HMS Alisma (K185): Built for France, Fought for Britain

Built for One Navy, Delivered to Another

HMS Alisma began her life under an entirely different flag. The French Navy had ordered a batch of anti-submarine corvettes from British and French yards in April 1940, including six built by Harland and Wolff in Belfast, and one of these was intended as the corvette Pertuisane.

France fell to Germany that June, before her keel was even laid, and by the time work began at Belfast that August she was completed for the Royal Navy instead, rearmed with British guns and renamed in keeping with the Flower class's tradition of flower names. Alisma was commissioned on 14 February 1941, a fairly literal example of one country's wartime misfortune becoming another's useful asset.

All six of the Belfast corvettes went the same way, and there is a sharp little symmetry in what happened to the rest of the French order. The six ordered from Harland and Wolff in April 1940 were completed for the Royal Navy as Abelia, Alisma, Anchusa, Armeria, Aster and Bergamot. Six more had been ordered from yards in France itself in December 1939. Two of those were cancelled and the other four were still on the stocks when the Germans arrived, and were finished and used by the Kriegsmarine.

So the same design, ordered by the same navy in the same year, produced six ships that spent the war escorting Atlantic convoys against U-boats and four that spent it working for the people running the U-boats. Which side a corvette ended up on depended entirely on which side of the Channel her keel happened to be lying on in June 1940.

It is worth knowing where the design came from, because it explains almost everything about her. The Flower class began as a whale catcher. Smiths Dock of Middlesbrough offered the Admiralty an enlarged version of their own Southern Pride, a 700-ton, sixteen-knot boat built for chasing whales in the Southern Ocean, stretched by thirty feet and fitted with fire-tube boilers that a jobbing yard could turn out in sixteen weeks rather than the seven months a proper water-tube plant demanded. That was the entire point. The ships could be built by firms that had never laid down a warship in their lives, and hundreds of them were.

The price was paid by the men aboard. A Flower rolled with an enthusiasm that has to be read about to be believed, complete rolls of eighty degrees, forty each side of upright, being unremarkable in an Atlantic winter, and the standing joke in the escort forces was that a corvette would roll on wet grass. She was also, at sixteen knots, marginally slower than a Type VII U-boat running on the surface, which meant a corvette could never actually catch one. She could only find it, keep it under and keep it away from the convoy, which turns out to have been what mattered. Her armament was a single 4-inch gun on the forecastle and a great many depth charges.

The name she nearly had is worth a moment. A pertuisane is an old French polearm, a partisan or half-pike, and the French Navy had been naming this batch after edged weapons while the Royal Navy was naming its own after garden plants. Alisma is water plantain, which grows in ditches. Two navies, the same hull, and about as different a set of instincts as you could ask for.

Into the Convoy War

Alisma's very first taste of the Atlantic war came within weeks of commissioning, when she joined the escort for Convoy HX 115 as it neared Britain in late March 1941, only for the German submarine U-48 to sink three of its merchant ships, Hylton, Germanic and Limbourg, before it reached safety.

The submarine that ruined her first convoy was no ordinary opponent. U-48 finished her career as the most successful U-boat of the entire Second World War, credited with fifty-one ships and something over three hundred thousand tons, sunk in barely two years under three different commanders. She was withdrawn to a training flotilla in the Baltic in mid-1941 on the grounds that she was technologically out of date, which says a good deal about how quickly that war moved. Alisma met her three weeks into her own career.

She spent her early service with Escort Group 1, and in the summer of 1941 helped defend Convoy ON 69, a formation of 26 merchant ships, against a determined attack by eight U-boats and two Italian submarines between 19 July and 1 August, an intense introduction to the realities of convoy escort work.

On 14 January 1942 she pulled six survivors from the water after the merchant ship Empire Surf was torpedoed by U-43, the first of several rescues that would punctuate her wartime service.

From 1942 into 1943 she served with the celebrated Escort Group B7 as part of the Mid-Ocean Escort Force, protecting convoys across the most dangerous stretch of the North Atlantic, the mid-ocean gap beyond the range of shore-based aircraft where U-boat wolfpacks did their worst work.

That posting put her, in the first week of May 1943, in the middle of the most important convoy battle of the entire war, and it is worth stating plainly because her presence in it is easy to miss. Escort Group B7 at that point consisted of the destroyers Duncan and Vidette, the frigate Tay, and five corvettes: Alisma, Loosestrife, Pink, Sunflower and Snowflake, all under Commander Peter Gretton in Duncan. The convoy was ONS 5, forty-odd slow merchantmen going west, and over about a week they were attacked by three separate U-boat groups, Star, Amstel and Fink, in what became the largest convoy action ever fought.

