Page 28 - History of War - Issue 25-16

SUB HUNTERS

THE WAR UNDER THE WAVES CORVETTE
Dubbed the “cheap and nasties” by Churchill
because they were cheap to produce and
supposedly nasty for the U-boats, these
INCREASINGLY SOPHISTICATED CATALINA FLYING BOAT smaller warships were based on whaling
TECHNOLOGY PLAYED A KEY ROLE ships, whose engines were thought to be
IN DETERMINING WHO EMERGED ideal for chasing subs, which they could then
VICTORIOUS FROM THE DEADLY DUEL attack with their four-inch guns and depth
ON THE HIGH SEAS charges. Mass produced and rushed into
service with the then tiny Royal Canadian
Perhaps more than any battle in history, Navy, they struggled badly in the rough seas
the one for control of the Atlantic shipping
and violent weather of the North Atlantic.
lanes during World War II demonstrated the
importance of technology in warfare. Since
humans i rst began engaging in organised
conl ict thousands of years ago, the victors
have almost exclusively been those with
the technological edge. When World War II DRIFTING/FLOATING
began, it was the German navy, which had LEIGH LIGHT MINES
been preparing for war for years and who in
Dubbed ‘the dustbin’ because of its
Admiral Dönitz had a master strategist, that shape, this 22-million candlepower,
looked best prepared for victory. However, 24-inch retractable searchlight was
Britain, along with its ally Canada and later slung underneath the fuselage of
the US, developed an astonishingly rapid and sub-hunting Allied aircraft. When an
sophisticated response to the U-boat threat unsuspecting U-boat was suddenly
that ultimately proved irresistible. pounced upon from above while
Dönitz insisted on a top-down command travelling on the surface, the light was
structure, ensuring he micro-managed every switched on and the sub illuminated.
single engagement with Allied shipping from This not only made it easier for the
his war room, which from the summer of 1940 attacking aircraft to hit it, but it also
was in Lorient, Western France. This obsessive blinded the U-boat’s crew in the i rst
planning ultimately made his submarine crews few vital moments of the attack as they HEDGEHOG
vulnerable to intelligence leaks. With the struggled to respond. This forward-i ring mortar spat groups of 24 missiles up
cracking of Germany’s supposedly unbreakable to 250 metres from the deck of a corvette or a destroyer
Enigma code in 1941, which Dönitz used to as it chased down a submerging U-boat. Its shells would
communicate with his U-boat commanders only explode if they actually made contact with the evading
U-boat, which meant the sonar wasn’t disturbed if the shell
and move his wolf packs around his maritime
maps, the fate of Germany’s U-boat l eet was missed. More deadly than depth charges, which relied on
hydrostatic shockwaves to score a kill, the hedgehogs’
sealed. Then, with an array of ground-breaking missiles would punch a hole directly into the U-Boat’s hull.
detection devices and bespoke weaponry, it
was eventually destroyed.

Above: Ramming U-boats was another tactic used by
allied naval commanders – often resulting in considerable
damage to their own ships
Depth charges were i red off the side RISING MINE
of Allied warships. The underwater
explosions they created broke the
U-boats’ hulls with shockwaves

INTELLIGENCE
The work done by Alan Turing and his
SONAR team of code breakers at Bletchley
The British had developed sonar before the war, Park was key to the Allied victory, not
using directional sound waves to ‘see’ underwater. just in the Battle of the Atlantic but the
These bounced off the U-boats and were heard entire war. Their cracking of the Enigma
back as an echo. The quicker the return of the code in 1941 enabled the Royal Navy’s
echo, the closer the submarine. Listened in to by Western Approaches Command to
a radio operator, they had a range of about 275 effectively see every play Dönitz was
metres – ideal if a submarine was close, less so if making as he was making it, and
it was at the limit of its torpedo range, which, at simply steer the convoys away from or
the outbreak of war, was about three kilometres. around his lurking wolf packs.

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