All helicopters are sensitive to stress, and therefore the focus when choosing weapons for them invariably done on the weight of the helicopter. However, while multi-purpose helicopters needed weapons for the circular self-defense, attack helicopters must forward firing weapons that can destroy hardened targets from a safe distance removal and installation of movable cannon to fire less complex goals.
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If you take the easy part of the spectrum of weapons, guns are not commonly used on attack helicopters, although the helicopter Bell AH-1G Cobra began life at the front of the gondola Emerson Electric TAT-102A with the established six-barrel 7.62-mm GAU-2B / A Minigun from General Electric. Likewise attack helicopter Mi-24 was originally equipped Quadruple 12.7mm Yakushev-Borzova (Jac-12, 7) 9A624 in remotely controlled device.
Cannon almost universally replaced guns as weapons gondola. One of the few exceptions is the Eurocopter Tiger UHT of the German army, now he can carry automatic weapons only as fixedly secured containers with weapons.

In December 2012 helicopters Tiger UHT, standing armed German KHR36 helicopter regiment in Afghanistan were set containers FN Herstal HMP400, each with a 12.7-mm machine gun M3P and 400 cartridges. The container weighs 138 kg and has a rate of gun 1025 rounds per minute.

Modified by Eurocopter to standard Asgard-F (Afghanistan Stabilisation German Army Rapid Deployment - Full, rapid deployment of the German army to stabilize Afghanistan - Full), these helicopters Tiger also are armed with 19-charging missile launchers 70 mm rockets and guided missiles MBDA Hot.
Another attack helicopters, which still stands turret machine gun mount is Iranian Hesa ​​Shahed (Witness) 285. It is very light weight (1450 kg) single unit - modification Bell 206 JetRanger. Helicopter under the designation AH-85A armed with a single-12.7mm RMB in front of the turret, he reportedly is in limited use in the Air Force of the Iranian Revolutionary Guard.

Gun

Wipe guns guns as weapons helicopter has a rational explanation. America discovered in Vietnam, and later the Soviet Union in Afghanistan, which are installed on the helicopter guns easily "skirmish" with heavy automatic weapons land.

In the ground-air operations 7.62mm machine gun is only effective at a distance of about 500 meters and only against soft targets, such as personnel in open space. 12.7-mm machine gun firing range increases up to 1000 meters and can handle a broader range of goals. Gun (capable of firing high explosive ammunition) begins with a caliber of 20 mm, it is quite effective at distances up to 1700 meters and can destroy light armored vehicles.
One example of a 20-mm weapons for the attack helicopter is a gondola Nexter Systems THL20 with single-barrel gun 20M621. It is installed on the machines of the Romanian IAR-330L Puma, has also been selected for the Indian helicopter HAL Light Combat Helicopter (LCH). Another anterior ventral installation GI-2 from the South African company Denel Land Systems is designed to upgrade Mi-24 helicopters of the Algerian Air Force. GI-2 is also installed on the Denel Rooivalk (Kestrel). These guns are usually rate of 700 - 750 rounds per minute.

If a high rate (which, in general, it is not necessary for the shelling ground targets, but may be preferred when firing at aircraft and speedboats), in this case suitable gun with several trunks.

A typical example is the triple-20mm Gatling gun M197 from General Dynamics Armament and Technical Products, which can be fired with a rate of up to 1500 rounds / min and is set in a gondola on helicopter Bell AH-1J / W, a new helicopter AH-1Z, and on the AgustaWestland A129. One reason for choosing the helicopter A129 as the basis of the Turkish program Atak was excellent accuracy of his gun turret M197 installed in Oto Melara TM197B.

In developing the Mi-24 in the 80s in order to meet operational requirements in Afghanistan Mil primarily to replace the original Quadruple Jac-12 machine gun, 7 dvuhstvolnoy 23 mm GSh-23L on a movable turret. Was made of 25 Mi-24VP, but this helicopter scope gun GSH-23L is not limited, it is installed in a container with 250 cannon rounds (UPK-23-250) under the wings of various Russian helicopters.

In the production of the Mi-24P from the front turret was abandoned in favor dvuhstvolnoy 30mm cannon GSH-30 attached to the right side of the fuselage. However, the ventral gondola GS-23 (NPPU-23) returned to the export version of the Mi-35M, were armed with Brazil and Venezuela.
With a few notable exceptions (Series AH-1 and A129) in most parts of attack helicopters mounted 30mm cannon. The leader was a helicopter Boeing AH-64 Apache gun with chain drive Alliant Techsystems (ATK) M230 Chain Gun in a gondola beneath the front cabin.

Another example is the Eurocopter Tiger ARH / HAD / HAP gun Nexter Systems 30M781 in ventral turret THL30. As was said earlier helicopter Tiger UHT of the German Army has no turret, but covers the installation recoilless gun turret 30 mm Rheimetall / Mauser RMK30 (Rueckstossfreie Maschinenkanone 30) in a flexible suspension, leading fire caseless ammunition with a rate of 300 rounds / min.

