German unrestricted submarine warfare in WW1.

[Mikestone8]

IIRC wasn't that the practice during 1916? I mean in USW against clearly armed merchant ships.

It was certainly the practice of some U-boat captains. See my remarks on the Marina and Arabia. But as I understand matters it wasn't official policy.

 

[Mikestone8]

The submarines of the time were not like those of WW2, they were basically a mobile minefield, in reality they relied greatly on someone coming to them rather than them going to their targets as they were too slow and short ranged

Not as short-ranged as all that. U-53 caused a stir in mid-1916 by sinking several vessels off New England, just outside the US 3-mile limit.

The main limitation on u-boats' time at sea was their need to return to Germany (running the gauntlet of British minefields in the North Sea and Channel) when they ran out of torpedoes.

 

[BlondieBC]

There are a lot of misconceptions here, often due to deliberate misinformation campaign by the RN between the wars and the various politically motivate statements of politicians. You are entitled to your opinion, but not your own facts. So let us go over some important basic information you guys should remember on this topic. These are FACTS. I keep bringing these up every few months, but some people just ignore them.

Here is the book that compiles the information.

Selected Sources from the British
National Archives, Kew
Edited by Hans Joachim Koerver

Facts

1) Germany always used USW rules in some locations. It never sank all the ships without warning. Don't mistake the declarations of USW done largely for diplomatic gains (to keep ships from even trying to sail to Entente ports) from actual ROE given to captains.

1A) There were locations that ALWAYS had USW rules for the ENTIRE WAR. Once you turned north from Crete, the Germans would sink everything.

1B) There were always inspect areas, since you would not want to sink say a blockade runner going to an Ottoman port. Or a German port. Or at times to a Dutch or Norweign port.

2) Declaration of USW did not necessarily mean that the % sunk without warning increased. For example in 1915 in North Sea and Atlantic, without USW the Germans open the year with 70% then 94% sunk without warning. Then we do a declaration of USW and we get 44/39/61/36/11/20/31. Or put another way, in the 1915 declared USW, the were closer to following cruiser rules.

3) The change in tonnage sunk is mostly related to number of ships on patrol. The cruiser versus USW rules were of limited impact. It is key to remember this is not WW2. Some key differences.

- It takes 10 to 14 hours for a British Warship to respond, when they responded.
- 1/3 of ships and 1/10 of tonnage are sail powered.
- There are few to no effective weapons against submerge subs. Once a sub went below the water line, it largely was immune to damage. This slowly changes some over the war.
- A high % of these ships don't even have radios.

So the actual risk to German U-boats of applying cruiser rules is limited when one looks at a slow powered merchant ship or sailing ship.

 

[BlondieBC]

The submarines of the time were not like those of WW2, they were basically a mobile minefield, in reality they relied greatly on someone coming to them rather than them going to their targets as they were too slow and short ranged until the really big designs like the U-Cruisers came about.

Cruiser warfare rules does not work, its a lovely idea but it does not work in practice, really the subs only choice was unrestricted warfare.

Not true. While not as good as WW2 subs, the merchant ships were also not as good. Much higher % sail. Slower average speed. Often without radios.

And cruiser rules did work just about as well as USW rules on tonnage sunk. Take the highest USW % months in 1915. Interesting both were in the cruiser rule periods, but have the highest USW period.

Sept 1915 in Med. 100% without warning. 210 tons per patrol day.
Feb 1915 in Atlantic. 94% USW, 778 tons per day.

Now for the high tonnage per ship day.

November in Med. 13% USW, 2,387 tons per patrol day.
September in Atlantic (declared USW period) 31% USW and 2,227 per patrol day.


In 1916, the highest tonnage per day are under cruiser rules. USW falls in the middle of the data.

 

[BlondieBC]

And by your link the damage done to British shipping soared after USW was declared from 325,000 tons a month to over 850,000 by April. Not only that, but the British were forced to go to the convoy system that greatly reduced the capacity of their shipping- convoys move only at the speed of the slowest ship

In any event, it would have been obvious that continued cruiser rule warfare was not going to bring the British down

The German Army in the field peaks in January 1917 The casualties were mounting and the Russian revolution relieves a huge amount of pressure on not only them but there allies. They had no means to make good their losses against their opponents huge populations and colonial troops.

The Germans knew they were looking at defeat (the Turks were already seeking terms), the Austrains were worn out. The collapse of the Russian war effort is what lets Germany get through 1917 and the release of German and Austrian POWs is what lets them get through 1918

Your really need to look at the data instead of speculating. The biggests difference from Oct 1916 to January 1917 compared to the next 4 months is number of ships on patrol on average day. It jumps from 15/13/13/17 or roughly 14.5 to 23/27/31/29 or 27 and change. Doubling he number of ships is the biggest reason for the increased losses by Entente. And at least this time we do see a real rule change. We have a 7-13% USW % by month jump to 47 to 81% range.

This data is the best data for USW, but we only see sinkage per patrol day jump by 32% from 418 to 552. If I select other date ranges or more of the data, the case becomes weaker. For example, the next 4 months give you 1598 or 400 tons per day which is a 5% loss in effectiveness.

Now we really need to get into some cross correlations and counter measures and changes in USA policies and other factors for the more complete picture, but it is pretty clear USW rules did not make that much a difference. One can argue the actual rule changes did since the USA did not seem to respond to the actual ROE changes but German press releases.

