WASHINGTON — The U.S. military’s aerial refueling capability has become “brittle” and aged, placing the nation at risk of being unable to sustain combat against a major adversary, a new report from the Hudson Institute said.

The report, “Resilient Aerial Refueling: Safeguarding the U.S. Military’s Global Reach,” sounds several alarm bells about the military’s tanker fleet and its possibly waning ability to help U.S. forces project power around the globe.

“In 2021, the U.S. aerial refueling enterprise is losing altitude,” said the report, released Monday and written by Timothy Walton and Bryan Clark of the institute’s Center for Defense Concepts and Technology.

Since the end of the Cold War three decades ago, the report said, tankers have continued to fly to support both peaceful deployments and wartime operations around the world. As the military settled into an “expeditionary posture” in which forces were more frequently deployed, the Air Force’s tanker inventory shrunk from 701 aircraft to roughly 473, further increasing stress on the fleet. As this high pace of operations became a new normal for the tankers, the Hudson Institute said, the fleet was left with hardly any headroom to take on new missions — including responding to China or Russia, short of war.

“Without significant changes [the Defense Department] risks fielding air forces unable to conduct complex, distributed operations at scale,” the report said. “During conflict, adversaries may be emboldened to exploit vulnerabilities in both the brittle aerial refueling architecture and U.S. operational plans more broadly. As the strength of the U.S. aerial refueling architecture becomes a weakness, U.S. military forces may be incapable of deterring or defeating aggression.”

Another concerning factor is the advancing age of the military’s tankers — the average tanker is 52 years old — and the declining readiness that could result from an increasingly “geriatric” fleet. Delays in bringing the new KC-46 Pegasus tanker into operation could worsen the situation, as older KC-10 Extender and KC-135 Stratotanker airframes are retired before their successor aircraft and their crews are ready.

Hudson said the military — particularly the Air Force — will need to tackle improvements to its aerial refueling from several angles, not just by adding more tankers. The top priority, according to the authors, should be to significantly build up airfields, bulk fuel storage and distribution, and defenses in the Indo-Pacific region — to the tune of another $633 million per year for the next decade, and $400 million annually afterward. This could boost the military’s tanker capacity in the region by 63% in a decade and roughly double it by 2041, the report said — even if it means the Air Force procures fewer tankers to pay for those improvements.

If the Air Force doesn’t expand its refueling posture on the ground as well as distribute its forces and fuel stores, it could find itself cornered by China in a conflict, the report said. In such a conflict, the tanker fleet could find itself with about a dozen airfields from which to operate that have the necessary runway, ramp space and fuel stores, as well as political access, Hudson said.

This would seriously limit how many aircraft tankers could offer support, and place them at greater risk of attack, the report added.

The Defense Department “should improve the [tanker] architecture’s resilience by evolving today’s brittle posture to a more-distributed one that leverages clusters of mutually supporting military and civil airfields on U.S., allied and partner territory, consistent with the U.S. Air Force’s Agile Combat Employment concept,” the report said.

Further distribution of refueling operations would also help the military better protect its fuel stockpiles and keep access to tankers at sea and over-the-shore fuel delivery systems that the armed forces would need to move fuel in significant quantities, the report said.

For example, the report said, the U.S. military’s use civilian airfields in Japan and South Korea would complicate China’s targeting efforts. Some of those airfields could be used for extended operations, it explained, and others could simply be “drop-in” sites for tankers to quickly gas up and take off again.

The Air Force also needs to keep evolving its aerial refueling fleet, Hudson said, by fielding a new tanker to bridge the gap between the KC-46 and the next generation of aircraft known as the KC-Z. This bridge tanker, known as the KC-Y, could either be Boeing’s KC-46 or Lockheed Martin’s LMXT next-generation tanker, a modified Airbus A330 Multi Role Tanker Transport.

Hudson said the bridge tanker must be able to carry out long-range missions and offload large quantities of fuel, since small tankers aren’t enough to meet the Air Force’s requirements. But it warned that the bridge tanker program shouldn’t sap money that would otherwise go to improving tankers already in the fleet, or developing the next-generation KC-Z advanced air refueling tanker.

The Air Force also must speed up development of the KC-Z, the report said; if 18-24 of those aircraft are procured each year, the Air Force could retire KC-135s earlier than expected and lower the overall age of the fleet, which would allow the Air Force to spend more on procurement and less on operations and support.

The report also said that modernizing command, control and communications in aerial refueling would make operations more efficient and effective.

Stephen Losey is the air warfare reporter for Defense News. He previously covered leadership and personnel issues at Air Force Times, and the Pentagon, special operations and air warfare at Military.com. He has traveled to the Middle East to cover U.S. Air Force operations.

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