U . S . Helicopter Armament Subsystems The United States military has developed a number of Helicopter Armament Subsystems since the early 1960s . These systems are used for offensive and defensive purposes and make use of a wide variety of weapon types including , but not limited to machine gun s , grenade launcher s , autocannon , and rocket s . Various systems are still in use , though many have become obsolete . Introduction . The helicopter itself has added much to the modern battlefield , changing land warfare tactics across the board . Transportation , with the ability to rapidly deploy or evacuate forces or casualties has changed huge aspects of post - modern warfare . The helicopter as an armed weapon has also added a whole new dimension to the battlefield . Although one of the first armies to experiment with helicopters , the United States Army was slow to fully explore the possibilities of armed helicopters . Experiments between the Korean War and US involvement in South East Asia were small and fairly simple . Learning much from these involvements the US decided to look further into the idea of air mobile tactics , and subsequently armed helicopters , though an armed helicopter had been proposed and rejected in the early 1940s . By the time the UTTHCO ( Utility Tactical Transport Helicopter Company ) was deployed to Vietnam in 1962 , the US had started experimenting more with the idea of arming helicopters both for defensive and offensive purposes . UTTHCO was an expeditionary unit , deployed to Vietnam to assist the South Vietnamese Army and to provide on the ground testing for new air mobile theory . Weapon systems used by UTTHCO were often crude and made from field expedient parts and weapons . By 1965 , the United States had deployed a truly Air Mobile unit , the 1 / 7th Cavalry , which began to use more standardized armament systems . Throughout US involvement in Vietnam the US Army , US Marine Corps , and US Air Force would develop and utilize a number of armament systems designed for a variety of helicopters , and would pave the way for more dedicated attack helicopters . With the arrival of dedicated gunship helicopters such as the AH - 1 Cobra and later the AH - 64 Apache , armament subsystems for non - specific types would begin to drop off , with mostly defensive armament packages remaining . Such armament packages , giving decidedly heavy armament to small or primarily transport helicopters , have become popular among second and third world countries who lack the funds for dedicated attack helicopters . Most of the systems bear some resemblance to the plethora of US systems that follow in this entry . Explanation of format . As is immediately apparent the US Military and Defense Industry have designed and produced a wide array of helicopter systems fitting into this article . For clarity it seems wise to note how entries are titled and separated . The basic format is that entries will fit into one of three categories : In certain cases a manufacturer ' s designation or popular name is inserted into the entry title for clarity in instances where one may come across either term with some regularity , or where information is available . Also , instances of " Offensive Armament " or " Defensive Armament " might also be included where appropriate for systems that do not readily fall into one of the aforementioned categories , namely field modifications and test kits with no popular name . The M3 , sometimes referred to as " Aerial Rocket Artillery " or ARA , consisted of two 2 . 75 " 24 - Tube rocket launchers , one on either side of the aircraft , along with a Mk 8 sight . The launchers fired in pairs , one from each side to prevent the aircraft from becoming off balance . M3 systems were attached to the helicopter using Bell designed stores racks . The only difference between the XM3 and XM3E1 was that the launch tubes on the E1 were 4 " longer . The XM3E1 was standardized as the M3 . Armament sub - systems for transport and utility Helicopters . UH - 1 Iroquois . A subvariant of the M3 system was developed in 1964 by the US Army Limited War Laboratory that allowed equipped helicopters to produce a protective smoke screen . Called the Troop Landing Smoke Screen ( TLSS ) , the system used modified M3 launch racks to dispense M8 smoke grenades . This system was later tested using M6 and M7 riot control grenades . The XM5 / M5 system consists of a nose turret for a single M75 40mm grenade launcher . The mount was fully flexible and controlled by the pilot via a hand controlled sight electronically linked to the turret . The system either provided 150 or 302 rounds of ammunition . NOTE : This system was also part of the armament kit for the ACH - 47A discussed later in this article . The M6 system was one of the first systems to make use of the XM156 / M156 universal mount , providing two M60C 7 . 