HMS Activity (D94): The Cargo Ship That Became a U-Boat Killer

A Cargo Ship Interrupted

HMS Activity had one of the more roundabout starts to naval life of any ship on this list. She began at the Caledon shipyard in Dundee as Telemachus, a refrigerated cargo liner being built for the Alfred Holt Line, with construction under way from as early as 1940.

Before she could ever carry a single crate of cargo, the Ministry of War Transport requisitioned her in February 1941 and renamed her Empire Activity, and then in January 1942 the Admiralty took her over again, this time for conversion into an escort carrier.

Once converted she displaced 14,250 tons fully loaded, measured 512 feet 9 inches long with a 66 foot 6 inch beam, could manage 18 knots, and carried a crew of around 700 to operate up to ten aircraft, defended by a pair of 4-inch guns and a battery of 20mm Oerlikon cannon.

The result looked nothing like the escort carriers most people picture. Activity was only the second merchant hull converted into an escort carrier by a British yard, after HMS Audacity, and the British approach was quite different from the American one: a long, narrow steel flight deck of about 490 feet by 66, against the shorter, wider wooden decks of roughly 410 by 78 on the American-built ships. She had no catapult, one small lift right aft measuring 42 feet by 24, a stubby hangar 87 feet long, and four arrestor wires with a single crash barrier, which was half what the American carriers had. Twin screws off two Burmeister and Wain diesels gave her better handling than the single-screw American conversions, and 12,000 brake horsepower gave her 18 knots, which was quite enough for convoy work and nothing like enough for anything else.

A ship that had started life destined for the refrigerated meat trade ended up, a little over a year later, launching Swordfish biplanes against German submarines in the Arctic.

She was launched in her new form on 30 May 1942 and commissioned that autumn under her first captain, G. Willoughby, working up at Lamlash and sorting out teething problems at Rosyth before formally entering service.

She had three captains in three years: Guy Willoughby from her commissioning until April 1944, Captain C. Wauchope from May 1944 to May 1945, and Captain E. R. North of the Royal Naval Reserve for her last five months.

Her honours board is short and to the point: Atlantic 1944 and Arctic 1944. She had no motto at all, which for a ship converted twice before she ever floated feels about right.

Her early months were spent as a deck landing training carrier, teaching pilots the particular art of putting an aircraft down safely on a small, pitching flight deck, useful preparation work rather than combat, but essential all the same.

Deck landing training was not the soft option that phrase suggests. From 1 January 1943 she worked for Western Approaches Command, and trainee pilots flew out to her daily to practise putting Swordfish, Fulmars, Martlets and hooked Hurricanes and Spitfires onto a deck that was moving in three directions at once. In one stretch between March and June 1943 alone she lost five aircraft. Lieutenant E. L. Russell missed every wire on the first day, struck the bridge and went over the side, and was fished out by the plane guard. Three more went over the side and one burned out. A Fulmar missed the wires the other way and went off the bow. Every one of those pilots was learning the skill that kept convoys alive, and the ship existed to let them get it wrong somewhere survivable.

Into the Arctic

Activity's real war began properly in January 1944, when she embarked 819 Naval Air Squadron and joined the Second Escort Group for convoy duty. Through the opening months of that year she escorted a string of Atlantic and Gibraltar convoys, among them OS66/KMS40, ONS28, SL147/KMS38 and KMS43G, before her aircraft found their moment in the brutal, freezing waters of the Arctic convoy route.

The squadron is worth knowing about, because 819 had already had one of the great nights of the war. It formed at Ford in January 1940 as a torpedo reconnaissance unit flying Swordfish, and on the night of 11 November that year it was one of the four squadrons that put twenty-four of those biplanes over the Italian fleet at anchor in Taranto, the second wave of eight being led by one of 819's own officers. That raid, which is described in the article on HMS Ajax (22), crippled half the Italian battle fleet in a single evening and was studied very carefully in Tokyo.

The squadron was worn out by Malta and disbanded there in January 1941, reformed at Lee-on-Solent that October, spent a while attached to RAF Coastal Command, and by the spring of 1944 was aboard a converted refrigerated cargo liner in the Barents Sea. It was still flying Swordfish. The aircraft that had been obsolete-looking in 1940 was still obsolete-looking in 1944 and was still sinking submarines, because a Swordfish could get off a very short deck in filthy weather, fly slowly enough to see what it was looking at, and carry depth charges and rockets, which between them is the entire job description.

JW 58 was not a routine run. Forty-seven merchant ships left Loch Ewe on 27 March 1944, with the American cruiser USS Milwaukee travelling among them on her way to being handed to the Soviet Navy under Lend-Lease. Activity and HMS Tracker joined on the 29th. Between them the two ships now flew a mixed bag: Activity's 819 Squadron had three Swordfish and seven Wildcats, Tracker's 846 had twelve Avengers and seven Wildcats.

What happened next was, strictly speaking, an air battle rather than a submarine hunt. On 30 March two of Activity's Wildcats, flown by Lieutenant J. G. Large and Sub-Lieutenant R. K. L. Yeo, shot down a Junkers 88. The following day 819 destroyed two Focke-Wulf 200 long-range reconnaissance aircraft, and that evening Wildcats from both carriers accounted for a Blohm und Voss 138 flying boat. Another Bv 138 went down on 1 April. Killing the shadowers mattered more than killing the U-boats: without accurate reporting the waiting submarines never got the convoy's position, and a carefully prepared trap simply failed to close.