In the further development of the Soviet Mi-24 helicopter with BMP-2 was borrowed proven single-barreled 30-mm gun 2A42 dual feed. Firing guns is selectable between 200 and 550 shots per minute.

In the case of the Mi-28N 2A42 cannon mounted in a gondola NPPU-28N under the front cabin, but the helicopter Ka-50/52 this gun trunnion mounted in the right side of the fuselage and can be rotated vertically by 40.5 degrees.
The above guns are efficient means of dealing with a wide range of targets set at the wide angle from the axis of the aircraft. However, helicopter gun easily "plays with" modern air defense systems. For example, the widely used Quadruple 23-mm self-propelled anti-aircraft gun ZSU-23, leading to a fire at a speed of up to 4000 rounds / min, has actual slant range of 2,000 meters. While MANPADS have a maximum range of 4000 - 6500 meters.

Rockets air inlet may in turn take precedence over ground range automatic weapons. The most common Western rockets are 68 mm SNEB from Thales / TDA Armements and 2.75 dyuym/70-mm Hydra-70 from General Dynamics Armament and Technical Products, a rocket from the FZ90 and Forges de Zeebrugge rocket CRV7 of Magellan Aerospace.
Hydra-70 rocket is a modification FFAR (Folding-Fin Aircraft Rocket - Rocket with folding stabilizers) which was developed in the late 40s as unguided missiles "air-air", mainly in order to quickly and reliably hit a Soviet bomber carrying atomic bomb. She served as a temporary means until until entered service such guided missiles, such as, AIM-7.
Modern Hydra-70 is made with nine different warheads, including M151 (4,5 kg high explosive), M229 (7,7 kg high explosive) and M255A1 (with shrapnel), plus options smokescreen and practical lighting. Over four million Hydra-70 rockets were produced by GDATP 1994. It is charged in the 7 - and 19-pipe installation.
alleged that the Canadian missile CRV7 has superior performance with a valid range of up to 8000 meters. Over 800,000 of these missiles were produced for 13 countries
Russian 57mm rocket-5 currently displaced 80-mm rocket S-8, which weighs 11.1 - 15.2 kg and is mounted on a helicopter in the 20-tube launcher B8V20-A. It develops a maximum peak speed of 1.8 Mach and has a maximum range of 4,500 meters. C-8KOM has armor-piercing warhead cumulative, and the C-8BM designed to engage personnel in fortifications.

The Mi-28 can also carry two launchers Block B-13L1, each with five 122-mm rockets S-13, which are practically the most powerful rockets to shoot from helicopters. C-13T 75 kg has a tandem warhead capable of penetrating reinforced concrete one meter or six meters of soil. 68 kg C-13OF has high-explosive fragmentation warhead, which creates a cloud of 450 diamond-shaped elements 25 - 30 grams.

Mi-28N can carry two 240 mm rockets S-24B weighing 232 kg. It may be noted that the Russian attack helicopters used bombs weighing from 50 to 500 kg and universal container of small loads KMGU-2 for dropping submunitions.

It should be noted that due to the special nature of its missiles with laser guidance will be addressed in future surveys. They developed relatively recently and are intended in particular to ensure effective new weapons universal light helicopters, which are significantly cheaper to operate compared with specialized attack helicopters.
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One example of a 20-mm weapons for the attack helicopter is a gondola Nexter Systems THL20 with single-barrel gun 20M621. It is installed on the machines of the Romanian IAR-330L Puma, has also been selected for the Indian helicopter HAL Light Combat Helicopter (LCH). Another anterior ventral installation GI-2 from the South African company Denel Land Systems is designed to upgrade Mi-24 helicopters of the Algerian Air Force. GI-2 is also installed on the Denel Rooivalk (Kestrel). These guns are usually rate of 700 - 750 rounds per minute.

If a high rate (which, in general, it is not necessary for the shelling ground targets, but may be preferred when firing at aircraft and speedboats), in this case suitable gun with several trunks.

A typical example is the triple-20mm Gatling gun M197 from General Dynamics Armament and Technical Products, which can be fired with a rate of up to 1500 rounds / min and is set in a gondola on helicopter Bell AH-1J / W, a new helicopter AH-1Z, and on the AgustaWestland A129. One reason for choosing the helicopter A129 as the basis of the Turkish program Atak was excellent accuracy of his gun turret M197 installed in Oto Melara TM197B.

In developing the Mi-24 in the 80s in order to meet operational requirements in Afghanistan Mil primarily to replace the original Quadruple Jac-12 machine gun, 7 dvuhstvolnoy 23 mm GSh-23L on a movable turret. Was made of 25 Mi-24VP, but this helicopter scope gun GSH-23L is not limited, it is installed in a container with 250 cannon rounds (UPK-23-250) under the wings of various Russian helicopters.

In the production of the Mi-24P from the front turret was abandoned in favor dvuhstvolnoy 30mm cannon GSH-30 attached to the right side of the fuselage. However, the ventral gondola GS-23 (NPPU-23) returned to the export version of the Mi-35M, were armed with Brazil and Venezuela.