“Germany,” admiral von Tirpitz declared, addressing the Reichstag in 1901, “doesn’t need submarines”. That is why the German imperial fleet received its first submarine only in 1906 year, later many countries of the world, including Portugal and Turkey.
By design, submarines were divided into one-hull, one-and-a-half, and two-hull. The single-body submarine had one strong hull with a superstructure and a light fore end. This type of submarine usually had a small displacement (100-250 tons), and could pass in a surface position at a speed of 8 nodes from 500 to 1500 miles. These small ships were used to protect sea bases and patrol the coast.
The basis of the submarine fleets was the semi-hull boats. In this type of ships, another one, more lightweight, was built on top of a strong hull. In the lower part of the submarine there was no light hull (therefore, the boat was called the one and a half hull). Boats of this class had an average displacement and could operate on the high seas. However, these ships were ill-equipped for action on enemy shores. Thus, the Germans initially focused on the construction of medium-range submarines, which from the very beginning of the war did not allow them to actively operate on the sea communications of the Entente countries and seriously impede the transfer of troops from England to the continent, or from colonies and dominions to France.
The third type of submarines, double-hulled, had a light hull along the entire circumference of the strong main hull, which ensured better driving performance compared to other types of submarines. Such submarines had a displacement of more than 650 tons and were considered "oceanic". They were intended for military action on the sea communications of the enemy. These submarines began to enter service after the start of the war, beginning with the 1915 year, as they were developed taking into account the experience gained in the first months of the war. On the surface, they could travel up to 10 thousands of miles. The diving range was much shorter: from 30 to 100 miles with an economical turn of 3-5 nodes. By the end of the war, submarine cruisers with a displacement of up to 2000 tons were built in Germany.
The speed of such submarines was on average equal to 12-14 nodes, although the maximum reached 17-18 nodes. For movement above water and under water different engines were used. In the surface position, the submarines used internal combustion engines: diesel, kerosene, gasoline. On the English submarines of type "K" installed a steam turbine. For the underwater movement of the boat of all types and designs used an electric motor with batteries.
The depth of the submarine submersible pre-war construction was 30 meters, but later submarines could fall to a depth of already 50 meters. The dive speed varied: the maximum reached 90 seconds, but during the war emergency diving devices appeared that reduced the dive time to 30-60 seconds.
During the war, the mine-laying class was also distinguished, which were used to set mines. These were ships of various sizes: from 170 to 1200 tons. Early prewar versions could accommodate up to 12 mines, later and more advanced ones could take on board already before 72. There was no torpedo armament on minefields (small boats) or it was reduced to a minimum (on large ships).
The main weapons submarines were torpedo tubes (4-8 devices on large submarines, 1-2 - on small ones). Pre-war torpedoes were driven by a pneumatic engine that operated on compressed air, and could reach speeds up to 43 nodes. Depending on the speed limit, the torpedo could be fired over a distance of 6 kilometers. Artillery guns before the war were mainly equipped only with large “oceanic” double-hulled boats.
German submarine U-148
It is worth noting that the methods of anti-submarine warfare were then in their infancy. Submarines were planning to destroy artillery fire or ram attack. A so-called anti-submarine zigzag was used against submarine attacks, when the ship, going on the high seas, constantly changed course. In addition, in parking lots in the port stretched anti-torpedo networks. That was all they could do at the start of the war. In addition, invented indicator (signal) networks were tested. They were made of thin durable steel cable with floats from kapka or in the form of glass balls. Being hooked on the boat, the net was dragged behind it, and the floats on the surface unmasked the movement of the boat. With the beginning of the submarine war, the British decided to partition off the English Channel, and in addition, large minefields were placed there.
Thus, anti-submarine weapons had to be invented in a hurry right during the war. On December 20, 1914, the “Commission on Submarine Attack Affairs” began its work in Great Britain, the task of which was to develop means and methods of anti-submarine warfare. Part fleet special patrol vessels began to be introduced, they were armed with guns and had to conduct patrols. Old destroyers were commissioned from the reserve, fishing trawlers were armed. The commission also commissioned trap ships. They were of two types. The first is a fishing vessel or trawler, followed by a submarine in tow in water. When the German ship was caught on bait and approached the trawler, an English submarine torpedoed it.
