Consequences of the British focusing on winning the Battle of the Atlantic first?

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IOTL the British put the demands of Bomber Command first, letting the Uboats be effective for significantly longer than necessary, potentially delaying victory in the Atlantic by at least 9 months. Supposing that Coastal Command got priority over Bomber command in 1941-42, who much sooner could the BotA have been won and what would the consequences of that decision be, both positive and negative? What resources could then have been shifted to Bomber Command after the Atlantic was secured?
 
IOTL the British put the demands of Bomber Command first, letting the Uboats be effective for significantly longer than necessary, potentially delaying victory in the Atlantic by at least 9 months. Supposing that Coastal Command got priority over Bomber command in 1941-42, who much sooner could the BotA have been won and what would the consequences of that decision be, both positive and negative? What resources could then have been shifted to Bomber Command after the Atlantic was secured?

VLR aircraft are only part of the story.

There are two other major factors: ULTRA and CVEs.

OTL, the British cracked Germany Navy ULTRA (the HYDRA key) in mid-1941, pretty much ending the First Happy Time. (Though only as far as shipping losses were concerned - there were still relatively few U-boats sunk.) This was because by reading German traffic, the Admiralty knew where U-boat scouting lines were deployed, and could just steer around them: "playing blind-man's-bluff with their eyes open", in one historian's phrase.

Then in 1942, at the start of PAUKENSCHLAG, the Germans switched the U-boats to the new TRITON key, which was secure until November. (Broken only with the lucky capture of Enigma material from foundering U-559 off Egypt, and the genius of Alan Turing.) The intervening 10 months were the Second Happy Time.

This time, the break had two effects - it again allowed the Allied convoys to evade contact, and it also provided opportunities for Allied ASW forces to ambush U-boats (while crossing Biscay, for instance, or rendezvousing with a milchkuh). The temporary loss of TRITON in March 1943 threatened a renewed Happy Time, but the codebreakers cracked TRITON again, for good, in less than a month.

None of that would be affected by extra VLR aircraft.

Nor (ISTM) would the deployment of CVEs, which were not built in large numbers until 1942 and didn't reach the Atlantic till mid-1943. The first "mass-production" CVE, USS Copahee, was commissioned 12 June (and was sent to the PTO as an aircraft ferry, as were the second, USS Nassau, and third, USS Altamaha). Only six 1942 CVEs went to the Atlantic, and four of those were commissioned in November and December.

Additional VLR aircraft would have been quite valuable in the Atlantic, more valuable than bombing Germany at the time (or patrolling empty areas of the Pacific, where King sent quite a few). They could have reduced Allied shipping losses in mid-1941 to mid-1943 by about 2M tons, maybe 3M, from OTL 11M tons.

But I don't think one can say they would have "won the Battle of the Atlantic" a lot sooner. The BoA was "won" as of May 1943, when for the first time, U-boat losses were more than half of Allied ships sunk, which was true for the rest of the war (except September and November 1943).

That victory was a combination of ULTRA, CVEs, and VLR aircraft.
 
VLR aircraft are only part of the story.

There are two other major factors: ULTRA and CVEs.

OTL, the British cracked Germany Navy ULTRA (the HYDRA key) in mid-1941, pretty much ending the First Happy Time. (Though only as far as shipping losses were concerned - there were still relatively few U-boats sunk.) This was because by reading German traffic, the Admiralty knew where U-boat scouting lines were deployed, and could just steer around them: "playing blind-man's-bluff with their eyes open", in one historian's phrase.

Then in 1942, at the start of PAUKENSCHLAG, the Germans switched the U-boats to the new TRITON key, which was secure until November. (Broken only with the lucky capture of Enigma material from foundering U-559 off Egypt, and the genius of Alan Turing.) The intervening 10 months were the Second Happy Time.

This time, the break had two effects - it again allowed the Allied convoys to evade contact, and it also provided opportunities for Allied ASW forces to ambush U-boats (while crossing Biscay, for instance, or rendezvousing with a milchkuh). The temporary loss of TRITON in March 1943 threatened a renewed Happy Time, but the codebreakers cracked TRITON again, for good, in less than a month.

