BB Tirpitz

Tirpitz and the ill-starred Bismarck were planned during the first years of the Nazi Regime as part of a class of heavy battleships which were to have a standard displacement of 45,000 tons; they followed the 33,000 ton battlecruisers Scharnhorst and Gneisenau as a further stage in the re-birth of the German Battle Fleet. It was intended to follow Tirpitz and Bismarck with six super-battleships of 60,000 tons, four large battlecruisers of 35,000 tons, six large fleet aircraft carriers, and all the battlecruisers, destroyers and other attendant craft needed to make a bid for supremacy on the high seas. Tirpitz was laid down at Wilhelmshaven in October, 1936, launched in April, 1939, and completed in November, 1940. She commissioned on 25 January, 1941, and spent the remainder of the year carrying out extensive trials, overcoming the inevitable teething troubles and working up into an efficient fighting unit. During this period she visited Kiel, Gdynia and Danzig, returning to Kiel at intervals for repairs and adjustments.

Meanwhile attention was being paid by the Germans to the future employment of their heavy naval units. In spite of the reverses suffered in the loss of, first, the pocket battleship Graf Spee and then the battleship Bismarck and also the blockading of the Scharnhorst and Gneisenau which had been at Brest since mid-March, 1941, there still remained formidable operational units for deployment. In August, 1941, Admiral Raeder (Commander-in- Chief of the German Navy) recommended the concentration of heavy ships in northern waters as promising strategic results. In December, 1941, Hitler demanded a concentration of battleships and pocket battleships in northern waters because latest intelligence had firmly convinced him that a British landing in northern Norway was imminent; he was deeply concerned at the possible catastrophic results of such a landing and said “The fate of the war will be decided in Norway”. The outcome was that in mid-January, 1942, Tirpitz sailed for Norway and approximately a month later Scharnhorst and Gneisenau made their historic dash through the English Channel in a successful effort to regain German ports.

Tirpitz’s first sortie was made from Trondheim in March, 1942, after a Russia-bound convoy had been shadowed by German reconnaissance aircraft. Torpedo carrying Albacores of the Fleet Air Arm made contact with the ship off the Lofoten Islands on 9 March and launched an unsuccessful attack following which Tirpitz retired at high speed. She returned to Trondheim and remained in that area until early July, 1942. On 7 July, British reconnaissance aircraft sighted Tirpitz off Tromsø and on 8 July the Russians claimed to have attacked her off North Cape with torpedoes fired from a submarine. The ship was next located at Bogen Fjord, near Narvik, where she remained until October, 1942, when machinery defects which had developed during the previous months made it desirable for her to return to Trondheim for repairs before the onset of the Arctic winter.

On 11 January, 1943, Hitler, furious at the failure of an attack on a convoy by Hipper and Lutzow, announced his intention of decommissioning the large ships. He told Raeder that the present critical situation demanded the application of all available fighting power, personnel and material, and that the large ships must not be permitted to be idle for months. On Hitler’s instructions Raeder produced a memorandum on the decommissioning of the large ships; he strenuously contested the decision but to no effect. Following this, Raeder resigned and was succeeded by Dönitz. Decommissioning of certain ships was put into effect, but following strong representations from Dönitz, Hitler agreed to keep Tirpitz and Scharnhorst in commission; Dönitz reasoned that these heavy units, together with Lutzow and six destroyers, would form a fairly powerful task force. On 2 February, 1943, Hitler issued an order for the cessation of work on the building of large ships.

The machinery repairs to Tirpitz appeared to have been completed (with spares brought from Germany) by the end of February, 1943, at which time she was reported as undergoing exercises in Trondheim Fjord. She left the Trondheim area in March, 1943, and joined the Scharnhorst and Lutzow in the Narvik area. The three ships left Narvik in company on 27 March and arrived in the Kaa Fjord, between Tromsø and North Cape, on 2 April. They stayed in this area until 7 September. On 9 September they carried out a raid on the Norwegian Islands of Spitzbergen with the object of destroying Allied bases and installations which were alleged to have been set up there. This raid indicated that the German battleship was likely to become more active and plans were therefore made to attack her with the X-Craft which had just come into operational service.

