The battle was the Royal Navy's last battleship action, against the last major surface threat to the fraught Russian convoy route between Scotland and Murmansk via Iceland. Each convoy had three layers of protection: a close escort of destroyers, intermediate cover by cruisers and the distant support of battleships of the home fleet, commanded by Admiral Sir Bruce Fraser. The Germans' occupation of Norway enabled them to threaten passing convoys with aircraft, U-boats and surface ships separately or simultaneously, which made the route uniquely dangerous for the allies even without the appalling weather.
Grand Admiral Karl Dönitz, commander of the German Navy, persuaded a reluctant Hitler in December 1943 to sanction a new surface foray against the Russian convoys. Rear-Admiral Erich Bey left the Altenfjord in north Norway in the Scharnhorst, escorted by five destroyers. Admiral Fraser had anticipated the move as he organised the distant cover for one westbound and two eastbound convoys aboard his flagship Duke of York. Intermediate cover was provided by Vice-Admiral Robert Burnett's three cruisers, including HMS Norfolk, on which Lieutenant-Commander Pollock was gunnery officer.
German aerial activity and a flurry of signals, deciphered at Bletchley Park, revealed that the Scharnhorst was about to come out and attack eastbound convoy JW 55B. Fraser raced eastward from Iceland. He hoped to catch the Germans between Burnett to the north-east and himself to the south-west while the threatened convoy was diverted away from the scene.
The cruisers sighted the Scharnhorst on the morning of December 26 and opened fire. Pollock's shooting was the best, enabling the Norfolk to score a few hits before the heavily armoured Scharnhorst, several knots faster, drew away for a second pass at the convoy. But Burnett remained between her and her target, leading to a second clash in which the Norfolk lost a gun turret.
None the less the cruisers conveniently caused the Scharnhorst to turn towards the Duke of York, approaching at top speed. Fraser's flagship sighted her just after 4pm. He surprised the Germans when he opened fire at six miles, the start of a big-gun duel that lasted 90 minutes. A torpedo attack by destroyers finally slowed the Scharnhorst sufficiently to enable the Duke of York and the cruisers to surround her and hammer home their final salvoes. Only 36 out of nearly 2,000 German sailors survived.
Pollock was born in Altrincham, Cheshire, in 1916, into the family of a civil engineer. He went to Dartmouth as a naval cadet in 1930. After war broke out in 1939 he was appointed first lieutenant of a destroyer covering military convoys. He spent most of the war in convoy protection, becoming a gunnery specialist in 1941. As gunnery officer on the cruiser Arethusa he earned a mention in dispatches for gallantry when his ship was damaged by a German dive-bomber near Malta. His next appointment was to the Norfolk, where he earned another two "mentions" as well as the DSC.
After the war Pollock saw service in the Korean war and Malaya. He had a leading role in organising the state funeral of King George VI in 1952, for which the Queen personally made him a lieutenant in the Royal Victorian Order. By 1963 he was captain of the aircraft carrier Ark Royal, where he oversaw sea trials of the new Harrier jump-jet.
Rear-Admiral Pollock's last seagoing appointment was second in command of the Home Fleet. His flagship was the cruiser HMS Tiger, on which he supervised the abortive talks between the Rhodesian rebel leader Ian Smith and prime minister Harold Wilson in 1966.
In 1968 he was unexpectedly appointed flag officer submarines, an increasingly important branch of which he had no experience. During his brief tenure, Polaris submarines took over responsibility for the British nuclear deterrent from the RAF's V-bombers. Pollock's next appointment, as controller of the Navy, in charge of ship design and construction, in 1970 was no less sensitive. The navy was embroiled in reshaping the fleet, withdrawing from a worldwide role to concentrate on the north-east Atlantic, and abandoning carriers.
This appointment was cut short by the sudden death of the outstanding first sea lord of the day, Admiral Sir Michael Le Fanu, just as he was about to become chief of defence staff. He was replaced by Admiral Sir Peter Hill-Norton, which meant that a new first sea lord had to be found. Pollock, to his own surprise, was given the job. His three-year term was the opposite of a gentle progress to retirement, embracing as it did the Icelandic "cod war", the 1974 oil crisis and deep cuts in defence expenditure, although he helped to ensure that the Invincible-class carriers, emolliently styled "through-deck cruisers" and still the pride of today's fleet, were built.
When he retired from active service in 1974 with the GCB, he undertook ceremonial tasks for the Order of the Bath and indulged his interests in walking, shooting, fishing and local affairs in Powys. His first wife, Margaret Steacy, whom he married in 1940, died in 1951. Three years later he married Marjory Reece, who died in 2001.
His two sons and daughter of the first marriage, and the stepdaughter of the second, survive him.
· Sir Michael (Patrick) Pollock, sailor, born October 19 1916; died September 27 2006