62x51mm machine guns on either side of the helicopter . This system would later be expanded upon , but initially gave the UH - 1 increased firepower and an improved offensive system over the skid mounts originally used . The various development stages of the M6 system mainly had to do with the " station " to which the M156 mount was attached . The position of the XM6 is not stated , but the XM6E2 was fitted to " station 69 " ( likely forward of the main cabin ) and the XM6E3 was fitted to " station 136 . " Since the XM6E3 was standardized as the M6 , " station 136 " is assumed to be the aft of main cabin position that would become standard for M156 based systems . Some M6 systems were coupled the four guns with four MA - 2 / A 2 . 75 " 2 - Tube rocket launchers on each side of the aircraft , giving an even greater punch . This arrangement was later supplanted by the XM16 / M16 system . A variant of the XM6 / M6 system , the XM9 substitutes the four M60C 7 . 62x51mm machine guns with two M75 grenade launchers , one on either side of the aircraft . Both of these armament systems were designed to allow the UH - 1 to fire the AGM - 22 missile . Sources claim that the XM11 provided an XM70 sight and support racks for 6 missiles , three on each side of the aircraft . However , US Army FM 1 - 40 says that the XM11 designation was unassigned . The M22 was an improvement providing a more specific sight , the XM58 , and using the XM156 universal mount . The M22 also provided for a total of 6 missiles , three on each side of the aircraft . It is important to note as well that that the XM11 is associated with the standard SS . 11 missiles ( AGM - 22A ) , while the XM22 / M22 system was designed around the US upgraded AGM - 22B missiles . The Maxwell System was a hybrid system designed by Warrant Office Robert Maxwell as a field modification . Maxwell ' s unit had been sent both the M3 and XM11 systems , and he noticed that often aircraft with the M3 system returned after only firing half or less than half of their total rocket load . By removing one or two banks of rockets ( and reducing the total carried to 12 or 18 total rockets versus 24 ) and adding a single launching mount for an AGM - 22 missile he effectively gave the aircraft both suppression and point attack capabilities . The general lack of point targets in South East Asia meant that SS . 11 / AGM - 22 missile saw very limited use in general . The XM16 / M16 system mated the previous M6 with either two M157 or two M158 2 . 75 " 7 - Tube rocket launchers utilizing the M156 Universal Mount . Sighting was accomplished by using the M60 series reflex sight . The combined weight and aircraft limitations meant that only seven - tube launchers could be used . The XM17 utilized " Kellet pylons " to mount two XM159 2 . 75 " rocket launchers , one on each side of the aircraft . A further variation on what had essentially become a basic system , the XM21 / M21 subsystem replaced the XM16 / M16 ' s four M60Cs with two M134 7 . 62x51mm Miniguns . The M23 system provides a pintle mount at both main cabin doors for an M60D 7 . 62x51mm machine gun , with the weapon feeding from either a standard ammunition box or a larger purpose built box connected to the mount . The M23 is specifically designed for long fuselage UH - 1s ( UH - 1D / H / N ) . With the development of the BGM - 71 TOW missile Hughes had been given the contract to develop a launching system for the UH - 1 . By 1968 development had shifted over to development of a system for the AH - 56 helicopter which was eventually canceled . The XM26 provided two 3 - Tube launchers on either side of the aircraft , as well as , the necessary sighting equipment . While the XM26 was more of a test platform , the two prototypes were deployed operationally as an emergency measure in South Vietnam to counter the Easter Invasion in 1972 . The XM29 was an experimental door pintle for the main cabin doors of short fuselage UH - 1s ( at the time the UH - 1B / C ) , for an M60D 7 . 