The upgrade and maintenance programme on the UK Royal Navy’s Type 23 frigate HMS Portland has begun at Babcock’s Rosyth dockyard in the UK.

The upgrade is aimed at maintaining the ship at peak effectiveness and follows the recent successful refits on other Type 23 frigates including HMS Kent.

The frigate refit task includes providing a new DNA(2) command system to enhance the ship’s fighting capability against air, surface and underwater threats, and a new defence information infrastructure (future) (DII(F)) to allow information-sharing across the network.

The ship will be fitted with Sonar 2087, a tactical, variable depth, active and passive anti-submarine warfare (ASW) system and the Seawolf mid-life update (SWMLU) to defend against anti-ship missile threats.

The company will also provide structural modifications to the aft end of the frigate, replace the 4.5 Mk8 Mod1 gun and equip the vessel with a 30mm automatic gun.

Additional enhancements include integration of Nato radial filters to protect fresh air supplies from contamination, and the nuclear biological chemical defence incident surveillance system.

Further upgrades will include providing flexibility of supply with a high-pressure air system, and galley equipment upgrades and habitability improvements.

The frigate will also undergo structural repairs, and maintenance of all systems and equipment, including renewal of the hull coatings.

The 133m-long HMS Portland has a displacement capacity of 4,900t, is capable of cruising at speeds of 30.8 knots, can accommodate a crew of 185, and can be equipped with Harpoon and Seawolf missile systems, guns and anti-submarine torpedoes.

The refit programme is scheduled for completion within an 11-month timeframe after which the frigate will undergo sea trials in autumn 2012.