Operation Tungsten was a Second World War air raid by the Fleet Air Arm of the Royal Navy against the German battleship Tirpitz. The operation sought to damage or destroy Tirpitz at her base in Kaafjord in the far north of Norway before she could become fully operational again following a period of repairs.
The British decision to strike Kaafjord was motivated by fears that the battleship, upon re-entering service, would attack strategically important convoys carrying supplies to the Soviet Union. Removing the threat posed by Tirpitz would also allow the Allies to redeploy the capital ships which had to be held in the North Sea to counter her. After four months of training and preparations, the British Home Fleet sailed on 30 March 1944 and aircraft launched from five aircraft carriers struck Kaafjord on 3 April. The raid achieved surprise, and the British aircraft met little opposition. Fifteen bombs hit the battleship, and strafing by fighter aircraft inflicted heavy casualties on her gun crews. Four British aircraft and nine airmen were lost during the operation.
The damage inflicted during the attack was not sufficient to sink or disable Tirpitz but she suffered considerable damage to her superstructure and unarmored areas, with 122 members of her crew killed and 316 wounded. The German Kriegsmarine decided to repair the battleship, and works were completed by mid-July. The British conducted further carrier raids against Tirpitz between April and August 1944 to prolong the period she was out of service but all failed. Tirpitz was eventually disabled and then sunk by Royal Air Force heavy bombers in late 1944.
Background
The threat posed by Tirpitz had an important influence on British naval strategy. She was commissioned in February 1941 and completed her crew training late that year. At about the same time the German high command decided to station the battleship in Norway; this deployment was intended to deter a feared Allied invasion of Norway and threaten the Arctic convoys which regularly sailed through the Arctic Sea to the Soviet Union. The convoys carried large quantities of war material from ports in Britain and Iceland, and were frequently attacked by the German air and naval units stationed in Norway. Tirpitz arrived in Norway in January 1942 and operated from anchorages in fjords. While she was operational the Allies had to keep a powerful force of warships with the British Home Fleet to guard against the possibility of a sortie against the Arctic convoys and capital ships accompanied most convoys part of the way to the Soviet Union.
The British attacked Tirpitz several times during 1942 and 1943. When the battleship sortied to intercept Convoy PQ 12 on 6 March 1942 HMS Victorious, that formed part of the convoy's escort, attempted to attack her using torpedo bombers. These aircraft launched twenty torpedoes at the battleship but all missed. On several occasions during 1942 and 1943 bombers from the Royal Air Force and Soviet Air Forces attempted to strike Tirpitz in her anchorages but without success. On 23 September 1943 two British X-class midget submarines penetrated the defences around the battleship at her main anchorage at Kaafjord in northern Norway during Operation Source and placed explosive charges in the water beneath her. This attack caused extensive damage to Tirpitz, putting her out of service for six months.
Repairs to Tirpitz were carried out using improvised facilities at Kaafjord as it was considered too risky to attempt to move the warship to Germany, equipment and work crews were shipped to the fjord from German ports. On the night of 10/11 February 1944, 15 Soviet aircraft attacked the battleship but did not cause any damage. By 17 March, the repairs to Tirpitz's armament, machinery and hull were complete, but several minor repair tasks were outstanding. During the period the ship was under repair, Scharnhorst, the only remaining operational German battleship, was sunk on 26 December during the Battle of the North Cape. Following this engagement the Royal Navy stopped deploying battleships to cover convoys travelling to and from the Soviet Union. By this stage of the war the Allies also had large numbers of anti-submarine and anti-aircraft escort ships available, and were able to assign strong forces to protect the Arctic convoys. German submarines operating in the Norwegian Sea were rarely able to evade the convoy escorts, and few merchant vessels suffered damage from German attack.
The British Government and Royal Navy were concerned about the threat Tirpitz posed once she re-entered service. Allied intelligence tracked the progress of work on the battleship using decrypted German radio signals, photo reconnaissance flights and witness reports from agents in Norway. It was feared the battleship could sortie and attack convoys in the Norwegian Sea or Atlantic Ocean after the repairs were completed. The need to guard against this possibility would also occupy warships needed to support the planned Operation Overlord the invasion of France. It was decided in late 1943 to make further attempts to sink the battleship. Despite Allied concerns, Tirpitz posed only a limited danger to Allied shipping. From late 1943 the battleship was unable to put to sea for crew training due to the threat of Allied attack and fuel shortages. These shortages also meant the Germans were unable to move the battleship between anchorages to make her more difficult to locate and attack.
Preparations
The options for attacking Tirpitz at Kaafjord were limited. Another submarine-borne raid was considered impractical as intelligence gathered from intercepted radio transmissions and field agents indicated that the battleship's underwater defences had been improved and more aerial reconnaissance patrols of the region were being flown. The commander of the Royal Air Force's Bomber Command, Air Chief Marshal Sir Arthur Harris, also refused to attempt a heavy bomber raid on Tirpitz on the grounds that the Kaafjord area was beyond the effective range of these aircraft and the battleship's guns would cause heavy casualties. After these two options were ruled out, the task was assigned to the Home Fleet's aircraft carriers. At this time the large fleet carriers HMS Furious and Victorious and four smaller escort carriers were ready.