The U-boat came on 3 April. A Swordfish of 819 Squadron, LS373, flown by Lieutenant S. Brilliant with Sub-Lieutenant H. Chadwick and Petty Officer J. Perry, caught U-288 on the surface, came under heavy anti-aircraft fire and called for help. An Avenger and a Wildcat from Tracker joined in, and combined depth charge and rocket attacks sank her at 73 degrees 44 minutes north, 13 degrees 04 minutes east, south-east of Bear Island. Brilliant and Chadwick were awarded the DSC and Perry the DSM.

Aircraft from Activity also had a hand in attacks that damaged U-362, U-673 and U-990. Every one of the thirty-seven merchant ships reached Murmansk on 4 April without loss, and the return convoy RA 58, thirty-eight empty ships, made Loch Ewe on the 14th without incident. For a small ship carrying ten aircraft on a deck built for frozen meat, that is a considerable fortnight.

From the Arctic to the Far East

By August 1944, with the U-boat threat in the Atlantic and Arctic increasingly under control, Activity was redesignated a ferry carrier, switched from hunting submarines to transporting aircraft and personnel out to the Far East, arriving in Ceylon on 23 October 1944.

The ferry run itself was a proper voyage: Belfast to embark Avengers and the personnel of 854 Squadron, then Gibraltar, Alexandria and Aden, reaching Cochin in southern India on 7 October and Trincomalee on the 23rd. She came home with passengers, including two squadrons of aircrew who had left their Barracudas behind in India because the Pacific fleet had decided it wanted Avengers instead.

While en route to Sydney the following year, she came across one of several groups of survivors from the SS Peter Silvester, a merchant ship sunk by the German submarine U-862 on 6 February 1945 in what proved to be the last U-boat attack of the war in the Indian Ocean, and on 28 February rescued 20 of them, adrift for more than three weeks by the time Activity found them, a reminder that even a ship reassigned to ferry duty could still find itself doing properly lifesaving work far from any battle.

The ship she found survivors from was carrying an unusual cargo. Peter Silvester was an American Liberty ship on passage some seven hundred miles south-west of Fremantle with two thousand seven hundred tons of United States Army stores, a hundred and seven soldiers, and three hundred and seventeen mules standing in stalls built on her deck, bound for the mountains and jungle of the Burma campaign where nothing with wheels was any use at all. There were a hundred and seventy-five people aboard. U-862 hit her with salvo after salvo from twenty to five in the afternoon on 6 February 1945 and she broke in half.

Thirty-three died. The rest came out in four separate groups, and the arithmetic of their rescue is the reason this is worth telling. Fifteen were picked up by an American merchantman on 12 February. Ninety-two more, on six rafts and in a lifeboat, were found by an American frigate on the 13th. Activity came across the third boat on 28 February, twenty-two days after the sinking, and landed the twenty men in it at Fremantle on 2 March. The last boat, with fifteen aboard, was not found until 9 March, by an American submarine, after thirty-two days at sea. Four ships of two navies, spread across a month and several hundred miles of the Indian Ocean, for one sinking.

As for the submarine, U-862 had the most improbable war of any boat still at sea in 1945. She was a long-range Type IXD2 under Heinrich Timm, the only captain she ever had, and she is the only German submarine that ever operated in the Pacific Ocean. On Christmas Day 1944 she sank the Liberty ship Robert J. Walker off Sydney. She then went south of Tasmania, round New Zealand, and into the harbour at Napier at night without anybody noticing she was there.

Her ending is odder still. When Germany surrendered in May 1945 she was at Singapore, so on 15 July the Imperial Japanese Navy took her over and commissioned her as I-502, which made her one of the very few warships to serve two Axis navies in the same year. She surrendered again in August, this time to the British, and was towed out and scuttled in the Strait of Malacca on 13 February 1946. Activity, by then, was home and laid up, six weeks away from being sold back into the merchant trade.

She went on to support Operation Tiderace, the reoccupation of Singapore following the Japanese surrender, before finally returning home on 20 October 1945, her war, in all its unexpected variety, finally over.

Back to Where She Started

In a pleasing bit of symmetry, Activity's naval career ended much as it had begun: back in merchant hands. She was sold to Glen Line on 25 March 1946 and converted by Palmers Shipbuilding into the merchant vessel Breconshire, entering commercial service in September 1947, more than seven years after her keel had first gone down as a cargo ship interrupted by a war.

She spent the next two decades quietly earning her keep as an ordinary merchantman, remaining in service until April 1967, when she made her final voyage from Kobe to the scrapyard at Mihara in Japan, arriving on 24 April 1967 to be broken up.

It is a quietly satisfying shape for a career: a cargo ship taken away from her intended trade to help win a war in the Arctic, credited with a share in sinking one U-boat and damaging three more and rescuing 20 shipwrecked sailors along the way, before being handed back to commercial life to finish out her days exactly as she was originally meant to, just under a very different name.