62x51mm machine gun . The problem with this system was that it could not be used in conjunction with external armament subsystems . Far more common on such helicopters , including the later UH - 1F / P / M specifically , was the Sagami Mount , a skeleton frame mount that swung out from a fixed position at the rear of the cabin . This mount was designed for the M60D , but in certain instances , primarily by the US Navy Seawolves , dual M60s , M2HB machine guns or M134 Miniguns were fitted . Sources debate the origin of the " Sagami " name , with it being attributed to the soldier responsible for its creation , as well as , to the name of the US facility on Okinawa where it was developed . An experimental system , the XM30 provided fully flexible mounts using the XM156 / M156 universal mounts for two XM140 30mm cannons , with 600 rounds of ammunition per gun . Another attempt to up the firepower from existing systems , the XM31 provided two M24A1 20mm cannons in pods fitted to XM156 / M156 universal mounts each with 600 rounds of ammunition , and flexible in elevation only . XM50 is a designation for the combination of the XM5 / M5 and the XM21 / M21 armament subsystems , a common configuration used by US forces in South East Asia . A mine dispenser system for the UH - 1H helicopter , the M56 is composed of two SUU - 13D / A dispensers on the M156 Universal Mount , which is reinforced to handle the additional weight . A variation on the M23 , the XM59 / M59 was modified to accept either an XM213 / M213 . 50 caliber machine gun or an XM175 40mm grenade launcher in addition to being able to mount the M60 . This armament subsystem provides door mounts for long fuselage UH - 1s ( UH - 1D / H / N ) for two M134 7 . 62x51mm Miniguns . The USAF also used this system on their short fuselage UH - 1F / P helicopters . These weapons are equipped with chutes connected to their ejection ports that directs spent cases and links away from the aircraft . The XM93E1 is a variation on the system that allows both guns to be trained forward and remotely fired by the pilot using the M60 series of reflex sights . NOTE : The USAF was the primary user of this system and often combined it with two 7 - Tube 2 . 75 " rocket launchers of varying types on two independent support rack and pylon assemblies . A variant of the XM93 , the XM94 substitutes the M129 40mm grenade launcher for one or both of the door mounted M134 7 . 62x51mm Miniguns . Not technically an armament subsystem , the XM156 / M156 universal mount provided mounting supports and racks for a number of systems used on the UH - 1 series of helicopters . Similar to the US Army XM93 , this system type classified by the Air Force uses mounts similar to those used in the M23 system mounting two M134 7 . 62x51mm Miniguns at each of the main cabin doors of the UH - 1N helicopters . < ref name = " A / Annx Equipment Listing " > Parsch , Andreas . " Designation - Systems . net " 23 November 2006 A / Annx Equipment Listing . Access Date : 30 May 2007 < / ref > This system is likely suitable for other long - fuselage UH - 1 types . Referred to as the " Defensive Armament System " or DAS , this system is composed of two mounts for GAU - 15 / A and GAU - 16 / A . 50 caliber machine guns or GAU - 17 / A 7 . 62x51mm Miniguns , as well as , two BRU - 20 / A or BRU - 21 / A bomb racks for current 2 . 75 " rocket launchers . This system was also designed primarily for use with the UH - 1N helicopter ( and is in use with the US Marine Corps as well in this capacity ) , but is likely suitable for other long - fuselage UH - 1 types . A variant of the TK - 1 for the CH - 34 / UH - 34 helicopter , the TK - 2 ( Temporary Kit - 2 ) was developed by the USMC for their UH - 1E helicopter . The system provides the same four M60C 7 . 62x51mm machine guns as the TK - 1 , but adds two independent support rack and pylon assemblies to the system , for mounting an acceptable aircraft style armament . Typically these mounts were used for 7 - Tube 2 . 