UGM-133 Trident II

UGM-133 Trident II, or Trident D5 is a submarine-launched ballistic missile, built by Lockheed Martin Space Systems in Sunnyvale, California, and deployed with the US and Royal Navies. It was first deployed in 1990, and is still in service.

Trident II was designed to be more sophisticated than Trident I (retired in 2002), and have a greater range and payload capacity. It is accurate enough to be used as a first strike weapon. All three stages of the Trident II are made of graphite epoxy, making the missile much lighter than its predecessor. Trident II missiles are carried by US and British Vanguard-class submarines. USS Tennessee (SSBN-734) was the first submarine to be armed with Trident IIs. Trident II missiles are currently carried by fourteen Ohio class and four Vanguard class SSBNs, with 24 missiles on each Ohio class and 16 missiles on each Vanguard class. The four oldest Ohio class submarines were withdrawn from the strategic role and converted to SSGNs beginning in 2002, capable of firing up to 168 Tomahawk missiles each and supporting SEAL operations. There have been 148 successful test flights of the D5 missile since 1989, with the most recent being from a Ohio-class submarine in September 2013.

The development contract for Trident II was issued in October 1983. The first Trident II launch occurred in January 1987, and the first submarine launch was attempted by Tennessee, the first D-5 ship of the Ohio class, in March 1989. The launch attempt failed because the plume of water following the missile rose to greater height than expected, resulting in water being in the nozzle when the motor ignited. Once the problem was understood relatively simple changes were very quickly made but the problem delayed the Initial Operational Capability (IOC) of Trident II until March 1990.

It is estimated that 540 missiles will be built by 2013. The Trident D5LE (life-extension) version will remain in service until 2042.

Specifications

 * Purpose: Strategic Nuclear Deterrence
 * Unit Cost: US$ 30.9 million
 * Range: Varies, based on payload, but rumored to be up to 11300 km
 * Maximum speed: > 6000 m/s.
 * Guidance system: inertial, with Star-Sighting; GPS experiments done but not deployed.
 * CEP: Requirement: 90 –. That demonstrated by flight tests is classified, but rumored to be significantly better.
 * Warhead (in USA usage only): nuclear MIRV up to eight W88 (475 kt) warheads (Mark 5) or eight W76 (100 kt) warheads (Mark 4). The Trident II can carry up to 12 MIRV warheads but START I reduces this to eight and SORT reduces this yet further to four or five. New START provides for further reductions in deployed launch vehicles, limiting the number of Submarine-launched ballistic missiles (SLBM) to 288, and the number of deployed SLBM warheads to a total of 1,152.

Submarines currently armed with Trident II missiles

 * USS Alabama (SSBN-731)
 * USS Alaska (SSBN-732)
 * USS Henry M. Jackson (SSBN-730)
 * USS Kentucky (SSBN-737)
 * USS Louisiana (SSBN-743)
 * USS Maine (SSBN-741)
 * USS Maryland (SSBN-738)
 * USS Nebraska (SSBN-739)
 * USS Nevada (SSBN-733)
 * USS Pennsylvania (SSBN-735)
 * USS Rhode Island (SSBN-740)
 * USS Tennessee (SSBN-734)
 * USS West Virginia (SSBN-736)
 * USS Wyoming (SSBN-742)
 * USS Wyoming (SSBN-742)


 * HMS Vanguard (S28)
 * HMS Vengeance (S31)
 * HMS Victorious (S29)
 * HMS Vigilant (S30)
 * HMS Vigilant (S30)