The US Navy has completed a series of test flights of Trident II D5 missiles from an Ohio-class ballistic missile submarine that is assigned to Submarine Group 9.

The follow-on commander's evaluation test (FCET) involved four Trident II D5 missile tests over a period of three years.

The tests were conducted to obtain valid reliability, accuracy, and performance of the missile system for use by Commander, Strategic Command and the Joint Chiefs of Staff, under operationally representative conditions.

During all the four test firings from the sea, the unarmed missiles flew over the sea and landed in the sea.

At no time did the missiles fly over land, the US Navy stated.

The Trident II D5 missile is part of the US strategic deterrent triad and is said to be an effective nuclear deterrent for national security and the security of US allies and friends.

This submarine-launched ballistic missile provides the national command authority with assured second-strike capability, according to the statement.

Since its introduction to the fleet in 1989, the Trident II D5 missile has completed 165 successful test flights.

In addition to Ohio-class submarines, the Lockheed Martin-built fleet ballistic missile is currently aboard British Vanguard-class submarines.

The three-stage, solid-propellant, inertial-guided ballistic missile can carry multiple independently targeted re-entry bodies for a maximum range of over 7,360km.

Image: A Trident II D5 ballistic missile launch from an Ohio-class ballistic missile submarine during a missile test at the Pacific Test Range. Photo: courtesy of US Navy photo/Released.