75 " rocket launchers of varying types , but were also seen tested with XM18 / M18 Minigun pods ( USAF SUU - 11 / A ) . Unique to USMC UH - 1E helicopters between April 1967 and 1972 was the use of the Emerson Electric TAT - 101 ( Tactical Armament Turret - 101 ) nose turret . The turret housed two M60 machine guns with 1000 rounds total , and had 100 degrees in azimuth left or right , plus 15 degrees of elevation and 45 degrees of depression . The slew - rate on the turret was 45 degrees per second . Jamming and the need for maintenance led to the turret ' s front fairing being left off to assist ground crews in quickly dealing with any problems , and these reasons combined in the USMC decision to drop the turrets from inventory entirely at the end of 1972 . A version of the TAT - 102 ( Tactical Armament Turret - 102 ) designed specifically for use on the HH - 3A helicopter , the TAT - 102C mounted a single M134 Minigun in a fully traversable turret ( for specifics see the information for the TAT - 102A in the AH - 1 Cobra entry ) . Two such turrets were mounted on sponsons , one on each side of the aircraft . The complexity and questionable performance in the environment led to them being removed in favor of more conventional door mounted weaponry . The defensive armament system for the USAF ' s H - 3E helicopters is described as standard to the HH - 3E , and capable of being fitted as required to the CH - 3E . The basic system comprises three M60 machine guns , one each at the forward door , the opposite emergency window , and the rear loading ramp . The forward two positions comprise pintle mounts on skate rails , while the rear loading ramp station comprises a pedestal mount on an armored floor plate . The floor plate slides on two tracks , forward and back , to and from its firing position at the edge of the ramp . Either the standard infantry M60 can be used , with standard 200 round ammunition boxes attached , or the M60D , feeding via flexible ammunition chutes from 750 round boxes fixed to the floor ( or to the armored floor plate for the rear loading ramp position ) . Described as a system comprising of four forward firing M60 machine guns similar to the later M6 series for the UH - 1 helicopter . Not standardized . Experiments were done using CH - 21s with both fixed forward M2HB . 50 caliber machine guns and forward firing rocket launchers . Neither system was standardized , but both paved the way for similar systems on later helicopter types . UTTHCO deployed with a number of CH - 21 ' s , and experimented with field expidient bars mated to the cargo doors , fitted with M37C . 30 - 06 machine guns and feed from boxes mounted on top of the weapon . CH - 21 Shawnee . NOTE : It would appear that similar mounts were fabricated for use with early UH - 1s as well . Described simply as a " 2 . 75 - inch rocket launcher subsystem for the CH - 34 , " there is no information as to how many rockets the XM4 was capable of launching . For more information on the M6 Series see the UH - 1 entry in this article . The XM6E1 was a variation of the XM6 for use with the CH - 34 helicopter . UH - 34 / CH - 34 Choctaw / Seahorse . A USMC weapon system to provide H - 34 helicopters with offensive armament , the TK - 1 ( Temporary Kit - 1 ) featured two M60C 7 . 62x51mm machine guns , fixed forward on the right side of the aircraft , with ammunition fed out from boxes inside the aircraft . Also attached to these assemblies were two pylons , fitted with 19 - shot 2 . 75 - inch rocket launchers . Aircraft equipped with the TK - 1 were sometimes referred to as " Stingers . " Both the US Army and the USMC developed pintle mounts for use in the main cargo door and opposite window , mounting a single infantry type M60 7 . 62x51mm machine gun ( sometimes referred to as " M60A " ) , allowing the crew chief to fire the weapon while seated on the opposite side . The USMC tested mounting the heavier M2 machine gun , but found the vibration when firing to be detrimental to the aircraft . In all the mounts were imperfect as they blocked easy entry and exit from the main cabin . Defensive armament systems for the CH - 46 Sea Knight have no known designation , but generally comprise pintle mounts at " personnel or cargo doors or windows of the aircraft . " These mounts are usually equipped with either GAU - 15 / A or GAU - 16 / A . 