OH-58D Kiowa Warrior

M260 70mm ROCKET LAUNCHER

Umbilical Weapon Harnesses (Weapons Electrical Cables)

M260 70mm (2.75 Inch) ROCKET LAUNCHER

The M260 Rocket Launcher is mounted to the ejector rack on either side of the OH-58D helicopter. The launcher consists of a Firing Connector which provides electrical power from aircraft to launcher, a Fuzing Connector which provides fuzing capabilities for accurate delivery of ordnance, Suspension Lugs which mount the Gun Pod to the pylon, Rocket Tubes to hold rockets in the launcher for transport and firing, Igniter Arms which provide electrical contact points for ignition of rockets, Skin which holds the tubes together in the launcher, and Umbilical Connectors that connect the remote fuzing Hydra 70 Rockets to the launcher. Additional information regarding the M260 Rocket Launcher can be found in TM 9-1055-460-13&P.
M260 seven-tube rocket launcher

SUSPENSION LUGS: Attach launcher to aircraft for transport.

FIRING CONNECTOR: Connects electrical power from aircraft to launcher.

FUZING CONNECTOR: Allows fuzing capabilities for more accurate delivery of ordnance.

SKIN: Holds rocket tubs together in launcher.

ROCKET TUBES: Hold rockets in launcher for transport and firing.
Rocket tubes

UMBILICAL CONNECTORS: Allows remote fuzing rockets to connect to launcher.
Umbilical connectors

IGNITER ARMS: Electrical contact points for ignition of rockets.
Igniter arms

HYDRA 70 ROCKET SYSTEM *

* U.S. Army Industrial Operations Command (IOC) system. Theoretically part of the armament subsystem through integration components.

The 2.75 inch Folding-Fin Aerial Rocket (FFAR), originally developed by the U.S. Navy for use as a free-flight aerial rocket in the late 1940s, was used during both the Korean and Vietnam wars. The 2.75 inch rocket system has a rich history of providing close air support to ground forces from about 20 different firing platforms, both fixed-wing and armed helicopters, by all U.S. armed services. To provide some stability the four rocket nozzles were scarfed at an angle to impart a slight spin to the rocket during flight.
OH-58D Kiowa Warrior firing 2.75 inch rocket
Kiowa Warrior firing 2.75 inch rocket

The family of Hydra 70 (70mm) 2.75 inch rockets perform a variety of functions. The war reserve unitary and cargo warheads are used for anti-materiel, anti-personnel, and suppression missions. The Hydra 70 family of Folding-Fin Aerial Rockets (FFAR) also includes smoke screening, illumination, and training warheads. In the U.S. Army, Hydra 70 rockets are fired from the AH-64A Apache/AH-64D Apache Longbow using M261 19-tube rocket launchers, and the OH-58D Kiowa Warrior and the AH-1F "modernized" Cobra using seven-tube M260 rocket launchers. The M260 and M261 are used with the MK66 rocket motor, which replaced the MK40. The MK66 has a reduced system weight and provides a remote fuze setting interface.
M261 19-tube and M260 seven-tube rocket launchers

Note: The M260 seven-tube launcher, NSN 1055-01-070-9113, LIN L45199, and the M261 19-tube launcher, NSN 1055-01-071-0064, LIN L45131, are Class VII major items, and are free issue to all U.S. Army units that are authorized these items.


Kiowa Warrior seven-Tube and Apache 19-Tube Rocket Launchers
Hydra 70 Rocket System

The AH-1G Cobra and the UH-1B "Huey" used M158 seven-tube and M200 19-tube rocket launchers. The M158 and M200 were used with the MK40 rocket motor. The MK40 rocket motor was replaced by the newer MK66 rocket motor. The M158 and M200 rocket launchers are not compatible with the MK66 rocket motor. The Hydra 70 rocket system is also used by the U.S. Marine Corps, the U.S. Navy, and the U.S. Air Force.
M158 seven-tube rocket launcher on M21 armament subsystem
M200 19-tube rocket launcher on M156 armament subsystem

Hydra 70 warheads fall into three categories:
(1) Unitary warheads with impact-detonating fuzes or remote-set multi-option fuzes.
(2) Cargo warheads with airburst-range, with setable fuzes using the "wall-in-space" concept or fixed standoff fuzes.
(3) Training warheads.

*ROCKET WARHEADS (IMPACT, AIRBURST AND TRAINING)

M151 High Explosive. The M151 HE is an antipersonnel, antimateriel warhead and is traditionally referred to as the "10 Pounder." The bursting radius is 10 meters; however, high velocity fragments can produce a lethality radius in excess of 50 meters. The nose section is constructed of malleable cast iron that is threaded to receive the fuze. The base section is constructed of steel or cast iron and is threaded so that it can be attached to the rocket motor. The base section and the nose section are welded (brazed) together. Total weight of the loaded, unfuzed, warhead is 8.7 pounds, of which 2.3 pounds is composition B4. The M151 can be used M423, M429, and M433 fuzes.

