Pegasus Takes Flight

March 22, 2019

A KC-46 tanker lifts off from Boeing’s Everett, Wash., production facility on Jan. 25, headed to its first duty at McConnell AFB, Kan. Photo: Brian Everstine/staff

EVERETT, Wash. —

The first operational KC-46s took off from their production facility in Everett, Wash., en route to McConnell AFB, Kan., accompanied by VIPs on board and bid adieu by a cover band playing inside Boeing’s massive factory. Almost eight years after Boeing won the initial $3.5 billion contract to build the next-generation tanker, and two years past the original delivery date, the Air Force had finally accepted the first KC-46 delivery.

“We’re excited,” said Air Mobility Command boss Gen. Maryanne Miller at the Boeing ceremony in Everett. “We can’t wait to get this airplane to McConnell, and we can’t wait to get after it.”

Boeing plans to deliver about three aircraft per month through the end of 2019, 36 aircraft in all, with 16 more to follow in the present contract. Eventually, the Air Force plans to field 179 of the 767-based tankers, which are supposed to help phase out today’s KC-10 Extender fleet.

But while the first jets made themselves at home at McConnell and Altus AFB, Okla., and as operational testing continues at Edwards AFB, Calif., the Air Force and Boeing are still figuring out how to fix three major deficiencies:

  • Glare that makes the remote remote vision system hard to use in certain lighting conditions.
  • Inadequate sensor sensitivity , which can prevent the boom operator from recognizing when the boom scrapes a receiving aircraft.
  • A boom design problem that makes it difficult to refuel slower-flying A-10 aircraft, which weren’t anticipated to be in service when the KC-46 came on line.

While the Air Force and Boeing were working through these deficiencies, a new problem at the company’s production facility forced the Air Force to stop taking new tankers just weeks after the first delivery. In late February, the Air Force announced it had found foreign object debris, items such as tools or trash, an aircraft that it had already accepted. Will Roper, assistant secretary of the Air Force for acquisition, technology, and logistics, said the service needed to review Boeing’s correction plans and find the root cause of the problem before accepting more of the tankers.

The problems with the aircraft’s state-of-the-art refueling system could still lead to more delays and could cost Boeing tens of millions of dollars in penalties, in addition to the more than $3.6 billion in cost overruns the company has already had to absorb.

However, none of the remaining deficiencies are showstoppers, both company and Air Force officials insist.

“We have 1,000 flying hours, 4,000 refuelings,” Air Force Secretary Heather Wilson said. “We’re ready to take the next step, which is to get it in the hands of the airmen and to start operational test.”

The Air Force is withholding up to $28 million per aircraft until deficiencies are corrected, funds Boeing can receive later if corrections are made in a timely manner, according to the Air Force. Multiplied across all 52 jets in the contract, the total penalty could approach $1.5 billion.

Getting to a “yes” on delivery required negotiating a way forward on the deficiencies, and the solution was to separate the boom problem from the remote vision system, Roper said.

The boom problem was the Air Force’s fault. Boeing met the stated requirement. But the requirement did not anticipate the need to continue to refuel A-10 Warthogs that date back to the Vietnam era.

The problem with the remote vision system, however, is a design issue, and Boeing continues to work on solutions. Under certain circumstances, the boom operator’s ability to see refueling probes link up with the boom can be impaired by glare. When the sun hits the camera at certain angles, the image degrades, making it difficult for boom operators to tell if the boom is scraping a receiving aircraft.

Wilson said the system is safe and useful “as it is,” and operators have developed workarounds. For example, crews cannot refuel while flying directly away from the sun.

Air Force scientists, acquisition officials, and Boeing engineers have worked for months on a measurable fix through hardware and software changes, Roper said. That team has set nine critical performance parameters to ensure the remote vision system will meet Air Force requirements. Boeing is focusing its efforts in the first half of 2019 on development to address the problem, said Mike Gibbons, Boeing’s KC-46 vice president.

“We have a lot of work to do on RVS,” Roper said. “There is still design work to do—hardware and software to meet those nine critical performance parameters—so we will keep a lot of technical focus on that.”

The boom issue arises due to the fact that the Warthog is much lighter and flies slower than other aircraft. As a result, it is more difficult for the A-10 to disconnect after refueling.

The Air Force will design a new actuator that will be more sensitive and make it easier for the A-10 to disengage. Anticipated as a simple fix—the Air Force has had to address similar issues before—it could still take up to four years to complete, officials say.

The Air Force faces a growing need for aerial refueling that top officials say cannot be quenched by the current fleet. The “Air Force We Need” plan that Wilson shared in the fall calls for 74 more operational Air Force squadrons, including 14 more refueling squadrons.

