A-10 Thunderbolt II: attack aircraft built around aircraft cannon
The A-10 Thunderbolt II is an American single-seat twin-engine attack aircraft, created by Fairchild-Republic. His main specialization was the fight against ground targets, primarily with tanks and other enemy armored vehicles. This aircraft is familiar to almost all fans aviation and has a recognizable and well-remembered appearance. It received its name Thunderbolt II in honor of the famous American fighter-bomber of the Second World War P-47 Thunderbolt.
The A-10 Thunderbolt II attack aircraft was the first American Air Force aircraft specially designed for direct air support of ground forces on the battlefield. This is a fairly simple, robust and efficient jet aircraft. After being adopted by the US Air Force, the car was treated as a “ugly duckling” for a long time, which was due to both its limited use and not the most common appearance for which the aircraft even received the unofficial nickname Warthog - warthog. The car was criticized for quite a long time, the American Air Force even thought about getting rid of it in favor of the A-16, a modification of the F-16 fighter, but the unexpectedly successful combat use of the A-10 Thunderbolt II during the first Gulf War put an end to the debate the fate of attack aircraft.
The A-10 Thunderbolt II attack aircraft was the first American Air Force aircraft specially designed for direct air support of ground forces on the battlefield. This is a fairly simple, robust and efficient jet aircraft. After being adopted by the US Air Force, the car was treated as a “ugly duckling” for a long time, which was due to both its limited use and not the most common appearance for which the aircraft even received the unofficial nickname Warthog - warthog. The car was criticized for quite a long time, the American Air Force even thought about getting rid of it in favor of the A-16, a modification of the F-16 fighter, but the unexpectedly successful combat use of the A-10 Thunderbolt II during the first Gulf War put an end to the debate the fate of attack aircraft.
It was during the Gulf War in 1991 that the combat debut of the A-10 attack aircraft took place. In total, 144 aircraft of this type took part in the operation, they made a total of 8100 sorties, losing 7 machines (on average, one attack aircraft lost on 1350 sorties). To the surprise of many outside observers, the seemingly unsound subsonic aircraft was able to become one of the “heroes” of this war, along with the stealth F-117 stealth aircraft and the F-15 fighter. According to the US military, Thunderbolts were able to destroy more than a thousand Iraqi tanks (more than any other aircraft of the US Air Force), up to two thousand units of other military equipment and 1200 artillery systems of all kinds.
History This machine began at a time when the US Air Force began to suffer significant losses from the Soviet air defense systems supplied to Vietnam - small-caliber anti-aircraft artillery and large-caliber machine guns. Under such conditions, it became increasingly difficult for them to support ground troops. Imagining what might happen if American planes are opposed not by a weak Vietnamese air defense system, but by Soviet anti-aircraft gunners or air defenses of the countries of the socialist bloc, the American military set off to create an armored attack aircraft. The design and construction stage of prototypes was completed relatively quickly and already 10 May 1972, the first attack aircraft of the Fairchild-Republic company A-10 rose into the sky, only 20 days ahead of the competitor Northrop A-9.
History This machine began at a time when the US Air Force began to suffer significant losses from the Soviet air defense systems supplied to Vietnam - small-caliber anti-aircraft artillery and large-caliber machine guns. Under such conditions, it became increasingly difficult for them to support ground troops. Imagining what might happen if American planes are opposed not by a weak Vietnamese air defense system, but by Soviet anti-aircraft gunners or air defenses of the countries of the socialist bloc, the American military set off to create an armored attack aircraft. The design and construction stage of prototypes was completed relatively quickly and already 10 May 1972, the first attack aircraft of the Fairchild-Republic company A-10 rose into the sky, only 20 days ahead of the competitor Northrop A-9.
The aircraft was produced serially from 1975 to 1984 a year, all 715 aircraft were assembled, the cost of one machine was 18,8 million dollars. The plane still remains in service with the US Air Force. On 2015, the 283 of the A-10C aircraft remained in service for the year. A-10C is an updated attack aircraft model equipped with modern digital equipment capable of carrying the entire set of high-precision weapons with a laser targeting system. The first A-10C attack aircraft entered service with the US Air Force in 2006 year.
Attack aircraft design
Structurally, the single-seat attack aircraft A-10 Thunderbolt II is a low-wing aircraft with a trapezoidal wing and two-tail vertical tail. The fuselage of a combat aircraft of a simple semi-monocoque type was made mainly of aluminum alloys, which were highly resistant to defoliants (a mixture of defoliants and herbicides was the infamous Agent Orange), widely used by Americans in Vietnam. The fuselage of the aircraft is distinguished by a rather high survivability: it should not have collapsed when two diametrically opposed side members were damaged, as well as two adjacent skin panels.
