UGM-133 Trident II D5 Missile

Full Specifications

UGM-133 Trident II D5 SLBM Missile

The UGM-133 Trident II, also known as the Trident D5, stands as a cornerstone of U.S. strategic nuclear deterrence. This three-stage, solid-propellant submarine-launched ballistic missile (SLBM) provides a survivable second-strike capability from Ohio-class and future Columbia-class ballistic missile submarines.

Overview/Introduction

Introduced into service in 1990, the Trident II D5 delivers intercontinental reach with high accuracy against hardened targets. It forms the sea-based leg of the U.S. nuclear triad and is also operated by the United Kingdom under the Polaris Sales Agreement on Vanguard-class (and future Dreadnought-class) submarines. The system emphasizes reliability, with over 160 successful test launches recorded since design completion.

Manufacturer

Lockheed Martin Space (formerly Lockheed Missiles and Space Company) in Sunnyvale, California, serves as the prime contractor. Propulsion stages involve contributions historically from Hercules/Thiokol and United Technologies; current motor production is consolidated under Northrop Grumman in some accounts. The missile has undergone life-extension programs (D5LE) to maintain operational status into the 2040s and beyond.

Speed and Range

The Trident II reaches terminal speeds of approximately Mach 24 (about 18,030 mph or 8,060 m/s). Official range figures cite greater than 4,000 nautical miles (approximately 7,360 km) with a full payload of eight Mk-5/W88 warheads. Reduced payload configurations extend range to roughly 6,220 nautical miles (about 11,520 km). Maximum published estimates reach up to 12,000 km under lighter loads.

Cost/Price

The U.S. Navy lists a unit cost of $30.9 million in 1987 dollars (approximately $87–88 million in recent inflation-adjusted terms). This figure excludes warheads. Sustainment, life-extension, and production contracts continue, reflecting ongoing investment in the strategic weapons system.

Guidance relies on the Mk 6 astro-inertial system (inertial with stellar updates), achieving a reported circular error probable (CEP) of about 90–100 meters. The missile carries multiple independently targetable reentry vehicles (MIRVs) with W76 (approximately 90–100 kt) or W88 (475 kt) warheads, subject to treaty limits (typically up to eight). It launches from submerged submarines via gas-generator ejection before first-stage ignition.

The Trident II remains a key element of U.S. and UK strategic forces, supporting nuclear deterrence through survivability, accuracy, and range.