War and the transformation of British society c1903–28
Key Topic 1: The Liberals, votes for women and social reform
Key Topic 2: The part played by the British on the Western Front
The BEF and 1914. Overview
The end of the war. Overview
Key Topic 3: The home front and social change
DORA, censorship and propaganda. Overview
Recruitment and rationing. Overview
The part played by women. Overview
Key Topic 4: Economic and social change 1918–28
The changing role of women 1918–28. Overview
The General Strike of 1926. Overview
Measures introduced to cope with the U-Boat menace during the First World War
The German's had a large and powerful navy during the First World War but were unwilling to risk it being destroyed by the Royal Navy. After the Battle of Jutland the German fleet retreated to the ports and played little part in the war. However the Germans were keen to inflict damage on the Royal Navy and merchant shipping. To do this they made use of submarines (U-Boats).
In the early stages of the war the U Boats operated largely within the North Sea and British waters. U Boats carried several torpedoes and initially even allowed crews of merchant ships to leave the vessel before sinking it. As merchant vessels began to be armed and escorted the tactics changed and a more aggressive approach was taken.
On May 7th, 1915 a German U Boat fired upon and sank the US Liner, Lusitania. The sinking of a passenger ship very nearly brought America into the war. German policy changed again. Merchant vessels were issued warnings and checks were to be carried out before a ship was to be sunk. However this policy was very shortlived as it meant that little damage was done to merchant shipping.
In 1917 the German U Boat fleet resumed unrestricted attacks on shipping. Any vessel going to / from Britain was seen as a legitimate target, irrespective of the ships nationality. The impact was devastating. The data below shows how much shipping was lost as a result of this new campaign:
February 520,000 tons sunk
March 560,000 tons
April 860,000 tons
May 616,000 tons
June 696,000 tons
July 555,000 tons
The British response to the increased losses was quick and relatively effective. Merchant vessels were organised into convoys that were protected by the Royal Navy. Minefield were laid to try and prevent the U Boats from getting into the North Atlantic. Aircraft were used near the coast to spot and attack U Boats. The convoys sailed in a 'zig zag' pattern rather than in straight lines, to make it harder for U Boats to get an easy shot. New technologies were also adopted as sonar and depth charges were added to many vessels.
UBoat.net - detailed account of submarine warfare in the First World War.
BBC - The U-Boat theat.
Wikipedia - Naval warfare of World War One.