In the Asian battlefield, the Japanese troops were unstoppable, while in Europe the Germans fell into resistance with Britain, France and the United States.//**//
When the war broke out, there were about 3,000 ocean-going merchant ships flying the British flag around the world, and another 1,000 offshore trading cargo ships regularly plied the British coastal waters. The total tonnage of these transport fleets reached 17.5 million tons. In domestic waters and the North Atlantic, these merchant ships usually
Formed into a fleet, escorted by 4-6 armed ships equipped with depth charges. After receiving information that German warships may appear on the route, the British Home Fleet will also dispatch heavy warships to undertake long-distance escort missions.
The lifeline of maritime transportation is crucial. Without maritime transportation, Britain cannot even solve the problem of feeding its people, let alone manufacture weapons. It can be said that once there is no import of goods, Britain will not even be qualified to participate in the war.
However, the German navy was not ready to take advantage of Britain's weakness. Germany's original naval involvement in the war was in the mid-1940s. Unable to engage in a face-to-face battle with the British fleet, Germany had no choice but to attack merchant ships.
The "Deutsche" class heavy cruiser, commonly known as "pocket battleship", is Germany's first main battleship class, with a gun caliber up to 28 cm. This class of ship is only designed to attack commercial ships and uses diesel power.
The endurance is excellent. Before the outbreak of the war, the German Navy's "Admiral Scheer" and "Graf Schell" were sent to the Atlantic Ocean, preparing to go into battle immediately after the declaration of war. The two ships frequently attacked the Central and South Atlantic.
Unescorted merchant ships sailed, and all achieved partial success. The "Admiral Scheer" sank 16 ships with a total tonnage of 100,000 tons in five months of attacks.
However, pocket battleships all operate alone and are easily attacked by concentrated firepower from the powerful British Royal Navy. In December 1939, while operating in the South Atlantic, the "Graf Spee" was discovered by a British Royal Navy cruiser squadron and was eventually captured.
It was forced to sink itself at the mouth of the Platte River. The new heavy battleships of the German Navy are not very suitable for breaking up engagements. The "Hipper" class heavy cruisers use high-pressure steam thrust, which consumes a lot of fuel and thus limits the range. However, "
The "Admiral Hipper" once successfully intercepted a convoy off the coast of West Africa and sank 7 ships with a total tonnage of 27,210 tons.
The battlecruisers "Scharnhorst" and "Gneisenau" sank the Royal Navy aircraft carrier "Glorious" in the Norwegian Campaign. However, because their firepower was too light, they could not be regarded as true battleships.
Their role in the subsequent campaign was arguably inconsequential, as the Royal Navy sent older "R" and "Queen Elizabeth" class battleships to escort the two ships in an attack on the British convoy in the North Atlantic.
suffered a disastrous defeat. [Very literary].
The German Navy also used a large number of armed merchant cruisers, and achieved good results. These ships were designed to be very similar to ordinary merchant ships, but they concealed heavy weapons under their camouflage. Judging from the number of ships they sunk·
The results of the armed merchant cruisers were not great, and they never posed a threat to the Allies' sea control. However, the attacks by the armed merchant cruisers caused great panic to the merchant ships, forcing the Royal Navy to send a large number of troops to hunt them down.
Although the German propaganda machine continued to publicize the navy's surface attack deeds as typical material, the German navy was unable to concentrate its large warships to carry out a decisive blow to the Allies. Scattered actions to break diplomatic relations could only harass the Allies at best.
In sharp contrast to the surface fleet, the German Navy's U-boat force posed an extremely serious threat to the Allies.
Karl, Commander of the German Navy's Submarine Forces.
Admiral Dönitz valued submarines very much. He believed that to complete the naval blockade of Britain, a fleet of about 250 or 300 submarines was needed. According to Hitler's pre-war "Plan Z", the ambitious Nazi
In the naval construction plan, Germany plans to build such a fleet and form combat effectiveness by 1943. However, while building a powerful submarine fleet, Germany also plans to form two giant battleship squadrons and build the largest battleship in the world. Due to the preference of the German High Command
The construction plans of battleships and submarines were put on the back burner and delayed. In Dönitz's view, this was unrealistic.
He believed that only by relying on submarines could we hope to complete the blockade of Britain.
Dönitz's understanding of submarines originated from World War I.
The German Imperial Navy was the first force to use submarines in large numbers to attack enemy merchant ships. Although the submarines at that time were relatively crude and simple in construction, they achieved considerable success. The German H-type submarines had a huge impact on British trade in the Mediterranean.
The unrestricted submarine warfare of 1917-1918 almost brought Britain to its knees. This was also a major reason why Germany was prohibited from developing a submarine force in the Treaty of Versailles signed after the war.
Despite treaty restrictions, Germany secretly established submarine design offices in the Netherlands in 1922 and Berlin in 1927!
