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Lockheed Martin Trident (missile)

Lockheed Martin · Ballistic · UK · Cold War (1970–1991)

The Trident is an American submarine-launched ballistic missile (SLBM) — Lockheed Martin's principal US Navy + Royal Navy sea-based nuclear-delivery system + the second-most-numerous nuclear-warhead delivery vehicle in the US nuclear arsenal. Lockheed Martin (originally Lockheed Missiles & Space Company) has produced two Trident generations: Trident I (C4, 1979) + Trident II (D5, 1990-present). The Trident II D5 is the current variant; ~190 missiles are deployed across 14 US Navy Ohio-class + 4 Royal Navy Vanguard-class ballistic-missile submarines.

The Trident II D5 (current variant) is a 3-stage solid-fuel SLBM. Range 12,000 km (single warhead) or 7,500 km (MIRV with 8 warheads). Length 13.5 m, weight 59,000 kg, payload 2,800 kg. Warheads: up to 8 × W76-1 (100 kt) or W88 (475 kt) MIRVs per missile, with optional W76-2 low-yield (5 kt) variant for limited-strike options. Reentry vehicle: Mk 4 (W76) or Mk 5 (W88) carbon-carbon composite heat shield. CEP (Circular Error Probable): ~90 m at maximum range — accurate enough for hardened-silo counterforce missions. The SLBM is launched submerged from 30 m depth via gas-generator cold-launch (the missile exits the tube, the rocket ignites at surface).

Trident service spans nearly 5 decades. The Trident II D5 first deployed on USS Tennessee in 1990 + is scheduled to continue in service through 2042 on the Ohio class + 2080+ on the planned Columbia class + Dreadnought-class submarines. Royal Navy Vanguard-class submarines + planned Dreadnought-class will continue Trident use through ~2070. About 49 successful + 7 failed test launches have been completed since 1990; the most-recent test (January 2024) was a failure (UK Royal Navy HMS Vanguard test, missile fell into the ocean after first-stage ignition). Trident II D5 production has continued at Lockheed Martin Sunnyvale + (now) Camden Arkansas for 35 years — making it the longest-continuous-production long-range missile in US inventory.

For Kids — a shorter, friendlier version

The Trident is a long-range rocket made by Lockheed Martin. It is launched from submarines deep underwater. The American Navy and the British Navy both use it. It is one of the most important rockets in the American defense system.

There have been two versions of the Trident. The first was called Trident I, made in 1979. The second is called Trident II D5, made in 1990. The Trident II D5 is still used today. It is the newer and more powerful version.

The Trident II D5 is about 13 and a half meters long. That is longer than two large cars parked end to end. It weighs around 59,000 kilograms. It can travel up to 12,000 kilometers on a single flight. That is farther than flying from New York to Australia.

The rocket is carried inside special submarines. American submarines called Ohio-class carry these rockets. British submarines called Vanguard-class carry them too. There are about 190 of these missiles deployed across 18 submarines in total.

The rocket launches while the submarine is underwater, about 30 meters below the surface. A gas system pushes it out of the submarine first. Then the rocket engine fires once it is clear of the water.

Fun Facts

The Trident II D5 is longer than two large cars parked end to end.
It can fly up to 12,000 kilometers — far enough to cross entire oceans.
The rocket is launched from underwater, about 30 meters below the surface.
Lockheed Martin has been making Trident II D5 rockets since 1990.
About 190 Trident missiles are spread across 18 submarines right now.
The rocket has three separate stages that fire one after another.
It uses solid fuel, which means it is always ready to launch quickly.
The Trident II D5 can carry its payload to a target with amazing accuracy, landing within about 90 meters of its aim point.

Kids’ Questions

Who makes the Trident rocket?

The Trident is made by a company called Lockheed Martin. They have been building Trident rockets since 1979. The company was originally called Lockheed Missiles and Space Company.

Which countries use the Trident?

Both the American Navy and the British Navy use the Trident II D5. American submarines called Ohio-class carry them. British submarines called Vanguard-class carry them too.

How does the Trident launch from a submarine?

A special gas system pushes the rocket out of the submarine while it is underwater. Once the rocket is clear of the water, its engine fires. This is called a cold-launch system.

How far can the Trident travel?

The Trident II D5 can travel up to 12,000 kilometers when carrying a single payload. That is far enough to reach almost any place on Earth from the ocean. It is one of the longest-range rockets ever made.

Variants

Trident I C4 (1979-2005): Original variant. Retired.
Trident II D5 (1990-present): Current variant. US Navy + Royal Navy.

Notable Operators

US Navy (1990-present): 14 Ohio-class + planned Columbia-class submarines.
Royal Navy (1994-present): 4 Vanguard-class + planned Dreadnought-class submarines.

Frequently Asked Questions

What is the W76-2 low-yield warhead?

The W76-2 is a Trident II variant entered service in 2019 with a 5-kiloton yield (vs the standard W76-1's 100 kt). The Trump administration commissioned the W76-2 to provide the US with a low-yield SLBM option that would avoid the 'use-them-or-lose-them' dilemma of large-yield first-use scenarios — i.e. an option to respond to a Russian limited-nuclear-use scenario without escalating to full-scale exchange. Critics argue the W76-2 lowers the nuclear-use threshold + increases first-use risk. The W76-2 is reportedly deployed on a small number of Trident II rounds aboard US Navy submarines; deployment numbers + locations are classified.

Sources

Wikipedia — Trident (missile)