WORLD WAR I.
|The supreme enemy effort, in the First World War, was concentrated on the submarine campaign, supplemented by commerce-raiding capital ships and mines. In 1915 the Germans began their first full-scale submarine campaign, their best known victim being the Cunarder 'Lusitania'. 1,198 people died, including over 100 Americans. The United States, still a neutral country protested and the Germans reduced their indiscriminate torpedoing.|
By 1918, the shortage of food in Britain became serious enough for the government to impose rationing. But the British suffering bore no comparison with the misery of the German people. They had endured blockade since the beginning of the war and by 1916 (the year the German potato harvest failed) they were running short of food. So ultimate British control of the sea meant no spectacular victories, but slow starvation of the German people.
British M Class submarine with 12" Gun weighing 50 tons and firing a projectile of 850 lbs.
WORLD WAR II.
The story is a dramatic struggle for supremacy between the convoy escorts, both surface and air and the U-boats. Despite Hitler's order on the outbreak of war that his U-boats were to wage war in accordance with rules laid down in the Hague Conventions, U-boats often approached on the surface without detection to attack convoys in darkness, causing heavy losses, on 4 September1939 the passenger liner Athenia (13,000 tons) was torpedoed by U-30. 128 of the passengers and crew being lost. From then on the German High Command moved towards unrestricted submarine warfare, although the term was not actually employed until after the United States entered the war. So great was the havoc wrought, among warships and supply vessels, that there were black periods when it looked as if the U-boats were going to win the war for Germany. These attacks could only be overcome by more escort vessels and, in due course, the corvette and frigate were developed. Not differing greatly from sloops, they possessed advantages in respect of handiness and economy of personnel, and, most important of all, could be built quickly and in numbers. They carried depth charges and guns.
Germany began the war with 56 U-boats of which only 46 were operational, and of these 30 were small vessels of 250 tons capable of operations only in British, coastal waters. On the outbreak of war 21 U-boats were at sea disposed from the North of Ireland to the Straits of Gibraltar, but this number was soon reduced to about half by the need for boats to return for rest and refit. During the first 4 months of the war 9 U-boats were sunk, and although there were plans for a great expansion, it was not until July 1940, when finally hope of making peace with Britain, was abandoned that Hitler authorised the programme to be implemented. This delay was to prove most fortunate for Britain. In the early stages of the war 2 German submarines, U-29 and U-47, achieved two remarkable successes by sinking the carrier Courageous (22,500 tons) in the chops of the Channel on 17 Sept. and the battleship Royal Oak (29,l50 tons) at anchor in Scapa Flow on 14 October, respectively. The last named disaster emphasised the weakness of the defences of the Home Fleet anchorage, which were not made good until the following year. Despite the activities of the U-boats and the threat of air attack, both of which were later to take a heavy toll of shipping, by 7 October 161,000 men with 24,000 vehicles and some 140,000 tons of stores were transported to France without loss
Against submarines the early confidence in asdics was at first misplaced. The apparatus could certainly detect submerged U-boats under favourable conditions, but it was not designed to seek out the enemy on the surface at night. It was not until the development of radar that the measure of the submarine menace could be taken, when they were once more subject to detection, whether on the surface or submerged. The navy and coastal command of the R.A.F. worked in close co-operation to defeat the U-boats, and eventually escort carriers were included in nearly every convoy. The majority of these were built in the U.S.A. under lend-lease and returned at the end of the war.
Towards the end of the war Germany had developed a device where, by fitting U-boats with a Schnorkel (or breathing device), they could remain submerged for extended periods, and could thus escape both aircraft and the radar screen. Fortunately the war ended before this invention could influence the battle of the Atlantic to any great extent. They also began to employ a new type of U-boat with a displacement of only 230 tons, which were able to operate in British coastal waters again, for the first time since 1940. The fitting of the schnorkel and the employment of these small submarines brought about a stalemate in the war against the U-boats, since unless they disclosed their presence by a hostile act, they were unlikely to be detected, especially because of the strong tidal streams in British waters. Aircraft were thus robbed of their usefulness.
During the last 5 weeks of the war the U-boats were specially active off the North and East coasts of Britain, and during the period of this inshore campaign, between 1 January and 8 May 1945, 38 merchant ships were lost at a cost to the enemy of 32 U-boats. The U-boat arm of the German navy reached its peak strength in March 1945 with a figure of 463, for it was not until this month, when the Allied armies crossed the Rhine, that production was seriously affected by the bombing to which the building yards for so long had been subjected.
During the war 1162 U-boats were constructed, and losses amounted to 784 through various causes, but principally as a result of attacks by escort vessels and aircraft, which accounted for 584.When on 4 May they were ordered to cease hostilities, there were 45 U-boats in the Atlantic, of which 33 were on passage and 12 in British inshore waters.
BRITISH & ALLIED SUBMARINE OPERATIONS
The part played by British and Allied submarines in the war in Europe, the Mediterranean and East Indies deserves special mention. When war broke out in 1939 there were 69 British submarines in commission, and they were assisted by several. French Dutch, Greek and Polish vessels which rallied to the Allied cause. During the German invasion of Norway, the submarines on patrol in the Skagerrak were the only vessels in a position to interfere with the movement of German troops, which they did with conspicuous success, sinking 5 transports for the loss of 3 of their number. But their greatest successes were obtained in the Mediterranean where between June 1940 and the end of 1944 they sank 286 ships with a tonnage of 1,030,960, as well as 4 cruisers, 9 destroyers, 8 torpedo boats and a corvette. They made a major contribution to the defeat of the Axis armies in North Africa by their constant harassment of the supply line between Italy and the Libyan bases. Their losses in this area were severe, amounting to 51 boats of which 45 were British, 4 Greek and 2 French. They also played an important part in the destruction of Japanese shipping in the East Indies, and in the last 6 months of 1944 they sank 16 ships with a tonnage of 35,356. Later they moved to West Australia where in co-operation with the submarines of the U.S. Navy they swept the sea clear of Japanese. merchantmen. During the war 120 British submarines were built, and total losses amounted to 90.