"A-10" redirects here. For other uses, see A10.
| A-10 Thunderbolt II | |
|---|---|
 |
|
| An A-10 from the 81st Fighter Squadron, Spangdahlem Air Base, Germany | |
| Role | Fixed-wing close air support, forward air control, and ground-attack aircraft |
| Manufacturer | Fairchild Republic |
| First flight | 10 May 1972 |
| Introduction | March 1977 |
| Status | In service |
| Primary user | United States Air Force |
| Produced | 1972–1984[citation needed] |
| Number built | 716[1] |
| Unit cost | US$11.8 million (average, 1994 dollars)[2] |
The A-10 was designed around the GAU-8 Avenger, a heavy rotary cannon that forms the aircraft's primary armament. (It is, to date, the heaviest rotary cannon ever mounted on an aircraft.) The aircraft's hull incorporates over 1,200 pounds (540 kg) of armor and was designed with survivability as a priority, with protective measures in place which enable the aircraft to continue flying even after taking significant damage.
The A-10's official name comes from the Republic P-47 Thunderbolt of World War II, a fighter that was particularly effective at close air support. The A-10 is more commonly known by its nickname "Warthog" or simply "Hog". As a secondary mission, it provides airborne forward air control, guiding other aircraft against ground targets. A-10s used primarily in this role are designated OA-10. The A-10 is not expected to be replaced until 2028 or later.
Development
Background
Criticism that the U.S. Air Force did not take close air support (CAS) seriously prompted a few service members to seek a specialized attack aircraft.[3][4] In the Vietnam War, large numbers of ground-attack aircraft were shot down by small arms, surface-to-air missiles, and low-level anti-aircraft gunfire, prompting the development of an aircraft better able to survive such weapons. In addition, the UH-1 Iroquois and AH-1 Cobra helicopters of the day, which USAF commanders had said should handle close air support, were ill-suited for use against armor, carrying only anti-personnel machine guns and unguided rockets meant for soft targets. Fast jets such as the F-100 Super Sabre, F-105 Thunderchief and F-4 Phantom II proved for the most part to be ineffective for close air support, because their high speed did not allow pilots enough time to get an accurate fix on ground targets and they lacked sufficient loiter time. The effective, but aging A-1 Skyraider was the USAF's primary close air support aircraft.[5][6]A-X program
In 1966 the USAF formed the Attack Experimental (A-X) program office.[7] On 6 March 1967, the Air Force released a request for information to 21 defense contractors for the A-X. The objective was to create a design study for a low-cost attack aircraft.[4] In 1969, the Secretary of the Air Force asked Pierre Sprey to write the detailed specifications for the proposed A-X project. However, his initial involvement was kept secret because of Sprey's earlier controversial involvement in the F-X project.[4]Sprey's discussions with A-1 Skyraider pilots operating in Vietnam and analysis of the effectiveness of current aircraft used in the role indicated the ideal aircraft should have long loiter time, low-speed maneuverability, massive cannon firepower, and extreme survivability;[4] an aircraft that had the best elements of the Ilyushin Il-2, Henschel Hs 129 and Skyraider. The specifications also demanded that each aircraft cost less than $3 million.[4] Sprey required that the biography of World War II attack pilot Hans-Ulrich Rudel be read by people on A-X program.[8]
In May 1970, the USAF issued a modified and much more detailed request for proposals (RFP) for the aircraft. The threat of Soviet armored forces and all-weather attack operations had become more serious. Now included in the requirements was that the aircraft would be designed specifically for the 30 mm cannon. The RFP also specified an aircraft with a maximum speed of 460 mph (400 kn; 740 km/h), takeoff distance of 4,000 feet (1,200 m), external load of 16,000 pounds (7,300 kg), 285-mile (460 km) mission radius, and a unit cost of US$1.4 million.[9] The A-X would be the first Air Force aircraft designed exclusively for close air support.[10]
During this time, a separate RFP was released for A-X's 30 mm cannon with requirements for a high rate of fire (4,000 round/minute) and a high muzzle velocity.[11] Six companies submitted aircraft proposals to the USAF, with Northrop and Fairchild Republic selected to build prototypes: the YA-9A and YA-10A, respectively. General Electric and Philco-Ford were selected to build and test GAU-8 cannon prototypes.[12]
The YA-10A was built in Hagerstown, Maryland and first flew on 10 May 1972. After trials and a fly-off against the YA-9A, the Air Force announced its selection of Fairchild-Republic's YA-10A on 18 January 1973 for production.[13] General Electric was selected to build the GAU-8 cannon in June 1973.[14] The YA-10 had an additional fly-off in 1974 against the Ling-Temco-Vought A-7D Corsair II, the principal Air Force attack aircraft at the time, in order to prove the need to purchase a new attack aircraft. The first production A-10 flew in October 1975, and deliveries to the Air Force commenced in March 1976. In total, 715 airplanes were produced, the last delivered in 1984.[15]
