Fascinating account of actual u-boat patrol

Fidd · 04-14-24, 07:46 PM

It's really interesting to listen to this, and to contrast it with our experience of playing the game. Listen to the narration, then read notes below on technical points. Leaving aside the French "knocking shop", there are a few points worthy of note:

1. When still at some range from the convoy the beats of the massed propellers of the convoy were audible within the u-boat, without using hydrophones. (This also implies that any ship or escort coming over the u-boat should be particularly loud).

2. "There are at least a dozen corvettes along the starboard side". Plainly, due the advent of radar (and Metox) alluded to, this is a 1942 or 1943 battle. However the take-away point is that convoys, at least then, could be MUCH more heavily escorted than we currently experience. I think it likely that this was 2 columns of 6 escorts, likely around a mile apart, on the starboard flank, rather than 12 in line astern.

3. "Convoy at 11 kts". Enough said!

4. (During an air-attack) "The boat fell at a 60 degree angle". Loss of, or difficulty with, vertical control during DC attacks is greatly under-modelled, or is arguably not modelled at all. This should change!

5. "Frederich caught her at 180m"... Another example of partial loss of vertical control, after a crash-dive persued by depth-charges (from an aircraft)?

6. "Verdamant! the fellow has dropped a smoke-bomb and has dyed the sea yellow". (to mark the submergence point of the u-boat). I think we may assume that this was a form of flame-float, as used by the thousand by bombers to ascertain wind-drift for navigation purposes), but with the addition of some form of attached fluourescein type dye. Although the dye was neon in colour, it was not, as far as I'm aware, flourescent at night. The flame-float, designed to burn for about 15 minutes, would provide a small visible illuminated marker for that period.

7. (at 200m) attacked with DC's, suggesting ASDIC could allow targetting to occur at at least that depth. (later when engaged by Hunter Killer Group) "attacked at 265m", again implying ASDIC could locate targets at that depth if no thermocline existed)

8. "patterns of 24 charges hit us at intervals of 20 minutes". Interesting.

9. "over 200 cans had exploded around us". A frightening indication of how sustained DC attacks could be. (45 hours as this account states)

10. "The boat had fallen to 275m". This must have been perilously close to crush depth, even for a type VII/41, which, I suspect, this u-boat must have been).

11. "The water in the bilges rose above the deck-plates". This implies that the battery compartment had a separate unflooded bilge, and that he's talking about a bilge in the forward torpedo room, possibly the control-room, or somewhere aft of the rear battery compartment?

12. Astro-sextant use. Might be an interesting wheeze for navigators, although, from what I know of it, it would have been bloody difficult on a wallowing u-boat, and was mathematically difficult.

13. (of an aircraft dropped "smoke-bomb", [likely a flame-float+dye]) "the thick black smoke" - tells us the colour of the smoke.

14. Sheer number of aircraft attacks. (I lost count). I suspect the losses consequent from attacking these convoys caused the withdrawal of the u-boats from the Atlantic. Likewise surviving a cumulative 500 DC's from escorts plus another 50 or so from aircraft delivered DC's.

Conclusions: This was evidently a severe experience, U230 was very fortunate to survive. Clearly the penalties for getting detected had become exceedingly risky. More applicable to our game, is the integration of air-power frustrating surface-chasing of a convoy, a great increase in the number of escorts, and the very prolonged DC searches/attacks, and, how these persisted even at very considerable depth. Plainly we likely cannot have a viable game at this level of difficulty, but it does indicate, I think, the changes that could be made to some degree, to increase difficulty, and therefore allow experienced crews/players to have scope for play at much greater difficulty. A most necessary aspect to retaining players. Indeed, there could be a system whereby one starts in '39, and only get to advance the date of the next patrol by surviving the previous one. Consequently, there would be some "bragging rights" involved in surviving into 1943...

I'd welcome thoughts on all this.

