th, 2011. For the USAF inventory, the KC-767 is redesignated as the "KC-46A" and, at its core, remains essentially a modernized and militarized version of the original Boeing 767 passenger airliner that began service back in 1982. However, the KC-46 will bring along a new KC-10 style refueling boom as well as cockpit features of the new Boeing 787 "Dreamliner". The initial phase of the KC-46 program will include an "Engineering and Manufacturing Development" portion with a first flight scheduled for sometime in 2014. The USAF intends on procuring some 179 total KC-46 aerial refueling tankers for its current inventory, allowing the release of many of its KC-135 Stratotankers (803 produced since 1957).