One experimental two-seat A-10 Night Adverse Weather (N/AW) version was built by converting an A-10A.[16] The N/AW was developed by Fairchild from the first Demonstration Testing and Evaluation (DT&E) A-10 for consideration by the USAF. It included a second seat for a weapons system officer responsible for electronic countermeasures (ECM), navigation and target acquisition. The variant was canceled, and the only two-seat A-10 built now resides at Edwards Air Force Base's Flight Test Center Museum.[17] The N/AW version did not interest the USAF or export customers. The two-seat trainer version was ordered by the Air Force in 1981, but funding was canceled by U.S. Congress and the jet was not produced.[18]
Upgrades
In 2005, the entire A-10 fleet also began receiving the Precision Engagement upgrades that include an improved fire control system (FCS), electronic countermeasures (ECM), and the ability to aim smart bombs. The aircraft that receive this upgrade are redesignated A-10C. The C model upgrades were to be completed in 2011.[25] The Government Accounting Office in 2007 estimated the cost of upgrading, refurbishing, and service life extension plans for the A-10 force to total $2.25 billion through 2013.[10]
Modifications to provide precision weapons capability are well underway.[26] In July 2010, the USAF issued Raytheon a contract to integrate a Helmet Mounted Integrated Targeting (HMIT) system into A-10Cs.[26] The Air Force Material Command's Ogden Air Logistics Center at Hill AFB, Utah completed work on its 100th A-10 precision engagement upgrade in January 2008.[27]
The A-10 will receive a service life extension program (SLEP) upgrade with many receiving new wings.[28] The service life of the re-winged aircraft is extended to 2040. A contract to build 242 new A-10 wing sets was awarded to Boeing in June 2007.[29] Two A-10s flew in November 2011 with the new wing installed.
Design
Overview
Engine exhaust passes over the aircraft's horizontal stabilizer and between the twin tails, decreasing the A-10's infrared signature and lowering the likelihood that the aircraft can be targeted by heat-seeking missiles fired from the ground. The placement of the engines behind the wings partially shields them from anti-aircraft fire.[30] The leading edge of the wing is honeycomb panel construction to provide strength with minimal weight compromise. Honeycomb panels of this type on the A-10 include the flap shrouds, elevators, rudders and other sections of the fins.[31]
The ailerons are at the far ends of the wings to gain greater rolling moment, as with many aircraft, but there are two distinguishing features. The ailerons are larger than is typical, almost 50% of the wingspan, providing improved control even at slow speeds. The aileron is also split, making it a deceleron.[33][34]
The A-10 is designed to be refueled, rearmed, and serviced with minimal equipment.[35] Also, most repairs can be done in the field.[36] An unusual feature is that many of the aircraft's parts are interchangeable between the left and right sides, including the engines, main landing gear, and vertical stabilizers. The sturdy landing gear, low-pressure tires and large, straight wings allow operation from short rough strips even with a heavy ordnance load, allowing the aircraft to operate from damaged airbases. If runways are damaged in an attack, the A-10 can operate from taxiways or straight roadway sections.[37]
Durability
The A-10 is exceptionally tough. Its strong airframe can survive direct hits from armor-piercing and high-explosive projectiles up to 23 mm. The aircraft has triple redundancy in its flight systems, with mechanical systems to back up double-redundant hydraulic systems. This permits pilots to fly and land when hydraulic power or part of a wing is lost. Flight without hydraulic power uses the manual reversion flight control system; this engages automatically for pitch and yaw control, and under pilot control (manual reversion switch) for roll control. In manual reversion mode, the A-10 is sufficiently controllable under favorable conditions to return to base and land, though control forces are much higher than normal. The aircraft is designed to fly with one engine, one tail, one elevator, and half of one wing missing.[39]Its self-sealing fuel tanks are protected by fire-retardant foam.[40] The A-10's main landing gear is designed so that the wheels partially protrude from their nacelles when the gear is retracted so as to make gear-up belly landings easier to control and less damaging to the aircraft's underside. Additionally, the landing gear are all hinged toward the rear of the aircraft, so if hydraulic power is lost the pilot can drop the gear and a combination of gravity and wind resistance will open and lock the gear in place.[34]
