1. Battle of the Atlantic

2. Britain’s Need Million tons of material per week 3,000 merchant ships
2,500 were at sea very day
Imports came from all over Empire
Atlantic crossing most important because of USA

3. Fair Game
10 hours after declaration of war U-boats began attacking civilian & military shipping
Passenger liners - Athena
Merchant shipping
Royal Navy vessels

4. Was Britain Ready? Underestimated German U-boat scheme
More concerned with emerging surface vessels
Britain’s naval program was tailored to surface warfare
Over confidence in ASDIC

5. Early Royal Navy Losses
Aircraft carrier Courageous - Sept 17, 1939
518 lives
Battleship Royal Oak - Oct 14, 1939
In Scapa Flow
833 lives
Aircraft carrier Ark Royal - Nov 13, 1941

6. Wolf Packs Admiral Karl Donitz Champion of U-Boats
Most influential of Naval staff
Navy as a whole was not politically powerful

7. Karl Donitz

8. Wolf Packs 46 U-boats at outset of the war
Early in the war, Germany was replacing subs 2 per month - kept up with losses
Not all were ocean going vessels - coastal

9. Watch it Go Down

10. Wolf Packs
June ,000 tons
Hunting individually was inefficient
Donitz developed pack strategy
U-boats would spread out along shipping lines
Once one had made contact - the captain would contact HQ

11. Life on a U-Boat

12. Life on a U-Boat

13. Wolf Packs Sub would shadow convoy Others would converge
They would attack
Invasion of Western Europe interrupted plans
Sept - Nov “Happy Time” for packs

15. Survivors

16. Torpedo

17. The Atlantic

18. Raiders & Marauders Surface Attacks Pocket Battleships
Graf Spee, Scharnhorst, Deutschland, Scheer
Disguised, alone
Sunk 130 ships

19. Graf Spee

20. Bismarck

22. Raiders & Marauders Bismarck and Prinz Eugen put to Sea May 1941
Hunted and killed
German surface navy no match for the Royal Navy

23. Convoy Early they were poorly organized and protected
freighters
Slow moving
Corvettes were escort vessels of choice
Much like shepherds

24. Liberty Ships 1939-1940 The US built 102 ships 1942 they built 646
By 1943 they were producing 140 ships a month

25. Liberty Ships Prefabricated components
441 feet long, 11 knots, range of 17,000 miles, $2 million per hull
Could carry 10,800 tons of cargo
“Ugly Ducklings”

26. Liberty Ships Components were built all over the country
Transported to Pacific coast by rail
The biggest cranes in history lifted the components into place
Tugs pulled the ships to a finishing area to make way for new hull
1.5 million people working in the yards

27. Technology ASDIC improved
Radar installed on vessels to find surfaced U-Boats
Huff-Duff allowed RN and RCN to track U-boat radio transmissions - triangulation
Star shells

28. Depth Charge

29. Technology Depth charges
Statistical study allowed for larger convoys over 60 ships at times
Air power
Hedge hogs

30. Airpower

31. Hedge Hog

32. Hedge Hog

33. Turn of the Tide Tonnage losses peaked in June’ 42 - 830,000 tons
By August 1943 losses were down to 150,000 tons
By May 1945, 3/4 of submariners had been killed