HMS Swale (K217): Two U-Boats Sunk Guarding the Atlantic Lifeline

Built on Teesside

HMS Swale was built by Smiths Dock Company at South Bank-on-Tees, laid down on 19 August 1941, launched on 16 January 1942 and commissioned on 24 June that year, a River-class frigate named for the Yorkshire river and destined for the long, gruelling work of Atlantic convoy escort.

Her first major test came almost as soon as she commissioned: that October, Swale escorted the Operation Torch convoys KMS 1 and KMF 1 from Loch Ewe towards North Africa, the convoy splitting in two off Gibraltar on 4 November to slip separately into Oran and Algiers just ahead of the actual landings, a baptism of fire that had her supporting one of the largest amphibious operations of the war before she had even seen her first winter afloat.

The River class deserves a word, because Swale belongs to the first type of ship the Royal Navy ever designed specifically to escort convoys across an ocean. The Flower-class corvettes that preceded them were an emergency measure adapted from a whale catcher, cheap and immensely seaworthy and utterly miserable, and, crucially, short of the endurance and the speed to work in the middle of the Atlantic rather than at either end of it. Smith's Dock, the same yard that had produced the Flower, drew the answer: a longer twin-screw hull with the range to cross from Newfoundland to Ireland without refuelling, enough speed to get back into station after a hunt, and room for the radar, the depth charges and the people to work them. They were called frigates, a word the Navy had not used for a century, and they arrived at exactly the right moment. HMS Tay (K232) is another of them.

Weathering Convoy SC 122

In March 1943, serving as Senior Officer's ship for Escort Group B5 under the overall command of Commander R.C. Boyle in the destroyer HMS Havelock, alongside the American destroyer USS Upshur and the Flower class corvettes Buttercup, Godetia, Lavender, Pimpernel and Saxifrage, Swale shepherded the slow convoy SC 122 from New York to Liverpool through some of the worst conditions the Atlantic could offer. A violent storm forced ten of the convoy's 51 merchant ships to turn back before the U-boats even arrived, and the sustained attack that followed cost eight more, part of the same vast running battle, fought alongside the parallel convoy HX 229, that historians still rank among the largest convoy actions of the entire war.

The Four Days When It Nearly Went Wrong

The battle around SC 122 and HX 229 is not merely among the largest convoy actions of the war; it is the largest, and it is the one the Admiralty came closest to losing. Over four days in the middle of March 1943, in the air gap in the middle of the Atlantic where no land-based aircraft could reach, three wolfpacks totalling thirty-eight U-boats got in among two convoys defended by about seventeen escorts. Twenty-two merchant ships were sunk, thirteen out of HX 229 and nine out of SC 122, something like a hundred and forty-six thousand tons, and more than three hundred merchant seamen were killed. One U-boat was lost.

That exchange rate is what frightened people. German radio called it the greatest convoy battle of all time and for once was not exaggerating; the Royal Navy's own official history, written afterwards by men who had been there, says flatly that defeat stared the Allies in the face. Serious consideration was given in the Admiralty to whether convoy itself, the whole basis of maritime strategy for four hundred years, had finally been beaten. Swale was in the middle of it as senior officer's ship of the escort group, having already lost ten of her charges to a storm before a single torpedo was fired.

What makes it bearable in retrospect is what happened next, and how fast. SC 122 was the last great convoy battle. Within eight weeks the very long range aircraft had closed the air gap, the support groups were at sea, and the U-boat arm lost forty-one boats in the month of May and withdrew from the North Atlantic altogether. The convoy that marks that reversal, ONS 5, is described in HMS Snowflake (K211). Two months separate the worst week of the Atlantic war from the week it was won.

Sinking U-657 off Greenland

On 17 May 1943, under the command of Lieutenant Commander John Jackson, Swale sank the German submarine U-657 off Cape Farewell, Greenland, while escorting convoy ONS 7 to Halifax, a submarine that had recently torpedoed the steamer Aymeric, making this a properly satisfying kill for her crew.

Rescue Under Air Attack

That July, Swale took part in the defence of Convoy Faith, rescuing survivors and assisting damaged vessels during sustained attacks by German Focke-Wulf aircraft, exactly the kind of dangerous, unglamorous rescue work that rarely made headlines but saved countless lives across the Atlantic campaign.

A Second U-Boat Kill

On 6 April 1944, Swale sank U-302 with depth charges while escorting convoy SC 156 from Halifax to Loch Ewe in Scotland, after the submarine had penetrated the escort screen and sunk the Norwegian merchantmen Ruth I and South America, bringing her confirmed U-boat tally to two.

A Spell Under the South African Flag

Lieutenant Commander John Jackson, who had commanded Swale since before she even commissioned and remained in charge for both U-boat kills, handed over to Acting Lieutenant Commander Patrick Varwell Collings in July 1944. Under her new captain, Swale's war finished a very long way from the Atlantic: in February and March 1945 she escorted Force 62 during Operation Stacey, a photographic reconnaissance mission off Sumatra and Penang in the Indian Ocean, about as different a posting from a North Atlantic gale as the Royal Navy could offer.

Operation Stacey was rather more than a photographic trip. In early 1945 the plan for retaking Malaya, Operation Zipper, required something nobody had: modern, detailed, low-level photographs of beaches, approaches and defences along the Kra Isthmus, Penang and northern Sumatra, taken from an angle that would show what a landing craft coxswain would actually see. So a carrier force went in and flew them, with the fleet escorting, in waters where the Japanese still had airfields. The photographs were duly obtained; the landings they were taken for were overtaken by the atomic bombs and the surrender, and the invasion went in unopposed in September as an occupation instead. HMS Empress (D42) was one of the carriers doing the flying.

Swale was loaned to the South African Navy on 26 June 1945, serving as HMSAS Swale until she returned to the Royal Navy in January 1946. She was finally scrapped on 26 February 1955, closing out the career of a frigate whose two confirmed U-boat kills stand as a genuine, hard-won contribution to winning the Battle of the Atlantic.