A nuclear weapon convoy is a cluster of vehicles travelling by road in convoy formation. It can be:
- Carrying Trident nuclear warheads
- Travelling empty to collect or having unloaded nuclear warheads
- Engaged in an exercise simulating the transport of warheads
- En route to or from an accident & emergency exercise on a military base.
The Trident warheads are carried in large crates inside the green trucks. They are fully assembled and complete. The core of the warhead is a ball of plutonium and uranium. This is surrounded by specially developed conventional high explosives which would be ignited to create the critical mass necessary for a nuclear detonation when launched and targeted.
As well as nuclear warheads these convoys can carry Special Nuclear Materials (SNM).