The cockpit and parts of the flight-control system are protected by 1,200 lb (540 kg) of titanium armor, referred to as a "bathtub".[41][42] The armor has been tested to withstand strikes from 23 mm cannon fire and some strikes from 57 mm rounds.[36][41] It is made up of titanium plates with thicknesses from 0.5 to 1.5 inches (13 to 38 mm) determined by a study of likely trajectories and deflection angles. This protection comes at a cost, with the armor making up almost 6% of the aircraft's empty weight. To protect the pilot from the fragmentation likely to be created from impact of a shell, any interior surface of the tub that is directly exposed to the pilot is covered by a multi-layer nylon spall shield.[40][43] In addition, the front windscreen and canopy are resistant to small arms fire.[44]
There are several reasons for the unusual location of the A-10's General Electric TF34-GE-100 turbofan engines. First, the A-10 was envisioned to fly from forward air bases, often with substandard, semi-prepared runways that present a high risk of foreign object damage to the engines. The height of the engines decreases the chance that sand or stones will be ingested. This also allows engines to keep running while the aircraft is serviced and rearmed by ground crews, reducing turn-around time. Without the limitations imposed by engines, the wings could be mounted closer to the ground, to simplify servicing and rearming.[47]
The A-10's fuel system components are protected in multiple ways. All four fuel tanks are located near the center of the aircraft, reducing the likelihood that they will be hit or have their fuel lines severed. The tanks are separate from the fuselage; thus, projectiles would need to penetrate the aircraft's skin before reaching the outer skin of the tank.[40][43] The refueling system is purged after use so that all fuel in the aircraft is protected from fire.[48] All fuel transfer lines self-seal if they are compromised; if a tank is damaged beyond its ability to self-seal, check valves prevent fuel flowing into the compromised tank. Most of the fuel system components are inside the tanks so that fuel will not be lost in case a component were to leak. Most importantly, reticulated polyurethane foam lines both the inner and outer sides of the fuel tanks, retaining debris and restricting fuel spillage in the event of damage. The other source of possible combustion, the engines, are shielded from the fuel system and the rest of the airframe by firewalls and fire extinguishing equipment. Even in the event of all four main tanks being penetrated and all contents lost, sufficient fuel is carried in two self-sealing sump tanks to allow flight for 230 miles (370 km).[40][43]
Weapon systems
Another commonly used weapon is the AGM-65 Maverick air-to-surface missile, with different variations for either electro-optical (TV-guided) or infrared targeting. The Maverick allows targets to be engaged at much greater ranges than the cannon, a safer proposition in the face of modern anti-aircraft systems. During Desert Storm, in the absence of dedicated forward-looking infrared (FLIR) cameras for night vision, the Maverick's infrared camera was used for night missions as a "poor man's FLIR".[53] Other weapons include cluster bombs and Hydra rocket pods.[54] Although the A-10 is equipped to carry laser-guided bombs, their use is relatively uncommon.[55] The A-10 has not been equipped with weapon control systems for accurate bombing as of 2000.[19] A-10s usually fly with an ALQ-131 ECM pod under one wing and two AIM-9 Sidewinder air-to-air missiles under the other wing for self-defense.[56]
Modernization
The A-10 Precision Engagement Modification Program will update 356 A-10/OA-10s to the A-10C variant with a new flight computer, new glass cockpit displays and controls, two new 5.5-inch (140 mm) color displays with moving map function and an integrated digital stores management system.[10][26]Other funded improvements to the A-10 fleet include a new data link, the ability to employ smart weapons such as the Joint Direct Attack Munition ("JDAM") and Wind Corrected Munitions Dispenser, and the ability to carry an integrated targeting pod such as the Northrop Grumman LITENING targeting pod or the Lockheed Martin Sniper XR Advanced Targeting Pod (ATP). Also included is the Remotely Operated Video Enhanced Receiver (ROVER) to provide sensor data to personnel on the ground.[25]
Colors and markings
