Introduction
Everyone loves an underdog story, or in this case...an underhog story? The story of the A-10 Thunderbolt II, or more commonly known, Warthog is gritty, tough, and inspiring. This poor aircraft was mocked and laughed at by all upon it's introduction in 1976. So much so that even the pilots that were ordered to switch to the A-10 were reluctant because of it's lacking "sexiness". In fact the nickname Warthog, or Hog, came about because of the comparative ugliness of the fighter compared to that of other fighters of the day like the F-14 Tomcat (talk to me Goose),
F-15 Eagle,
and the nimble F-16 Falcon.
Just a quick look at these few iconic aircraft that were introduced around the same time and you begin to see why the A-10 was so...disrespected. I mean, the A-10 compared to these supersonic fighters looked...stumpy.
I hope by the end of this, you'll understand this aircraft in a different way. The bird that overcame all odds, bullied amongst it's peers, mocked, and threatened with retirement again and again, not only survived, but won the hearts of the nation and military. The resilience of this plane is unparalleled both in and out of combat.
Mission
It's important to understand that the A-10 looks so different than it's siblings because it was designed for a very specific and different mission than the others, close-air-support. The aircraft was designed during the height of the Cold War as an attack aircraft. The Air Force was clear from the beginning that the design would prioritize cost over performance as it was believed that the ability to mass produce and maintain would be a significant advantage against the Soviet Union. As a result, the aircraft was designed with as many "off the shelf" parts as possible. Because it was intended to provide close air support to the troops on the ground, this would put it close to enemy fire as well. Therefore, the aircraft was built to take a beating, with redundancy laced throughout the design.
It's mission was to be available to the ground troops at a moments notice, which meant it had to be able to operate at, or near, forward operating bases, many of which, with dirt and gravel runways. It had to be able to render any kind of resistance inert, and do so accurately to avoid friendly fire. And finally, true to the adage "don't dish it if you can't take it", it had to be able to take a beating and get back to safety. Well friends, I'm here to tell you, the A-10 can dish and equally take the hits found in battle.
Armament: Dishing It
The A-10 Warthog sports, as its primary weapon, the General Dynamics GAU-8/A Avenger. It may be better said, that the GAU-8/A dons the A-10 Warthog since the planes fuselage is literally designed and built around the gun. I don't even know where to begin with this gun. The A-10 was designed to incorporate this weapon system from the beginning. The Avenger (which is a fantastic name for a gun)
is a 30 mm hydraulically driven, seven-barrel Gatling-style cannon that delivers roughly four thousand 30x173 mm cartridges every minute. Forgive me for a second while I geek out about this gun, but this is the Tim "the tool-man" Taylor edition of the Gatling Gun.
This is one of the most powerful aircraft cannons ever flown on an aircraft capable of crippling enemy tanks with its depleted uranium armor-piercing bullets.
It was designed to be most efficient for a 4,000 ft. slant range with the A-10 at a 30-degree dive, and will place 80% of it's shots within a 40 ft. diameter circle on that attack run. The Gun, as it is referred to by the operators, takes up approximately 16% of the A-10s empty weight. Due to the significant weight of the gun, it plays a critical role in the weight and balance of the A-10. When the gun is removed for inspection or maintenance, a jack has to be installed beneath the airplane's tail to prevent the aircraft from tipping back on its tails.
The average recoil force of the GAU-8/A is 10,000 lbf “pound-force” (45 kN), which is slightly more than the output of each of the A-10's two TF34 engines of 9,065 lbf (40.3 kN). While this recoil force is significant, in practice the standard 1 - 2 second burst slows the aircraft by only a few miles per hour in level flight. Don’t worry, the magazine only holds up to 1,174 rounds, and the gun fires at a fixed rate of 3,900 rounds per minute. At this rate, the pilot has about 18 second of continuous fire. That's 18 seconds of a third engine pointed in the opposite direction of flight!
Because the recoil of the gun is so intense, special care was taken with the barrel alignment. If not properly aligned the recoil force of the gun could push the entire plane off target during the firing run. The gun is mounted slightly to the port side of the fuselage centerline, with the active firing barrel lying directly on the aircraft’s centerline. The gun is bore-sighted such that recoil forces do not impact the aircraft pitch or yaw when fired. This configuration leaves space for the front landing gear, which is mounted off-center on the starboard side of the fuselage.
It's important to take a minute and realize we have only talked about one of the weapons the A-10 uses during a deployment. It is generally the pilots favorite weapon, and if it isn't clear by now, mine as well.
Other Weapon Options
The other 10 under wing hard point mounts can sport a plethora of weapon variations.
Here is an impressive list of the ordinance the A-10 may have at it's disposal.
The AGM-65 Maverick air-to-surface missile is a commonly used munition for the A-10. The Maverick missile is targeted via infrared. During operation Desert Storm, pilots used the Maverick's infrared camera as a "poor man's FLIR" (forward-looking infrared camera) for night missions when the aircraft was not equipped with a dedicated FLIR cameras for night vision.
Hydra 70 rocket pods.
GPS and laser-guided bombs, such as the:
ALQ-131 Electronic countermeasures (ECM) pod under one wing
Two AIM-9 Sidewinder air-to-air missiles for self-defense under the other wing.
I wish I had the time and space to go into each of these weapon systems, as they are all incredible, but I highly recommend clicking the links and just skimming the overviews to understand the "flex" this unique aircraft is carrying under its wings.