None of that would be affected by extra VLR aircraft.

Nor (ISTM) would the deployment of CVEs, which were not built in large numbers until 1942 and didn't reach the Atlantic till mid-1943. The first "mass-production" CVE, USS Copahee, was commissioned 12 June (and was sent to the PTO as an aircraft ferry, as were the second, USS Nassau, and third, USS Altamaha). Only six 1942 CVEs went to the Atlantic, and four of those were commissioned in November and December.

Additional VLR aircraft would have been quite valuable in the Atlantic, more valuable than bombing Germany at the time (or patrolling empty areas of the Pacific, where King sent quite a few). They could have reduced Allied shipping losses in mid-1941 to mid-1943 by about 2M tons, maybe 3M, from OTL 11M tons.

But I don't think one can say they would have "won the Battle of the Atlantic" a lot sooner. The BoA was "won" as of May 1943, when for the first time, U-boat losses were more than half of Allied ships sunk, which was true for the rest of the war (except September and November 1943).

That victory was a combination of ULTRA, CVEs, and VLR aircraft.

You can make an argument that the Battle of the Atlantic was won in July 1942. That's the first month that merchant ship production outstripped sinkings (in terms of tonnage) and that trend continued for the rest of the war.
 
You can make an argument that the Battle of the Atlantic was won in July 1942. That's the first month that merchant ship production outstripped sinkings (in terms of tonnage) and that trend continued for the rest of the war.

This graph shows two key stats for the Battle of the Atlantic.
Uboatwar graph.jpg

(Data from the appendix to 20,000,000 Tons Under the Sea by RAdm Dan Gallery, the man who captured U-505.

The blue line is the ratio of merchant ships sunk to U-Boats lost each month; the red line is the number of U-boats in service (x10 the number at right to scale it - this was done with primitive tools). The vertical line is May 1943. It marks a clear division between two phases of the BoA. After that time, U-boat strength declines continuously, and the loss ratio is very low and stays low.

Before that - there's the opening phase, with few U-Boats and fairly low loss ratio. Then a long period of high loss ratio and growing U-boat strength. During this period the Germans are winning. Then in July 1942, the Allies made some changes to ASW tactics (in part driven by the findings of operations research). U-boat strength plateaued around 400, and the loss ratio dropped a lot (due mainly to much increased U-boat losses - the shipping losses remained horrible). This 10-month period could be described as "even battle", which in May 1943 broke decisively for the Allies.

I would say that this definitely shows May 1943 as the point when the BoA had been decided.
 
Here's a better graphic.
U-boat.jpg

Blue: U-boats in service
Purple: U-boats sunk
Green: Allied ships sunk
Brown: ships/U-boats ratio (filled in with 200 for months with no U-boats lost).

The left dotted line is July 1942; the right dotted line is May 1943.

This graph, perhaps even better than the other one, shows how the Germans were winning until mid-1942. Then for ten months it was a "see-saw" battle (with both sides trying to build faster than their losses). Then the Allies win.

It also shows that while ULTRA was extremely important, it was not decisive. The comparative respite of late 1941 is visible - but the situation was still very grim. The drop in sinkings at the end of 1942 (when Turing cracked TRITON) is visible - but so is the rebound in March 1943, when TRITON went dark again. The great change was when ULTRA, CVEs, and VLR aircraft were all on-line.
 
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You can make an argument that the Battle of the Atlantic was won in July 1942. That's the first month that merchant ship production outstripped sinkings (in terms of tonnage) and that trend continued for the rest of the war.

And another argument can be made that the Battle of the Atlantic was won in the fall of 1941.

This was the first time period that German U boats losses against properly (key term) escorted convoys in the north Atlantic became unsustainable given the number of allied ships sunk. The good news for the Germans is that there were still plenty of improperly escorted convoys, especially in US coastal waters ("Second Happy Time"), the Indian Ocean and to a lesser degree, the south Atlantic. The bad news was that the allies were steadily gaining the capacity to ensure that every convoy, even in the secondary zones, was properly escorted.
 
