The creeping attack was an anti submarine measure developed during the

Battle of the Atlantic The Battle of the Atlantic, the longest continuous military campaign in World War II, ran from 1939 to the defeat of Nazi Germany in 1945, covering a major part of the naval history of World War II. At its core was the Allies of World War II, ...

World War II World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

. It was first used by 36 Escort Group of the

Royal Navy The Royal Navy (RN) is the naval warfare force of the United Kingdom. It is a component of His Majesty's Naval Service, and its officers hold their commissions from the King of the United Kingdom, King. Although warships were used by Kingdom ...

after being developed by the Group's commanding officer, Captain "Johnnie" Walker. The problem addressed by Walker in the tactics then in use was that

ASDIC Sonar (sound navigation and ranging or sonic navigation and ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, measure distances ( ranging), communicate with or detect objects o ...

, the active sonar means to search for and find a submerged submarine, searched forward, while the main weapon to attack it, the depth charge, was released or projected from the stern. This led to a loss of contact in the final run up to target as the attacking ship passed over it, giving the

U-boat U-boats are Submarine#Military, naval submarines operated by Germany, including during the World War I, First and Second World Wars. The term is an Anglicization#Loanwords, anglicized form of the German word , a shortening of (), though the G ...

a chance to move at the last minute and evade damage. The more skilled or experienced U-boat commanders became adept at predicting the points at which the escort sped up to attack, and when they lost ASDIC contact, and were able to move aside while the charges sank to their depth. The creeping attack used two ships; one to remain stationary and keep in ASDIC contact, detectable by the target submarine, and guide a second ship onto the target. The second crept up slowly, running as silently as possible and without using ASDIC to avoid detection by the U-boat, and released its depth charges when the first ship, in ASDIC contact, signalled it was positioned correctly. The method required practice to get right, and was expensive of time and resources, but was devastatingly effective. 36 EG, and Walker's next group, 2nd Support Group, were the most successful U-boat killers of the war. The advent of more sophisticated ASDIC systems that held contact closer in, together with forward-throwing weapons such as

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and

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, also overcame the loss of contact that made the creeping attack necessary, but it remained in use throughout the campaign.

Sources

*Burns, Alan: ''The Fighting Captain'' (1993) *Milner, Marc. ''The Battle of the Atlantic'' (2003). (UK): {{ISBN, 1-55068-125-7 (Canada) Naval warfare tactics Anti-submarine warfare Battle of the Atlantic