Boeing’s [BA] KC-46 next-generation tanker program finished its Phase II receiver certification flight testing after a final set of tests, the company said Monday.

The latest flight tests lasted three weeks and were conducted with F-15E aircraft near Edwards Air Force Base, Calif.

The U.S. Air Force and Boeing started the program’s receiver certification testing in April with F-16s, and since then has conducted tests with the KC-135 Stratotanker, C-17 Globemaster, A-10 Warthog, KC-46 Pegasus, B-52 Stratofortress, and F/A-18 aircraft.

Boeing’s KC-46A tanker refuels an F-15E aircraft during Phase II receiver certification testing out of Edwards Air Force Base, Calif. (Photo: Boeing)
Boeing’s KC-46A tanker refuels an F-15E aircraft during Phase II receiver certification testing out of Edwards Air Force Base, Calif. (Photo: Boeing)

The flight tests involved the tanker and receiver aircraft flying at different airspeeds, altitudes, and configurations to guarantee compatibility and performance through the receivers’ refueling envelopes. The next step is for the Air Force and Aerial Refueling Certification Agency to review test data and paperwork before certifying each aircraft.

Mike Gibbons, Boeing KC-46A tanker vice president and program manager, said finishing this round of test flights is setting the stage for the beginning of Initial Operational Test and Evaluation (IOT&E) tests in 2019.

“We are seeing great progress in both test and production and expect the positive momentum to continue as we begin delivering aircraft,” he said in a statement.

“The Air Force crews were with us every step of the way during this critical testing. It was awesome to see everyone working together as we conducted flights out of Boeing Field and also at Edwards and Minot Air Force bases,” Jake Kwasnik, KC-46 test program manager, added.

The next step in receiver certification testing, Phase III, is expected to be conducted by the Air Force at Edwards in 2019 and will include more receiver aircraft.

Boeing said six test KC-46As have conducted over 3,700 flight hours and supplied more than four million pounds of fuel in flight to receiver aircraft.

Defense Daily previously reported the Air Force earlier downgraded two category-1 deficiencies related to the boom and radial loads as well as the centerline drogue system to category-2 because a workaround solution was established (Defense Daily, Nov. 16).

An earlier target delivery date in late October has passed but a Boeing official previously told Defense Daily the company was working toward the goal of initial KC-46 deliveries starting before the new year.

A Boeing spokesperson told Defense Daily on Monday they still expect to deliver the first tanker before the end of 2018.