Survivability: Taking It
The A-10 is extremely battle-hardened, it is able to survive direct hits from armor-piercing and high-explosive projectiles up to 23 mm. It has double-redundant hydraulic flight systems, and a mechanical system as a backup if hydraulics are lost. In the event of a complete hydraulic failure, the pilot can still control the aircraft using a manual reversion control system. The pitch and yaw control engages automatically while the roll control is pilot-selected. The aircraft is designed to be able to fly with one engine, half of the tail, one elevator, and half of a wing missing!
This pilot of this A-10 flew it safely back to base on manual reversion mode when she experienced dual hydraulic system failure during a flight in Operation Iraqi Freedom.
The cockpit, gun mechanics, and parts of the flight-control systems are protected by 1,200 lb. (540 kg) of titanium aircraft armor, referred to as the "bathtub". The armor makes up almost six percent of the aircraft's empty weight. Any interior surface of the tub directly exposed to the pilot is covered by a multi-layer nylon mesh shield to protect against fragmentation.
The unusual location of the General Electric TF34-GE-100 turbofan engines decreases ingestion risk and also allows the engines to run while the aircraft is serviced and rearmed by ground crews. The engines' 6:1 bypass ratio contributes to a relatively small infrared signature. Furthermore, because of their position, exhaust is directed over the horizontal tail further shielding it from detection by infrared surface-to-air missiles. The engines are shielded from the rest of the airframe by firewalls and fire extinguishing equipment.
The engines' exhaust nozzles are angled nine degrees below horizontal to cancel out the nose-down pitching moment that would otherwise be generated from being mounted above the aircraft's center of gravity and avoid the need to trim the control surfaces to prevent pitching.
All four of the A-10's fuel tanks are located near the aircraft's center and are separated from the fuselage. Compromised fuel transfer lines self-seal; if damage exceeds the tanks sealing capability, then check valves prevent fuel from flowing into a compromised tank. Most of the fuel system components are located inside the tanks so that fuel will not be lost due to component failure. Special polyurethane foam lines both the inner and outer sides of the fuel tanks, retaining debris, restricting fuel spillage, and minimizing the event of an explosion in the event of damage. In the event of all four main tanks being lost, there are still two more self-sealing sump tanks contain fuel for 230 miles (370 km) of flight.
Since the A-10 operates very close to enemy positions, where it is an easy target for ground troops, surface-to-air missiles (SAMs), and enemy aircraft, it carries both flares and chaff cartridges.
In its entire lifespan only seven of these bulldog aircraft have been shot down. This is a plane whose role is to fly close and into the fight. Not stand off at a distance taking accurate shots and then rocketing away at Mach...anything. Low, slow, tough, and mean. Seven is an impressive number considering its operating environment.
Final Points
Two Seat Variant
There is one two-seat variant of the A-10 in existence, designated the YA-10B. The original name of the YA-10B was actually the A-10 N/AW, which designated it as the Night and Adverse Weather variant. I like that the even the name suggested it wasn’t going to last long…”NAW, I don’t think this will last.”
The modification work consisted of rebuilding the forward airframe to accommodate a second cockpit. The canopy had to be changed from the clamshell type to a side-opening type divided between the cockpits. The A-10 N/AW was equipped with ACES-II type ejection seats that were designed to fire through the canopy! The vertical tails were rebuilt with a 20-inch extension added to the top. And a plethora of avionics upgrades were done to allow the aircraft to fly when it usually couldn’t. Finally, the aircraft retained the GAU-8/A 30mm Gatling Gun, but had a smaller ammunition drum with a capacity of 750 rounds. All this was done in the space of 3 months!
Although the A-10 N/AW test program was successful, the program was canceled because of advancements in night attack equipment and the A-10 N/AW was re-designated the YA-10B in the 1980s.
Later the USAF explored options to modify more A-10s into two-seat variants as trainers, but the program was cancelled before any more were modified. Which means all A-10 pilots have their first flight in the A-10 as solo flights (no instructor). Training is performed in a different dual engine jet and with extensive A-10 simulation flying.
The only two-seat variant of the A-10 lives at the Air Force Flight Test Museum at Edwards Air Force Base in Mojave CA.
Future
As of June 2017, it was announced that the A-10 will be kept in the Air Force's inventory indefinitely...whatever that means. The A-10 has been threatened with retirement a handful of times, but true to it's character, it has survived. The Warthog has been threatened with replacement by the F35 Lightning II, MQ-9 Reaper, the F-16 Falcon, and the F-15E Strike Eagle. In 2007 the USAF expected the service life of the A-10 to end in 2028. Later, in 2013 and 2015 more proposals to retire and replace the A-10 were pushed by congress. However, it was determined that operating the F-35 as a replacement would be too expensive to operate in day-to-day roles. In 2016 the Air Force deferred the final retirement of the aircraft until 2022 when the A-10 would be replaced by the F-35 on a squadron-by-squadron basis. But as stated at the beginning of this paragraph, in 2017 the A-10 was saved with the announcement that it would remain part of the Air Force inventory for the foreseeable future. I'm sure many Marines and Army Personnel are happy to hear they will still have this versatile weapon in their arsenal when they need air support.
Whatever the future holds for this iconic aircraft, it has certainly earned its spot in history as well as the respect and hearts of pilots and ground troops everywhere.
References
-Stephens World Air Power Journal Spring 1994, pp. 47-58
-Stephens, Rick (1995). A-10 Thunderbolt II. World Air Power Journal. p. 18. ISBN1-874023-54-9.
-"Fact Sheet: General Electric GAU-8/A "Avenger" 30mm Cannon". Hill Air Force Base. Archived from the original on 2011-06-04.
-"GAU-8/A Avenger". National Museum of the USAF. Archived from the original on 2010-04-16. Retrieved 2009-09-14.
-Bell 1986, p. 64.