Three of the six X-Craft which were despatched to make this attack in the Kaa Fjord, to which Tirpitz had returned after the Spitzbergen raid, successfully negotiated the inner defences around her on 22 September and two of them laid their explosive charges on the sea-bed under or near the ship before being destroyed. At least two of these charges detonated as intended and the resultant damage immobilised Tirpitz for six months. At the end of this period, that is mid-March, 1944, she was reported as running trials in the Altenfjord and arrangements were made to lay on a bombing attack by Fleet Air Arm Barracudas from the Home Fleet Carriers. The first attack was made on 3 April by 40 Barracudas in two waves escorted by ship- borne fighters, just as Tirpitz was on the point of leaving her berth to run an extensive series of sea trials to test the repairs. The attack was a complete surprise, 14 hits were scored in spite of very low cloud, a smoke screen and the difficulty of attacking over mountains, and though the material efficiency of the ship was not seriously impaired, the heavy casualties meant that she would not be able to fight an action for some time.

Tirpitz was still in Kaa Fjord when she was again attacked by Fleet Air Arm aircraft on 17 July and 22, 24 and 29 August. Observer posts, which had been set up some distance from the anchorage, were able to give warning of these raids and a thick smoke screen, heavy anti-aircraft fire and low cloud prevented the attacks being pressed well home. Two hits were scored on 24 August but again no vital damage to the ship resulted.

The urgent necessity of releasing for the Far East the capital ships held at Scapa to counter the menace of Tirpitz made it imperative to render the ship inoperative at an early date. On 15 September, 1944, she was attacked at her anchorage in the Kaa Fjord with the new 12,000 lb. M.C. bombs (Tallboys) which had been developed primarily for land demolition purposes. 21 Bomber Command Lancasters, operating from a Russian base, found the ship almost completely obscured by smoke. Only one hit (at the fore end) was registered owing to the extreme difficulty of carrying out a high level bombing attack in the poor visibility conditions prevailing, but severe damage was caused and Tirpitz was henceforth incapable of being a threat to shipping. However, this fact did not become known to the Allies until the termination of the war, and the attacks continued.

Following this latest damage the Germans held a Conference at which they decided that as it was no longer possible to make Tirpitz ready for sea and action again, the ship’s remaining fighting efficiency should be utilised as a reinforcement of the defences in the Polar Area. On 15 October Tirpitz was moved to a berth near Tromsø and arrangements were made to protect her with anti-aircraft and smoke defences and land-based aircraft. This berth was supposed to conform to special requirements laid down at the Conference, one of which limited the maximum depth of water in the anchorage to a figure which would have prevented the ship from capsizing; the depth at the position in which Tirpitz was finally moored exceeding this limit and a hasty attempt was made to build up the sea-bed by depositing dredged material around and under the ship, which became known as “The Floating Battery”.

On 29 October, 1944, Lancasters again attacked with 12,000 lb. bombs. Heavy cloud obscured the Tromsø anchorage and militated against accurate high level bombing but a near miss off the port quarter produced flooding aft.

Finally, on 12 November, 1944, the somewhat inactive operational career of Tirpitz was brought to a close when Lancaster aircraft bombed her with 12,000 lb. Tallboys for the third time, scoring hits which – aided by one near miss – caused the world’s only “unsinkable” battleship to capsize in about ten minutes with the loss of some 1,000 lives.

Ship Description

There was nothing sensational about the design of Tirpitz; she was merely a very large battleship, designed on conventional lines, propelled by three screws driven by steam turbines and mounting eight 38 cm. (approx. 15-in.) guns in twin turrets, arranged in the conventional way, two forward and two aft. This German mastodon was designed to a standard displacement of 42,600 tons, although the displacement reported for Treaty conditions was 35,000, the same as that of the King George V and Washington classes of battleship, which were genuinely designed to this size. In the deep condition she displaced 50,000 tons and had a draught of nearly 34 ft. Other things being equal this greater displacement would have been accompanied by greater ability to withstand damage. Although she measured 822 ft. overall, her most impressive dimension was her beam of 118 ft. which would have prevented her from passing through the Panama Canal. It was always thought that this implied a very deep “bulge” for protection against underwater attack, but it is now known that there was nothing remarkable about her underwater protection which was, in fact, inferior to that fitted in both British and American contemporary Capital Ships. The very large beam was adopted to provide an abnormally high initial stability. Such measures, however, may often reduce the resistance of the ship to the more severe states of damage. It is doubtful whether Tirpitz was at all better than her allied counterparts in this respect.

