Interview: Captain James Fuller, leading the heroes of the high seas

Today, he is making his way home aboard the HMS Ocean, the ship's future in doubt in the wake of Tuesday's Strategic Defence and Security Review. Ocean has just completed a five-month deployment protecting British interests in the Atlantic, helping to fight piracy and drug smuggling on the high seas, with Captain Fuller at the head of the team of six Royal Marines.

More than 130 seafarers are being held captive by pirates on the Somali coast, including British couple Paul and Rachel Chandler, who were kidnapped one year ago tomorrow and are still being held captive in the country.

Fuller, of Auchterarder in Perthshire, and his unit of highly trained specialist fighters are part of the embedded force on board Ocean and undertook a series of exercises off the coast of Somalia, where piracy and drug smuggling are big problems.

The combat hardened unit, from Fleet Protection Group (FPGRM) at Faslane on the Clyde, was formed to deal with the threat of outlaws who have hit shipping on sea lanes. Using fast boats, the highly mobile, specially armed team board and are ready to battle suspected pirates or drug smugglers. Wearing lightweight body armour and lifejackets and carrying knives, SA80 carbines and semi automatic pistols, Fuller's men have to search and secure each intercepted vessel.

In one assault, Fuller's team, the oldest of which is 31, leapt carrying their weapons from inflatable speed boats onto an armoured landing craft crewed by marines and cadets from the 21,000-tonne helicopter carrier's company.

Fuller said: "Increasingly now, piracy is becoming a problem in waters surrounding Africa, and the Royal Navy is constantly increasing its presence and trying to respond to such threats. Doing so also allows us to aid friendly countries, and further our skills when it comes to conducting boarding operations with other armed forces.

"It makes a good change from being stuck in a hole in the desert."

Despite the pressure and the risks he faces, Fuller insists he enjoys his dangerous duties. "It's quite a nice job to do," he says. "You get some good equipment, work with some interesting people. And it is always varied; you never know who you are going to be coming up against."

Such as boarding the boats of innocent fisher folk, whose responses to the unwelcome intrusion range from bemusement to hostility.

"Some of the fishermen are very colourful individuals," he admits. "The way they look at it is that it's an embuggerance for us to come on board; we are getting in the way of their daily activities, they are trying to get about their business so naturally, sometimes, they may step up their speed to try to stop us reaching them; that's when it becomes a non-compliant boarding."

Some do whatever they can to prevent anyone from getting aboard. It is at this point that the Royal Marine team is used as opposed to a Royal Navy team, which tends to be utilised when a vessel is very compliant and happy to help out. "In all fairness, it does not happen very often," says Fuller. "If you have something the size of Ocean bearing down on top of you and four helicopters flying overhead with weapons pointed at you, everyone's pretty compliant.

"You might get the odd person engaged in nefarious activities; criminals and such like, that will try to do anything within their means to get away – obviously the ship can't move as quickly as a small boat can, and if our drills aren't swept up enough and we aren't able to stop that boat in time, then that's where the threat gets raised."

Keith Blount, Ocean's commanding officer, said: "Piracy and the narcotics industry is a problem that is large enough to get the interest of governments all around the world, and certainly the Royal Navy working for the British government is engaged in counter narcotics and counter piracy pretty much round the clock.

"It is an important issue and one in which we play a crucial role in trying to drive it down."

The huge amphibious assault ship, which carries a crew of 370 men and women and an embedded force of up to 500 marine commandos, will return to Devonport, Plymouth, on Friday.

Its latest deployment has seen Ocean's crew of sailors and marines involved in daring counter-piracy exercises off the coast of Africa, as well as helping further British business and national security abroad.

Ocean has visited Rio de Janeiro in Brazil, Lagos, the former capital of Nigeria, Sierra Leone, the Cape Verde Islands and Portugal, as well as providing support to islanders as Hurricane Earl swept the Caribbean. However, under the Strategic Defence and Security Review, either Ocean or HMS Illustrious will be decommissioned following a short study of which provides the most effective helicopter platform.

Blount, however, plays down fears that the ship, which is due a multi-million pound refit next year, will be lost. Its latest mission, he says, has proved how important Britain's naval service is – and how Ocean is a vital part of the fleet, adding that he is tremendously proud to be captain of the 22,500-tonne ship.

"It's a long way from being an 18-year-old midshipman at Dartmouth 26 years ago to being in command of the Royal Navy's largest warship," Blount says. "But it's an exciting job. It's a job that has taken me all over the world and this is the pinnacle of it."

The warship was last week nearing port in Cape Verde, off the coast of West Africa, where she was due to participate in a series of war games, when an SOS distress call from a freighter in the middle of the Atlantic prompted her to alter course and switch the engines to full speed.

Ocean then embarked on a 350-mile mercy dash to save a sailor struck down by a life-threatening illness. The Italian-registered vessel Grand Guinea had reported a crew member was dangerously ill with suspected appendicitis. Ocean's doctor Anthony Gregory was able to speak to the ship by phone and confirmed the situation was grave. "It sounded serious," says Dr Gregory. "He had the textbook symptoms of appendicitis for 24 hours and it was getting worse. We needed to get him to a hospital quickly for surgery before his appendix burst."

As Ocean headed due west, Grand Guinea travelled east to meet her. An aircraft engineering technician was then winched down to the freighter's deck from a Royal Navy grey Lynx helicopter which had been stripped out to accommodate a stretcher. The Ocean then headed back to Cape Verde at full speed while the man was stabilised and given antibiotics before undergoing surgery to remove his appendix.

The Ocean has seen its fair share of excitement over the past 12 months but is now heading home for a well-deserved rest, but an uncertain future. From Cape Verde, the Ocean was heading to Lisbon before setting sail for Plymouth, where its fate awaits.