First KC-46A tanker aircraft taking shape at Boeing

Boeing workers in Everett, Wash. on Wednesday loaded a wing spar for the first U.S. Air Force KC-46A aerial refueling tanker, starting production of that aircraft and achieving another milestone toward delivering 179 tankers during the next 14 years.

The KC-46A is based on Boeing's commercial 767-200ER, a proven airframe in service as an airliner, freighter and tanker. Boeing has delivered more than 1,050 767s worldwide.

The spar, the main structural component of the wing, is 82 feet 5 inches long. On the aircraft, it provides critical support for flight loads and the weight of the wings when the plane is not flying.

The program’s next major contractual milestone, the Air Force’s Critical Design Review, starts next month.

Boeing employees are also preparing the 767 production line for assembly of the next-generation tanker’s aft and forward body structures. The aircraft will be assembled in November and roll out of the factory in January.

Next June, Boeing will begin installation of military-unique systems on the aircraft at Boeing Field in Seattle as well as testing. First flight for the fully provisioned tanker is scheduled for early 2015, with first delivery in 2016.

Boeing expects to build and deliver the first 18 KC-46As by 2017 and a total of 179 by 2027 if all options under the contract are exercised.

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