Planning for the raid on Kaafjord began in December 1943. Vice Admiral Bruce Fraser, the commander of the Home Fleet, was not optimistic about the prospects for success, and had to be persuaded to undertake the operation by First Sea Lord Sir Andrew Cunningham. Fraser gave his second in command, Vice Admiral Sir Henry Moore, responsibility for planning and leading the raid. The operation was initially designated "Operational Thrustful", but was later renamed "Operation Tungsten". The attack was originally scheduled for mid-March 1944, shortly before the time Allied intelligence believed Tirpitz would become operational. However, it was delayed by two weeks while Victorious was fitted with new radars. The British considered cancelling Operation Tungsten in February as Victorious was also needed in the Indian Ocean to counter a build-up of Japanese warships at Singapore. To enable the attack to proceed, the United States Navy agreed to temporarily transfer USS Saratoga to the Eastern Fleet so that Victorious could be retained in the North Sea.
The plans for the raid were centred on two dive-bombing attacks by Fleet Air Arm Fairey Barracuda aircraft. Led by Strike Leader Roy Sydney Baker-Falkner, each of the attacks was to involve 21 Barracudas escorted by 40 fighters; Vought F4U Corsairs flying from Victorious would provide protection against German aircraft while Wildcats and Hellcats operating from Furious and the escort carriers HMS Emperor, Pursuer and Searcher were to strafe anti-aircraft guns near Tirpitz and on the battleship. Aircraft flying from Furious and the escort carrier HMS Fencer would protect the fleet against attack by German aircraft or submarines. Carrier aircraft had lacked a bomb capable of penetrating a battleship's thick deck armour, it was hoped that the new 1,600-pound (730 kg) armour-piercing bomb would be able to pierce at least the first layer of Tirpitz's armour if they were dropped from an altitude of 3,500 feet (1,100 m) or higher. The damage caused by such hits was expected to put the battleship out of service. Nine of the Barracudas were to be armed with 1,600-pounders and a further 22 would each carry three 500 lb (230 kg) semi-armour-piercing bombs that were capable of penetrating the lightly protected upper decks of the ship if dropped from above 2,000 feet (610 m). The remaining ten aircraft would be armed with 500 lb (230 kg) and 600 lb (270 kg) general-purpose bombs and with anti-submarine bombs intended to inflict casualties among the battleship's crew and cause underwater damage if they exploded in the water near her hull. The aircraft carrying high-explosive bombs were to attack first as it was hoped that these weapons would knock out at least some of the battleship's anti-aircraft guns.
The Fleet Air Arm units selected for Operation Tungsten conducted intensive training from February 1944 under Roy Sydney Baker-Falkner with his very experienced 827 Naval Air Squadron and 830 Naval Air Squadron. A high proportion of the airmen of the 2nd Wing 829 NAS and 831 NAS were inexperienced and the captain of Victorious estimated that 85 per cent of the aircrew embarked on his ship had not operated at sea. The training programme was centred on Loch Eriboll in northern Scotland which, like Kaafjord, was surrounded by steep hills. Flying from RNAS Hatston in the Orkney Islands, aircrew practiced manoeuvring around this terrain to familiarise themselves with the tactics needed to avoid German anti-aircraft guns and attack Tirpitz. The Royal Navy drew on intelligence on the defences of Kaafjord to make the exercise range as similar to the conditions around Tirpitz as was possible, and the aircrew were extensively briefed on the locations of German positions. An area the size of the battleship was also marked out on an island in the centre of the loch and repeatedly bombed.
While these preparations were under way, the Allies continued to monitor Tirpitz. In late February the escort carrier HMS Chaser transported photo analysts and the ground crews for a Royal Air Force photo reconnaissance detachment to Vaenga airfield in northern Russia. These personnel were joined by three Supermarine Spitfires fitted for photo reconnaissance work and a Consolidated PBY Catalina in March. The Spitfires flew regular sorties over Kaafjord and took detailed photographs of Tirpitz and the nearby anti-aircraft batteries on 12 and 13 March; after being developed the Catalina flew these images to Britain. Although the German forces in northern Norway detected the Spitfire flights, the Kaafjord area's defences were not increased or placed on alert. On 16 March eight British, Dutch and Norwegian submarines were directed to take up positions off the Norwegian coast after decrypted German radio messages indicated that Tirpitz may have been preparing to depart Kaafjord for Germany to complete her repairs. A further eight British and Dutch submarines were dispatched on 18 March, but two days later it was concluded that Tirpitz was not about to put to sea and the submarines were diverted to other tasks or ordered back to port. On 21 March, British intelligence warned the Admiralty that due to recent Soviet advances on the Eastern Front, the Germans were placing a strong emphasis on disrupting the flow of supplies to the Soviet Union and could dispatch Tirpitz to attack any convoys not escorted by capital ships. Fraser was directed to provide battleship protection for the next Arctic convoy.
The final decision to undertake Operation Tungsten was made in mid-March on the basis of a decrypted radio message that indicated that Tirpitz was almost ready for combat and would conduct high-speed trials on 1 April. As a result of the delays to the operation, the sailing of the attack force coincided with the departure of Convoy JW 58 for the Soviet Union. It was hoped that if German forces spotted the British fleet it would be assumed that the warships were supporting the convoy. As part of the final preparations for the attack, a full-scale rehearsal was conducted using the training range at Loch Eriboll on 28 March. From 1 April, the Admiralty received hourly weather reports from a group of Norwegian Secret Intelligence Service agents in Alta, near Kåfjord.
Opposing forces
The Royal Navy assembled a powerful force for Operation Tungsten. The main striking force was made up of two wings of Barracudas. 8 Wing comprising 827 Naval Air Squadron and 830 Naval Air Squadron and 52 Wing with 829 and 831 Naval Air Squadrons. While 8 Wing was normally based on board Furious and 52 Wing on Victorious, Moore chose to station a squadron from each of the wings on each carrier so they could launch simultaneously and go into battle as formed units. The 163 Fleet Air Arm airmen in the attacking units included 28 New Zealanders, three Canadians, two Australians, and one South African; the remainder were British.