The three-lower low wing consisted of a rectangular center section, in which were the fuel tanks, and two trapezoidal consoles. The simplicity of the attack wing design was achieved using a large number of straight spars, identical ribs and plating, which was produced by stamping. In the places of changing the thickness of the skin along the wing span, the designers have foreseen the use of direct joints with overlap. The wing tips of the A-10 Thunderbolt II were bent downward, which increased the cruising range by 8%. The wing itself was distinguished by a large relative curvature and thickness, which ensured the optimum lift value at low flight speeds.
The pilot and critical control systems of the attack aircraft are reliably protected by 1.5 inch titanium armor, which is able to withstand the hit of 37-mm projectiles. At the same time, the pilot’s armored cabin was made in the form of a “bath” assembled with titanium bronelista screws. The bulletproof glass of the cockpit is able to withstand a 23-mm projectile hit by such a ZSU as the Shilka.
At the ends of the central part of the wing of the aircraft, fairings were installed to accommodate the main landing gear retractable forward. Niches of the fairings of the racks after their cleaning are not closed by the guards, so the wheels of the chassis slightly protrude outward, which makes an emergency landing of the attack aircraft safer. The tail of the aircraft was designed by designers so that, with the loss of one keel or even one of the halves of the stabilizer A-10 Thunderbolt II could continue its flight.
The pilot and critical control systems of the attack aircraft are reliably protected by 1.5 inch titanium armor, which is able to withstand the hit of 37-mm projectiles. At the same time, the pilot’s armored cabin was made in the form of a “bath” assembled with titanium bronelista screws. The bulletproof glass of the cockpit is able to withstand a 23-mm projectile hit by such a ZSU as the Shilka.
At the ends of the central part of the wing of the aircraft, fairings were installed to accommodate the main landing gear retractable forward. Niches of the fairings of the racks after their cleaning are not closed by the guards, so the wheels of the chassis slightly protrude outward, which makes an emergency landing of the attack aircraft safer. The tail of the aircraft was designed by designers so that, with the loss of one keel or even one of the halves of the stabilizer A-10 Thunderbolt II could continue its flight.
New and interesting for combat aircraft was the installation of the engines, which were placed in separate gondolas on the sides of the tail section of the attack aircraft. The advantages of such a layout could include reducing the radar and thermal visibility of engines, reducing the likelihood of foreign objects from the runway and gunpowder gases entering the air intake when firing from an artillery installation. Also, a similar layout of the power plant allowed servicing the attack aircraft and armament suspensions with the engines running and provided convenience during its operation and replacement. In addition, the central part of the A-10 attack aircraft remained free to accommodate fuel tanks near the aircraft's center of gravity, which made it possible to dispense with the fuel transfer system to provide the necessary centering of the aircraft.
The advantage of this arrangement was the increased survivability of the attack aircraft. Confirmation of this was obtained in combat conditions. In 1999, from air bases located in Italy, the A-10 Thunderbolt II attack aircraft took part in a NATO military operation against the Federal Republic of Yugoslavia. As part of this operation, the US military did not recognize a single loss of A-10 attack aircraft. At the same time, 2 in May 1999, at the airport in Skopje (Macedonia), was made an emergency landing by one of the attack aircraft of this type. The aircraft sat on one engine, the second engine was completely shot off, and later it was shown on Yugoslav television.
The advantage of this arrangement was the increased survivability of the attack aircraft. Confirmation of this was obtained in combat conditions. In 1999, from air bases located in Italy, the A-10 Thunderbolt II attack aircraft took part in a NATO military operation against the Federal Republic of Yugoslavia. As part of this operation, the US military did not recognize a single loss of A-10 attack aircraft. At the same time, 2 in May 1999, at the airport in Skopje (Macedonia), was made an emergency landing by one of the attack aircraft of this type. The aircraft sat on one engine, the second engine was completely shot off, and later it was shown on Yugoslav television.
The high maneuverability of the attack aircraft at low altitudes gave the car a good chance of dodging missiles and attacking enemy fighters. Good maneuverability combined with a cockpit view and relatively low airspeed allowed the aircraft to hit even relatively small targets from one approach. An artillery system fired at targets such as a tank from a height of 100-150 meters from a distance of 1800 meters; unarmored targets could be fired from a distance of 3000-3600 meters.
