Andy Hutchinson, who is thought to have been one of the oldest surviving submariners to have taken part in the Second World War, has died at the age of 93.
He attended the Remembrance Day service in Belfast last Sunday, and passed away peacefully two days later.
He was a keen member of the Submariners' Association and regularly attended their Northern Ireland branch meetings until recently.
He was born and brought up in Belfast, and at the age of 16 he signed up with the Submarine Service, one of the most dangerous roles in the Armed Forces, where there was only a one in three chance of survival.
In 1943 he served in HMS Valkyrie, the Radar Training School in Douglas, Isle of Man. The next year he served in HMS Dolphin, and from June to August that year in HMS Cyclops.
Then from 1944 to 1946 he served in the submarine HMS Sportsman.
Mr Hutchinson told friends later that he always thought of the time when he was on deck and came under fire from a German Stuka dive bomber, being wounded in the leg by a ricocheting bullet.
His life was saved by a comrade who pushed him to safety down the hatch of the submarine, but unfortunately his rescuer was killed.
His longest uninterrupted service was on the HMS Sportsman, in the Mediterranean and the Atlantic, where his vessel sank 12 enemy ships and survived numerous attacks from the Germans.
The Germans used U-boats to devastating effect during the Battle of the Atlantic, where they tried to cut off the UK's supply routes by sinking more merchant ships than Britain could replace.
The Battle of the Atlantic, which until recently was commemorated by annual church services in Belfast and elsewhere in Northern Ireland, was one of the most crucial battles which the Allies had to win, and while U-boats destroyed a significant number of ships, the German strategy ultimately failed, in no small part due to the courage of the crews of the merchant vessels.
By the end of the Second World War almost 3,000 Allied ships had been sunk by U-boats in various theatres of conflict.
A significant number of surrendered U-boats were moored in the naval base at Londonderry.
Apart from the important role in the Atlantic, the Royal Navy Submarine Service blockaded trade and military supply routes to Africa and the Far East.
On one occasion Mr Hutchinson and his colleagues suffered a "blue on blue" attack by American forces, which led to considerable damage and serious injuries.
His submarine took part in an operation that involved dropping agents from the Special Boat Service into Italy and France.
One of his memorable journeys was from the Mediterranean to Scotland, and then to St John's in Canada and Philadelphia in the USA, where he trained in sonar and radar technology before returning to the UK.
He also had a frightening experience when his submarine captain ordered a test dive, which saw the vessel suffer a mechanical failure and sink below crush depth.
However, he and his colleagues fortunately survived to tell the tale.
Mr Hutchinson's funeral service will take place this Thursday in Knockbreda Methodist Church at 11.30am, when the standard of the Northern Ireland branch of the Submariners' Association will be paraded.
It will be followed by cremation at Roselawn at 1pm.