Another type of submarine trap was trading, most often sailing ships, on which medium-caliber guns or torpedo tubes were installed and camouflaged. When the German submarine resurfaced and demanded that the crew of the bait ship leave the ship, part of the crew rushed to the lifeboats, painstakingly portraying panic, while the second patiently waited for the enemy to come closer to shoot him point-blank from guns or sink to torpedo. The service on such bait ships, of course, was considered very dangerous, the crew was staffed only from volunteers. It happened that the German boats attacked such vessels, without emerging at all or from a considerable distance. However, the effectiveness of such trap ships was minimal. Thus, the German U-40 and U-23 submarines were killed, sunk by the British C-24 and C-27, respectively, and the U-41 submarine fell into the trap of the second type.
The first type of anti-submarine weapons were towed mines, which were in service with England, Germany, Italy and France. They were invented back in the nineteenth-century 60 by British officers, the brothers Harvey, and they were planned to be used for defense against rams. Mina of this particular design, the first submarine "Hanley" sank "Husatonic". However, the effectiveness of a single mine was very low, so the British fleet invented an improvement - a special anti-submarine trawl with four mines was created, which the patrol ship dragged along under water. There was a special device that allowed to regulate the depth at which the charges followed. The girth width was 150-180 meters. But this weapon did not bring much benefit. During the war years, only four submarines were killed by such a device.
Depth charges have shown much greater effectiveness in the fight against submarines. The first experimental samples were created by the end of 1914, the British. But they began to enter service in small batches of 100 units per month only in 1915 year. Only by 1917, with the growth of the threat from the German submarine forces, bomb production began to increase and by the end of the year reached 4 thousands of copies.
As previously noted, the first months of the war, the tasks of the submarines of the fleets of the warring powers were the same: reconnaissance, patrolling, search for the enemy, hidden installation of mines. The results of such activities were minimal. The exception was the overwhelming success of Captain Otto Veddigen, who sank 22 on September 1914 in the course of an hour, with three British cruisers in a row.
The German command in August organized a raid of the 1 submarine flotilla to test the capabilities of submarines and reconnaissance. The 10 submarines were ordered to go 300 nautical miles to the Orkney Islands (north of Scotland, where the main base of the British Navy Scapa Flow was located), then return to the base on the island of Helgoland. According to the results of the operation, one submarine went missing, another was sunk by British ships (rammed), the rest reached the target and returned to the base. After this, certain conclusions were drawn in Germany and England. The Germans realized that they needed more powerful, capable of long-time autonomous navigation of the submarine, which they immediately began to create and manufacture, in carrying out long operations in the North Sea. For the British, the appearance of enemy submarines in such a remote area was a complete surprise. Fearing their attacks and the loss of ships of the linear fleet, the British Admiralty found the fleet base at Scapa Flau unsafe, it was decided to temporarily move the fleet base to Lough Yu on the west coast of Scotland.
The problem of international law
In accordance with the Paris Declaration of 1856, the blockade could be provided with the forces necessary to block access to the enemy coast. Thus, all ships under the flags of neutral countries, carrying absolute smuggling and following in the ports closed by blockade, were subject to capture.
In May, 1899, at the Hague Conference, Russia attempted to ban the creation of underwater weapons as potentially dangerous for the civilian merchant fleet. However, the British "torpedoed" this proposal. At the Hague Conferences of 1899 and 1907, the basic rules, laws and customs of warfare, both land, air and sea, were established. According to these rules, it was impossible to sink or detain a neutral ship if there was no military smuggling on it. If smuggling was found, it was necessary to ensure the safety of the crew of the vessel, disembarking it on rescue ships, and only after that it was allowed to sink the ship. As a result, in 1914, the existing norms of international law allowed the belligerent to seize and destroy property, if it was intended, directly or indirectly, for the enemy, and if the safety of passengers and crew was ensured.
The shipments defined by the 1909 London Declaration of the Year were divided into three categories. Absolute contraband, that is, any military property. At the same time, it didn’t matter whether the cargo should be sent directly to the enemy port or transshipped in a neutral country. Under current international law, such goods were subject to immediate confiscation after the relevant statement of the prize court. Conditional smuggling - goods that do not have a direct impact on the enemy’s military capabilities. These included food, fuel, precious metals, etc. They were allowed to seize if they went directly to the port of the enemy. All the rest belonged to the third category of free cargo. The warring parties did not have the right to seize or detain them, even if they went directly to the enemy port. At the same time, the London Declaration of the 1909 of the Year was not ratified by England, which considered that some of its provisions were to the detriment of its interests. As a result, Britain, not bound by the terms of the declaration, could base the blockade rules on previously adopted laws and ignore international law.
