The US Air Force’s future tanker aircraft, the Boeing KC-46A Pegagus, suffers from too much stress – both literally and figuratively. While testing fuel transfer to a Boeing C-17A Globemaster III airlifter, the refuelling boom experienced a higher axial load then expected. This could lead to damage or worse.
Boeing sources have confirmed they are “looking into the issue and solve the problem”, but the physical stress on the aircraft’s premier tool comes shortly ahead of a possible decision for low-rate production (LRIP) of the tanker.
The Pentagon takes a decision in May on whether to give Boeing the green light to produce and deliver the first 18 KC-46As to the US Air Force by August 2017. The aircraft manufacturer thinks to have solved the stress-on-boom-issue this month to safeguard the LRIP and is confident that it will meet the delivery demands.
The second fully configured Boeing KC-46A Pegasus flew for the first time this week from Paine Field, joining the other aircraft in the test program. The total number of flight hours in the program has now reached 440, according to Boeing. Two are now configured as Boeing 767-2Cs and two as KC-46A tankers.
During the flight, Boeing test pilots performed operational checks on engines, flight controls and environmental systems. The flight orginated at Paine Field and ended at Boeing Field near Seattle. The second tanker will help share the test load and receiver certification. The KC-46A should be able to refuel 18 different aircraft with the help of both its boom plus droge and hose refueling systems.
EMD-1, a 767-2C test aircraft, has completed more than 260 flight test hours to date since its first flight in December 2014. EMD-2, the program’s first KC-46A tanker, made its maiden flight on 25 September 2015 and has now completed more than 180 flight test hours. EMD-3, a 767-2C, will begin flight testing later this year.
The Boeing KC-46, the future US tanker aircraft, successfully refueled an F/A-18 aircraft in flight on 10 February. It marks the first time fuel was transferred using the aircraft’s drogue and hose refueling system.
The KC-46 will refuel other aircraft using both its boom and hose and drogue systems. The boom allows the tanker to transfer up to 1,200 gallons of fuel per minute, while the plane’s hose and drogue systems, located on both the plane’s wing and centerline, enables the KC-46 to refuel smaller aircraft such as the F/A-18 with up to 400 gallons of fuel per minute.
On 24 January, the KC-46 refueled an F-16 fighter using its air refueling boom. The refueling flights should lead to a low-rate initial production decision later this year.
Boeing plans to build 179 KC-46 aircraft, named Pegasus when in service.
Success for the US Air Force’s future Boeing KC-46A tanker aircraft on Sunday 24 January; the first actual air-to-air refueling became a fact in the skies over Washington state. Following take off from Boeing Field in Seattle, the KC-46A worked through a series of tests before transfering 1,600 pounds of fuel to a US Air Force F-16 flying at 20,000 feet.
During the 5 hour and 43-minute flight, both Boeing and air force air refueling operators accomplished multiple contacts with the Edwards-based F-16. “The refueling boom’s handling qualities throughout the flight were exceptional,” said Rickey Kahler, Boeing KC-46 air refueling operator who also guided the boom during contacts with the F-16 while sitting in the tanker’s state-of-the-art refueling operator station in the front of the tanker. “The boom was extremely stable – it handled like it was an extension of my arm.”
The KC-46A that accomplished Sunday’s refueling 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 on 25 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.
The US Air Force is to receive 180 KC-46 over the next decade or so as a replacement for old KC-135 tanker aircraft. The KC-46 is named Pegasus in US service. Japan also ordered three KC-46s for the Japan Air Self-Defense Force (JASDF).
The Japan Air Self-Defense Force (JASDF) is buying three Boeing KC-46A Pegasus tanker aircraft from the United States. The order was announced by the Ministry of Defense in Tokyo.
“The KC-46A is the one that satisfied all the necessary requirements as new air-to-air refueling and transport equipment of the Air Self-Defense Force,” a statement reads.
The fact that Tokyo chooses the unproved KC-46 – which is still in preliminary testing in the US – over proven concepts like the Airbus A330 MRTT comes as no suprise. Airbus even dropped out of the race, because according to the European manufacturer, all perimeters were set on the KC-46. Japan already operates a small fleet of Boeing KC-767 tanker aircaft.
The Japanese order – to be put in the country’s 2016 budget – is the first export deal for the new Boeing tanker.