Shifting more aircraft to the CC does not solve some of other issues:
- availablity of the Azores
- availablity of escort carriers and their aircraft complements
- American dropping the ball in winter of 1941/42
- availability of electronics needed to outfit the aircraft

Plus - Hampdens, Blenheims and Wellingtons were not as rangy as B-24s.

Further, giving the Germany the respite from, innefective as they were, bombing raids in 1941-42 means Germany invests less on the air defence (cannons, ammo, electronics, manpower, decoys/spoofs) in these years. Mening Heer artillery and other units are better outfitted for 1942-43, there is enough of radars for aircraft and radios overall, and industry has a willing manpower thus less dependance on slave labour.
Also - how the Altlantic startegy influences the introduction of electronics and training for the Bomber Command vs. ground targets?
 
Shifting more aircraft to the CC does not solve some of other issues:
- availablity of the Azores
- availablity of escort carriers and their aircraft complements
- American dropping the ball in winter of 1941/42
- availability of electronics needed to outfit the aircraft

Plus - Hampdens, Blenheims and Wellingtons were not as rangy as B-24s.

Further, giving the Germany the respite from, innefective as they were, bombing raids in 1941-42 means Germany invests less on the air defence (cannons, ammo, electronics, manpower, decoys/spoofs) in these years. Mening Heer artillery and other units are better outfitted for 1942-43, there is enough of radars for aircraft and radios overall, and industry has a willing manpower thus less dependance on slave labour.
Also - how the Altlantic startegy influences the introduction of electronics and training for the Bomber Command vs. ground targets?

I thought the effort the British poured into bombing far outweighed the effort the Germans spent on defending against the bombers?

IOTL the British put the demands of Bomber Command first, letting the Uboats be effective for significantly longer than necessary, potentially delaying victory in the Atlantic by at least 9 months. Supposing that Coastal Command got priority over Bomber command in 1941-42, who much sooner could the BotA have been won and what would the consequences of that decision be, both positive and negative? What resources could then have been shifted to Bomber Command after the Atlantic was secured?

The thing is, coastal command can't absorb 80% of British GDP the way bomber command did - so even when you pump Coastal Command up to the max, there's still going to be plenty left over - if Britain has some spare shipyard space, some escort carriers would be the perfect thing. Even those two combined would still leave plenty of productive capacity and manpower for bomber command or other more aggressive investments. I suspect that if CC only were pumped to the max and BC got what remained, BC would be infinitesimally smaller and the stronger CC would reduce the shipping losses, but on its own wouldn't radically reduce losses.

fasquardon
 
We could see D day six months earlier.Germany is screwed then Japan is screwed.
I totally agree. The Atlantic was the one place the US and GB could have lost the war. It also would have allowed increases in supplies to the Soviet Union. One thing to remember subtracting a couple hundred long range bombers would not have significantly impacted continental bombing. Slightly smaller numbers.
 

There's been a lot of debate about this but I think the modern consensus is it was relatively effective. I'll have to dig around for the source later, but one of the consequences of the strategic bombing campaign was that, as of 1943, 41% of German war production was devoted to producing aircraft - the largest single part of the German war economy by a significant margin. By comparison, tanks were only about 6% of German war production during that period. By the start of 1944, more than half the Luftwaffe was deployed at home airfields for the Defense of the Reich, which was also a huge diversion of resources from the Eastern Front.

If Coastal Command were to take away a substantial portion of Bomber Command's resources early in the campaign then it seems conceivable that gains made in the Atlantic might be cancelled out by increased German strength in the Eastern Front. This of course depends on how much longer it would really take Bomber Command to scale up operations - IIRC, one of Harris' major points of contention with Coastal was that he wanted every plane available to put together the first 1,000-bomber raid, which Coastal refused to do - and what German planners' threshold for response really was. Could the Luftwaffe have been pinned in place by less intensive raids? Would German war production have focused meaningfully less heavily on aircraft without the need to defend against so many bomber streams?

