The US Air Force (USAF) has cleared Boeing’s troubled aerial refueller, the KC-46A Pegasus, for worldwide combat duty following evaluation exercises.

“We are ready to use this aircraft globally in any fight, without hesitation,” General Mike Minihan, commander of the USAF’s Air Mobility Command (AMC), said on 19 September during an air-defence conference near Washington, DC.

The AMC confirms the milestone, saying the KC-46A is now approved “for worldwide deployments to meet combatant command taskings”, effective from 14 September.

KC-46A McConnel AFB acceptance inspection

Source: US Air Force

A KC-46A acceptance inspection. The jet’s refuelling boom is among the systems that have experienced issues

“The KC-46 now officially joins the rest of the air force’s refueling fleet in meeting combatant command requirements around the world,” says AMC KC-46A team lead Brigadier General Ryan Samuelson. “The KC-46A is a game changer in its ability to transmit and exchange data between networks, arming warfighters with real-time battlefield awareness.”

In June, the AMC said it had approved KC-46As to perform missions for the US Transportation Command, which oversees US military logistics support. Now, the jet is approved for combat missions.

The USAF recently put the Boeing tanker through an “employment concept exercise” in the Middle East. 

Minihan, speaking during a conference held by the Air & Space Forces Association, says he cleared the Pegasus based on its performance during that evaluation, combined with previous exercises in Europe and the Indo-Pacific region.

However, the four-star general says crews have been creative in working around numerous technical issues. “There are still things that need to be addressed,” says Minihan.

He notes the jet’s remote vision system (RVS) – which crew use to control the refuelling boom – does not function adequately in some weather conditions and when the sun is at certain angles. Also, an issue with the aircraft’s operating software creates stability issues when loading cargo.

Those and other problems have been addressed by the AMC to allow for safe operations, and Minihan plans to employ the Pegasus operationally.

“If I can put an incredibly capable tanker in the fight now, why wouldn’t I?,” he says.

The USAF’s civilian administrator, Secretary of the Air Force Frank Kendall, was more blunt in his assessment of the KC-46A. “It has been a very painful experience,” he says.

KC-46A Pegasus connects with an F-15 Strike Eagle for an aerial refueling test over California in 2018

Source: Boeing

A KC-46A Pegasus connects with an F-15 Strike Eagle for an aerial refuelling test over California in 2018

Kendall, who also spoke during the conference, says “Boeing has struggled. They have not performed where they should have.”

The USAF and Boeing have devised a plan to redesign the RVS at no cost to the service. However, the US Government Accountability Office (GAO) has been critical of that proposal, calling the technology immature.

“[The USAF’s] choices mirror those made during the development of the KC-46 that led to the delivery of an aircraft that did not fully meet its requirements, and the air force stands poised to potentially repeat its past mistake,” the GAO says.

In addition to the RVS issue, the KC-46A’s boom is too stiff to refuel lighter aircraft, such as Fairchild-Republic A-10s and Lockheed Martin F-16s.

“Pilots of these lighter receiver aircraft reported the need to use excessive thrust to move their aircraft into position to release fuel from the boom and maintain the refuelling position,” says the GAO. “This additional required thrust can cause the receiver aircraft to lunge forward into the boom and strike it, possibly damaging the receiver aircraft and boom.”

This requires the boom be redesigned, with a fix expected by 2023. A fix for the RVS, known as RVS2.0, is expected to be rolled out by 2024.

Meanwhile, delays have turned the KC-46 programme into a massive money loser for Boeing, with more than $5 billion in charges for which the airframer is on the hook.

Boeing employed a risky strategy on several major defence programmes in recent years, providing what are known as firm-fixed-price (FFP) bids to the Pentagon solicitations. Under an FFP contract, the manufacturer is responsible for covering any unexpected cost overruns or delays.

FFP contracts can leave suppliers liable for cost increases not of their own making, such as those from inflation or supply chain constraints.

In Boeing’s case, the strategy allowed the company to win competitive bids and accelerate a lagging defence business.

However, the tactic exposed the aerospace giant to huge losses. Boeing also took recent charges against its T-7A trainer and VC-25B replacement for the presidential jet, known as Air Force One.