Since the A-10 flies low to the ground and at subsonic speed, aircraft camouflage is important to make the aircraft more difficult to see. Many different types of paint schemes have been tried. These have included a "peanut scheme" of sand, yellow and field drab; black and white colors for winter operations and a tan, green and brown mixed pattern.[57]The two most common markings applied to the A-10 have been the European I woodland camouflage scheme and a two-tone gray scheme. The European woodland scheme was designed to minimize visibility from above, as the threat from hostile fighter aircraft was felt to outweigh that from ground-fire. It uses dark green, medium green and dark gray in order to blend in with the typical European forest terrain and was used from the 1980s to the early 1990s. Following the end of the Cold War, and based on experience during the 1991 Gulf War, the air-to-air threat was no longer seen to be as important as that from ground fire, and a new color scheme known as "Compass Ghost" was chosen to minimize visibility from below. This two-tone gray scheme has darker gray color on top, with the lighter gray on the underside of the aircraft, and started to be applied from the early 1990s.[58]
Many A-10s also featured a false canopy painted in dark gray on the underside of the aircraft, just behind the gun. This form of automimicry is an attempt to confuse the enemy as to aircraft attitude and maneuver direction.[59][60]
Operational history
Introduction
The first unit to receive the A-10 Thunderbolt II was the 355th Tactical Training Wing, based at Davis-Monthan Air Force Base, Arizona, in March 1976. The first unit to achieve full combat-readiness was the 354th Tactical Fighter Wing at Myrtle Beach AFB, South Carolina, in 1978. Deployments of A-10As followed at bases both at home and abroad, including England AFB, Louisiana; Eielson AFB, Alaska; Osan Air Base, South Korea; and RAF Bentwaters/RAF Woodbridge, England. The 81st TFW of RAF Bentwaters/RAF Woodbridge operated rotating detachments of A-10s at four bases in Germany known as Forward Operating Locations (FOLs): Leipheim, Sembach Air Base, Nörvenich, and Ahlhorn.[61]
A-10s were initially an unwelcome addition to many in the Air Force. Most pilots switching to the A-10 did not want to because fighter pilots traditionally favored speed and appearance.[62] In 1987, many A-10s were shifted to the forward air control (FAC) role and redesignated OA-10.[63] In the FAC role the OA-10 is typically equipped with up to six pods of 2.75 inch (70 mm) Hydra rockets, usually with smoke or white phosphorus warheads used for target marking. OA-10s are physically unchanged and remain fully combat capable despite the redesignation.[64]
Gulf War and Balkans
A-10s returned to the region as part of Operation Allied Force in Kosovo beginning in March 1999.[71] In March 1999, A-10s escorted and supported search and rescue helicopters in finding a downed F-117 pilot.[72] The A-10s were deployed to support search and rescue missions. But the Warthogs began to receive more ground attack missions as the days passed. The A-10's first successful attack in Operation Allied Force happened on 6 April 1999. A-10s remained until combat ended in late June 1999.[73]
Afghanistan, Iraq and Libya Wars
Operation Iraqi Freedom began on 20 March 2003. Sixty OA-10/A-10 aircraft took part in early combat there.[75] United States Air Forces Central issued Operation Iraqi Freedom: By the Numbers, a declassified report about the aerial campaign in the conflict on 30 April 2003. During that initial invasion of Iraq, A-10s had a mission capable rate of 85% in the war and fired 311,597 rounds of 30 mm ammunition. A single A-10 was shot down near Baghdad International Airport by Iraqi fire late in the campaign. The A-10 also flew 32 missions in which the aircraft dropped propaganda leaflets over Iraq.[76]
On 25 March 2010, an A-10 conducted the first flight of an aircraft with all engines powered by a biofuel blend. The flight, performed at Eglin Air Force Base, used a 1:1 blend of JP-8 and Camelina-based fuel.[79]
In March 2011, six A-10s were deployed as part of Operation Odyssey Dawn, the coalition intervention in Libya. They participated in attacks on Libyan ground forces there.[80][81]
Future retirement
The A-10 is scheduled to be in service with the USAF until 2028 and possibly later,[82] when it may be replaced by the Lockheed Martin F-35 Lightning II.[28] Critics have responded by saying that replacing the A-10 with the F-35 would be a "giant leap backwards" given the performance of the Warthog and the rising costs of the F-35 program.[83] In 2012 the Air Force concluded the F-35B cannot generate enough sorties to meet their needs, and so it will not replace the A-10.[84]The National Science Foundation has granted $11m to modify an A-10 to perform weather research for CIRPAS at the US Naval Postgraduate School,[85][86] to continue the effort after[87] the T-28 that was retired in 2005.[88][87]
In early 2012, the USAF proposed to disband five A-10 squadrons in its budget request, in order to lessen cuts to more versatile aircraft in a smaller future fleet.[89]
Variants
- YA-10A
- Pre-production variant. 12 were built.[90]
- A-10A
- Single-seat close air support, ground-attack version.
