In the early 1930s, the French and Soviet navies put forward large-scale shipbuilding plans, prompting Germany to consider building more large ships. 1933, Hitler came to power. At the beginning, I was worried about the restrictions of the treaty, and I dared not openly build large warships that exceeded the standard, nor did I dare to openly challenge Britain's sea power. Hitler made it clear to Lei Deer, then commander of the German navy, that although he didn't want to build a fleet to challenge Britain's sea power, he wanted to fight against the ongoing French shipbuilding plan. At that time, the Soviet navy was still very weak and did not attract the attention of Germany; Although there are signs that it is implementing a huge shipbuilding plan.
The shipbuilding plan of the German Navy 1933 is limited to defending Germany's maritime traffic lines in the Baltic trade war. But by 1935, the general staff of the German navy had planned to expand the total tonnage of shipbuilding to 42 1000 tons, part of which was used to build heavy cruisers. In fact, as early as the late 1920s, Germany began to consider the design and construction of heavy cruisers, but due to the restrictions of the Treaty of Versailles, it failed to do so.
The Germans predicted that if the war broke out again, they would have to go to war with their potential rivals Britain and France, so they kept pace with the world's advanced level in ship quality. Judging from the several light cruisers owned by Germany at that time, it was far from being able to compete with similar ships of Britain and France. Therefore, in February of 1934, Germany decided to carry out the preliminary design of the heavy cruiser scheme. The design requirements must meet the following three main conditions: the firepower is comparable to that of the French navy's heavy cruiser Algiers, the speed is faster than that of the French navy's "Dunkirk" class combat cruiser, and the endurance can meet the requirements of Atlantic operations.
After deciding to design heavy cruisers, the German Navy initially considered two options in the selection of main guns. One is to use 150 mm 12 main gun, and the other is to equip eight 203.2 mm main guns. However, Admiral Lei Deer, the commander of the navy, soon preferred to use large-caliber main guns, and the proposal of using 190 mm main guns as a compromise was not passed. Because of the need to increase the hull size to equip the 203.2 mm main gun, the original design was greatly modified soon. Although the main indicators are still within the framework of the treaty heavy cruiser, they have exceeded the requirements of similar foreign ships.
There are many options for propulsion power plant. Because Germany has advantages in the development of diesel engine technology and high-pressure steam boiler, these two propulsion power schemes have been put on the table for discussion. /kloc-in the summer of 0/934, Germany finally decided to adopt 203.2 mm main gun and high pressure steam turbine. The original design displacement of 65,438+00,700 tons was allocated to 265,438+040 tons for armor protection and 65,438+0980 tons for mechanical power, and the thickness of the side armor was 85 mm. Because Germany was not a signatory to the Washington Naval Treaty, and the design of this class of ship could not meet all the requirements within the tonnage range stipulated in the treaty, the pace of Germans exceeding the treaty limit was still relatively large. After the completion of the first two ships, the straight and slightly curved bow and the traditional cruiser bow are still used, with moderate bulbous bow to reduce the resistance of high-speed waves. This class of ships has a large length and aspect ratio, which is helpful to reduce resistance and improve speed.
During the construction of this class of ships, due to the great development of welding technology, Germans used a large number of welding methods to build them. Compared with riveting, welding saves a lot of ship weight, which is beneficial to the use of high-strength steel and improves the protective strength of the whole ship.
When this class ship was in service, the German Navy had realized that the scharnhorst class battle cruiser and the original straight bow of this class ship had serious waves in bad sea conditions, which affected the navigation performance. So soon after serving, it began to be converted into an Atlantic bow, also known as a flying shear bow. Facts have proved that this bow is more suitable for the North Sea and Atlantic environment, which has also become the appearance symbol of large German warships.
The standard displacement of hippel and blucher is 14247 tons, the full displacement is 18208 tons, the total length is 205.9 meters, the waterline is 194.2 meters, the ship width is 2 1.3 meters, and the draft is 5.8 meters. The standard displacement of the improved "prinz eugen" and its two subsequent ships is14,475 tons, the full-load displacement is18,400 tons, the total length is 2 12.5 meters, the waterline is 199.5 meters, the ship width is 210.9 meters, and the draft is 0.9 meters. The crew is 1600. The design of Hippel-class heavy cruisers emphasizes the speed of warships, so the power requirements for propulsion devices are very high. The original plan was to use diesel engine, because diesel engine has low fuel consumption and large endurance. However, it is difficult for diesel engine power to reach a high speed of more than 30 knots, and it takes up too much space on board. Finally, according to the construction experience of the first two large warships, the Germans finally decided to adopt high-pressure and high-temperature steam turbines. Each ship is equipped with 3 steam turbines and 12 boilers. The boiler has high efficiency, the maximum power reaches 13363 1 horsepower, and the speed reaches 33.5 knots.
In order to maintain a high speed, the ship uses a steam turbine instead of a diesel engine, so the problem of short range has become the biggest weakness of this class of ship. Although they successfully attacked the allied transport lines, the shortage of fuel has always been a problem that plagued the German navy. During the war, hippel also changed some ballast tanks into fuel tanks. At the same time, the performance of the high-pressure steam turbine used by the German navy is also unstable, and the mechanism failures often occur. Nevertheless, their high speed still poses a great threat to the allies.