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AS · 12-14-06, 02:48 PM

Sorry to say so, but you are WRONG if you compare the VIIb depth (90m) to that of a U.S. Sub. The reason is quite simple: The German Navy calculated a safety-factor of 2.5 for their "operational depth", while the U.S Navy calculated with approx. 1.5. This means:

Type VII U-Boat: 100m "safe" operational depth, multiplied by the factor 2.5 = 250m assumed maximum depth close to crash depth (today we know that the crash depth assumption were too pessimistic in those days, as you all know, U-Boats could go a bit deeper than 250m)

US-Sub: 90m (later 120m) operational depth, multiplied by 1.5 = 135 (respectively 180m) maximum depth near crash depth.

So, U.S. subs couldn´t go very deep, but they were not meant to, either, because in the Pacific both crash dive time (VIIc: 25sec., US Gato: 50sec.) and maximum depth didn´t play such an important role, whereas long range travelling, a huge torpedoe load-out and comparatively comfy crew accomodations were much more important for the Pacific theatre.

My two cents, AS

12-14-06, 02:48 PM	#9
AS 中国水兵 Join Date: Jan 2004 Location: Germany Posts: 275 Downloads: 135 Uploads: 0	Sorry to say so, but you are WRONG if you compare the VIIb depth (90m) to that of a U.S. Sub. The reason is quite simple: The German Navy calculated a safety-factor of 2.5 for their "operational depth", while the U.S Navy calculated with approx. 1.5. This means: Type VII U-Boat: 100m "safe" operational depth, multiplied by the factor 2.5 = 250m assumed maximum depth close to crash depth (today we know that the crash depth assumption were too pessimistic in those days, as you all know, U-Boats could go a bit deeper than 250m) US-Sub: 90m (later 120m) operational depth, multiplied by 1.5 = 135 (respectively 180m) maximum depth near crash depth. So, U.S. subs couldn´t go very deep, but they were not meant to, either, because in the Pacific both crash dive time (VIIc: 25sec., US Gato: 50sec.) and maximum depth didn´t play such an important role, whereas long range travelling, a huge torpedoe load-out and comparatively comfy crew accomodations were much more important for the Pacific theatre. My two cents, AS __________________ Whenever people agree with me I always feel I must be wrong. (Oscar Wilde)