- OA-10A
- A-10As used for airborne forward air control.
- YA-10B Night/Adverse Weather
- Two-seat experimental prototype, for work at night and in bad weather. The one YA-10B prototype was converted from an A-10A.[91]
- A-10C
- A-10As updated under the incremental Precision Engagement (PE) program.[25]
- A-10PCAS
- Proposed unmanned version being developed by Raytheon and Aurora Flight Sciences as part of DARPA's Persistent Close Air Support program.[92]
Operators
The Air Force operates multiple A-10/OA-10 Active, National Guard, and Reserve squadrons.
- United States Air Force
- 23d Wing: Moody Air Force Base, Georgia
- 51st Fighter Wing: Osan Air Base, South Korea
- 52d Fighter Wing: Spangdahlem Air Base, Germany
- 53d Wing: Eglin Air Force Base, Florida
- 57th Wing: Nellis AFB, Nevada
- 355th Wing: Davis-Monthan Air Force Base, Arizona
- 127th Wing at Selfridge ANGB, Michigan (Transitioned from F-16s to A-10s due to BRAC 2005)
- 122nd Fighter Wing (formerly 358th Fighter Group): Fort Wayne, Indiana
- 124th Fighter Wing: Boise Air Terminal, Idaho
- 175th Wing: Warfield ANGB, Martin State Airport, Maryland
- 188th Fighter Wing: Fort Smith, Arkansas (Transitioned from F-16s to A-10s due to BRAC 2005)
- 442d Fighter Wing: Whiteman Air Force Base, Missouri
- 76th Fighter Squadron (Geographically Separated Unit (GSU) at Moody AFB, Georgia)
- 303d Fighter Squadron
- 45th Fighter Squadron (GSU at Davis-Monthan Air Force Base, Arizona)
- 917th Fighter Group: Barksdale Air Force Base, Louisiana (GSU of 442 FW)
Former operators
- United States Air Force
- 81st Tactical Fighter Wing: RAF Bentwaters/RAF Woodbridge operated A-10s from June 1979 to April 1993.
- 10th Tactical Fighter Wing: RAF Alconbury operated A-10s during 1988–1992
- 354th Tactical Fighter Wing: Myrtle Beach AFB operated A-10s during 1977–1993
- 926th Fighter Wing: NAS JRB New Orleans, Louisiana
- 706th Fighter Squadron (wing and squadron deactivated 2007 due to BRAC 2005)
- 111th Fighter Wing: NAS JRB Willow Grove/Willow Grove ARS, Pennsylvania (unit lost last four aircraft June 2010 as per 2005 BRAC)
- 103d Fighter Squadron
- 103d Fighter Wing: Bradley ANGB, Connecticut (BRAC 2005 removed A-10 aircraft, redesignated as 103d Airlift Wing and given C-21 in 2007)
- 118th Fighter Squadron (redesignated 118th Airlift Squadron per BRAC 2005)
- 104th Fighter Wing: Barnes ANGB, Massachusetts (BRAC 2005 saw unit transition from A-10 to F-15C in 2007)
- 131st Fighter Squadron
- 174th Fighter Wing: Hancock Field, New York (Transitioned to F-16As in 1988)
- 138th Fighter Squadron
- 110th Fighter Fighter Wing, 172nd Fighter Squadron Battle Creek Michigan (Operated A-10A and A-10Cs 1991–2008 BRAC 2005 changed unit to C-21s 2008–2012. C-27J will be gained in 2012.)