We could see D day six months earlier.Germany is screwed then Japan is screwed.

Was D-Day even feasible in the middle of winter?
 
...

Was D-Day even feasible in the middle of winter?

Depends on what 'DDay' is. Detailed plans a Brit staff laid out in mid 1942, saw landings on the east coast of the Cotintin practical into October. That coast is sheltered from the more common westerly storms from the Atlantic. Since the plan did not see Cherbourg captured rapidly I have to assume the staff expected cross beach supply into November.

Beyond that I'd think a operation the size of Op HUSKY would be practical a year earlier in mid 1943.
 
Here's a better graphic.
View attachment 319136
Blue: U-boats in service
Purple: U-boats sunk
Green: Allied ships sunk
Brown: ships/U-boats ratio (filled in with 200 for months with no U-boats lost).

The left dotted line is July 1942; the right dotted line is May 1943.

This graph, perhaps even better than the other one, shows how the Germans were winning until mid-1942. Then for ten months it was a "see-saw" battle (with both sides trying to build faster than their losses). Then the Allies win.

It also shows that while ULTRA was extremely important, it was not decisive. The comparative respite of late 1941 is visible - but the situation was still very grim. The drop in sinkings at the end of 1942 (when Turing cracked TRITON) is visible - but so is the rebound in March 1943, when TRITON went dark again. The great change was when ULTRA, CVEs, and VLR aircraft were all on-line.

A item not mentioned in connection to these graphs is the penetration of the convoy codes by the Germans. I don't have the exact dates at hand, but the ability of the submarine packs to intercept the convoys mid Atlantic connected to the ability to read the messages using that code. When the Brits closed that breech the interception of the convoys dropped significantly. A close look at the number of interceptions enabled by the breech of the convoy code may suggest another direction for winning the BoA sooner.
 
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The thing is, coastal command can't absorb 80% of British GDP the way bomber command did

It wasnt anything near 80% of GDP its hard to be exact but a reasonable figure was approximately 6% of GDP and 10% of the war budget. The Royal Navy accounted for about 40% of the war budget, the RAF about 30% the Army about 25% and the balance was aid to the Soviet Union. Britain spent more on importing Tobaco than it did on Bomber Command.
 
There's been a lot of debate about this but I think the modern consensus is it was relatively effective. I'll have to dig around for the source later, but one of the consequences of the strategic bombing campaign was that, as of 1943, 41% of German war production was devoted to producing aircraft - the largest single part of the German war economy by a significant margin. By comparison, tanks were only about 6% of German war production during that period. By the start of 1944, more than half the Luftwaffe was deployed at home airfields for the Defense of the Reich, which was also a huge diversion of resources from the Eastern Front.

If Coastal Command were to take away a substantial portion of Bomber Command's resources early in the campaign then it seems conceivable that gains made in the Atlantic might be cancelled out by increased German strength in the Eastern Front. This of course depends on how much longer it would really take Bomber Command to scale up operations - IIRC, one of Harris' major points of contention with Coastal was that he wanted every plane available to put together the first 1,000-bomber raid, which Coastal refused to do - and what German planners' threshold for response really was. Could the Luftwaffe have been pinned in place by less intensive raids? Would German war production have focused meaningfully less heavily on aircraft without the need to defend against so many bomber streams?



Was D-Day even feasible in the middle of winter?

I totally agree WRT the bomber offensive turning into a giant resource suck for the Germans but in this case people are not talking bleeding Bomber Command or what would become the US 8th Air Force in favor of Coastal Command and its US equivalent units. Correct me if I am wrong but people are talking about is a few dozen bombers.
 