Information gained from a survey of the wreck and numerous drawings brought from Germany confirm that Tirpitz’s reputed fine watertight subdivision, and consequent “invincibility”, were a complete myth; her subdivision was very similar to that of our own Capital Ships, and indeed those of all major sea Powers. Her watertight integrity was in several ways subordinated to requirements of convenience; for example, every transverse watertight bulkhead in the ship was pierced by watertight doors on the lower and middle platform decks, a menace which has been eliminated from H.M. ships for many years, and the engine rooms seemed to contain far more space than was needed.

Some of the available weight was used to secure a very high speed. Tirpitz was designed to develop 150,000 shaft horse-power which enabled her to make over 30 knots in the average action condition, and she was capable of developing 165,000 shaft horse-power for sudden bursts of over 31 knots. Her range based on an oil fuel capacity of 5,000 tons was over 10,000 sea miles. More fuel could be carried in an emergency.

More of the extra displacement in Tirpitz was accounted for by the fact that her 38 cm. guns were mounted in twin turrets rather than the weight saving triple and quadruple arrangements used in modern American and British Capital ships. Also the Germans fitted separate low angle and high angle secondary batteries rather than the dual purpose mountings used in Allied ships. She thus had twelve 15 cm. (5.9-in.) low angle guns in twin turrets, three on either side of the amidships superstructure, and sixteen high angle 10.5 cm. (4.1-in.) guns in twin mountings – four on each side. A further battery of sixteen 3.7 cm. (1.46-in.) mountings for close range anti- aircraft work was also provided.

This powerful armament was controlled by range-finders and director sights on the forward and after conning towers, and on the fore top. There were smaller range-finders for the secondary armament, one on each side of the bridge. The 10.5 cm. H.A. armament was controlled by four special gyro stabilized directors, one to port and one to starboard of the bridge, and two on the centre line abaft the main mast.

Tirpitz’s general layout is illustrated by the small-scale drawings below. It will be seen from the drawing that the machinery spaces, consisting of six boiler rooms, three engine rooms and miscellaneous compartments housing auxiliary machinery, the magazines and shell rooms, and other vital compartments such as fire control rooms, were well protected by a long armoured citadel. The sides were of 320 mm. (12.6-in.) thick cemented armour plates from 8 ft. below the waterline up to the battery deck and thinner plating of 145 mm. (5.7-in.) thickness to the upper deck. In addition, the third deck down was armoured with 80 mm. (3.15-in.) non-cemented plating over the machinery spaces and 100 mm. (3.94-in.) over the magazines between the torpedo bulkheads, while the sloping deck armour between the centre portion and the base of the side armour was 110 mm. (4.33-in.) in way of machinery spaces and 120 mm. (4.72)-in.) in way of magazines. There were extensions of the citadel by thinner armour, the lower belt being 60 mm. (2.36-in.) plating forward and 80 mm. (3.15-in.) aft and the upper belt being 35 mm. (1.38-in.) forward and aft. While there was no deck armour before the forward magazines, deck protection aft over the steering gear compartments was 110 mm. (4.33-in.) in thickness. This armoured citadel, re-inforced by a strength deck (the upper deck) which was 50 mm. (1.97-in.) thick generally, afforded efficient protection against splinters and all but the largest bombs dropped from a considerable height. Barbettes, and turret sides and roofs, and greater ability to withstand damage. Although she measured 822 ft. overall, her most impressive dimension was her beam of 118 ft. which would have prevented her from passing through the Panama Canal. It was always thought that this implied a very deep “bulge” for protection against underwater attack, but it is now known that there was nothing remarkable about her underwater protection which was, in fact, inferior to that fitted in both British and American contemporary Capital Ships. The very large beam was adopted to provide an abnormally high initial stability. Such measures, however, may often reduce the resistance of the ship to the more severe states of damage. It is doubtful whether Tirpitz was at all better than her allied counterparts in this respect.