20 August 1914, the allies declared that conditional smuggling was subject to the same treatment as absolute. Since 21 September 1914, the conditional smuggling list has been significantly expanded, including copper, lead, glycerin, iron ore and rubber. October 29 added wire bays, aluminum, sulfuric acid and a number of other items to the list of absolute contraband. Since then, both lists have been subject to regular review and expansion.
It is clear that the differences of London and Berlin on this issue were inevitable. Germany stated that the UK, not submitting to the London Declaration and establishing its own, too harsh blockade rules, violates international laws. Other countries, mostly neutral, also denied the right of the royal navy to stop and inspect ships on the high seas. The world community demanded "freedom at sea!". This view was held by the United States. The American economy is largely focused on exports to Europe, in particular to Germany, and the US industry has suffered significantly from the blockade of ports in Western Europe. The British outwardly agreed with the opinion of Washington, but they constantly followed the path of strengthening and tightening the blockade of Germany, which violated the interests of neutral countries. In November 1914, the British government declared the entire North Sea a zone of military operations, as a result of which all ships of neutral countries to Norway, Denmark, Holland and the Baltic countries were to follow the Canal, making it much easier for the royal fleet to search and search. The free movement of neutral merchant ships has become impossible here; every ship that was not considered with this decree was threatened with death.
As a result of the measures taken by the British government, direct and intermediary trade with Germany was killed, which became impossible as a result of eliminating the distinction between the concepts of absolute and conditional smuggling. The British prevented the importation of even those goods that were not smuggled, they were unloaded on the shore under the pretext that smuggling could be hidden among them, after which the goods were either requisitioned or delayed with reference to the prohibition of importation and then sold. Also, in order to preserve at least some maritime trade that the British fleet could block, neutral states were forced to submit to the requirements of England and impose a broad ban on the export to Germany. Economic circles in neutral countries were forced to curtail relations with Germany.
Therefore, the German command began to look for an opportunity to disrupt the sea communications of England, its trade. The surface raiders intended for this business have already died. Then in Germany, discussions began on the use of submarines against merchant ships. In November, the German command of 1914 noted: “Our coast is not blocked, therefore our trade with neutral countries, since we are not talking about smuggling, could by itself go on quietly, however, all trade on the North Sea coast stopped. England exerts strong pressure even on our neighboring countries, seeking to prevent the sale of goods necessary for the conduct of war to us. She tries especially energetically to prevent the delivery of vital supplies through neutral countries. The point here is not only in the import of food for our army, but also in the intention of England to starve the entire German people. At the same time, England is completely disregarded with the provisions of international law, since vital supplies are only conditional contraband and are only to be seized if they are intended to supply the army. ... If England seeks in this way to destroy our trade, then we would only commit an act of fair retribution, in turn, embarking on a war against English trade and applying all the means at our disposal. Further, if England is not considered with the interests of neutral countries, then we, in waging the war, have not the slightest reason to impose any restrictions on ourselves in this regard. We will deliver the most sensitive blow to England if submarines damage its trade. We must, therefore, use this tool, applying it in accordance with its peculiar properties. The more vigorously the war is waged, the sooner it comes to an end, the fewer human lives will be sacrificed and the less good will be lost. The submarine cannot therefore spare the crews of the steamers, and they will, therefore, have to die together with the ships ... ”
Most of the Admiralty, led by Tirpitz, the chief of the naval headquarters Hugo von Pohl and the commander of the submarine fleet Bauer, favored bypassing part of the restrictions. They noted that restrictions on methods and means of warfare against merchant ships are only valid for surface ships, and do not apply fully to submarines. On the submarine is a very small crew, which cannot normally search the ship or check the cargo. In this case, as soon as the submarine emerges, she herself can become a victim even for a merchant ship, which can be used by a ram. In addition, the trader, taking advantage of the speed, is fully capable of trying to escape. Thus, supporters of unrestricted submarine war were in favor of allowing German captains to drown trade without checking the cargo, in case the “merchant” disobeys.