There was no single factor that could win the Battle of the Atlantic significantly early
but there were a number of very feasible changes the RN can make that together would have made great impact

All were eventually discovered or invented and implemented but all could - no should .. have been recognized earlier.:

  • The Atlantic is BIG and parts are far away
    so the aircraft you can use off the coast are not the same as needed for convoy support
    You need an Atlantic Command

  • For the forseeable future Convoys are the only place to do ASW
    so forget area and interdicion (even the Bay of Biscay from late '40)

  • bigger convoys are more efficiently defended (4x ships only has 2 xPerimeter)
    so accept the crowding at ports

  • the best setting for an air dropped depth charge is NOT the one for an average UB
    but the one that has most kills (a result of non linear effect a
    so create a 25' setting (and ensure it works)

  • ASW aircraft need a means of attacking a sub on the surface
    so develop Rocket Projects or fit a suitable gun in the nose (as was originally speced for the Sunderland)

  • even minimal organic Air support greatly strengthens a convoys defence
    so initiate a program to build MAC ships in paralle to or even before CVEs rather than afterwards

  • LR ASW aircraft are extremely cost effective even in small numbers
    so use your less effective heavy bombers in that role (and yes Mr Stirling I'm looking at you)

  • Conversely Strategic Bombing needs numbers to be effective
    so a small delay in your planned growth is acceptable

  • This is a Campaign not a battle, but fortunately attrition in the air is (relatively low)
    In fact just setting the weather standards for aborting a bomber raid a bit higher
    will reduce losed allow a strong Atlantic Command.

  • VLR ASW are more precious than gold
    so use EVERY B-24 for that role, even persuading the manufacturers to build them that way

  • a "throw ahead" ASW weapon allows ASDIC contact to be maintained
    so look into Squid
  • most of your ASW ships are small and already crowed so look at a lighter throw ahead weapon
    i.e Hedgegog

  • ASW is difficult
    so train for it. Select and Promote those with the knack

  • 2 ASW Platforms are more than twice as effective as 1
    so setup teams ... and keep the teams together (air and surface)
Even with all its other commitments the UK can do all these by and of itself from mid '39.
As others have said by OTL Mid 1941 the position was already nearly sustainable.
With the above in place it would be much better in ATL.

Now if the RN could only persuade the USN to do the same then the Second happy time would be avoided
and by mid '42 the situation would be a clear win.
 
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Depends on what 'DDay' is. Detailed plans a Brit staff laid out in mid 1942, saw landings on the east coast of the Cotintin practical into October. That coast is sheltered from the more common westerly storms from the Atlantic. Since the plan did not see Cherbourg captured rapidly I have to assume the staff expected cross beach supply into November.

Beyond that I'd think a operation the size of Op HUSKY would be practical a year earlier in mid 1943.
Weren't the mid-1942 plans made in case a Russian collapse looked imminent and only for use in such an emergency? The Dieppe raid (Operation Jubilee) was in 1942 and demonstrated just how badly wrong an Allied landing in France could go at that time...
 

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We could see D day six months earlier.Germany is screwed then Japan is screwed.
Can't see why or how.

The number of amphibious assets won't be any more ready. The number of troops won't be any more ready. Most critically the WAllies won't have air supremacy. If anything it will take longer to establish air supremacy because there will have been less winnowing of the Luftwaffe.
 
VLR Liberators which were capable of covering the black gap were available in numbers from late 41 - when 1 single Squadron...I repeat...1 single squadron was made available to coastal command and those VLR Liberators available to the USN where based everywhere but the Atlantic and no more were provided until March 43 when 50 more where 'grudgingly' provided after merchant losses began to spiral up and had an immediate impact.

They and other aircraft being made available made any attempt by U-boats to cross the Bay of Biscay a suicide mission.

Now I do appreciate that the ultimate Victory in May 43 was a culmination of multiple assets, doctrines and technologies (not to mention improved training and experience over 3 years of war) - Alanjwhites post#17 goes into detail (I would add improving the Convoy codes to your list) but in 1940 and 1941 a very modest increase in the number of bombers would have had a massive detrimental impact on the u-boats ability to operate in the seas around the UK - where they were at the time operating.

Indeed it was a relatively low number of land based aircraft that forced them away from the British Isles and into the black gap OTL in the first place.

Significantly increase this number and the u boats will be far less able to operate on the surface in day time.

Its not uboat kills that won the battle - it was preventing the uboats from being able to sink Merchantmen that won the battle - sinking them was just a bonus.
 
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