The Battle of the Atlantic

A Summary of the Longest Campaign of World War II

1939-1945

The Strategic Situation

• Britain needed supplies to fight the war

• Convoys of ships brought oil, wood, aluminum and finished goods like planes and tanks

• Without supplies Britain could not continue the war

The Battleground

The Nazi Strategy

• The Germans tried to cut off supplies to Britain by sinking transport ships

• They used some raiding vessels (cruisers and battleships), but primarily U-boats (submarines)

Allied Strategy• The Allies tried to protect the transport ships in

three ways:

1. Convoys – large flotillas of ships

2. Escorts – Destroyers and Corvettes deployed to protect the convoys

3. Air cover – limited to within a few hundred miles of Canada and Britain

• Allied ships feared the mid-Atlantic where there was no air cover

Allied Convoys

German Tactics

• Groups of U-boats would hunt for convoys in “Wolf Packs”

• U-boats would maneuver in front of the convoy and then submerge – surfacing in the middle of the convoy

• German subs would first use deck guns to sink boats – if a threat existed they would use torpedoes instead

U-Boat Attack

Convoy Tactics

• Allied warships would look for U-boats using “ASDIC” – a early form of Sonar.

• If a surfaced U-boat was detected, warships tried to ram them

• If the U-boat submerged, Allied warships would drop “depth charges” – barrels of explosive set to go off at different depths.

• Planes would also attack and drop depth charges

Convoy Tactics

The Battle

• June 1940 – February 1941 “The Happy Time” for the U-boats – Hundreds of ships sunk

• March 1941 – December 1941 – Allies use ASDIC, HF-DF radar + better tactics to thwart U-boats -- British break German Code – “Enigma”

• Jan., 1942 – July 1942 – “Operation Drumbeat” – U-boats attack USA shipping – easy targets

• July 1942 –Feb 1943 – Wolf Pack in Mid-Atlantic

• April-May 1943 – Climax of the Battle – U-boats suffer enormous losses -- remain a threat until the end of the war

Surface Raiders

German Battleship Bismarck

British Battleship Hood

Swordfish Dive bomber

Conclusion

• Allied victory in the Atlantic was essential to Allied victory in Europe

• By defeating the U-boat and Surface Raider threat, we were able to win the war

Your Task: Convoy Puzzle

• You are to deploy your convoy in the best formation to protect it from the Nazi U-boats that are hunting it. You must create a diagram AND explain it in 3-5 sentences

• You have 20 transport vessels that go about 10 knots (11mph)

• You have one destroyer (small warship with depth charges & ASDIC) as a command vessel

• You have two corvettes (very small escort vessels with depth charges & ASDIC)