According to pre-war calculations, which one of the ideologists of submarine warfare, Captain-Lieutenant Blum, conducted, 200 submarines were required to completely paralyze the merchant shipping of England Germany. But Germany did not have a quarter of the required number of submarines. An additional large-scale construction was launched. Part of the naval officers led by Grand Admiral Alfred Tirpitz, the head of the German Admiralty, believed that the current size of the submarine fleet would be enough only for the Thames blockade. They pointed to the low effectiveness of waging war in the Atlantic Ocean by such a small number of boats and the inability to establish a tight ring of blockade. Therefore, Tirpitz proposed to postpone the start of the underwater war until the replenishment of the fleet. But his opponents insisted on the immediate intensification of the actions of the submarine fleet. As a result, the point of view of the radical part of the party of supporters of unrestricted submarine war, led by the head of the naval headquarters von Paul, won.
Opponents of an unlimited underwater war were politicians headed by Chancellor Betman-Golveg, who until a certain time was supported by the army generals. The General Staff hoped to achieve victory on land and did not believe in the possibility of achieving decisive success with actions at sea. Politicians believed that the risk of involving third powers on the side of the Entente as a result of an unrestricted submarine war (especially the position of America was important) was too high and not worth the opportunities that such tactics gave. The Chancellor believed that such an event as an underwater blockade could be carried out without any dangerous consequences only if the martial law of Germany on the continent becomes so strong that it will not cause doubts, and it can be considered that the danger of transition of neutral states to the side of our enemy will be excluded. Now this moment has not come yet. Thus, the Chancellor hinted that you first need to achieve success in the land war, and then you can think about fighting England at sea.
Kaiser Wilhelm II hesitated. The situation changed when it became apparent that the German army would not achieve quick success on land. By the beginning of 1915, it became clear that the war had dragged on indefinitely. In the war of attrition, the possibilities of the economy, of military production, came to the fore: can the powers uninterruptedly supply their armies and people with everything they need, from weapons and ammunition to basic necessities and food. The theories of the German submariners, who promised to deprive England of maritime trade and inflict a decisive defeat on the forces of a single submarine fleet, ceased to seem like a fantasy in this situation. And the German command decided to "take the risk." The final decision on the beginning of the first stage of an unlimited underwater war was made on February 2 1915 at a government meeting, and on February 4 it was approved by the Kaiser.
4 February 1915, the German Emperor Wilhelm II decided to declare the waters around Britain and Ireland, along with the English Channel theater of operations, which actually meant the beginning of the naval blockade of England. This was the first blockade in stories naval wars, which was carried out with the help of underwater forces. 8 February 1915, the commander of the submarine fleet Bauer issued a directive prescribing the start of the submarine war against the merchant fleet.
Germany announced the main principles of the blockade. First, since February 18, any enemy vessel found in this area was to be destroyed. The Germans reported that they would not always be able to warn the crew and passengers of the impending danger. Secondly, German submarines were allowed to attack neutral ships in these waters, since the British government recommended its ships to use the flags of neutral states. At the same time, sea lanes north of the Scottish Islands, in the eastern part of the North Sea and along the Dutch coast, in a strip of width 30 miles, were declared free for navigation.
Submarine commanders were ordered to conduct submarine warfare on their own. The primary objectives were considered the largest and most capacious vessels, following to Britain under the English flag. At the same time, submarine flotilla commanders were instructed to exercise caution, spare neutral ships, first finding out their nationality. To determine the nationality of the merchant, the German submariners were asked to pay attention to the marking of the vessel, which course it was taking, the silhouette, the behavior of the team. It is clear that with such criteria for determining the probability of error was very high. Already 19 February 1915, the submarine U-19, sunk the first neutral ship, the Norwegian ship Beldridge.
12 February, the United States in a diplomatic note demanded that Germany guarantee security for its merchant ships and its citizens sailing on any peaceful foreign ship. Berlin gave an answer in which it was noted that underwater warfare was the forced response of Germany to the British blockade, which could lead to famine. Nevertheless, the German government guaranteed the safety of American citizens, in exchange for offering the United States to help ease the blockade. Washington asked the British government to open access to Germany for merchant shipping, which would supply food to civilians. However, the British in response only increased the blockade.
Chief of the Naval Staff and Commander of the German Open Sea Fleet Hugo von Paul
To be continued ...