Boeing’s KC-46A Pegasus tanker—the aircraft intended to replace the veteran KC-135 Stratotanker in U.S. Air Force service—has been granted FAA approval, the company announced on September 4. With the KC-46A having completed the flying element of the certification requirements in July, the Federal Aviation Administration has issued a supplemental type certificate (STC) for the Boeing 767-2C, verifying that it, and its refueling and mission avionics systems, meet FAA requirements.

Work on the STC began in 2015, including laboratory and ground tests before flight trials. Both the boom and drogue systems were assessed. Six aircraft were involved in the certification flight program. Preceding the STC approval, the baseline 767-2C was granted an FAA amended type certificate (ATC) in December 2017.

“Our Boeing/Air Force test team did an outstanding job successfully leading us through all the requirements, and we appreciate the FAA’s collaboration as well,” said Mike Gibbons, Boeing KC-46A tanker vice president and program manager. “This milestone is important in that it is one of the last major hurdles in advance of first delivery to the U.S. Air Force.”

One more certification hurdle remains, the military type certificate (MTC) that covers features of the aircraft that are not able to be approved by the FAA, including items such as defensive systems and military communications. The flight trials required for the MTC were undertaken in parallel with those for the STC and were also completed in July.

Boeing is currently contracted for 34 KC-46As from an expected requirement for 179. The first aircraft is due to be handed over to the U.S. Air Force in October, more than 16 years after the service selected a tanker version of the Boeing 767 airliner as the KC-135’s replacement. Initial deliveries are due to go to McConnell AFB, Kansas, followed by the main training wing at Altus AFB, Oklahoma. Subsequent bases to operate KC-46As have been named as Pease Air National Guard Station, New Hampshire, and Seymour Johnson AFB, North Carolina, followed by Joint Base McGuire-Dix-Lakehurst, New Jersey, and Travis AFB, California.