The convoy lost thirteen ships. The Germans lost six submarines, at least four of them to B7: U-192 to Pink's depth charges on 5 May, U-638 to Loosestrife the same night, U-125 rammed by Oribi and then shot to pieces by Snowflake on the 6th, and U-531 caught between Snowflake's charges and Vidette's Hedgehog. Seven or eight more U-boats went home damaged. It is generally reckoned the turning point of the Atlantic campaign, and the full account of it is given in the articles on HMS Pelican (F86), who sank U-438 on the 6th, and on HMS Snowflake, who made ten separate attacks and had six torpedoes fired at her.

Alisma sank nothing at ONS 5, which is exactly why she is worth mentioning. Most of the ships in that battle sank nothing. What they did was stay between thirty-odd U-boats and forty-odd merchantmen for a week, in fog and gale, running down every contact, forcing every boat that showed itself to dive, and refusing to be drawn off. The four kills belong to four ships. The result belongs to all seven, and to the men in a Belfast-built corvette that had been ordered by a country which no longer had a navy, rolling forty degrees each way in the North Atlantic under an Australian reservist.

She was present for the loss of three ships from Convoy ON 153 in December 1942, and went on to take part in a punishing string of convoy battles around ONS 20, ON 206, ON 207 and ON 208, engagements in which her escort group collectively accounted for nine U-boats destroyed, a particularly formidable record for a group of small, unglamorous corvettes and their consorts.

Nine U-boats in a few weeks was not luck, and it is worth saying why the numbers turned over so completely. By the autumn of 1943 the escorts had high-frequency direction finding to fix a U-boat the moment it transmitted, centimetric radar that could pick up a periscope, and Hedgehog to throw a pattern of contact-fused bombs ahead of the ship instead of rolling depth charges off the stern and hoping. Above all, the mid-ocean air gap had been closed by very long range Liberators and by escort carriers sailing with the convoys. The wolfpack tactic depended on being able to gather on the surface in daylight, unobserved. Once that stopped being possible, the arithmetic of the whole campaign inverted inside about six months.

Under Australian Command

Alisma was commanded for almost her entire career by two Australians: Acting Lieutenant Commander Maurice George Rose of the Royal Australian Navy Volunteer Reserve, who took her to sea from January 1941 to May 1943, and Lieutenant George Lanning, who then remained in command from May 1943 right through to her decommissioning in June 1945, a reminder of just how thoroughly the Commonwealth contributed manpower and leadership to the Battle of the Atlantic, often in ships that had started out being built for someone else's navy entirely.

South, Then Home Again

From autumn 1943 through to April 1945, Alisma moved to the Mediterranean, escorting KMS and MKS convoys between Britain, Gibraltar and Mediterranean ports.

On 1 October 1943, while escorting Convoy MKS 26, she pulled 51 survivors from the water after the German submarine U-410 sank the merchant ship Empire Commerce, and helped rescue a further 68 men from the freighter Fort Howe, sunk in the same attack, easily the busiest single day of lifesaving in a war that had already asked a great deal of her.

She returned to the North Atlantic for her final months of service, escorting convoys on the Liverpool to New York run right through to the end of the war.

A Restless Retirement

Alisma was decommissioned on 11 June 1945 and sold in 1947, converted into a small merchant cargo vessel with diesel engines replacing her original steam machinery. She entered civilian service in 1949 under Panamanian registry as Laconia, before being bought by Greek interests in 1950 and renamed Constantinos S., and sold again in 1952 as Parnon.

Her merchant career, much like her wartime one, seemed unable to settle on a single identity for long.

It finally ended on 16 July 1954, when, carrying a cargo of ammonium sulphate from Marseille to Eleusis, she began taking on water and sank southwest of Naples.

There is a certain symmetry in how she finished. A hull drawn from a whale catcher, built by a yard that mostly built liners, ordered by one navy, commissioned by another and commanded throughout by Australians, went back to trade the moment the war stopped needing it, changed its name three more times, and eventually filled up and sank off Naples with a hold full of fertiliser. The war was the interruption. The merchant work was what the shape was always for.

A ship that had survived some of the fiercest convoy battles of the Battle of the Atlantic, under a flag she had never originally been built for, was ultimately lost not to any enemy but to a simple, unglamorous leak, nine years after the war that had defined her had already ended.