USAF Accepts First KC-46, Though Deficiencies Could Persist for Years

A KC-46A touches down at Yokota AB, Japan, on Oct. 23, 2018. The Air Force on Thursday accepted the first KC-46, clearing the way for delivery to McConnell AFB, Kan., within weeks. Air Force photo by Yasuo Osakabe

The Air Force has accepted the first KC-46A Pegasus tanker from Boeing for operational testing, two years behind schedule and with known deficiencies in the boom operator’s vision system and the boom itself that could take years to resolve.

The decision to accept the jet, announced Jan. 10 in a short USAF press release, is a “major milestone for our next generation tanker,” the Air Force said, and allows the Air Force to begin operational testing and flight training on the aircraft. The service said the deficiencies “do not prevent the tanker from carrying out its primary mission.”

Delivery of the first aircraft to McConnell AFB, Kan., and an official ceremony to mark that occasion, will take place as early as the end of January. Boeing said in a statement that nine more aircraft are undergoing Air Force acceptance testing, and four could be delivered to Altus AFB, Okla., as early as next month.

Boeing and the Air Force initially expected to take the first delivery of a KC-46 in early 2016, and the fixed-price contract called for 18 aircraft to be delivered by the end of 2017. The schedule has repeatedly slipped as deficiencies were discovered in testing.

The Air Force accepted the first aircraft with deficiencies in the “remote vision system” and the boom’s ability to properly sense “axial loads.”

“We have identified, and Boeing has agreed to fix at its expense, deficiencies discovered in developmental testing of the remote vision system,” the service said. “The Air Force has mechanisms in place to ensure Boeing meets its contractual obligations while we continue with initial operational testing and evaluation.”

The Air Force is withholding up to $28 million per aircraft—about 20 percent of the cost of each tanker—until the deficiencies are corrected, Air Force spokeswoman Capt. Hope Cronin said. If applied to every aircraft on contract, this could total up to $1.5 billion. ?Boeing will be able to receive those funds later if the corrections are made in a timely manner, she said, adding there is “an agreed-upon cost” for each airplane.

Boeing has so far absorbed more than $3.2 billion in cost overruns on the fixed-price KC-46 development program.

The January 10 event acceptance is known in the trade as a DD250, for the form the Air Force signs to accept an airplane. It is not uncommon for a DD250 to have deficiencies noted. A decision to accept an aircraft with defects is made at the service’s discretion.

The remote vision system is necessary on the KC-46 because, unlike the KC-135 or KC-10, the boom operator sits at the front of the aircraft, behind the cockpit. The series of cameras provide the boom operator with a three-dimensional view of the rear of the airplane, wingtip to wingtip, as refueling takes place. The cameras also allow the operator to see what’s going on in blackout conditions, using thermal cameras.

Two problems persist with the remote viewing system. Under certain lighting conditions, and when the sun is at a particular angle, the boom operator’s view of refueling could be impaired. Also, boom operators couldn’t tell during testing if the boom was scraping the receiving aircraft outside the protected area around the refueling receptacle. This problem could damage stealth coatings on a low-observable aircraft, ruining or degrading its ability to conduct its mission. Boeing has said a software update could address this issue.

Another issue involves the inability for the boom operator to detect additional loads put on the boom by the KC-46 pilot, and sensing the stiffness of the refueling boom during initial contact.

The Air Force expects the implementation of solutions to these deficiencies to take “approximately 3-4 years to complete,” though it does not project any delays to delivery schedules as a result of these solutions, Cronin asserted.

The decision to accept the aircraft was made in consultation with Ellen Lord, Undersecretary of Defense for Acquisition. She made the call because Patrick Shanahan, Acting Defense Secretary, has recused himself from actions regarding Boeing, where he worked for 31 years before retiring as a senior executive.

Pentagon spokesman Lt. Col. Mike Andrews said in a statement that the Department is in “complete agreement” with the Air Force about the delivery of the aircraft. The Pentagon “remains committed to providing the most cost effective platforms” for the taxpayer while also delivering the “best capabilities” to the military, Andrews said.

So far in flight testing, six KC-46s have completed more than 3,800 flight hours and offloaded more than four million pounds of fuel to nine different aircraft in day, night, and covert flights, Boeing said in a release.

“This is an exciting and historic day for the Air Force and Boeing, as we hand over the first of many KC-46 tankers,” Boeing CEO Dennis Muilenburg said in the release. “I’m proud of the dedication and commitment by our enterprise-wide team, and we’re honored to provide this valuable and capable aircraft to our customer.”

The Air Force said Thursday it expects the initial 18 aircraft to be delivered by the end of 2019.

The service in September awarded Boeing $2.9 billion for 18 more KC-46s plus spares, support gear, spare engines, and Wing Air Refueling Pods. Contracts for the first two production lots—seven and 12 aircraft—were awarded in 2016 and the third—for 15 aircraft—was awarded in 2017. Delivery of 179 total aircraft is expected by the end of 2028.

The Air Force and Boeing recently finished Phase II of flight certification at Edwards AFB, Calif., and is beginning the next phase of testing focused on 11 total aircraft.

“We look forward to working with the Air Force, and the Navy, during their initial operational test and evaluation of the KC-46, as we further demonstrate the operational capabilities of this next-generation aircraft across refueling, mobility and combat weapons systems missions,” Boeing Defense President Leanne Caret said in the release.

McConnell AFB has been preparing for the arrival of the aircraft, having completed 16 military construction and facility projects at a cost of $267 million since 2014. These include a fuselage trainer, hangars, and simulators, among others.

“We stand ready,” Air Mobility Command boss Gen. Maryanne Miller said in October. “Aircrews are excited, we’re excited to get it.”