With an 18-metre-long Welsh Dragon attached to its bow, the Royal Navy's latest Type 45 destroyer, to be called HMS Dragon, was launched from BVT's shipyard at Govan into the Clyde on Monday 17 November 2008.

Dragon, the fourth Type 45 destroyer, will join her sister ships as one of the largest and most powerful warships in the world. As well as providing air defence over a wide area, including for the future aircraft carriers, the Type 45s will be highly versatile and able to conduct a variety of operations. They will be able to carry up to sixty Royal Marines Commandos and their equipment, and operate a Chinook-sized helicopter from the flight deck.

Complete with the latest upgrade to satellite communications systems, the destroyer will carry the world-leading Principal Anti-Air Missile System (PAAMS), allowing it to defend high value ships from the most dangerous air threats, including multiple attacks by sophisticated anti-ship missiles.

Subsequent vessels of a planned eight ship class (six ordered) are expected to follow at regular intervals between that point and around 2015.

The six T45 destroyers being built for the Royal Navy are in various stages of build, outfit, and trials:

• The first of class, Daring, successfully completed her final set of sea trials whilst in the contractor's hands and entered service in 2009.

• Dauntless, the second of the T45s, started her initial set of sea trials on 14 November 2008, for a period of four weeks.

• Diamond, the third, is being fitted out on the Clyde and will go to sea for the first time in the next 12 months.

• Dragon, the fourth, was launched on 17 November 2008 from Govan shipyard.

• The bow for the fifth T45, Defender, was rolled out at Portsmouth Naval Base in April 2008 and good progress continues to be made on her build.

• The steel cut for the sixth Type 45, Duncan, took place on 29 February 2008.

The current estimated unit production cost of each Type 45 is £561.6 million, based on the currently approved programme of six ships.

PRINCIPLE ANTI-AIR MISSILE SYSTEM (PAAMS)

This estimate includes the cost of the principal surface to air missile system (PAAMS), which is the primary weapons system for the Type 45 destroyer. Within the figure of £561.6 million overall cost, the cost of the PAAMS system is approximately one third or about £187 million.

In addition to its role as an air defence vessel the Type 45 destroyer will be a versatile platform that is planned to deliver a number of capabilities. These include naval gunfire support and, through its embarked helicopter, anti-submarine and anti-surface warfare.

It will be capable of employment in a full range of tasks including maritime force protection, interdiction and peace support operations. With eight Type 45 destroyers in service, a minimum of five units would be available to the Fleet for deployment at various states of readiness.

The vessel is powered by the WR21 Gas Turbine enabling her to reach speeds of up to 29 knots.