Specifications (A-10A)
 
|
- Crew: 1
- Length: 53 ft 4 in (16.26 m)
- Wingspan: 57 ft 6 in (17.53 m)
- Height: 14 ft 8 in (4.47 m)
- Wing area: 506 ft² (47.0 m²)
- Airfoil: NACA 6716 root, NACA 6713 tip
- Empty weight: 24,959 lb (11,321 kg)
- Loaded weight: 30,384 lb (13,782 kg) On CAS mission: 47,094 lb (21,361 kg)
On anti-armor mission: 42,071 lb (19,083 kg) - Max. takeoff weight: 50,000 lb (23,000 kg)
- Powerplant: 2 × General Electric TF34-GE-100A turbofans, 9,065 lbf (40.32 kN) each
- Never exceed speed: 450 knots (518 mph,[95] 833 km/h) at 5,000 ft (1,500 m) with 18 Mk 82 bombs[96]
- Maximum speed: 381 knots (439 mph, 706 km/h) at sea level, clean[95]
- Cruise speed: 300 knots (340 mph, 560 km/h)
- Stall speed: 120 knots (138 mph, 220 km/h) [97]
- Combat radius:
- On CAS mission: 250 nmi (288 mi, 460 km) at 1.88 hour single-engine loiter at 5,000 ft (1,500 m), 10 min combat
- On anti-armor mission: 252 nmi (290 mi, 467 km), 40 nm (45 mi, 75 km)) sea-level penetration and exit, 30 min combat
- Ferry range: 2,240 nmi (2,580 mi, 4,150 km) with 50 knot (55 mph, 90 km/h) headwinds, 20 minutes reserve
- Service ceiling: 45,000 ft (13,700 m)
- Rate of climb: 6,000 ft/min (30 m/s)
- Wing loading: 99 lb/ft² (482 kg/m²)
- Thrust/weight: 0.36
- Guns: 1× 30 mm (1.18 in) GAU-8/A Avenger gatling cannon with 1,174 rounds
- Hardpoints:
11 (8× under-wing and 3× under-fuselage pylon stations) with a capacity
of 16,000 lb (7,260 kg) and provisions to carry combinations of:
- Rockets:
- 4× LAU-61/LAU-68 rocket pods (each with 19× / 7× Hydra 70 mm rockets, respectively)
- 4× LAU-5003 rocket pods (each with 19× CRV7 70 mm rockets)
- 6× LAU-10 rocket pods (each with 4× 127 mm (5.0 in) Zuni rockets)
- Missiles:
- 2× AIM-9 Sidewinders air-to-air missiles for self-defense
- 6× AGM-65 Maverick air-to-surface missiles
- Bombs:
- Mark 80 series of unguided iron bombs or
- Mk 77 incendiary bombs or
- BLU-1, BLU-27/B Rockeye II, Mk20, BL-755[98] and CBU-52/58/71/87/89/97 cluster bombs or
- Paveway series of Laser-guided bombs or
- Joint Direct Attack Munition (A-10C)[99] or
- Wind Corrected Munitions Dispenser (A-10C)
- Other:
- SUU-42A/A Flares/Infrared decoys and chaff dispenser pod or
- AN/ALQ-131 or AN/ALQ-184 ECM pods or
- Lockheed Martin Sniper XR or LITENING targeting pods (A-10C) or
- 2× 600 US gallon Sargent Fletcher drop tanks for increased range/loitering time.
- Rockets:
- AN/AAS-35(V) Pave Penny laser tracker pod[100] (mounted beneath right side of cockpit) for use with Paveway LGBs
- Head-up display (HUD) for improved technical flying and air-to-ground support.[101]
Notable appearances in media
Main article: A-10 Thunderbolt II in fiction
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