UGM-96 Trident I

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. The Trident was intended to have longer range than the Poseidon, allowing the fleet to maintain a longer distance from the target, enhancing survivability. It was retired in 2005, having been replaced by the Trident II.^[2][3]

UGM-96 Trident I (C4)
The first launch of a Trident I with a drag-reducing aerospike, from Cape Canaveral, on 18 January 1977
Type	SLBM
Place of origin	United States
Service history
In service	1979 to 2005
Used by	United States Navy
Production history
Manufacturer	Lockheed Missiles Division
Specifications
Mass	74,630 pounds (33,850 kg)
Length	34.1 feet (10.39 m)
Diameter	74 inches (1.88 m)
Warhead	Up to eight W76 warheads in Mark 4 RBs with a yield of 100 kilotonnes of TNT (420 TJ) each.
Engine	Solid-fuel rocket
Operational range	4,600 miles (7,400 km)
Guidance system	Astro-inertial guidance
Accuracy	CEP: 229-500 m[1]
Launch platform	Ballistic Missile Submarine

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

Twelve James Madison- and Benjamin Franklin-class submarines were retrofitted with Trident I missiles, which replaced older Poseidon missiles. The first eight Ohio-class submarines were armed with Trident I missiles. The Ohio-class submarines were designed for the Trident II missiles, but used Trident I missiles until the Trident II missiles became available.^[3]

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

• Trident (missile)
• UGM-133 Trident II