Can’t find the thread Blutarski started some time ago so had to restart.
An attack in Flanders was in Haig’s mind at least by 17 Jun 17 when he met Admiral Bacon at Dover Castle and recorded in his diary that Bacon was “wholeheartedly with us and has urged in writing to the Admiralty the absolute necessity of clearing the Belgian coast before winter”.
Whether Haig saw clearing the coast as the main potential gain or just as another argument in favour of his preferred course I know not but that doesn’t really matter. The immediate question is “Why Ypres for the decision makers at the time?” not “Was Ypres a good idea in hindsight?”
There seem to be two sides to the effects achieved by the U boats in Flanders and how they influenced the decision to attack at Ypres rather than somewhere else in the British sector: material and mental.
Material
I’ve just got War Beneath the Waves by Tomas Termote from which I’ve extracted some figures:
Patrols per month, early 18, by U boats based in Germany, Flanders, Med:
27 / 20 / 12
U boats based in Germany, Flanders, Med in this period:
54 / 24 / 35
Patrols per U boat based in Germany, Flanders, Med:
0.5 / 0.833 / 0.34
Tonnages sunk by U boats based in Germany, Flanders, Med: (by 01 May 18)
4,219,000 / 2,501,000 / 2,480,000
U boats based in Germany, Flanders, Med in this period:
55 / 22 / 31
Tonnages sunk per U boat based in Germany, Flanders, Med in this period:
76,709 / 113,682 / 80,000
Losses of U boats based in Germany, Flanders:
14%, 13% (“during their respective operations” - the Flanders bases were evacuated before the end of the war so the North Sea based boats faced late war Allied ASW a bit longer).
Mental
The British leadership had no idea what they could do at sea to reduce the losses to a sustainable level before convoy was introduced.
Losses in 1917 got close to 25% of all long distance sailings. Not a typo that, a quarter, much, much worse than in WWII.
From Torpedo Terror by Richard Freeman and Convoy by John Winton.
Q ships had passed a peak of effectiveness with the Germans now assuming merchant ships were hostile, as had arming real merchant ships for the same reason.
800 merchant ships out of 3,600 had been armed by Aud 17 with more coming at 37 ships a day.
The last U boat sinking by a Q ship was in Sep 17., by then over 70 actions had been fought by Q ships,sinking 14 U boats for the loss of 27 Q ships.
Depth charges were proving effective but in short supply and, much more important, the times when AS ships knew where to drop them were limited to just after a visual sighting.
Hydrophones could work but gave very variable results.
(USN Sub Chasers detected a U boat 150 miles off of Land’s End and ran out of depth charges without sinking it. They could hear sounds they interpreted as the boat trying to get free from grounding as they waited for two SCs to get to and back from Plymouth with more charges. After a salvo of these fresh charges they heard pistol shots from below.
OTOH two destroyers and twelve SCs spent two and a half hours plus chasing U-53 to no avail. Both incidents in early Sep 17).
The Dover Barrage could work, but not until Keytes took over and changed the way it operated, helped by the U boat command falsely attributing three losses in quick succession to it.
AS patrols did work but not as well as hoped. In combination with other techniques late in the war they made operating in some waters a tremendous strain on the U boat crews.
(Aside - CP opinion, their main effect was to force U boats to submerge; air patrols did that as well as surface ones but could cover much greater areas).
Convoy was not introduced until about May 17 and then gradually though quite quickly. Freeman casts Jellicoe as the major problem, determined not to permit convoys, Winton presents him less negatively but as depressed by the defeat he could see coming and could not see how to prevent. Both note that Beatty was an early and forceful advocate of convoys, though he could only express an opinion, he was not part of the decision making group. Still a very senior officer's opinion but.
Losses declined after convoy was introduced but were still serious in Sep 17, it seems to be in that month that a sharp change in the lossrate happened.
Some timings:
Dec 16: Lloyd-fg-George engineers Asquith’s resignation and his own promotion. Soon followed by a wave of new appointments, who would have had or been looking for new ideas. Some had to justify their recent promotions.
