HMS Implacable (R86): From Hunting the Tirpitz to Striking the Japanese Home Islands

Built on the Clyde

HMS Implacable was built by Fairfield Shipbuilding at Govan, her keel laid down on 21 February 1939, launched on 10 December 1942 by the future Queen Elizabeth the Queen Mother, and commissioned on 28 August 1944, the lead ship of the Implacable-class fleet aircraft carriers.

She displaced 32,110 long tons at deep load, measured 766 feet 6 inches overall, and could reach a brisk 32.5 knots, carrying up to 81 aircraft and armed with eight twin 4.5-inch dual-purpose gun mounts alongside extensive anti-aircraft armament, with a crew of around 2,300 officers and ratings.

The five and a half years between her keel being laid and her commissioning are worth explaining, and so is what the delay did to her. Britain laid her down in February 1939 and then spent most of the war building other things: escorts, merchant repairs, landing craft, anything that would keep the Atlantic open, and a big fleet carrier that would not be ready for years went to the back of the queue more than once. While she sat there the design was reworked. Implacable and her sister were given an extra turbine and shaft for more speed, thicker hangar side armour, and a lower hangar stretched forty-six feet further forward than Indomitable's, all of which had to be paid for in weight. It was paid for by taking two feet out of the height of the lower hangar, so that both her hangars ended up with fourteen feet of clearance. That decision, made on paper to balance a displacement figure, defined the rest of her life.

Fourteen feet does not sound like a constraint until you try to put an aeroplane under it. The Vought Corsair, the best carrier fighter the Allies had by 1944, would not go into her hangars at all even with its wings folded; nor would a great many of the aircraft and, later, the helicopters that came after it. Hellcats were not available in the numbers required, so Implacable went to war with Seafires, which were beautiful aeroplanes, marvellous to fly and quite unsuited to carrier operations: narrow-tracked undercarriages that broke on hard landings, poor forward visibility over the nose in the approach, and a combat radius so short that a Seafire on patrol could not go far from the ship. Her accommodation was cramped for the same reason, since every foot taken out of a hangar has to come out of the deck below it, and she carried around 2,300 people. She was a fast, well-protected, heavily armed carrier operating the wrong fighters out of a hangar that was too short, because of a sum done in 1940.

Hunting the Tirpitz

HMS Implacable's very first mission, undertaken barely two months after commissioning, saw her sail from Scapa Flow on 16 October 1944 with 21 Barracudas of 828 and 841 Squadrons and 11 Fireflies of 1771 Squadron, part of the Royal Navy's long and determined campaign to neutralise the German battleship Tirpitz, one of the most powerful and dangerous ships in the German fleet. Her aircraft found Tirpitz two days later, anchored off Håkøya Island near Tromsø, but with no fighter escort of her own and Luftwaffe airfields close at hand, Implacable's air group had to break off without pressing home an attack, a frustrating anticlimax to her very first operation.

The Tirpitz campaign she joined at the end deserves setting out, because it had been going on for two and a half years and the Fleet Air Arm never quite managed it. Tirpitz did almost nothing for most of the war, and that was the point: as long as she existed in a Norwegian fjord, the Home Fleet had to keep a battle squadron in northern waters and every Russian convoy had to be covered against the possibility that she might come out. The Navy attacked her with midget submarines in September 1943, and then with carrier strikes through 1944, Operation Tungsten in April doing real damage and the follow-ups, Mascot and Goodwood, achieving progressively less as the Germans thickened the smoke screens and the flak; the escort carriers' part in that is described in the article on HMS Pursuer (D73). The trouble was the weapon. A Barracuda could carry a 1,600lb armour-piercing bomb, and a 1,600lb bomb dropped from the height a dive bomber survives at will wreck a battleship's upper works and not get through her deck armour. Implacable's abortive sortie of 18 October 1944 was one of the last naval attempts. Three and a half weeks later, on 12 November, Lancasters of 617 and 9 Squadrons put two 12,000lb Tallboys into her from twelve thousand feet and she capsized in Tromso fjord within about ten minutes. The Fleet Air Arm had spent two years and a good many aircrew on her, and the RAF finished it with two bombs.

She made up for it later that month with Operation Athletic, a sweep along the Norwegian coast in which her aircraft claimed six ships and a U-boat sunk for the loss of a single Barracuda, a properly productive start to her operational career for a carrier that had only just entered service.

Operation Athletic and the sweeps like it were a bigger part of the naval war than they look. Germany fought the whole war short of iron ore, and the ore came from Sweden, down the Norwegian coast by sea in small coasters running inside the leads, the sheltered channel between the mainland and the offshore islands. Submarines could not easily get in there, surface ships could not stay, and so from 1944 the job fell to carrier aircraft and to RAF strike wings: find the coasters, attack them in fjords ringed by mountains and flak, and get out. It was, by the accounts of the men who did it, some of the most frightening flying of the war, done at low level in narrow water where there was nowhere to go if the aircraft was hit. Six ships and a U-boat in a single sweep, for one Barracuda lost, is an exceptionally good day at that work.