A few months before Hitler came to power in 1932, the Weimar government passed a naval construction plan including 16 U-boats. After the rise of the Nazis, the naval construction plan was accelerated. In 1935, Hermann.
Goering announced to the world that Germany would re-arm and accept the Treaty of Versailles. Hitler also worked hard to get Britain and Germany to sign the "Naval Agreement", which allowed Germany's naval power to reach up to 45% of the Royal Navy's strength. But it was puzzling.
Unfortunately, despite Britain's painful experience of being attacked by submarines in World War I, the agreement allowed the German submarine force to be equal to the British in terms of total tonnage.
It was in this year that #Zenitz was ordered to command Germany's first post-war small submarine fleet and began to train a new submarine fleet to complete the mission that the German Navy almost completed during World War I. After taking charge of the German submarine fleet
After forming the army, Dönitz determined the types of submarines most suitable for offshore and ocean warfare and the number of submarines to build.
#One of the needs identified by Zanitz was to build an offshore submarine, so the Type Pi submarine was quickly put into production. Actual combat showed that the Type Pi submarine was flexible and highly maneuverable, and could submerge rapidly within 25 seconds. Because
The boat was small and easy to maneuver, and it quickly earned the nickname "canoe."
In the Battle of the Atlantic, Germany mainly used Type Yin submarines. Like the Type Pi submarine, the Type Yin submarine was originally intended to be used to fight Finland and was built in 1930. This type of submarine was produced in large quantities, and by the time of the war
By the end, there were more than 800. Although Germany intended to use this submarine for ocean warfare, in order to maximize the production of this type of submarine within treaty restrictions, its size was relatively limited, which in turn enhanced its flexibility and rapidity.
The ability to submerge.
Like most submarines at the time, the Type Yin submarine's power plant used a diesel engine when sailing on the surface, and a battery-driven electric engine when underwater. When driven by diesel-electric power, the Type Yin submarine's speed could reach speeds up to 100% compared with slow speed.
The merchant fleet is more than enough to encircle; but when traveling underwater, its sailing speed can only reach 5 knots at the fastest, and it can only maintain this speed for a few hours. The tqpe Y-type submarine carries 11 to 14 torpedoes. In the early days
The submarines produced were also equipped with a deck gun. Later in the war, the deck gun was often replaced by a more prominent heavy anti-aircraft gun.
The larger type submarines are designed according to the requirements of ocean warfare. The early production type submarines have a longer sailing distance and can fight in the southern hemisphere, often cruising in the South Atlantic. The later production models have a further increased sailing distance and can sail in
It can travel to the Indian Ocean and even the Pacific Ocean without refueling. The living conditions of its crew have also been improved, making it suitable for long-term activities. The number of torpedoes it carries is 22, which is about 1.5 times that of the Y-type submarine.
.Despite this, the crew still prefers the smaller Type Yin submarine because the small submarine has a fast diving speed and strong underwater maneuverability. The larger Type Yin submarine takes 40 seconds to make an emergency dive, which is extremely difficult.
Vulnerable to air attack.
Until the summer of 1939, Hitler was still preaching that the German navy was not in danger of being involved in the war. At that time, #Zenitz had only 46 combat submarines, more than half of which were "landlubbers" that could only sail in coastal waters, that is, type Pi.
Type submarines, these submarines are mainly used for training.
In the first eight months after the outbreak of the war, German submarines conducted very few attacks against Britain's main supply lines. Almost all operations were against individual ships that broke away from the convoy. Moreover, during the Norwegian Campaign, in order to ensure the safety of ships in the North Sea,
During the war, Germany even withdrew all submarines operating in the Atlantic Ocean.
This situation later changed. During the interwar period, Dönitz developed the theory of boat attack tactics. After taking charge of Hitler's submarine force, he experimented with the concept of "wolf pack tactics":
This is a tactical concept of coordinated attacks with submarine groups in the open ocean. Another submarine warfare technology advocated by Dönitz was what he learned in World War I, that is, launching an attack from the water at night can obtain
Best results.
In 1939, he published a book detailing these tactics, including how small-profile submarines were less likely to be detected when sailing at night, and how submarines in the 1930s could reach speeds higher than the average merchant ship when sailing on the surface.
Out a lot of speed etc. Sadly no one in the UK seems to have noticed this book!
The initial declared war zone extended westward to about 800 kilometers west of Iceland.
In the first few months of the war, the results of German submarines were considerable. The main targets of attack were merchant ships sailing to Britain alone. German submarine commanders were more worried about British destroyers, because these ships were equipped with asdic underwater sonar systems, which could
Detect the distance and bearing of a submarine traveling underwater.
However, the UK does not have enough anti-submarine destroyers, and there will never be enough, because the UK is mass-producing small frigates and light cruisers that can serve as anti-submarine missions to replace anti-submarine destroyers, and it will take several years for this production plan to reach high volumes.