Next to the Bismarck the largest German World War II ship was the battleship Tirpitz . The order was placed with the naval shipyard at Wilhelmshaven in June 1936 and the keel was laid on 2nd November of the same year. The subsequent construction and completion of the superstructure and armament was delayed by numerous British air raids on the Wilhelmshaven shipyards; so that the “Tirpitz†did not go into service until 25th February 1941. After two more British bombing raids the "Tirpitz" was moved to Gotenhafen where her first exercises started in the Baltic Sea. The main differences between the Tirpitz and Bismarck were the steam turbines from different manufacturers and details of the superstructures and equipment. The hull was largely of the same design as that of the Bismarck and was constructed in accordance with the long rib method developed by the German Navy with 22 watertight compartments. For protection against mines most of the ships bottom had a water and oil-tight double bottom. The longitudinal members and transverse bulkheads made of high tensile steel St 52 provided a light-weight construction while meeting all strength requirements. The whole hull inclusive of all armoured components and the armouring of the upper deck was almost completely electric welded. Only the torpedo bulkheads running parallel to the side walls of the hull and made of Krupp soft Wotan armoured material were made with riveted plate. The top deck was made of hard Wotan also the armoured deck below it and the forward and after sections. The control tower, sides of hull (belt plates), main turret, gun turrets and gun shields of the medium artillery were protected by Krupp cemented armour plating . The armoured belts on the sides of the hull were at a height of about 5 m over 170 m long and 320 mm thick. In addition to a multiplicity of optical range-finders for sea and air target acquisition, three radar sets were included. A total of 840-960 rounds of heavy artillery consisted of 800 kg heavy projectiles and a two-part propellant charge giving a maximum range of 36.2 km. With a firing speed of 5 rounds in 2 minutes and at a range of over 21 km they were capable of penetrating 350 mm armour. Each turret weighed 1,052 tonnes. Traversing and aiming was electric or (normally) hydraulic. After the attack on the Soviet Union, from July 1941 the Tirpitz operated as part of the Baltic Fleet. On completion of the subsequent exercises in the Baltic, on 10th January 1942 Captain Topp reported that she was fully operational. As an Allied invasion of Norway was feared, on 16th January 1942, the battleship escorted by several destroyers reached Trondheim. The German naval command intended to use her in a larger battle formation against the convoys in and out of Murmansk. The battleship would in future serve to keep the enemy naval forces in the North Atlantic. In the following months the ship travelled between various fiords along the Norwegian coast. She was overhauled in Trondheim from October to December 1942, then moved to Narvik and in March 1943 to the Altafjord. Among others together with the Scharnhorst , on 8th September 1943 the Tirpitz shelled enemy positions on Spitzbergen. As a consequence the British Admiralty decided to combat the Tirpitz . On 23rd September 1943 British mini-submarines had succeeded in diving through the net defences and two mines were detonated under Tirpitz as she lay at anchor in the Kaafjord. A return to Germany was too risky, so that the repair work in Norway lasted until March 1944. The subsequent trial runs were thwarted by another air raid on 4th April 1944 by Royal Navy aircraft carriers; extensive damage had been caused. The next repair work lasted until 1st July 1944, when she was reinforced with air defences, radar and smoke generators. On 15th September 1944 a Tall Boy bomb from an RAF Bomber Command Lancaster hit the Tirpitz which was shrouded in artificial mist, tore a hole in the bow and destroyed a 36 m length of the hull structure. The Tirpitz was seriously damaged and moved to Troms in the middle of October 1944. Here the damage was due to be replaced within nine months. However, the anchorage was within range of the specially modified Avro-Lancaster aircraft that took off from Great Britain, so that on 29th October 1944 the RAF launched a first attack on Troms. The Tirpitz received a near hit and was badly damaged again. A second British raid sealed the feat of the battleship on 12th November 1944. After two direct hits by Tall Boy bombs the Tirpitz capsized. The lives of 1,204 crew members were lost and 809 were saved.