American turkey shoot; Flash back.

Byline: By Steven Guy of Merseyside Maritime Museum 

WHEN the United States entered the war in December 1941, the German U-boat submarine offensive entered a new phase which led to the underwater menaces losing the initiative and then the battle.

First the Americans had to learn a hard lesson. U-boat captains were ordered to move to the US east coast and immediately created mayhem.

Within weeks the huge losses of ships and supplies suffered by the Americans threatened the whole Allied war effort.

It was six months before the United States finally introduced its own coastal convoy system. This quickly ended what the U-boat crews called their "American turkey shoot" which had cost 149 ships, including many vital oil tankers, totalling well over two million tons.

From mid-1942 more British, Canadian and American naval escorts became available.

Some 150 corvettes were in service along with new sloops and frigates. Convoys usually had an escort of at least six ships.

However, many Atlantic escorts were diverted at this time to support Arctic convoys and the Allied landings in north Africa. The escorts themselves were much better equipped than their predecessors.

Examples of equipment and weapons used to beat the U-boats are on display in the Merseyside Maritime Museum's Battle of the Atlantic gallery.

A large blue metal box with dials and knobs was known among crews as a Huffduff - a HF/DF or high frequency direction finder. These were used alongside radar and the improved Asdic equipment to more efficiently detect U-boats.

A small bomb was one of 24 which bristled in an anti-submarine mortar appropriately known as a Hedgehog. These were all fired at once and plunged into the sea over a wide area, with great effect.

Radar spares were carried by Lieutenant E C Leisgang, of the South African Naval Force (SANF) who was Inspector of Naval Radar in Liverpool for most of the war.

The last major crisis of the Battle of the Atlantic came in April - May 1943 when, in a series of hard-fought convoy battles, 27 U-boats were sunk for the loss of 24 merchant ships.

At the end of May there was an uneasy underwater peace when all U-boats were withdrawn from the north Atlantic convoy routes for six months.

U-boat command had decided to regroup and concentrate on developing new submarines and weapons.

Although still a menace to Allied shipping, especially in British and European coastal waters until the very last days of the war, the U-boats were never to regain the upper hand in the Atlantic.

Merseyside Maritime Museum is open seven days a week, admission free.

CAPTION(S):

HUFFDUFF: A high frequency direction finder; MORTAR ON BOARD: An anti-submarine mortar launcher, known as a Hedgehog. Inset, one of the motars; SPARES: For a World Ware II radar system