The first KC-46 airborne tanker the Air Force would receive has taken its first flight. The plane, which is scheduled for delivery sometime next year, spent three and a half hours airborne after taking off from Boeing Company’s Paine Field in Everett, Wash., Dec. 5.

Once the plane climbed to 39,000 feet – its maximum altitude – test pilots checked its flight controls, environmental systems and engines to make sure they met Federal Aviation Administration (FAA) standards.

The plane is the seventh KC-46 to fly. The first six were used for testing and certification. During those tests, the earlier aircraft logged 2,200 flight hours — refueling F-16, F/A-18, AV-8B, C-17, A-10, KC-10 and other KC-46 aircraft in the process.

Boeing holds a contract to build the first 34 of 179 tankers for the Air Force. Besides refueling, the KC-46 will be capable of carrying passengers, cargo and medical patients. Construction of the aircraft — which is based on the commercial 767 airliner — will take place at Boeing’s Everett facility.