M55 rocket

M55 rocket was a United States Army chemical weapon designed during the Cold War. It was a solid-propellant rocket armed with a unitary warhead filled with a nerve agent. The system was deployed briefly in the early 1960s before being removed from service due to significant safety concerns.

Development and design

The development of this chemical munition was driven by the United States' chemical weapons program during the heightened tensions of the Cold War. Primary design work was conducted at Redstone Arsenal in Alabama. The rocket itself was a simple, spin-stabilized, unguided missile intended for area saturation. Its key design feature was the warhead, which contained a single bulk fill of liquid nerve agent, either Sarin (designated GB) or the more persistent VX. The complete weapon system included the rocket and its M91 rocket launcher, a ground-based multiple rocket launcher mounted on a modified M2 half-track or later the M113 armored personnel carrier. The entire system was designed for rapid deployment and massed fire to contaminate large areas behind enemy lines, targeting troop concentrations and logistics hubs.

Operational history

The system entered the inventory of the United States Army around 1959. Units such as those stationed in West Germany as part of NATO forward defenses were equipped with these weapons. However, its operational service was extremely brief. By 1964, all units had been withdrawn from active deployment. The primary reason for this swift retirement was the discovery of severe and inherent safety defects. Investigations, including those by the Rocky Mountain Arsenal, revealed that the chemical agent within the warheads could leak due to corrosion and faulty seals. Furthermore, the propellant grains were found to be unstable, posing a high risk of cook-off or accidental detonation during storage or transport. This made the weapon as dangerous to the handling troops as to its intended targets, leading to a complete recall and phase-out from the active arsenal.

Variants

There were no major production variants of the rocket itself. The designation primarily differed based on the type of nerve agent fill. The standard models were the M55 GB, filled with Sarin, and the M55 VX, filled with VX. The launch system, the M91 rocket launcher, could be mounted on different platforms. The initial configuration used the M2 half-track, but studies were conducted for integration onto the newer M113 armored personnel carrier to improve mobility and crew protection. These were not distinct rocket variants but different implementations of the overall weapon system.

Specifications

* **Type:** Unguided, solid-propellant rocket * **Warhead:** Unitary chemical, filled with approximately 10 pounds (4.5 kg) of Sarin (GB) or VX nerve agent * **Launch System:** M91 rocket launcher (45-round capacity) * **Launch Platform:** Mounted on M2 half-track or M113 armored personnel carrier * **Propulsion:** Solid-fuel rocket motor * **Guidance:** None (ballistic trajectory) * **Crew:** Varied by launch vehicle platform

Operators

The sole operator was the United States Army. The weapons were held by specialized chemical corps units within the army, primarily intended for use in the European theater under the auspices of NATO. No rockets were exported to other countries under the United States' arms control policies of the era, and all stockpiles were eventually slated for destruction under later treaties like the Chemical Weapons Convention.

Category:Chemical weapons of the United States Category:Rockets and missiles of the United States Category:Cold War weapons of the United States