50 caliber , or M60D 7 . 62 mm machine guns . A defensive armament subsystem , the M24 provides a pintle mount for an M60D 7 . 62x51mm machine gun at either left or right front cargo doors on the CH - 47 . The system feeds from standard 200 - round ammunition boxes attached to the weapon . CH - 47 Chinook and ACH - 47A " Guns - a - GoGo " . NOTE : The US Army phased out the M60D in favor of the M240D and subsequently M240H , but it is unknown whether the necessity of a new cradle for the weapon resulted in the system being redesignated . The mount is otherwise the same . EDIT The M240 utilizes a modified M24 mount system that has been redesigned to accommodate the ammunition magazine and a catch bag for containing expended ammunition casings and ammunition links . It also features an improved roller on the pintle to prevent excessive and premature wear to the mount assembly . Mount system designation remains the same , in spite of such an extensive redesign . A defensive armament subsystem , the XM32 provides pintle mounts for either M60D 7 . 62x51mm machine guns or M2HB . 50 caliber machine guns at both cargo door positions and at both rear emergency hatches of the CH - 47 helicopter , with weapons feeding from standard ammunition boxes . This system was developed specifically for the ACH - 47 helicopter . A defensive armament subsystem , the XM33 provides a mount for either an M60D 7 . 62x51mm or an M2HB . 50 - caliber machine gun on the rear cargo ramp of the CH - 47 helicopter . This system was developed specifically for the ACH - 47 helicopter , with the weapon feeding from standard ammunition boxes . An offensive armament subsystem developed for the ACH - 47 helicopter , the XM34 provides two M24A1 20mm cannons with ammunition boxes on sponsons at the front of the aircraft fixed forward . NOTE : These sponsons were also fitted with aircraft - style hardpoints that allowed the mounting of XM159B / XM159C 19 - tube 2 . 75 " - rocket launchers or M18 / M18A1 7 . 62x51mm gun pods . A defensive armament subsystem , the M41 provides a mount for an M60D 7 . 62x51mm machine gun on the rear cargo ramp of the CH - 47 helicopter . The system feeds from standard 200 - round ammunition boxes attached to the weapon . NOTE : The US Army phased out the M60D in favor of the M240D and subsequently M240H , but it is unknown whether the necessity of a new cradle for the weapon resulted in the system being redesignated . The mount is otherwise the same . Defensive armament systems for the H - 53 series as used by the US Navy have no known designation , but generally comprise pintle mounts at " personnel or cargo doors or windows of the aircraft . " These mounts are usually equipped with either GAU - 15 / A , GAU - 16 / A , or GAU - 18 / A . 50 caliber , or M60D 7 . 62 mm machine guns . The . 50 caliber weapons were later supplanted by the GAU - 21 / A . 50 caliber machine gun , which featured a higher rate of fire . The M139 Volcano is a mine dispenser system composed of racks on both sides of the aircraft for up to 40 Canister , Mine , M87 . Each canister contains 6 GATOR Anti - Tank mine and 1 GATOR Anti - Personnel Mine . The M144 is a defensive subsystem that provides mounts and cradles at the two windows between the pilot doors and the main cabin doors on the UH - 60 series of helicopters , each mounting a single M60D 7 . 62x51mm machine gun . UH - 60 Black Hawk / SH - 60 Sea Hawk / HH - 60 Jayhawk / HH - 60 / MH - 60 Pave Hawk . NOTE : The US Army phased out the M60D in favor of the M240D and subsequently M240H , but it is unknown whether the necessity of a new cradle for the weapon resulted in the system being redesignated . The mount is otherwise the same . The External Stores Support System ( ESSS ) provides two stub wings each with two hard points for primarily for external fuel tanks , but can also be used to carry various weapon systems . When equipped with the Extended Range Fuel System ( ERFS ) , the system can support two 230 gallon or 450 gallon external tanks . The system only feeds into the main fuel tank , not the engines directly . The ESSS can also be fitted with a wide range of weapons including up to sixteen AGM - 114 Hellfire missiles , rockets and gun pod s , and other systems . Still in development as of 2003 , the Rapid