Defence Nuclear Material Transport Operations

Defence Nuclear Material Transport Operations refer to the movements of military Defence Nuclear Materials (DNM) within, to and from the United Kingdom. Defence Nuclear Material Transport Operations are also known as DNM Transportation; Defence Nuclear Material in transit; Nuclear movements; and DNM movements.

The Special Escort Group of the Ministry of Defence Police, SEG (MDP), escort the nuclear materials and remain on standby during their transit. Immediate Response Forces (IRF) are embedded within the road and rail transports, and on standby with air transports.

Defence Nuclear Materials are moved using the following transport means:

Trident NW's are contained within PD AWG 516 packages. These are kept on Load Transfer Platform Trolleys (LTPT) until moved by crane or put onto Truck Cargo Heavy Duty (TCHD) carriers. Hence these transport operations are often referred to as TCHD Convoys.

The Mark I TCHD's were AEC Mammoth Majors. The Mark II TCHD carriers were 7-axle articulated lorries, the four-axle tractors for which were built by Foden. These vehicles have cargo bodies designed to provide extra protection to the nuclear weapon containers. The Mark III vehicle introduced in 2011, which replaced the Foden towing a similar three-axle trailer, is a similarly capable four-axle tractor based on a highly modified Mercedes-Benz Actros, which has its three-pointed star Mercedes-Benz logo removed.

The primary logistical movement of nuclear weapons is from the Atomic Weapons Establishment (AWE) in Berkshire, England, to the Royal Naval Armaments Depot RNAD Coulport in Argyll, Scotland (part of HMNB Clyde). Because the warheads need to be constantly refurbished, batches are shuttled by road convoy several times a year. Convoys use Staging Posts (SP) and Crew Change Locations (CCL) during this journey.

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