Hydra-70 2.75-inch (70mm) Family of Rockets

General Dynamics Ordnance and Tactical Systems is the system integrator of the 2.75-inch (70mm) Hydra-70 family of rockets. The Hydra 70 rocket is a 2.75-inch fin-stabilized unguided rocket used primarily in the air-to-ground role. It can be equipped with a variety of warheads, and in more recent versions, guidance systems for point attacks. The Hydra is widely used by US and allied forces, competing with the Canadian CRV-7, with which it is physically interchangeable. General Dynamics has produced more than four million Hydra-70 rockets since 1996 in support of the Army’s Joint Attack Munition Systems Project Office

These rockets include unitary and cargo warheads for use against point and area targets, providing the user a lethal and lightweight weapon system with multi-mission capability. The rocket system contains three components: the MK66 MOD 4 rocket motor, one of the nine warheads, and the associated point-detonating, omni-directional, remote-set fuze(s). When these components are combined, they provide a tailor-made solution to the warfighter’s situational requirements. Warheads are available in either unitary or cargo configurations. Fitted to the MK66 MOD 4 motor, these warheads provide low-cost munitions capable of area suppression and defeating threats at extended ranges, as well as providing battlefield obscuration, illumination and marking.

The main change made to produce the Hydra was the Mk. 66 motor which uses a new propellant that offers considerably more thrust, 1,335 pounds-force (5,940 N) (Mod 2/3) 1,415 pounds-force (6,290 N) (Mod 4). The fins of the Mk 40 flipped forward from the rear when the rocket left the launching tube, but in the Hydra they are curved to match the outside diameter of the rocket fuselage and flip sideways to open, which is referred to as WAFAR (Wrap-Around Fin Aerial Rocket) instead of FFAR (folding-fin aerial rocket). To improve stability during the time while the fins are still opening, the four motor nozzles have a slight cant angle to impart a spin while the rocket is still in the launch tube.

Hydra-70 provides the Army with affordable firepower matched to the mission for effective engagements and area suppression of a long list of lower-value targets on the battlefield. The Government/Industry team is planning subsequent block enhancements to overall performance (i.e., lethality, safety, range, precision and IM) of the entire family of rockets as funding and other technologies for warhead, fuze, propulsion and launcher improvements are made available. Hydra-70 fires from the existing seven and 19-tube launchers and can be mounted on most rotary and fixed-wing aircraft, including: the OH-58D(R) Kiowa Warrior and AH-64D Apache Longbow, as well as the Marine Corps’ AH-1 Cobra and F-16.