Airborne Mine Clearance System ( RAMICS ) can be considered an armament subsystem , though its intended targets are strictly naval mines . Comprising a single modified Mk 44 Mod 0 30mm cannon firing the Mk 248 Mod 1 Armor - Piercing Fin - Stabilized Discarding - Sabot Tracer ( APFSDS - T ) round , the RAMICS was intended to be mounted in the cabin of the MH - 60S helicopter , and using its associated sensor package , target and neutralize naval mines at relatively shallow depths . The system is designed to provide a quick and effective mine clearance capability to complement existing methods and others under development for the Navy ' s Airborne Mine Countermeasures ( AMCM ) Program . A version of the TAT - 102 ( Tactical Armament Turret - 102 ) designed specifically for use on the HH - 2C helicopter , the TAT - 102K mounted a single M134 Minigun in a fully traversable turret ( for specifics see the information for the TAT - 102A in the AH - 1 Cobra entry ) . A single such turret would mounted in the nose of the aircraft . The weight of the mount was not suitable for such a small helicopter and the turret was often removed . The XM7 system provided twin M60 machine guns ( unknown type ) on the OH - 6 series of helicopters . It is unclear if both guns were mounted together or whether they were mounted one on each side of the aircraft . As of 1969 the system was listed with the comment " development suspended , " likely in favor of the XM27 . This system was also tested on the YOH - 5A during August 1964 . The XM8 system provides a mount for one M129 40mm grenade launcher for either the OH - 6 or OH - 58 light observation helicopters . The system is provided with an XM70 / E1 sight and 150 rounds of ammunition . The XM8 ' s mount is interchangeable with the M27 system . Armament sub - systems for observation and other light helicopters . OH - 6 Cayuse ( and MD 500 Defender ) . This system could also be mounted on the OH - 58 Kiowa , and was tested on the YOH - 5A during August 1964 . The M27 system provides a mount for one M134 7 . 62x51mm machine gun ( Minigun ) for either the OH - 6 or OH - 58 light observation helicopters . The system is provided with an XM70 / E1 sight and a MAU - 56 / A delinking feeder with 2000 rounds of ammunition . The system has no movement in azimuth , but has 10 degrees of elevation and 24 degrees of depression . The initial XM27 featured a mount similar to a gunpod , which was quickly exchanged for a more aerodynamic fairing , as well as , improvements to the ammunition stowage and other equipment on the XM27E1 . The XM27E1 was standardized as the M27 . The fairing was removed entirely because for ease of maintenance and to reduce weight on the M27E1 . The M27 ' s mount is interchangeable with the XM8 system . As with the XM8 , this system can also be mounted on the OH - 58 Kiowa . Using a mount similar to that used on the XM8 and M27 series , the HGS - 55 was developed by the McDonnell Douglas Helicopter Company ( formerly Hughes Helicopters ) to use the EX 34 Mod 0 7 . 62x51mm chain gun . The weapon is supplied with a 2 , 000 round magazine and the weapon fires between 550 and 700 round per minute . This system was not adopted by the US military for use and no export sales were known to have been made . In service between 1960 and 1972 , the XM1 consisted of two M37C . 30 - 06 machine guns mounted on the landing skids of either the OH - 13 or OH - 23 helicopter . These weapons were fixed forward , but flexible in elevation , with their ammunition ( 500 rounds per gun ) stored externally . The XM1E1 was the product engineering design . OH - 13 Sioux and OH - 23 Raven . NOTE : What would appear to have been a variant of the XM1 system was used by UTTHCO on their HU - 1A ' s ( later UH - 1 A ) for a short period . The M2 system was a variation on the XM1 , replacing the M37C machine guns with 7 . 62x51mm NATO M60C machine guns . The mounts were similar to the XM1 , also providing flexible elevation , with 650 rounds per gun stored externally . The Universal Weapons Pylon is specific to the OH - 58D Kiowa Warrior helicopter , and provides two support racks for various weapon systems . The racks , with stores mounted , may be folded 180 degrees upward for rapid loading into the C - 130 transport aircraft , though the connecting umbilicals must be disconnected to prevent damage . AH - 58D / OH - 58D Kiowa Warrior . There are at least ten authorized armament configurations , which involve a mix of a system specific gun pod mounting the M296 . 