LÉ Róisín (P51)

LÉ "Róisín" (P51) is the lead ship of her class of offshore patrol vessel in the Irish Naval Service. The ship is named after Roisin Dubh, probably one of the daughters of Red Hugh O'Neill, Earl of Tyrone in the late 16th Century.

History

"Róisín" was built by Appledore Shipbuilders in Devon [http://www.naval-technology.com/projects/roisin/] , entered service with the Irish Naval Service in September 1999 and is based at the Haulbowline Island, Cork Harbour Headquarters and Dockyard.

Design

The ship has an all-steel hull based on the Mauritian Vigilant patrol vessel launched in 1995, but without the helicopter deck and hangar facilities. The high level of automation incorporated into the ship's systems allows the ship to be operated with just 47 crew including eight officers. The crew is provided with comfortable accommodation. The vessel is designed for winter North Atlantic operations.

Weapons systems

The ship is armed with an OTO Melara 76 mm gun installed on the bow gun deck. The gun fires 6 kg shells and is capable of firing up to 85 rounds per minute to a range of over 15 km. There are also two 12.7 mm machine guns.

The main gun is controlled by an Ultra Electronics Command and Control Systems, Radamec 1500 optronic director with a daylight TV camera, thermal imaging camera and eyesafe laser rangefinder. System 1500 functions in automatic or manual mode. The system provides fire control for surface engagement with spotting corrections in both line and range and has an effective secondary self-defence anti-air capability. System 1500 can detect a small patrol boat at ranges in excess of 12 km, night or day. The ship's Kelvin Hughes surface search radar, operating at E, F and I bands, is installed high on the main mast over the bridge. The Kelvin Hughes navigation radar operates at I-band.

Command and control

The communications package includes VHF, HF, Inmarsat Global Maritime Distress Safety System (GMDSS) and Differential Global Positioning System (DFPS) and secure communications. Three inflatable boats are deployed from each ship; two 6.5 m Delta rigid inflatable boats (RIB) launched with Caley davits, and a single Avon 5.4 m RIB.

Propulsion

The ship is powered by two Wartsila 16V26 diesel engines each developing 5,000kW continuous power. The engines drive two shafts with Lips inboard turning controllable pitch propellers via single reduction gearboxes. Each propeller is 2,500 mm in diameter and functions at 300 rpm.

The engines provide a maximum speed of 41 km/h (22 knots) with a range of 11,100 km (6,000 nautical miles) at a cruising speed of 28 km/h (15 knots).

A Brunvoll FU45 CPP bow thrusters, rated at 340 kW with 5.6 tonnes-force (55 kN) thrust, is fitted for precision manoeuvring and station keeping. A pair of non-retractable anti-roll fin stabilisers is also fitted.

Three Caterpillar 3412D1-T generators each deliver 405 kWe at 1,500 rpm. One Caterpillar 3406D1-T emergency generator delivers 205 kWe at 1,500 rpm.

Other

"Róisín" was involved in the rescue of the Canadian Forces submarine HMCS|Chicoutimi|SSK 879|2 off the northwestern coast of Ireland on 5 October 2004. As the "Róisín" attempted to assist the submarine she was seriously damaged by the rough seas and forced to return to harbour.

ee Also

*LÉ Niamh (P52)
*Protector class OPV RNZN

External links

* [http://www.akeryardsmarine.com/ship_patrol.html Web page from the naval architecture firm that designed IDF LÉ "Róisín"] .
* [http://www.military.ie/naval/flotilla/p51/roisin.htm IDF LÉ "Róisín" webpage]