UGM-96 Trident I (C4)
The first launch of a Trident I with a drag-reducing aerospike, from Cape Canaveral, on 18 January 1977
Place of originUnited States
Service history
In service1979 to 2005
Used byUnited States Navy
Production history
ManufacturerLockheed Missiles Division
Mass73,066 pounds (33,142 kg)
Length33 feet (10.2 m)
Diameter71 inches (1.8 m)
WarheadUp to eight W76 warheads in Mark 4 RBs with a yield of 100 kilotonnes of TNT (420 TJ) each.

EngineSolid-fuel rocket
4,600 miles (7,400 km)
Astro-inertial guidance
AccuracyCEP: 229-500 m[1]
Ballistic Missile Submarine

The UGM-96 Trident I, or Trident C4, was an American submarine-launched ballistic missile (SLBM), built by Lockheed Martin Space Systems in Sunnyvale, California. First deployed in 1979, the Trident I replaced the Poseidon missile. It was retired in 2005, having been replaced by the Trident II.[2]

The missile was a three-stage, solid-fuelled system, capable of carrying up to eight W76 warheads in the Mark 4 RB.

The first eight Ohio-class submarines were armed with Trident I missiles. Twelve James Madison- and Benjamin Franklin-class submarines were also retrofitted with Trident I missiles, which replaced older Poseidon missiles.

In 1980, the Royal Navy requested Trident I missiles under the Polaris Sales Agreement. In 1982, the agreement was changed to supply Trident II instead.

See also


  1. ^ Matthew G. McKinzie; Thomas B. Cochran; Robert S. Norris; William M. Arkin. THE U.S. NUCLEAR WAR PLAN: A TIME FOR CHANGE (PDF) (Report). Natural Resources Defense Council. p. 19. Archived (PDF) from the original on 2021-07-31. Retrieved 2021-09-01.
  2. ^ Popejoy, Mary (November 5, 2005). "USS Alabama Offloads Last of C4 Trident Missiles". US Navy. Archived from the original on September 12, 2007. Retrieved May 16, 2012.