Military

Longhorn Army Ammunition Plant

Longhorn AAP is 3.5 miles west of the Louisiana/Texas border in Karnack, 12 miles from Marshall, TX. It includes 451 buildings on 8,493 acres of land. This World War II era facility both produced and destroyed missiles.

Longhorn AAP was established to support mobilization requirements for World War II. From 1945 to 1952, it was on standby and GOGO status. The plant was reactivated in 1952 and operated by Universal Match Corporation. Reactivated during the Korean War, Longhorn took on an expanded mission that included loading, assembling, and packing rocket motors and pyrotechnic ammunition. The Thiokol Corporation, which operated a facility at Redstone Arsenal, received the contract to rehabilitate a World War II era liquid fuel facility into a solid fuel rocket motor plant. In 1955, Plant 3, which was operated by Thiokol Corporation (later Morton Thiokol, Inc.), was designated to produce solid propellant rocket motors. Production on the original Nike-Hercules program for sustainer motors began at this plant in 1956. Thiokol also produced propellants and motors for the Falcon, Lacrosse, Honest John, and Sergeant missiles. As production increased, so did capacity. In 1959 a Main Rocket Motor Assembly Building (45E) was constructed along with a Static Test Building (25T).

During the Vietnam War, Longhorn AAP produced illuminating and pyrotechnic ammunition. In 1977, the plant was designated a CORE* facility for the production of solid propellant rocket motors and pyrotechnic-type ammunition.

This facility produced both the first and second stages of the Pershing IA missile. The facilities were modernized in the late 1970s and early 1980s. With the signing of the INF Treaty on December 8, 1987, Longhorn took on a new mission. Along with Pueblo Depot, Colorado, this facility was used to destroy Pershing IA and II missiles to comply with the treaty. After a static burn, the missiles were crushed.

Its current workload includes loading, assembly, and pack-out of illuminating munitions, infrared flares, signals and simulators, but it is currently listed on inactive status. Thiokol Corporation remains the contractor.