01 Feb 17 Germany adopts USW.
Mar 17 losses were 10% up (594,000 tons) A quarter of inbound shipping. (RF)
31 Mar 17 Rear Admiral Sims, USN, arrives in London, briefed by Jellicor (FSL) with the real loss figures.
Jellicoe - “It is impossible for us to go on with the war if losses like this continue.”
Sims - “Is there no solution to this problem?”
Jellicoe - “Absolutely none that we can now see.”
(Both Freeman and Winton)
May taken by Freeman as the beginning of convoy, it wasn’t a step change.
Average monthly sinkings May Aug: 588,000 tons. (Doesn’t agree with figures given, I get 349,500)
Jan to Jun 17: 2.1 million tons of British losses, 3.7 million tons worldwide.
31 Jul 17 Attack at Pilkhelm Ridge opens 3rd Ypres.
At a War Cabinet meeting on 17 Sep 17 Wemys, for the Admiralty, forecast losses for the month at 270,000 tons, Geddes, a civilian, was more pessimistic as fewer U boats had been sunk. I think Wemyss’ figure suggests early Sep looked as bad as ever, in turn late Sep was a huge drop, greater than the 34% month to month.
Quite a few contradictory figures in Freeman, I suspect some of them are UK and some world. You don’t notice them buried in the text of a well told yarn.
It seems clear that British leaders had come to the same conclusion as German ones, attacking British merchant shipping could win the war for Germany.
The figures for patrols and tonnages per U boat suggest that clearing the Belgian ports would reduce the U boats’ effectiveness markedly.
Whether by enough and whether possible are further questions but given attacking was required and that (my guess) multiple small attacks were judged not enough to maintain civilian morale a big attack somewhere that didn’t have any chance of reducing the U boats’ effects would have to have something else very attractive about it to be chosen.
Aside - The introduction of convoy coincided with Room 40 beginning to reliably track U boats by DF. Over the same few months Depth Charge production and issue came on stream, the USN invented DC rack allowed more effective patterms, USN forces increased the total ASW fleet considerably, Keyes made the Dover Barrage far more effective and the USN started to lay the Northern Barrage.
Convoy was key and would have helped a great deal earlier, but it wasn't the sole factor by a long way.
An attack in Flanders was in Haig’s mind at least by 17 Jun 17 when he met Admiral Bacon at Dover Castle and recorded in his diary that Bacon was “wholeheartedly with us and has urged in writing to the Admiralty the absolute necessity of clearing the Belgian coast before winter”.
Whether Haig saw clearing the coast as the main potential gain or just as another argument in favour of his preferred course I know not but that doesn’t really matter. The immediate question is “Why Ypres for the decision makers at the time?” not “Was Ypres a good idea in hindsight?”
There seem to be two sides to the effects achieved by the U boats in Flanders and how they influenced the decision to attack at Ypres rather than somewhere else in the British sector: material and mental.
Material
I’ve just got War Beneath the Waves by Tomas Termote from which I’ve extracted some figures:
Patrols per month, early 18, by U boats based in Germany, Flanders, Med:
27 / 20 / 12
U boats based in Germany, Flanders, Med in this period:
54 / 24 / 35
Patrols per U boat based in Germany, Flanders, Med:
0.5 / 0.833 / 0.34
Tonnages sunk by U boats based in Germany, Flanders, Med: (by 01 May 18)
4,219,000 / 2,501,000 / 2,480,000
U boats based in Germany, Flanders, Med in this period:
55 / 22 / 31
Tonnages sunk per U boat based in Germany, Flanders, Med in this period:
76,709 / 113,682 / 80,000
Losses of U boats based in Germany, Flanders:
14%, 13% (“during their respective operations” - the Flanders bases were evacuated before the end of the war so the North Sea based boats faced late war Allied ASW a bit longer).
Mental
The British leadership had no idea what they could do at sea to reduce the losses to a sustainable level before convoy was introduced.
Losses in 1917 got close to 25% of all long distance sailings. Not a typo that, a quarter, much, much worse than in WWII.
From Torpedo Terror by Richard Freeman and Convoy by John Winton.
Q ships had passed a peak of effectiveness with the Germans now assuming merchant ships were hostile, as had arming real merchant ships for the same reason.
800 merchant ships out of 3,600 had been armed by Aud 17 with more coming at 37 ships a day.
