The two parties held formal sessions about the design in early July and then announced the review complete, but there were loose ends, and the so-called Critical Design Review wasn't officially date-stamped until Aug. 21. That's still a month ahead of schedule.
Boeing began assembling the first KC-46A at the Everett factory in June and work on the second plane began last month. The company has begun building the second of five test booms at Boeing Field.
Said Air Force Maj. Gen. John Thompson, the executive officer for tankers, in a statement issued Wednesday: "This build and test phase is another critical step toward meeting ... a milestone requiring 18 KC-46 aircraft and all necessary support to be on the ramp, ready to support war-fighter needs," by August 2017. "To succeed will require the focused efforts from all members of the team."
The first 18 tankers are to be built under a fixed-price contract. If all goes well for Boeing, the company will build 179 tankers in all, worth billions of dollars, by 2027. The KC-46A will replace KC-135s, some of which about 50 years old. The Chicago-based company won the competition to supply the Air Force with aerial-refueling tankers, which also will be used as transports, in 2011.
Boeing plans to roll out the first KC-46A from the factory in Everett in January and to finish assembly of the first four by July. Workers at Boeing Field in Seattle then will install additional equipment. Flight testing of the first fully provisioned tanker will begin in 2015.