04-14-24, 07:46 PM	#1
Fidd Captain Join Date: Apr 2005 Location: Blighty! Posts: 494 Downloads: 10 Uploads: 0	Fascinating account of actual u-boat patrol It's really interesting to listen to this, and to contrast it with our experience of playing the game. Listen to the narration, then read notes below on technical points. Leaving aside the French "knocking shop", there are a few points worthy of note: 1. When still at some range from the convoy the beats of the massed propellers of the convoy were audible within the u-boat, without using hydrophones. (This also implies that any ship or escort coming over the u-boat should be particularly loud). 2. "There are at least a dozen corvettes along the starboard side". Plainly, due the advent of radar (and Metox) alluded to, this is a 1942 or 1943 battle. However the take-away point is that convoys, at least then, could be MUCH more heavily escorted than we currently experience. I think it likely that this was 2 columns of 6 escorts, likely around a mile apart, on the starboard flank, rather than 12 in line astern. 3. "Convoy at 11 kts". Enough said! 4. (During an air-attack) "The boat fell at a 60 degree angle". Loss of, or difficulty with, vertical control during DC attacks is greatly under-modelled, or is arguably not modelled at all. This should change! 5. "Frederich caught her at 180m"... Another example of partial loss of vertical control, after a crash-dive persued by depth-charges (from an aircraft)? 6. "Verdamant! the fellow has dropped a smoke-bomb and has dyed the sea yellow". (to mark the submergence point of the u-boat). I think we may assume that this was a form of flame-float, as used by the thousand by bombers to ascertain wind-drift for navigation purposes), but with the addition of some form of attached fluourescein type dye. Although the dye was neon in colour, it was not, as far as I'm aware, flourescent at night. The flame-float, designed to burn for about 15 minutes, would provide a small visible illuminated marker for that period. 7. (at 200m) attacked with DC's, suggesting ASDIC could allow targetting to occur at at least that depth. (later when engaged by Hunter Killer Group) "attacked at 265m", again implying ASDIC could locate targets at that depth if no thermocline existed) 8. "patterns of 24 charges hit us at intervals of 20 minutes". Interesting. 9. "over 200 cans had exploded around us". A frightening indication of how sustained DC attacks could be. (45 hours as this account states) 10. "The boat had fallen to 275m". This must have been perilously close to crush depth, even for a type VII/41, which, I suspect, this u-boat must have been). 11. "The water in the bilges rose above the deck-plates". This implies that the battery compartment had a separate unflooded bilge, and that he's talking about a bilge in the forward torpedo room, possibly the control-room, or somewhere aft of the rear battery compartment? 12. Astro-sextant use. Might be an interesting wheeze for navigators, although, from what I know of it, it would have been bloody difficult on a wallowing u-boat, and was mathematically difficult. 13. (of an aircraft dropped "smoke-bomb", [likely a flame-float+dye]) "the thick black smoke" - tells us the colour of the smoke. 14. Sheer number of aircraft attacks. (I lost count). I suspect the losses consequent from attacking these convoys caused the withdrawal of the u-boats from the Atlantic. Likewise surviving a cumulative 500 DC's from escorts plus another 50 or so from aircraft delivered DC's. Conclusions: This was evidently a severe experience, U230 was very fortunate to survive. Clearly the penalties for getting detected had become exceedingly risky. More applicable to our game, is the integration of air-power frustrating surface-chasing of a convoy, a great increase in the number of escorts, and the very prolonged DC searches/attacks, and, how these persisted even at very considerable depth. Plainly we likely cannot have a viable game at this level of difficulty, but it does indicate, I think, the changes that could be made to some degree, to increase difficulty, and therefore allow experienced crews/players to have scope for play at much greater difficulty. A most necessary aspect to retaining players. Indeed, there could be a system whereby one starts in '39, and only get to advance the date of the next patrol by surviving the previous one. Consequently, there would be some "bragging rights" involved in surviving into 1943... I'd welcome thoughts on all this.