Parts Shortage Paralyzes U.S. Tankers

U.S. Air Force aircraft nose with sun flare — Photo: wideweb / Shutterstock

America’s flying gas stations have missed their own readiness marks seven years in a row, and the reasons hit at the core of how we sustain airpower.

Story Snapshot

The Government Accountability Office says KC-135 and KC-46 tankers missed readiness goals every year from 2019 to 2025.
Parts shortages and aging supply chains dragged down mission-capable rates across both fleets.
Maintenance staffing gaps and training shortfalls made repairs slower and less reliable.
Design and sustainment issues on the KC-46 added friction during a critical transition.

What the watchdog actually found

The Government Accountability Office reported that the Air Force’s two main tankers, the KC-135 and KC-46A, failed to meet availability and mission-capable targets in every fiscal year from 2019 through 2025. The Government Accountability Office linked the shortfall to parts shortages, maintenance workforce gaps, and program delays that slowed the KC-46’s march to full utility. One outlet cited 2024 figures of about 68 percent for the KC-135 and 62 percent for the KC-46, underscoring the scale of the gap.

The Government Accountability Office did more than tally rates. It pressed on root causes. Air Force maintainers cited parts failure as the top driver of downtime, and leaders pointed to critical shortfalls in key components for both aircraft. The report also flagged limited hangar space and other infrastructure limits that stretch turnaround times. That mix forms a classic readiness trap: old jets need more parts, new jets need debugging, and the warehouse chokes on both at once.

Why both old and new tankers stumbled

The KC-135 is proven but old, with complex logistics that depend on vendors who no longer build many items at scale. Each shortage forces cannibalization, which fixes one jet but sidelines another. The KC-46 arrived to relieve pressure, but its remote vision system, boom, and sustainment planning needed more work. The Government Accountability Office warned in 2022 that the Air Force needed to mature these technologies and test them in realistic conditions to avoid readiness drag. Those warnings foreshadowed today’s sustainment grind.

Readiness arguments often hinge on definitions. The Air Force measures “mission capable” as the share of time an aircraft can perform at least one of its assigned missions, not every mission. A jet can fail a “fully mission capable” test and still refuel aircraft in some cases. That nuance matters when the public hears “not available,” but the Government Accountability Office’s bottom line is simple: performance remained persistently below the Air Force’s own standards across the period reviewed.

The human factor: Maintainers make or break the fleet

Fixing jets requires skilled hands, not just parts. The Government Accountability Office tied low readiness to a shortage of trained maintainers and gaps in training pipelines. Units with fewer seasoned technicians take longer to troubleshoot and must rely more on off-jet diagnosis and help desks. That slows sortie generation and increases repeat maintenance. Conservative common sense says you cannot outsource hands-on craftsmanship. The Air Force will need to grow and keep maintainers if it wants faster recoveries.

Retention also matters. When private industry offers better pay and predictable schedules, mid-career technicians leave. That drains experience from the flightline, where judgment saves hours. Any fix list that ignores incentives and family tempo will underperform. The Government Accountability Office’s call for a comprehensive plan recognizes that the workforce is as strategic as the aircraft.

Supply chains, metrics, and the path out

Supply chains built for peacetime tempo will not carry great-power demands. The Government Accountability Office emphasized that the Air Force has not fully assessed these risks or laid out a plan to mitigate them across parts, people, and infrastructure. That critique aligns with broader Government Accountability Office work on aviation sustainment, which urges clear metrics and tighter feedback loops so leaders can see where parts and labor hours vanish before combatant commanders feel the pinch.

Congress has taken notice. A Congressional Research Service brief laid out the stakes: aerial refueling sets the practical range of United States fighters, bombers, and surveillance aircraft. Without reliable tankers, options shrink and risk grows. The near-term path runs through three lanes: close parts backorders faster, stabilize and train the maintainer force, and complete KC-46 fixes so it can shoulder more of the load. The medium-term path demands retooling vendor bases and depots for surge and endurance.

What to watch next

Watch whether depot backorders drop and whether units report fewer cannibalizations. Track maintainer manning and qualification rates against sortie generation. Look for firm schedules and test results on KC-46 modernization closing out known issues flagged in prior Government Accountability Office reports. Expect the Air Force to refine readiness metrics to match real mission demand, while still holding itself to standards that matter in war, not only on spreadsheets.

The United States built global airpower on a simple promise: if it flies, it can fight, and if it fights, a tanker can keep it there. The Government Accountability Office’s findings are a warning light, not a dead end. Fix the parts, grow the people, finish the KC-46’s upgrades, and align metrics with mission. Do those three with discipline, and the boom will be where it needs to be—on time, every time.