The A-10 Warthog’s designers understood that battle damage in combat would be inevitable—and overengineered the plane to survive it.

The A-10 Warthog features a highly unusual design philosophy. Most aircraft are built to avoid being hit, and if they are hit, to remain in the air for long enough to fly to safety. The A-10, on the other hand, is built with the assumption that it will be hit, and is designed to carry on with the mission after the fact.

Accordingly, the core concept in A-10 design is redundancy across every critical system. Not only does the A-10 feature backups, but it features different types of backups using different physics. That’s why the A-10 is arguably the most survivable aircraft ever built. No single failure can take the plane down; every function has multiple, independent ways to work.

The A-10 Warthog’s Specifications

• Year Introduced: 1977
• Number Built: ~716 (all variants)
• Length: 53 ft 4 in (16.16 m)
• Wingspan: 57 ft 6 in (17.42 m)
• Weight (MTOW): ~51,000 lbs (23,132 kg)
• Engines: Two General Electric TF34-GE-100 turbofans (~9,000–9,275 lbs thrust each)
• Top Speed: ~420 mph (675 km/h)
• Range: Combat radius: 290 nautical miles (334 miles, 537 km); ferry range with tanks ~2,200 nautical miles (2,532 miles, 4,074 km)
• Service Ceiling: ~45,000 ft (13,700 m) — tactical employment almost always near ground level
• Loadout: GAU-8/A 30 mm rotary cannon (centerline); up to ~16,000 lbs (7,260 kg) of external stores; loadout can include AGM-65 Mavericks, AIM-9M Sidewinder, LAU-131 seven-round rocket pods, Hydra 70 2.75″ rockets/APKWS, JDAM/GBU kits, gun pods, flares/chaff, LITENING targeting pod, and external tanks
• Aircrew: 1 (pilot)

About the A-10’s Many Redundancies

An aircraft’s flight controls change its pitch, roll, and yaw by moving the ailerons, elevators, and rudder. In the A-10 Warthog, the primary flight control system is hydraulic, where fluid under pressure moves the control surfaces. This system is needed because air loads at 300-plus knots are too strong for human muscle.

The A-10 features two independent hydraulic loops. However, in a failure scenario, where both hydraulic lines are severed, the A-10 can revert to a mechanical backup, which allows the pilot to provide flight control inputs through cables that move the flight control surfaces. The mechanical controls offer the pilot a slower response, but the aircraft remains controllable, allowing the pilot to return to base.

This is different from most aircraft, because most aircraft only feature redundant systems of the same type. In other words, a different fighter jet like the F-16 Fighting Falcon might have backup hydraulics in case the first set failed. But the A-10 uses different mechanics entirely. For example, if the hydraulic flight controls fail altogether, the mechanical still works; there is no shared failure mode. This design avoids a correlated failure. Redundancy is not a simple duplication, but a diversity of function that allows the A-10 to survive nearly any scenario. 

The A-10 was built around structural redundancies, too. The wing structure features three separate spars, or internal load-carrying beams. With three spars, the A-10 can lose one spar or sections of wing skin, and still remain structurally sound enough to fly. The load is simply redistributed across the structure. And the structure is designed to degrade gradually, not just fail suddenly.

Redundancy is built into the engine design, too. The Warthog’s engines are mounted high on the plane and far apart—making it unlikely that one hit will take out both engines. And if one engine is destroyed, it’s less likely that the surviving engine will ingest debris from the failed engine. Naturally, the Warthog can fly home on just one engine. The engines are also identical, which simplifies replacement. 

Even the fuel system is redundant. Typically, a punctured fuel tank rapidly loses fuel. But, like most modern aircraft, the A-10 features self-sealing tanks, with material that expands to plug holes. The cross-feed system reroutes fuel between tanks when necessary, and features an automatic shutoff that can isolate a damaged fuel line. And just in case, the A-10 features a sump tank with emergency reserves, good for some 20 minutes of flight time. Like everything else, in philosophy, the fuel system is segmented and failure-proofed. 

Similar design concepts were applied to the electrical and system routing. Wiring paths are physically separated so that a single hit cannot disable all systems. Again, redundancy is spatial, not just functional.

The Warthog’s Low Failure Rate Speaks for Itself

The A-10 is remarkable in that its design philosophy assumes failure, requiring multiple independent recovery paths. Of course, the need for so much redundancy is clear: the A-10 is far and above the most vulnerable of any US Air Force aircraft to ground fire, given the low altitude at which it must operate. This means that building the plane to avoid damage would be silly; it will take damage no matter what. But it can fight through that damage, relying on the idea that at least one system will survive.

Of course, the A-10 is by no means invincible; a half-dozen of the aircraft were downed during the Gulf War in 1991, and another was lost in Operation Epic Fury as part of the “Dude 44” rescue effort in early April. Yet the plane’s remarkable success—with only a handful of the more than 700 built ever shot down, despite regular daytime contact with enemy forces at low altitude—speaks to the effectiveness of its design.

About the Author: Harrison Kass

Harrison Kass is a writer and attorney focused on national security, technology, and political culture. His work has appeared in City Journal, The Hill, Quillette, The Spectator, and The Cipher Brief. He holds a JD from the University of Oregon and a master’s in Global & Joint Program Studies from NYU. More at harrisonkass.com.

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