Realistic patrols

Stiebler · 05-01-11, 02:18 PM

Ah, the joys of dabbling in statistics!

The figures that you quote (8/39 - 8/40; presumably the last days of the month) have little meaning of themselves.

Firstly, U-boats were mostly deployed for minelaying around Britain in the first months of the war, and sinkings from mines are probably not counted in Blair's figures.
Secondly, many of the U-boats were of the tiny Type II, with very limited range and torpedo capability (and no deck gun). The figures you quote for average patrol times tell their own story: a duration of just 23.6 days is laughably short.
Thirdly, U-boats had to surface and stop individual merchant ships according to the prize-rules then extant. This was a slow and dangerous business, especially if enemy aircraft were around.
Fourthly, many U-boat torpedoes at this time were hopelessly unreliable, especially if used in shallow waters or high latitudes.
Fifthly, Blair's chosen time span includes the German invasion of Norway, when the entire German navy, including all available U-boats, was directed to Norwegian (ie, northern latitude) waters for the purpose of protecting the German invasion fleet from the British Navy. The U-boats found virtually no targets - and when they did fire, their torpedoes were almost all defective.

You do not state either your time period, for running up regular totals of 30,000 tons plus, or your U-boat type. But if you had a VIIC or, especially, a IXB boat in late 1940, you could expect to attain a very large score, depending on area. Hessler (U 107) sank nearly 100,000 tons on just *one* patrol in mid Atlantic during 1941. Even in 1939, the IX-boats achieved useful scores west of Britain.

Stiebler.

05-01-11, 02:18 PM	#4
Stiebler Fuel Supplier Join Date: Oct 2005 Location: London, UK Posts: 1,237 Downloads: 29 Uploads: 4	Ah, the joys of dabbling in statistics! The figures that you quote (8/39 - 8/40; presumably the last days of the month) have little meaning of themselves. Firstly, U-boats were mostly deployed for minelaying around Britain in the first months of the war, and sinkings from mines are probably not counted in Blair's figures. Secondly, many of the U-boats were of the tiny Type II, with very limited range and torpedo capability (and no deck gun). The figures you quote for average patrol times tell their own story: a duration of just 23.6 days is laughably short. Thirdly, U-boats had to surface and stop individual merchant ships according to the prize-rules then extant. This was a slow and dangerous business, especially if enemy aircraft were around. Fourthly, many U-boat torpedoes at this time were hopelessly unreliable, especially if used in shallow waters or high latitudes. Fifthly, Blair's chosen time span includes the German invasion of Norway, when the entire German navy, including all available U-boats, was directed to Norwegian (ie, northern latitude) waters for the purpose of protecting the German invasion fleet from the British Navy. The U-boats found virtually no targets - and when they did fire, their torpedoes were almost all defective. You do not state either your time period, for running up regular totals of 30,000 tons plus, or your U-boat type. But if you had a VIIC or, especially, a IXB boat in late 1940, you could expect to attain a very large score, depending on area. Hessler (U 107) sank nearly 100,000 tons on just one patrol in mid Atlantic during 1941. Even in 1939, the IX-boats achieved useful scores west of Britain. Stiebler. __________________ NYGM Tonnage War Mod - More than a mod: it's an experience!