The seas off the north of Scotland and around Orkney and Shetland can be unforgiving and, in the worst of weathers, will catch out even the largest of ships. The safety of mariners and sea users in the area is overseen by the Maritime and Coastguard Agency (MCA). The primary role of the Coastguard is initiating and coordinating search and rescue (SAR) missions. Their Maritime Rescue Sub Centre (MRSC) at Lerwick, Shetland's capital, coordinates rescue units operating in the often treacherous seas around the Northern Isles.

This centre, one of 19 run by the MCA, maintains a round-the-clock monitoring service of shipping and sea activity and coordinates search and rescue incidents by tasking units as needed. An emergency planning room at the Rescue Coordination Centre in Lerwick facilitates the handling of major incidents so that rescue units work together effectively and efficiently.

The MRSC operations room is staffed 24 hours a day throughout the year from a watch-keeping complement of 20 personnel. They can call on the Coastguard helicopter, the five lifeboats based in Orkney and Shetland, 33 auxiliary Coastguard teams, made up entirely of volunteers who undertake cliff rescue and coastal searches, as well as the purposebuilt emergency towing vessel (ETV).

ETVs are large anchor-handling tugs similar in design to those employed in the oil industry for rig support duties. The stationing of ETVs at various locations around the British Isles came about as a result of a disaster off Shetland. On 5 January 1993, the oil tanker Braer ran aground off Sumburgh Head at the southern tip of the Shetland Islands.

Emergency rescue services were called out, the 34 crew were airlifted off and two tugs began trying to putl the tanker away from the rocky coastline. But the tanker, with 619,300 barrels of oil on board, ran aground and began leaking its cargo.

Attempts to disperse the slick were mostly ineffective. However, as the light crude oil was easily broken up by the large waves, 70 per cent either evaporated or dispersed naturally.

The subsequent inquiry into the Braer disaster recommended that ETVs should be stationed in the major shipping lanes ready to assist large vessels should they get into difficulty. The MCA was given the responsibility of managing the ETVs that were based initially in the Dover Strait and the Minches, with a third vessel to providecover for the Western Approaches followed by a fourth for the Fair Isle Channel near Shetland.

The latest Coastguard ETV is Anglian Sovereign, which arrived in Shetland in September 2003 to take up duties on the Fair Isle station. She operates under the jurisdiction of the area's Coastguard controller Neville Davis and covers a nominal area of 100 nautical miles radius centred on Fair Isle.This includes the Fair Isle Channel, the Pentland Firth and the waters around Orkney and Shetland, but she can of course go further afield if required. The ETV operates with a crew of 11 who live on board for a month, followed by a month off. During the winter, while awaiting a call, the ETV is anchored in sheltered waters such as the bays off the northern end of the Orkney archipelago, as near to the centre of her operational area as possible. In the harsh winter weather, exposing the crews unnecessarily to severe sea conditions would be foolhardy.

Two of the ETV's primary roles are counter-pollution work and pollution prevention. With basic heavy towing equipment, she is able to tow tankers likethe Braer away from the rocky shore. This prevents such tankers grounding and polluting the coastline, avoiding a threat to human life and the environment.

The ETV also performs standby duties, provides passive escort to tankers and works with Shetland's lifeboats in search and rescue operations. The vessel's programme of activity in the summer, a time when fewer large vessels require assistance, includes surveying the shipping traffic going through the channel.

Another essential element in the operation of the Coastguard's rescue service is the Sikorsky SK-61N helicopter, affectionately known as Oscar Charlie.

Chartered to the MCA from Bristow Helicopters, she is staffed round-the-clock by a crew of four with different crews who work 24-hour shifts. In action, the helicopter is usually in the air for about an hour and a half in good weather. The main exercises undertaken involve lifting and dropping people onto all kinds of vessels, as this is the task which they perform most often when called out for real. One of the most essential pieces of equipment fitted to the aircraft is the dual hoist system.

One hoist is used for the majority of lifts with another as back up. To help when searching for persons in the water, a forward-looking infrared camera provides broadcast-quality infrared images and an extensive range of medical equipment is also carried.

The RNU's Severn class lifeboats at Aith and Lerwick form another vital piece of the SAR jigsaw in Shetland. Aith lifeboat Charles Lidbury, which operates at the RNLI's most northerly station, covers a huge area in some of the most treacherous waters in the United Kingdom. Just to reach the open sea involves a journey of five miles and most services last at least 10 hours. The Chartes Lidbury can potentially reach higher speeds than the station's previous lifeboat, but in the heavy swells of the North Sea the lifeboat often has to be throttled back from her top speed of 25 knots, particularly when encountering 15m waves, a not uncommon occurrence.

To support the lifeboat, the station has a modern new crew facility, which was formally opened in May 2003.The £320,000 purpose-built facility, designed around the ideas and needs of the lifeboat crew, provides dedicated training rooms together with changing areas and more space for the crew and support personnel. It also has an exhibition area with TV and video, details of the rescues performed since the station was established in 1933 and a history of the station, so it has become part of the Shetland tourist trail.

Lerwick lifeboat station, established in 1930, is perhaps best known for the exploits of Coxswain Hewitt Clark, who was awarded the Cold Medal for the service to the cargo vessel Green Lily on 19 November 1997. The lifeboat crew in the Severn class Michael and jane Vemon battled to reach the vessel in atrocious weather as tugs tried to stop it going aground. When the last tow failed, all hopes rested with the lifeboat. Hewitt manoeuvred the lifeboat towards the casualty in limited sea room, which was reduced with each passing minute.

Numerous attempts were made to put the lifeboat in a position where the survivors could be evacuated. Many attempts had to be aborted due to the violent motion of the seas, but whenever possible a survivor would be grabbed by the lifeboat's crew and hauled aboard. Each time an approach was made, the lifeboat was slammed against the hull of the casualty in 15m breaking seas and violent force 11 winds.

As the lifeboat came clear, with five survivors on board, a tug had managed to grapple the casualty's starboard anchor cable, and pulled her head round to sea so that the helicopter could lift the other 10 crew members off the ship. During this part of the rescue, helicopter winchman Bill Deacon was tragically lost as he tried to help those on the casualty. Later in the day, after the survivors had been landed, the lifeboat was taken as close as was considered prudent in the conditions. They found no sign of the winchman and had to abort the search due to growing darkness and floating debris being tossed around in the huge seas.

The dramatic service to the Green Lily sums up rescue work in the Northern Isles.

The terrible conditions that can often be encountered by lifeboat and helicopter crews are not uncommon in these waters, and the teamwork of all involved when called into action has to be of the highest order. Vessels large and small use these busy waters and all come under the watchful eye of the Coastguard controllers.

With ferries, cruise ships, tankers using nearby Sullom Voe, large fishing vessels, workboats and the numerous pleasure crafts are all potential users of the search and rescue network of the Northern Isles.Nicholas Leach is Deputy Editor of the international shipping magazine Ships Monthly.

The feature upon which this article is based, Shetland sea guardians', appeared in the December 2003 issue and is adapted here by kind permission of that magazine.Thanks to Neville Davis, Kieran Murray, Peter Leask, the crew of Oscar Charlie and Mark Clark..