M274 Smoke Signature (Training). This training rocket provides a ballistic match for the M151 HE warhead. The casing is a modified WTU-1/B with vent holes or blowout plugs. A modified M423 fuze mechanism is integral to the warhead. A cylindrical cartridge assembly is in the forward section of the casing; it contains approximately 2 ounces of potassium perchlorate and aluminum powder that provides a "flash, bang, and smoke" signature. The M274 weighs 9.3 pounds.

M261 High-Explosive Multipurpose Submunition.

The MPSM warhead provides improved lethality against light armor, wheeled vehicles, materiel, and personnel. It has a plastic nose cone assembly, an aluminum warhead case, an integral fuze, an expulsion charge, and nine M73 submunitions. The primary warhead fuze, M439, is remotely set with the ARCS, MFD, or RMS to provide range settings (time of flight) from 500 meters to approximately 7,000 meters. On the AH-1, the RMS is programmable only from 700 meters to 6,900 meters.

Initial forward motion of the rocket fuze timing. The expulsion charge is initiated at a point before and above the target, approximately 150 meters, depending on the launch angle. The submunitions are separated by ejection, and arming occurs when the ram air declarator deploys. The RAD virtually stops forward velocity and stabilizes the descent of the submunition. An M230 omnidirectional fuze with an M55 detonator is used on each submunition and is designed to function regardless of the impact angle.

Each submunition has a steel body that has a 3.2-ounce shaped charge of composition B for armor penetration. The submunition is internally scored to optimize fragments against personnel and materiel. Upon detonation, the shaped charge penetrates in line with its axis and the submunition body explodes into high velocity fragments (approximately 195 at 10 grains each up to 5,000 feet per second) to defeat soft targets. The fuzed weight of the M261 is 13.6 pounds.

Approximate target area coverage. At shorter ranges, the RAD takes longer to overcome momentum, increasing dispersion. As range increases, the rocket loses momentum, increasing the effectiveness of the RAD. This increased effectiveness reduces submunition drift and ground dispersion. Forestation, other vegetation, and natural or man-made structures within the target area may cause the submunition to detonate or land in a dispersion pattern other than the one shown in Figure 5-6.

Probability of impact angle. Aerodynamic forces affecting submunitions during vertical descent may prevent them from landing upright (0 degrees off center). Sixty-six percent of the time a submunition will land 5 degrees off center; 33 percent of the time a submunition will land 30 degrees off center.

MPSM lethality potential. Each M73 HE submunition has a shaped charge that can penetrate in excess of 4 inches of armor. A submunition that lands 5 degrees off center has a 90-percent probability of producing casualties against prone, exposed personnel, within a 20-meter radius. A submunition landing 30 degrees off center has a 90-percent probability of producing casualties within a 5 meter radius.


M267 MPSM Smoke Signature (Training). The M267 MPSM training warhead operationally, physically, and ballistically matches the M261. Three M75 practice submunitions and six inert submunition load simulators take the place of the nine HE submunitions in the M261 warhead. Each practice submunition contains approximately 1 ounce of pyrotechnic powder. An M231 fuze with an M55 detonator is used with practice submunitions.

M257 Illumination. The M257 illumination warhead provides one million candlepower for 100 seconds or more. It can illuminate an area in excess of 1 square kilometer at optimum height. A deployed main parachute descent is approximately 15 feet per second. An M442 integral fuze provides a standoff range of approximately 3,000 meters with the MK 40 motor and approximately 3,500 meters with the MK 66 motor. The weight of the M257 is 10.8 pounds, of which 5.4 pounds is magnesium sodium nitrate.

M229 High-Explosive. The M229 HE warhead is currently in the inventory. An elongated version of the M151, it is commonly referred to as the "17 Pounder." The M229 filler consists of 4.8 pounds of composition B4 and has the same fuzes as the M151. Its unfuzed weight is 16.4 pounds.

M156 White Phosphorous (Smoke). The M156 is primarily used for target marking and incendiary purposes. It ballistically matches the M151 and is of similar construction. Filler for the M156 is 2.2 pounds of WP with a .12-pound bursting charge of composition B. The approximate weight of the fuzed warhead is 9.7 pounds. The M156 uses M423 and M429 fuzes.

M247 High-Explosive. The M247 is no longer in production; however, some of these warheads may still be found in war reserve stockage. With a shape charge for an antiarmor capability, the M247 employs a cone shaped charge like that of the M72 LAW. The point initiated detonating fuze (M438) is an integral part of the warhead. The weight of the M247 is 8.8 pounds, of which 2.0 pounds is composition B.

M255E1 Flechette. The M255E1 flechette warhead, which contains approximately 1,180 60-grain hardened steel flechettes, is in limited production. It is designed for use with the M439 fuze and has possible air-to-air as well as air-to-ground application.