Boeing and U.S. Air Force aircrews successfully completed the KC-46A tanker’s first refueling flight in late January. The KC-46A is a multirole tanker based on the 767 that Boeing is building for the USAF to refuel all allied and coalition military aircraft. It is compatible with international aerial refueling procedures and can carry passengers, cargo, and patients. Overall, Boeing plans to build 179 KC-46 aircraft.

Following takeoff from Boeing Field in Seattle, the KC-46A test team worked through a series of test points before smoothly off-loading 1600 lb of fuel to an F-16 fighter aircraft flying at 20,000 ft.

“[The] flight is an important milestone for the Air Force/Boeing team because it kicks off the Milestone C aerial refueling demonstration, which is the prerequisite for the low-rate initial production decision,” said Col. Christopher Coombs, U.S. Air Force KC-46 system Program Manager. “We have a lot of work yet to do, but this is an exciting time for the airmen.”

During the almost 6-h flight, two Boeing and USAF air refueling operators accomplished multiple contacts with the F-16 that confirmed the system was ready to transfer fuel. The air refueling operators “flew” the tanker’s 56-ft fly-by-wire boom downward and waited for the F-16 to move into position before fully extending the boom into its refueling receptacle. The KC-46 offloaded fuel to the fighter and when the fuel transfer was complete, the system automatically turned off the pumps and the operator retracted the boom.

The KC-46A—which will have a cockpit with 787-style 15-in displays—that flew the refueling milestone will soon begin refueling a number of other military aircraft as well, including a C-17, F/A-18, A-10, and AV-8B. Also known as EMD-2, the tanker made its first flight late September 2015 and has now completed 32 flights.

The program’s first test aircraft (EMD-1), a 767-2C, has completed more than 260 flight test hours to date since its first flight in December 2014. EMD-3 and EMD-4 will begin flight testing later this year.

As part of a contract awarded in 2011 to design and develop the USAF’s next-generation tanker aircraft, Boeing is building four test aircraft—two are currently configured as 767-2Cs and two as KC-46A tankers.