50 caliber machine gun ( left side only ) , the M260 7 - shot 2 . 75in / 70mm Lightweight Launcher ( LWL ) , the M279 2 - rail AGM - 114 Hellfire launcher , or a 2 - shot Air - to - Air Stinger ( ATAS ) launcher . The gun pod is fed from a semi - external magazine loaded with 500 rounds of linked ammunition . The US Coast Guard has deployed the MH - 68A to its newly created Helicopter Interdiction Tactical Squadron ( HITRON ) , and it is the only helicopter in USCG inventory specifically tasked with the Airborne Use of Force ( AUF ) mission . These helicopters feature a defensive armament system composed of a single M240G mounted at the port cabin door , along with a Robar Arms RC - 50 rifle attached to the cabin via a bungee cord for disabling hostile light vessels . The kit is also capable of being used on the HH - 65C aircraft . When so fitted the aircraft is designated MH - 65C . Armament sub - systems for dedicated gunships . AH - 1 Cobra . The standard fixed armament for the AH - 1G , AH - 1P ( formerly referred to as AH - 1S Production ) , AH - 1Q , and initial AH - 1S models , this turret unit is similar to the XM64 mentioned later in this section , but was capable of mounting two M134 Miniguns , two M129 40 mm grenade launchers , or one of each weapon . Miniguns fitted are capable of pre - set firing rates of either 2 , 000 or 4 , 000 RPM , while the turret itself has 114 degrees of motion left or right , 17 . 5 degrees of elevation and 50 degrees of depression ( alternate sources describe 110 degrees in azimuth , 20 degrees of elevation and 50 degrees of depression for the M28E1 model specifically ) . Each Minigun is linked to 4 , 000 rounds of ammunition while each grenade launcher is fed from a 300 round magazine . The system is known to have four standard A variants , the M28 / A1 - A3 . However , the actual specifics between variants is vague . From the available information suggests that specific variants were mated to specific iterations of the AH - 1 helicopter . The initial XM28 / M28 were fitted to the AH - 1G , as were the M28E1 / M28A1 . The M28A1E1 / M28A2 was fitted to the AH - 1Q , while the M28A3 ( no developmental variation known ) was fitted to the AH - 1P / S helicopter . There is the possibility that the M28A2 could have been the first unit designed to work with the XM128 / M128 Helmet Sight System ( HSS ) developed primarily for use with TOW armed AH - 1s . An armament subsystem providing a single M195 20 mm cannon on the port inboard pylon of the AH - 1G . 950 rounds of ammunition were stored in boxes faired to the side of the aircraft . The system was primarily pilot controlled , but featured dual controls to be either pilot or gunner controlled . For this purpose the pilot was provided with a M73 sight . The TAT - 102A ( Tactical Armament Turret - 102A ) was the initial main armament for the AH - 1G helicopter , though designed as an interim measure . It is related to the TAT - 101 mentioned in the UH - 1 entry . The turret mounts a single M134 Minigun with 25 degrees of elevation , 90 degrees of depression , and 180 degrees of motion in azimuth , with a slew rate of 80 degrees per second . The TAT - 102A was designated XM64 by the US Army . The Cobra Missile System is a functional development of the XM26 and the TOW missile system developed for the failed AH - 56 helicopter . Originally designed for the AH - 1Q and AH - 1S Cobras , the AH - 1F Modernized Cobra was also rebuilt to use the system . The original iteration of the system comprises launchers allowing for four BGM - 71 TOW missiles per aircraft pylon to be carried , and a TSU or Telescopic Sight Unit , to allow for targeting and guidance of the missile . The TSU has been upgraded with the LAAT ( Laser - Augmented Airborne TOW ) , a day / night range finder , and C - NITE ( Cobra - Night Imaging Thermal Equipment ) , a thermal imagine / FLIR system specifically for the AH - 1S and AH - 1F Cobra helicopters . The standard fixed armament system for the US Army ' s AH - 1S Upgunned Cobra ( eventually redesignated AH - 1E Enhanced Cobra Armament System