The gun around which the aircraft was built
In 1970, the US military finally decided on the main artillery caliber for the new attack aircraft. As artillery weapons, it was decided to use the heavy-duty 30-mm seven-barreled gun GAU-8 / A Avenger (Avenger) of General Electric. The initial velocity of shells fired from it is 1067 m / s, and the rate of fire reaches 4000 rounds per minute. After the 75-mm artillery gun, which was installed on American aircraft during the Second World War, the GAU-8 / A became the most powerful aviation artillery system developed in the United States. When it was created, the designers took into account the successful experience of using Israeli military aircraft 30-mm DEFA cannons against Arab armored vehicles during the 1967 war of the year.
The 30-mm seven-barreled air gun of the Gatling scheme with a rotating block of barrels was specially created for the A-10 Thunderbolt II attack aircraft, becoming its calling card. The GAU-8 / A is one of the most powerful aircraft guns of this caliber in the world. The weight of the gun is 281 kg, the weight of the entire gun installation - 1830 kg (including the ammunition supply system, a drum with full ammunition). The diameter of the cartridge box is 86 cm, length - 182 cm.
During the tests, which were conducted at the Nellis air base, located in Nevada, 24 launched an A-10A attack aircraft on 15 target types, 7 of which were destroyed, and the rest were incapacitated. The pilots fired from a cannon with a pace of 2100 vist / min and 4200 vist / min at a distance of 1800 meters. It should be noted that these tests were conducted in field conditions. The pilots studied the terrain in detail, the armored vehicles were still, the weather was perfect. And, of course, there was no opposition to the pilots of attack aircraft — neither passive (setting up smoke screens), nor, especially, fire.
During the tests, which were conducted at the Nellis air base, located in Nevada, 24 launched an A-10A attack aircraft on 15 target types, 7 of which were destroyed, and the rest were incapacitated. The pilots fired from a cannon with a pace of 2100 vist / min and 4200 vist / min at a distance of 1800 meters. It should be noted that these tests were conducted in field conditions. The pilots studied the terrain in detail, the armored vehicles were still, the weather was perfect. And, of course, there was no opposition to the pilots of attack aircraft — neither passive (setting up smoke screens), nor, especially, fire.
GAU-8 / A next to the car Volkswagen Beetle
The 30-mm GAU-8 / A aircraft cannon is located along the longitudinal axis of the attack aircraft, it is offset to its left side by an 0,3 meter. The gun works on the principle of Gatling, has a hydraulic external drive and a spineless ammunition supply system. A used drum magazine holds 1350 cartridges. The sleeve of the used cartridges was made not of steel, but of aluminum, which made it possible to increase the ammunition load of the artillery unit by 30% for a given mass. 30-mm projectiles have plastic leading belts that help extend the life of the barrels. Initially, the gun’s firing rate could be switched from 2100 to 4200 shots per minute, but later the maximum rate of fire was limited to 3900 shots per minute. In practice, the duration of firing from GAU-8 / A is limited to one or two-second volleys, this is necessary to prevent overheating of barrels, overruns of projectiles, as well as to extend the service life of barrels. The break for cooling the artillery system is about a minute. The life of the barrel unit is 21 thousand shots. Each shooting cycle begins with the promotion of a block of trunks from two hydraulic actuators that are powered by the attacker's hydraulic system.
The shells-free feed system was chosen specifically to reduce the weight of the installation. The spent cartridges are not thrown out; the cartridges are assembled back into the drum in order not to damage the casing of the aircraft during firing. The ammunition supply system is similar to that on the M61 Vulcan, however, it has a more modern design, which effectively saves weight. The constructive perfection of the aviation artillery system GAU-8 / A Avenger can be judged by the value of such an important characteristic as the mass fraction of projectiles in the mass of the whole cannon installation. For GAU-8 / A, this value is 32% (for example, the М61А1 cannon has just 19%). Such indicators have been achieved through the introduction of aluminum sleeves instead of steel and brass.
The shells-free feed system was chosen specifically to reduce the weight of the installation. The spent cartridges are not thrown out; the cartridges are assembled back into the drum in order not to damage the casing of the aircraft during firing. The ammunition supply system is similar to that on the M61 Vulcan, however, it has a more modern design, which effectively saves weight. The constructive perfection of the aviation artillery system GAU-8 / A Avenger can be judged by the value of such an important characteristic as the mass fraction of projectiles in the mass of the whole cannon installation. For GAU-8 / A, this value is 32% (for example, the М61А1 cannon has just 19%). Such indicators have been achieved through the introduction of aluminum sleeves instead of steel and brass.