Information gained from a survey of the wreck and numerous drawings brought from Germany confirm that Tirpitz’s reputed fine watertight subdivision, and consequent “invincibility”, were a complete myth; her subdivision was very similar to that of our own Capital Ships, and indeed those of all major sea Powers. Her watertight integrity was in several ways subordinated to requirements of convenience; for example, every transverse watertight bulkhead in the ship was pierced by watertight doors on the lower and middle platform decks, a menace which has been eliminated from H.M. ships for many years, and the engine rooms seemed to contain far more space than was needed.

Some of the available weight was used to secure a very high speed. Tirpitz was designed to develop 150,000 shaft horse-power which enabled her to make over 30 knots in the average action condition, and she was capable of developing 165,000 shaft horse-power for sudden bursts of over 31 knots. Her range based on an oil fuel capacity of 5,000 tons was over 10,000 sea miles. More fuel could be carried in an emergency.

More of the extra displacement in Tirpitz was accounted for by the fact that her 38 cm. guns were mounted in twin turrets rather than the weight saving triple and quadruple arrangements used in modern American and British Capital ships. Also the Germans fitted separate low angle and high angle secondary batteries rather than the dual purpose mountings used in Allied ships. She thus had twelve 15 cm. (5.9-in.) low angle guns in twin turrets, three on either side of the amidships superstructure, and sixteen high angle 10.5 cm. (4.1-in.) guns in twin mountings – four on each side. A further battery of sixteen 3.7 cm. (1.46-in.) mountings for close range anti- aircraft work was also provided.

This powerful armament was controlled by range-finders and director sights on the forward and after conning towers, and on the fore top. There were smaller range-finders for the secondary armament, one on each side of the bridge. The 10.5 cm. H.A. armament was controlled by four special gyro stabilized directors, one to port and one to starboard of the bridge, and two on the centre line abaft the main mast.

Tirpitz’s general layout is illustrated by the small-scale drawing (Figure 2) which has been prepared for this report from larger scale drawings found in the Naval Arsenal at Kiel. It will be seen from the drawing that the machinery spaces, consisting of six boiler rooms, three engine rooms and miscellaneous compartments housing auxiliary machinery, the magazines and shell rooms, and other vital compartments such as fire control rooms, were well protected by a long armoured citadel. The sides were of 320 mm. (12.6-in.) thick cemented armour plates from 8 ft. below the waterline up to the battery deck and thinner plating of 145 mm. (5.7-in.) thickness to the upper deck. In addition, the third deck down was armoured with 80 mm. (3.15-in.) non-cemented plating over the machinery spaces and 100 mm. (3.94-in.) over the magazines between the torpedo bulkheads, while the sloping deck armour between the centre portion and the base of the side armour was 110 mm. (4.33-in.) in way of machinery spaces and 120 mm. (4.72)-in.) in way of magazines. There were extensions of the citadel by thinner armour, the lower belt being 60 mm. (2.36-in.) plating forward and 80 mm. (3.15-in.) aft and the upper belt being 35 mm. (1.38-in.) forward and aft. While there was no deck armour before the forward magazines, deck protection aft over the steering gear compartments was 110 mm. (4.33-in.) in thickness. This armoured citadel, re-inforced by a strength deck (the upper deck) which was 50 mm. (1.97-in.) thick generally, afforded efficient protection against splinters and all but the largest bombs dropped from a considerable height. Barbettes, and turret sides and roofs, and conning towers were protected by armour on the same generous lines.

Four sea-planes which were carried for spotting and reconnaissance were accommodated in special hangars abreast the funnel and under the main mast. They were launched by a fixed athwartships catapult between the funnel and the main mast.

It will be seen from this description that the Tirpitz and her sister ship, the Bismarck, were formidable – if conventional – fighting units which required our best ships and weapons to counter them, and which were capable of defeating attacks by heavy shell and all but the heaviest bombs. While Tirpitz remained in the Norwegian Fjords, powerful British units had to be kept in Home waters to protect our shipping.

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