“Aerial refueling will be the biggest shortfall in our Mobility Air Forces,” Wilson said in September.

Already, limited availability and capability affect both operations and training.

Pacific Air Forces Commander Gen. Charles Q. Brown said increased tanker capacity and capability are prerequisites to gaining “the flexibility” to span the vast Pacific Theater.

“Tankers are important, not just for the day-to-day piece, but also from an operational perspective,” he said.

Gen. Maryanne Miller, AMC commander, (speaking); Leanne Caret, CEO of Boeing Defense, Space, and Security; Dennis Muilenberg, Boeing CEO; and Kevin McCallister, CEO of Boeing Commercial Airplanes, celebrate the acceptance of the first KC-46s on Jan. 24 at a ceremony prior to the flight to McConnell AFB, Kan., the next day. Photo: Brian Everstine/staff


The first tankers, tail numbers 15-46009 and 17-46031, left Boeing’s production facility on a cold and foggy morning on Jan. 25, with a KC-135 from McConnell leading the way. Air Force Chief of Staff Gen. David L. Goldfein said the arrival of the aircraft marked a “new era” of refueling for the service.

“We’re a global power because of global reach,” Goldfein said. “Our allies count on it, and our adversaries know it.”

The Air Force picked McConnell to be the main operating base for the KC-46 in 2014 and invested $267 million to build three new hangars, new dormitories, a control tower, and a fuselage trainer, among other facilities, according to the 22nd Air Refueling Wing. The 344th and 924th Air Refueling Squadrons will be the first units to fly the aircraft.

At Edwards, operational test crews began Phase III certifications early this year, with plans to fuel 11 aircraft types, including F-22s and F-35s. To date, KC-46s have already refueled the A-10, B-52, C-17, F-15, F-16, F/A-18, and KC-135.


Two weeks after the first delivery to McConnell, Air Education and Training Command kicked off its KC-46 era at Altus AFB, Okla., accepting two of the new tankers for the service’s sole Pegasus training schoolhouse.

Altus is also home to C-17 and KC-135 training and schoolhouses, which are running at full capacity as the first cadre of instructor pilots and maintainers begins training on the KC-46. Altus crews expect the KC-46s to begin flying immediately and to quickly integrate with the other aircraft.

“Rapid global mobility starts here, because we train the preponderance of mobility crew members,” said Col. Eric A. Carney, the commander of the 97th Air Mobility Wing at Altus, in an interview. “The C-17 can’t do training without tankers, and tankers can’t do training without the C-17. So this is an ideal place to learn together. … The KC-135 schoolhouse and the C-17 schoolhouse will make the KC-46 schoolhouse better, faster.”

As soon as the tankers touched down, Altus began a two-month familiarization period, during which maintainers, aircrew flight-equipment specialists, police, fire department, and airfield-operations personnel could get used to operating with it, said Maj. Jacob Piranio, the operations flight commander at the 56th Air Refueling Squadron. This time period gave initial Boeing-trained aircrews the chance “to get comfortable” with the plane, Piranio said.

The initial pilots were selected from a small group-tryout process and came from a variety of backgrounds, including RC-135s, B-52s, E-3s, and others, he said.

The first class of boom operators went through a similar process and tryouts, followed by familiarization at Altus, said MSgt. Jonathan Lauterbach, boom operator and noncommissioned officer in charge at the 56th ARS.

For maintenance, Altus recruited airmen from C-17, KC-135, and KC-10 backgrounds, along with FAA-certified airframe and power plant airmen, said Donnie Obreiter, the KC-46 maintenance flight chief.

New KC-46 aircrews are excited to operate on the new aircraft, they said. While it has a shorter range and lighter total fuel load than the tri-engine KC-10, it features a modern digital cockpit, enhanced situational awareness thanks to advanced sensors built into the fuselage, and it can deploy countermeasures to defend itself. It also has a radar-warning receiver. The tanker comes from the factory with Link 16, the primary data link used by Air Force and allied aircraft.

Before the tankers arrived, Altus was the home to C-5 and C-141 flight training units. The Oklahoma base was chosen because it already had viable infrastructure from its previous schoolhouses.

“We were able to mod some existing hangars, able to capitalize on some infrastructure that was already here,” Carney said. New military construction included simulators, classrooms, and a fuselage trainer, some of which had been completed years before the first KC-46s touched down.

“There’s a lot of excitement,” Carney stated. “Everyone has been anxious to get the new aircraft here, and we’ve had the personnel here, and the maintainers here, and the boom operators who have been ready to get their hands on it and get their fingerprints on the plane. And now the time is coming.”