Striking the Home Islands

HMS Implacable transferred to the British Pacific Fleet in 1945 and, on 14 and 15 June, struck the isolated Japanese base at Truk in the Caroline Islands as part of Operation Inmate, a deliberate piece of combat seasoning intended to give her and the fleet's newer ships some live experience before the altogether tougher business of striking the Japanese home islands. Her escort carrier HMS Ruler took over the routine work of servicing her standing combat air patrol of eight Seafires so that Implacable's own deck could stay focused on offensive sorties, and over the two days she flew 113 of them for the loss of a single Seafire, before withdrawing to Manus Island on 17 June to resupply.

Truk is worth a word too, because striking it in June 1945 sounds odd and was deliberate. It had been the main Japanese fleet base in the central Pacific, the equivalent of Scapa Flow, until American carrier strikes wrecked it in February 1944; after that the Allies simply went round it. That was the whole American island-hopping strategy: take what you need for airfields, bypass the rest, and let the garrisons sit there. By 1945 Truk held tens of thousands of Japanese troops with no shipping, no aircraft worth the name and no food coming in, growing vegetables to stay alive and entirely irrelevant to the war. Hitting it was a live-firing exercise for ships and air groups that had not been in action, which is exactly what Operation Inmate was for and why Implacable flew 113 sorties for the loss of one Seafire. The bypassed garrisons across the Pacific did not surrender until August, and a great many of the men in them starved.

She went on to strike targets in the Japanese Home Islands themselves as the war entered its final, most intense phase, by then part of Task Force 37, the British contribution to Admiral William Halsey's US Third Fleet. Her aircraft flew over 1,000 sorties during her Pacific operations altogether, a particularly demanding operational tempo that placed her at the very forefront of Allied naval air power in the last months of the war against Japan.

The last two months are a good deal more interesting than the phrase British contribution suggests. Task Force 37 sailed from Manus on 6 July, joined the American fast carriers on 16 July and struck Tokyo and its surroundings on the 17th and 18th, and thereafter operated as a component of Halsey's Third Fleet in the final assault on Japan. Two things about that were difficult. The first was logistics: the Royal Navy had no forward base within thousands of miles and had built an improvised supply organisation from scratch, and it could barely keep up with the American operational tempo. Two delays to strikes ordered by Halsey, for his own reasons, happened to give the British an extra day each to refuel, without which they could not have stayed on station; the Fleet Train that made even that possible is described in the article on HMS Berry Head (A191). The second was politics. When the remains of the Japanese fleet were finished off at Kure in late July, Halsey deliberately kept the British out of it, on the reasoning that the Americans should have the credit for destroying the navy that had attacked Pearl Harbor. It is hard to see what it cost him to share, and naval historians on both sides of the Atlantic have been unimpressed with him about it ever since.

Bringing the Prisoners Home

HMS Implacable's role following Japan's surrender shifted to remarkably humanitarian work: she transported over 2,000 British, American and Canadian prisoners of war, along with returning troops, home throughout the latter part of 1945, a welcome and deeply meaningful task after years of brutal captivity for the men she carried, and a fitting final wartime duty for a carrier that had spent her active service hunting battleships and striking the enemy's home territory.

The repatriation work was harder than it sounds and it marked the ships that did it. The men coming aboard had been prisoners of the Japanese for up to three and a half years, on the Burma railway, in the mines in Japan, in camps in Java and Formosa and Manchuria; something like a quarter of British and Commonwealth prisoners of the Japanese did not survive captivity at all, against a rate in German hands of a few per cent. Those who did came out weighing six or seven stone, riddled with beriberi, malaria, dysentery and tropical ulcers, and in many cases needing feeding up for weeks before they could safely travel at all. Carriers were the obvious ships for it: an empty hangar is a very large open space, and one that can be filled with bunks, kitchens and a sick bay. Implacable brought home more than two thousand of them. Her hangar had been designed to hold aeroplanes it turned out to be too short for; it turned out to be exactly the right size for this.

Her travels after the war took her right around the Pacific rim: she passed under Vancouver's Lions Gate Bridge on 11 October 1945, most likely as part of that same trooping and repatriation effort, and returned to the city again on 10 February 1947 while serving with the postwar Home Fleet, a rather more leisurely sort of voyage than the one that had taken her hunting Tirpitz three years earlier.

The End

HMS Implacable was decommissioned on 1 September 1954 and sold to Thos. W. Ward for breaking up on 27 October the following year, ultimately scrapped at Inverkeithing, closing out the career of a carrier whose combat service, though comparatively brief given her late entry into the war, had properly spanned the full breadth of the conflict's final year, from the fjords of Norway to the shores of Japan itself.

Ten years in commission for a ship that took five and a half to build is a poor return, and the reason goes back to those two feet. By the early 1950s carrier aviation meant jets, jets were larger and heavier than anything she had been designed around, and a hangar with fourteen feet of headroom could not take them; nor could her lifts, nor her deck. She could have been rebuilt, and the cost of doing it properly was close to the cost of a new ship, which is why the Navy put the money into the Audacious class instead. So a carrier that had hunted Tirpitz off Norway, bombed a bypassed fortress in the Carolines, flown against Tokyo alongside the United States Third Fleet and carried two thousand starved prisoners home went to the breakers at Inverkeithing in 1955, having never once been hit by anything. She is the clearest illustration in the fleet of a truth that applies to most warships: the decisions that determine how long a ship lasts are usually taken years before she floats, by people doing sums.