HMS Ultimatum (P34): Sinking a Submarine Off Calabria

Laid Down at Barrow

HMS Ultimatum was built by Vickers-Armstrongs at Barrow-in-Furness, her keel laid on 19 June 1940, launched on 11 February 1941 and commissioned on 29 July 1941 under Lieutenant Peter Robert Helfrich Harrison, a second-group U-class submarine that went on to fight nine demanding patrols out of Malta's 10th Submarine Flotilla.

One thing to settle before going any further: for the whole of the war she fought under her first captain, she was not called Ultimatum. She was P34. In 1940 the Admiralty had dropped submarine names in favour of pennant numbers, on the reasoning that a number gives an enemy nothing, and every boat of this generation spent its early career as a set of digits. The name arrived in 1943, and who chose it is worth waiting for.

What she was is easier to describe. The U class were small, cheap and slow: about 191 feet, a crew of roughly thirty-three, four torpedo tubes in the bow and a top speed on the surface that a decent trawler could match. They had been designed as unarmed training targets and were pressed into a shooting war because they were the boats Britain actually had. In the narrow, shallow, brilliantly clear central Mediterranean this turned out to be an accident of the best kind, because a small submarine is a hard submarine to find. HMS Uproar came from the same batch of sixteen.

The 10th Submarine Flotilla she fought from was the most dangerous posting in the Royal Navy submarine service, and one of the most productive. Working out of Malta while the island was being bombed around them, its boats cut the supply route to Rommel's army in North Africa and were killed doing it at a rate that would have closed down most organisations. HMS Upholder sank more tonnage than any other British submarine of the war and did not come back. Neither did HMS Urge, whose wreck was not found until 2019. P34 came back.

A Productive Winter

On 25 January 1942, Ultimatum sank the Italian passenger ship Dalmatia L. south-west of Cape dell'Armi, and on 14 March that year sank the Italian submarine Ammiraglio Millo off Punta Stilo in Calabria, a truly significant success against an enemy underwater adversary within just seven weeks of her earlier sinking.

Fourteen Men Off Punta Stilo

The attack itself was quick and well judged. At 1255 on 14 March 1942 Harrison saw a conning tower about eight thousand yards off, tracked it for twenty-four minutes, and fired four torpedoes from 2,200 yards. Two hit. The Ammiraglio Millo, a large ocean-going boat of a type built to work the Atlantic and lately reduced to running supplies, went down off Punta Stilo with most of her company.

What happened next rarely gets told, and it is the part worth knowing. At 1325, six minutes after the Millo sank, Harrison surfaced. He was in daylight, a few miles off the Calabrian coast, in water the Italian navy and air force patrolled constantly, in a submarine whose entire defence was not being seen. He stayed on the surface long enough to pull fourteen Italians out of the sea: four officers and ten ratings.

Then he had to put them somewhere. A U-class boat has no spare volume at all. Thirty-three men already lived in a steel tube where the bunks are slung between the torpedo tubes and nobody has a private inch, and Harrison had just added fourteen more, soaked in fuel oil, who had watched their shipmates drown and had every reason to be dangerous. He turned for Malta rather than continue the patrol, and landed them there on 16 March.

It is worth being clear that nothing obliged him to do any of it. Submarines were not generally expected to stop, and a great many did not, because surfacing to rescue survivors is the most efficient way yet devised of getting a submarine killed. Sinking another submarine was a rare enough achievement on its own, and HMS Telemachus shows how the same feat usually ended, with the survivors left in the water for somebody else to find. Doing it and then staying up top to fish them out is rarer still.

She also attacked Italian convoys on 5 December 1941 and 23 February 1942, though the results of the latter attack, against three modern merchant ships escorted by seven destroyers, remained uncertain.

Later Wartime Service

Under Lieutenant Hedley Kett from January 1943, Ultimatum continued operating in the Mediterranean, attempting an attack on the German U-boat U-73 off Toulon on 30 October 1943 without success, before shelling Kalamata harbour in Greece on 2 May 1944, sinking two sailing vessels, destroying five more still on the slips, and sinking the German barge F 811, a notably thorough piece of harbour harassment.

The Man Who Named Her

Hedley Kett is the answer to the question left hanging earlier, and he is one of the more unlikely people to have commanded a British submarine. He was not a career naval officer. Born at Ponders End in the Lea Valley in July 1913 and brought up in Blackheath, he went to sea in 1929 as a deck apprentice in the merchant service with the Bolton Steamship Company, aged sixteen. He came into the Royal Fleet Auxiliary when the tanker he was serving in was chartered by the Admiralty during the Spanish Civil War, and took a Royal Naval Reserve commission in 1938.

His first command was about as far from glory as a command gets. P-555 spent her days off Tobermory acting as what the trade called a clockwork mouse: a live submarine for surface ships to practise hunting, going where she was told, being found on purpose, over and over. Then in January 1943 he was given P34, and Churchill had by then overruled the Admiralty and ordered that submarines have names again, on the grounds that men will not fight a number. Some boats were named by the Prime Minister himself, as HMS Tiptoe was. This one was named by her captain, and the word Kett chose was Ultimatum.

He kept her for two years, longer than any of her other eight commanding officers, and took her north of Iceland to work up before settling into a further twelve Mediterranean patrols of his own, on top of the nine she had already fought from Malta under Harrison. The Kalamata shoot belongs to the end of that stretch. By 1944 there were almost no worthwhile targets left at sea in the Aegean, so submarines went in after what was left: a submarine on the surface inside a defended harbour, firing a three-inch gun at sailing vessels on the slips, is a boat that has run out of anything better to shoot at.

Kett came out of it with a DSC and Bar, went back to the merchant service he had started in, and was demobilised in 1946 with a licence as a London and North Sea pilot. He spent the rest of his working life putting other people's ships up the Thames and into Harwich. He was appointed ADC to the Queen in 1966, sworn in as a Younger Brother of Trinity House in 1971, and died at the age of a hundred.

The End of Her Service

HMS Ultimatum was sold to be broken up for scrap on 23 December 1949 and was scrapped at Port Glasgow in February 1950, closing out the career of a submarine whose Mediterranean war had ranged from passenger liners to enemy submarines to a harbour full of stranded sailing vessels.

She lasted rather longer than the war she was built for, and did nothing much with the extra time. A U-class boat had no future in a post-war navy: too small, too slow, too short-ranged, and designed in the first place to be a target. Nine years after the Millo she was sold, and in February 1950 she was cut up at Port Glasgow. The name has not been used since, which seems a pity for a word that was picked out not by a committee in London but by the man who then had to take the boat to sea and answer for her.