GAU-8 / A firing mode at the maximum allowed rate - 10 two-second bursts with minute air cooling between them. Already during the operation of the A-10 attack aircraft, it was found that during the firing of a seven-barreled air cannon, the powder gases are sucked into the attack aircraft engine, as a result of which unburned powder particles are deposited on the blades of the compressor and the engine fan. The accumulation of unburned powder particles after each 1000 shots are performed reduces the aircraft engine thrust by 1%. The overall reduction in thrust with engines has reached 10%, which increased the likelihood of stalling from the blades of the compressor and engines. In order for the engines not to stall when firing from an artillery installation, special ignition devices were built into them in 1981, which ignite unburned powder particles. As a result of these measures, the problem of the accumulation of particles of gunpowder was solved.
The artillery unit is powered by PGU-14 / B armor-piercing sub-caliber shells (425 projectile mass grams) and high-explosive fragmentation shells PGU-13 / B (grams 360 projectile mass). Standard Thunderbolt attack aircraft are 1100 30-mm projectiles in the following order - for one high-explosive fragmentation projectile PGU-13 / B there is an 4 armor-piercing projectile PGU-14 / B with a core of depleted uranium. Accuracy of the seven-barreled aviation 30-mm gun GAU-8 / A is characterized by the following indicators: 5 milliradian (mrad), 80% - this means that when shooting at 1220 meters 80% of all projectiles fall into a circle with 6,1 radius of meter. For example, for the M61 “Vulkan” air cannon, this indicator is 8 mrad.
The artillery unit is powered by PGU-14 / B armor-piercing sub-caliber shells (425 projectile mass grams) and high-explosive fragmentation shells PGU-13 / B (grams 360 projectile mass). Standard Thunderbolt attack aircraft are 1100 30-mm projectiles in the following order - for one high-explosive fragmentation projectile PGU-13 / B there is an 4 armor-piercing projectile PGU-14 / B with a core of depleted uranium. Accuracy of the seven-barreled aviation 30-mm gun GAU-8 / A is characterized by the following indicators: 5 milliradian (mrad), 80% - this means that when shooting at 1220 meters 80% of all projectiles fall into a circle with 6,1 radius of meter. For example, for the M61 “Vulkan” air cannon, this indicator is 8 mrad.
Flight performance of A-10 Thunderbolt II:
Overall dimensions: length - 16,25 m, height - 4,47 m, wing span - 17,53 m, wing area - 47 m2.
Empty weight - 11 321 kg.
Maximum take-off weight - 23 000 kg.
The power plant - 2 TRDD General Electric TF34-GE-100 kong 2x40,32.
The maximum allowable speed is 833 km / h.
Maximum ground speed is 706 km / h.
Cruising speed - 560 km / h.
Practical ceiling - 13 700 m.
Combat radius of action - 460 km.
Ferry range - 4150 km.
Armament:
Gun-gun: 30-mm seven-barreled gun GAU-8 / A Avenger, ammunition 1350 cartridges 30 x173 mm.
Suspension points: 11 armament suspension units (8 under the wing, 3 under the fuselage), maximum combat load 7260 kg.
Crew - 1 man.
Overall dimensions: length - 16,25 m, height - 4,47 m, wing span - 17,53 m, wing area - 47 m2.
Empty weight - 11 321 kg.
Maximum take-off weight - 23 000 kg.
The power plant - 2 TRDD General Electric TF34-GE-100 kong 2x40,32.
The maximum allowable speed is 833 km / h.
Maximum ground speed is 706 km / h.
Cruising speed - 560 km / h.
Practical ceiling - 13 700 m.
Combat radius of action - 460 km.
Ferry range - 4150 km.
Armament:
Gun-gun: 30-mm seven-barreled gun GAU-8 / A Avenger, ammunition 1350 cartridges 30 x173 mm.
Suspension points: 11 armament suspension units (8 under the wing, 3 under the fuselage), maximum combat load 7260 kg.
Crew - 1 man.
Information sources:
http://www.airwar.ru/weapon/guns/gau8a.html
http://www.anaga.ru/a-10-thundebolt-ii.html
http://shvp.livejournal.com/132878.html
http://pro-samolet.ru/blog-pro-samolet/534-twin-attack-a-10-thunderbolt
http://thechive.com/2016/08/25/the-plane-built-around-one-gun-42-hq-photos (фото)
http://www.airwar.ru/weapon/guns/gau8a.html
http://www.anaga.ru/a-10-thundebolt-ii.html
http://shvp.livejournal.com/132878.html
http://pro-samolet.ru/blog-pro-samolet/534-twin-attack-a-10-thunderbolt
http://thechive.com/2016/08/25/the-plane-built-around-one-gun-42-hq-photos (фото)
Information