or ECAS ) and the AH - 1S Modernized Cobra ( eventually redesignated the AH - 1F ) , as well as , the US Marine Corps ' AH - 1J , AH - 1T , AH - 1W , and AH - 1Z helicopters . The system was designed to fit either the M197 20 mm three barreled cannon or the XM188 30 mm three barreled cannon . In practice the M197 was the standard fit and the XM188 was not adopted for service . The turret has 110 degrees of motion in azimuth , 21 degrees of elevation , and 50 degrees of depression , with a slew rate in azimuth of 80 degrees per second and in elevation and depression of 60 degrees per second . As with the M28 series , the specifics between variants of the M97 are vague . Five Standard A models are known to exist , M97 / A1 - A4 . Sources suggest that individual variants of the turret were specific to certain variants of the AH - 1 as with the M28 series . The M97A1 ( and possibly the M97 ) was fitted to the AH - 1S Upgunned Cobra , the M97A2 / A3 to the AH - 1S Modernized Cobra ( AH - 1F ) , and the M97A4 to production AH - 1Fs . Other sources say that the M97A3 was refitted to AH - 1E ECAS and the M97A2 was the initial armament for the AH - 1S Modernized Cobra , agreeing that the M97A1 was the original fit to the AH - 1S Upgunned Cobra . There is also the possibility that the differences have something to do with the associated equipment for the M197 cannon , including the use of the M89 or M89E1 delinking feeder . The M97 was also fitted to the AH - 1J , but it is unclear if the AH - 1T , AH - 1W , and AH - 1Z used variants of the M97 series . The subsystem used on the AH - 1T and AH - 1W has a designation in the USAF ' s Aeronautical and Support Equipment Type Designation System ( ASETDS ) , A / A49E - 7 . The turret in the system is also designated under the ASETDS system , as the GTU - 1 / A . How this system differs from its US Army counterparts is unknown . An amendment to the official Military Specification , MIL - F - 85668 ( AS ) , put out by the United States Naval Air Systems Command on 15 November 1995 , actually listed the " A / A49E - 7 ( V4 ) " as inactive pending a new design , and listed the system as relevant only to the " AH - 1T ( TOW ) . " A competing universal turret design to the M97 put forward by Emerson Electric , the XM120 could be fitted with a number of weapons including the M60C 7 . 62x51 mm machine gun , M134 Minigun , M197 20 mm three barreled cannon , XM188 30 mm three barreled cannon , and was in fact tested with the XM140 30 mm cannon . A nose turret with one M129 40 mm grenade launcher with 300 rounds . In light of the failure of the AH - 56 was proposed as a replacement for the M5 system on the UH - 1 helicopter . Designed to be interchangeable with the XM53 . Belly turret with a single XM140 30 mm cannon . Use on other helicopters was also debated . A nose turret with one XM196 7 . 62x51 mm machine gun . Also said to be suitable for the UH - 1 series of helicopters . Designed to be interchangeable with the XM51 . The only type classified subsystem for the AH - 64 series , the M139 is composed of the Aerial Rocket Control System ( giving the aircraft the ability to fire members of the Hydra 70 / Mk 66 2 . 75 in / 70 mm rocket family ) , a dispenser interface ( controlling the M130 chaff / flare dispenser , also used on the AH - 1 helicopter ) , and the Area Weapon Subsystem . AH - 64 Apache . The Area Weapon Subsystem is made up of a single M230 30 mm cannon , turret and assembly , ammunition feed , and other electronic components for the functioning of the system . The unit is capable of 100 degrees of motion in azimuth left or right , 11 degrees of elevation and 60 degrees of depression , and feeds from an ammunition magazine with 1 , 200 rounds . The RAH - 66 Comanche was intended to have a gun system designed jointly by Boeing and Sikorsky . The system was to use the XM301 lightweight gun , and fed linked ammunition from a 500 round storage drum . The turret itself had 120 degrees of movement in azimuth , with 15 degrees of elevation and 45 degrees of depression . The TGS was supposed to be ready for deployment with the Comanche helicopter during the FY04 period , but the cancellation of the Comanche ended further development of this system . References . Sources . " Government Documentation " " Secondary Sources "