The Aircraft of MDT: A-10 Thunderbolt II

Welcome to the eleventh regular installment of The Aircraft of MDT. In this series we are taking a look at some of the aircraft that you may spot flying to and from Harrisburg International Airport.

Although the only military aircraft with a permanent home at Harrisburg International Airport is the EC-130J, others are still a common sight. Several factors contribute to the preponderance of military air traffic at MDT: the size of the runway, the presence of the Pennsylvania Air National Guard base, and proximity to Joint Base Andrews. Some military craft come with business at the Guard base, but most come to practice “touch-and-go” maneuvers, in which the plane begins a landing, but then takes off again without ever coming to a complete stop.

One of the military aircraft you may see on the ground or in the sky around MDT is the Fairchild-Republic A-10 Thunderbolt II “Warthog.” The A-10 is a twin-engine, single seat jet used by the United States Air Force for close air support, attacking ground targets in support of nearby troops.

An A-10 Thunderbolt II parked at MDT

Named for the World War II era P-47 Thunderbolt, a fighter that served in a close air support role, the A-10 Thunderbolt II is the first U.S. Air Force aircraft designed and built solely for CAS. The USAF began planning for a new attack aircraft in the mid 1960s. By the early 70s, there were two prototypes competing to be that aircraft, the Northrup YA-9A and the Fairchild-Republic YA-10A. Ultimately, the Fairchild-Republic design won the contract, and production of the A-10 began shortly thereafter. The Air Force received its first A-10 in 1976 and 714 more over the ensuing eight years.

The A-10 can carry a wide variety and large quantity of air-to-ground and air-to-air weaponry, but its primary armament is the 19 foot long 30mm GAU-8 Avenger rotary cannon. The GAU-8 weighs in excess of 4,000 pounds when fully loaded and fires at a rate of 3,900 rounds per minute. When fired from 4,000 feet, 80% of the rounds fired from the GAU-8 will strike within a 40-foot diameter circle. The Avenger cannon was developed for the A-10, and the A-10 is still the only aircraft that carries it.

Its close air support role demands that the A-10 fly in hostile territory at relatively slow speeds and low altitudes. As such, it is built to be extraordinarily hardy. The cockpit is surrounded by a 1,200 pound “bathtub” of titanium armor to protect the pilot from projectile weapons. All of the A-10’s fuel tanks are self-sealing, protected by fire-retardant foam, and designed to be isolated from the rest of the fuel system in the event of damage. All of the aircraft’s flight systems have redundant hydraulic backups and mechanical systems to fall back on in case both the primary and secondary hydraulic systems are disabled. In a worst-case scenario, the A-10 is designed to be flyable even when missing one engine, one elevator, one tail, and half of one wing.

One of the A-10s most distinctive features is its aft section, with its large engines and twin-tail configuration. With the engines placed high off the ground and behind the wing, the chance of foreign object damage is reduced when operating from damaged or otherwise sub-standard runways. The engine placement also supports faster turn-around time in combat. The wings on the A-10 are closer to the ground than they would be if the engines were mounted underneath them, making them more accessible to ground crews. Also, because the engines are out of the way, they can be left running while the aircraft is serviced and rearmed. The twin-tail also provides dual benefits. The most obvious is redundancy, but channeling the engines’ exhaust over the tail planes and between the vertical stabilizers reduces the A-10s infrared signature, making it harder to hit with surface-to-air heat-seeking missles.