The last U boat sinking by a Q ship was in Sep 17., by then over 70 actions had been fought by Q ships,sinking 14 U boats for the loss of 27 Q ships.
Depth charges were proving effective but in short supply and, much more important, the times when AS ships knew where to drop them were limited to just after a visual sighting.
Hydrophones could work but gave very variable results.
(USN Sub Chasers detected a U boat 150 miles off of Land’s End and ran out of depth charges without sinking it. They could hear sounds they interpreted as the boat trying to get free from grounding as they waited for two SCs to get to and back from Plymouth with more charges. After a salvo of these fresh charges they heard pistol shots from below.
OTOH two destroyers and twelve SCs spent two and a half hours plus chasing U-53 to no avail. Both incidents in early Sep 17).
The Dover Barrage could work, but not until Keytes took over and changed the way it operated, helped by the U boat command falsely attributing three losses in quick succession to it.
AS patrols did work but not as well as hoped. In combination with other techniques late in the war they made operating in some waters a tremendous strain on the U boat crews.
(Aside - CP opinion, their main effect was to force U boats to submerge; air patrols did that as well as surface ones but could cover much greater areas).
Convoy was not introduced until about May 17 and then gradually though quite quickly. Freeman casts Jellicoe as the major problem, determined not to permit convoys, Winton presents him less negatively but as depressed by the defeat he could see coming and could not see how to prevent. Both note that Beatty was an early and forceful advocate of convoys, though he could only express an opinion, he was not part of the decision making group. Still a very senior officer's opinion but.
Losses declined after convoy was introduced but were still serious in Sep 17, it seems to be in that month that a sharp change in the lossrate happened.
Some timings:
Dec 16: Lloyd-fg-George engineers Asquith’s resignation and his own promotion. Soon followed by a wave of new appointments, who would have had or been looking for new ideas. Some had to justify their recent promotions.
01 Feb 17 Germany adopts USW.
Mar 17 losses were 10% up (594,000 tons) A quarter of inbound shipping. (RF)
31 Mar 17 Rear Admiral Sims, USN, arrives in London, briefed by Jellicor (FSL) with the real loss figures.
Jellicoe - “It is impossible for us to go on with the war if losses like this continue.”
Sims - “Is there no solution to this problem?”
Jellicoe - “Absolutely none that we can now see.”
(Both Freeman and Winton)
May taken by Freeman as the beginning of convoy, it wasn’t a step change.
Average monthly sinkings May Aug: 588,000 tons. (Doesn’t agree with figures given, I get 349,500)
Jan to Jun 17: 2.1 million tons of British losses, 3.7 million tons worldwide.
31 Jul 17 Attack at Pilkhelm Ridge opens 3rd Ypres.
At a War Cabinet meeting on 17 Sep 17 Wemys, for the Admiralty, forecast losses for the month at 270,000 tons, Geddes, a civilian, was more pessimistic as fewer U boats had been sunk. I think Wemyss’ figure suggests early Sep looked as bad as ever, in turn late Sep was a huge drop, greater than the 34% month to month.
Quite a few contradictory figures in Freeman, I suspect some of them are UK and some world. You don’t notice them buried in the text of a well told yarn.
It seems clear that British leaders had come to the same conclusion as German ones, attacking British merchant shipping could win the war for Germany.
The figures for patrols and tonnages per U boat suggest that clearing the Belgian ports would reduce the U boats’ effectiveness markedly.
Whether by enough and whether possible are further questions but given attacking was required and that (my guess) multiple small attacks were judged not enough to maintain civilian morale a big attack somewhere that didn’t have any chance of reducing the U boats’ effects would have to have something else very attractive about it to be chosen.
Aside - The introduction of convoy coincided with Room 40 beginning to reliably track U boats by DF. Over the same few months Depth Charge production and issue came on stream, the USN invented DC rack allowed more effective patterms, USN forces increased the total ASW fleet considerably, Keyes made the Dover Barrage far more effective and the USN started to lay the Northern Barrage.
Convoy was key and would have helped a great deal earlier, but it wasn't the sole factor by a long way.
statistics: Posted by ChrisPat — 1:02 AM - Today — Replies 2 — Views 63