The unguided Zuni 5.0-Inch [130 mm] Rocket was originally developed for both air-to-air and air-to-ground applications, but is currently used almost exclusively in the later role. The rockets can also be used to illuminate and mark ground targets, and deliver chaff countermeasure systems. The rockets are assembled into complete all-up-rounds to deliver a variety of payloads. The type of fuze and warhead combination is determined by the tactical requirement.
The Zuni unguided rocket uses folding fins for aerodynamic stability. The 26.7 kilogram Mk-16 Mod 3 motor incorporates a double-base solid propellant with a burn time of 1.2 to 1.5 seconds, depending on ambient temperature. The motor is is 1.95 m long with a diameter of 130 mm. In the early 1970s a PIP was conducted to develop and qualify a 5.0 inch rocket motor with improved accuracy and performance. DT of the Mk-71 Mod 1 was completed and a release for production was granted in February 1973. Operational Test (OT) was conducted in 1972-73. Full production of the Mk-71 Mod 1 motor began in September 1973. The rocket motor Mk 71 Mod 1 consists of a motor tube and contact band assembly, the igniter, the stabilizing rod assembly, the charge support spring, spacer and cup assembly, the propellant grain assembly, the seal ring, the nozzle and fin assembly, the radiation hazard barrier and shielding band. The Mk 71 Mod 1 motor is classified as HERO safe ordnance when the radiation hazard barrier and shielding band are in place.
The warhead is delivered without the fuze installed. The fuze and warhead combination is determined by mission need. Overall rocket length and weight will vary dependent on fuzed warhead combination. Standard warheads include the Mk 24 GP explosive warhead that is 0.48 m long, has a diameter of 133 mm and weighs 22 kg, and the Mk 32 shaped charge warhead for anti-armour targets that is 0.76 m long, has a diameter of 133 mm and weighs 20 kg. On 14 January 1969 a fire aboard Enterprise resulting from detonation of a MK-32 Zuni rocket warhead overheated by exhaust from an aircraft starting unit, took 27 lives, injured 344 and destroyed 15 aircraft.
The rockets are fired from the all weather LAU-10 launcher, which can be used at speeds up to Mach 1.2. The 5.0 Inch Rocket launchers are a cylindrical construction of four aluminum launch tubes. These launch tubes are held together with metal ribs and are covered by an aluminum skin. Launchers can be fitted with forward and aft frangible fairings depending on overall rocket length and fuzing for airborne configuration. The launcher has a frangible nose and tail fairings which disintegrate on firing, and the rockets can be fired singly or in ripple mode. The 5.0 Inch Rocket System uses the four round LAU-10C/A (shore-based use only) and LAU-10D/A (shore-based or shipboard use) rocket launchers. The difference between the LAU-10C/A and LAU-10D/A reusable rocket launchers is the external thermal coating on the LAU-10D/A that greatly prolongs cook-off protection time. Full production of these launchers began in September 1973.
Aircraft rockets were China Lake's raison d'etre at its establishment. The early forward-firing aircraft rockets developed by the CalTech-NOTS team included the 5.0-Inch Aircraft Rockets and the 5.0-Inch High-Velocity Aircraft Rocket [HVAR] "Holy Moses" which remained in the Fleet until the mid-1960s. Folding-fin aircraft rockets (FFARs) are another highly successful China Lake product, with literally millions of the 5.0-inch Zuni having been fired in combat. This rocket has been built under licence in Belgium by Forges de Zeebrugge (now a subsidiary of Thomson Brandt) since 1966. There have been no recent improvements to the 5.0 Inch Rocket.
HE Fragmentation Mk 63 Mod 0
HE General Purpose Mk 24 Mod 0,1
Anti Tank/Anti Personnel Mk 32 Mod 0
Flare (Illumination) Mk 33 Mod 1
Smoke WP Mk 34 Mod 0
Smoke RP Mk 34 Mod 2
Chaff/Countermeasure Mk 84 Mod 4, RR-182/AL
Practice Mk 6 Mod 7, Mk 24 Mod 0, Mk 32 Mod 0