 

[BlondieBC]

Then how would USW do any better?

Since the subs of that era could carry only a limited supply of torpedoes, the vast majority of sinkings still had to be done by gunfire or demolition charge - ie the same way as before USW.

The sensible course would have been to declare USW against armed ships only. Since most Allied vessels were by 1917 either already armed or in process of being, this would have provided more than enough targets to use up all of a sub's torpedoes - but would have avoided destruction without warning of American ships, since none of these were currently armed, and Wilson would almost certainly have swallowed it.

As to why the Garman Admiralty held out for total USW, this may have been just a temperamental dislike of "half measures" plus irritation with a neutral like Wilson continually poking his nose in (note the Kaiser's famous marginal comment). I suspect, however, that they were preparing their excuses in anticipation of defeat, and didn't want anyone saying "We'd have won if USW hadn't been watered down". The irony is that they would most likely have won if only it had been.

I agree with parts here. As to the explanation of USW warfare declaration, I lean towards other factors. It is pretty clear that Germany could change ROE without the world noticing since world reactions did not time with the sinking %. It is clear the Kaiser could be impulsive. We can go with the Germans did not care about the USA or neutral reaction, but there is a simpler explanation that I favor. The declaration was a deliberate effort to intimidate neutral SHIP OWNERS not to sail for the UK and Northern France. IMO, the target was more the large Norweign merchant marine fleet along with other powers such the Dutch. The Germans just miscalculated that the neutrals would not sail, they did in fact sail due to financial pressures such as bankruptcy. The Germans did not account for the large number of neutral merchant ships sitting in USA ports that would also be pressed into service.

As to your proposed ROE, it would have certainly worked. But it is more than needed. Simply modifying the ROE to force use of cruiser rules on passenger liners would have been enough, along with a plan to deny, deny, deny if a Captain made a mistake with a torpedo. Then put in tougher rules. The passenger ships ran on know schedules with know routes and ports. The USA did not object to sinking of ships that were not USA flagged or had USA citizens. It was really the Lusitania that change the American tone, and without the dumb newspaper ads designed to intimidate people, it would have been a deniable mistake even if the captain would have thought it was a non-passenger ship and still sunk it.

 

[BlondieBC]

IIRC wasn't that the practice during 1916? I mean in USW against clearly armed merchant ships.

Yes, and in some locations against unarmed merchant ships. The USA was not defending some abstract moral principle as we like to claim, but we were really complaining about loss of USA lives and/or USA property. We cared less how many Brits/Aussies/Egyptians/whatever died in a ship running food or other supplies to Greece.

 

[BlondieBC]

The Germans didn't know that the Bolsheviks were going to take power and sue for peace when they launched their USW. The Febuary Revolution does bring the grossly inept Kerensky regime that allows them to survive 1917

Yes, the Germans made a horrid mistake in pursuing USW. They made many others as well. It was a war losing move

But if the question is "why did they do it?" The answer is that they perceived their position as dire and getting worse. Continuing the restricted Submarine warfare wasn't doing anywhere near enough damage to Britain and the Germans knew it

Would they have done better by not going to USW? Probably not, They are likely to lose the war in either case

Germans win WW1 without USW. Easy TL. Whites still take power about on time. Russia probably leaves war earlier since Whites probably make peace, but let us say they don't make peace. Blockade is lot looser without USA support. UK runs out of money in early 1917 for imports, so supplies go down 25% to 35%. France is running low on manpower by 1918. France will be knocked out of war next, then UK will make a negotiated peace. We end up with huge German power zone from Berlin to Baghdad.

We also know why they did it, they left records. It is a long quote from the book, but it explains many issues.

Why resort to unrestricted submarine warfare in 1917, when it didn’t correlate
with a greater rate of sinkings, but chanced a breakout of war with America?
“[...] the deterrent effect on the neutral powers, which was an essential factor of the wholeplan.

The German Navy hoped to frighten the European neutrals – Norway,
Sweden, Denmark and the Netherlands – from carrying on further commerce with Britain by means of a brutal threat of destruction in a declared ‘war zone’ around the British Isles. This alone would have decreased British imports/exports by 20-30%. However, Britain more successfully blackmailed the neutrals to continue their merchant trade by only releasing a neutral ship out for every neutral ship coming in. And somehow the neutral shipping companies had to earn their revenues and
profits, and the skippers and the sailors their daily lives, even risking it. After some weeks in February 1917 it was clear, that the German deterrence didn’t work. A first miscalculation.

 

[BlondieBC]

No it is not, the Germans took a battering at the Somme and Verdun and were fully committed. Had Russia been in a position to mount an offensive, or had Roumania entered the war sooner, the German had no reserves available to respond. Germany had got itself into a mess whose ultimate consequences were only postponed by the collapse of Russia. Had Imperial Russia been able to stage the kind of recovery in 1916 that the USSR did in 1942 the Germans would have been dead meat. As it was they squandered the respite they were given with USW, the Zimmerman telegram, and the mad gamble of the Michael Offensive

Spent is present tense. You are arguing a future WI from the winter of 1916/17 perspective. The Germans still had major offensives left in their army in 1917. They did a major 5 prong attack on Russia in 1917. We have the Spring 1918 offensive.

Now it is true that everyone was running low on reserves. Sure Romania entering the war sooner messes with the Germans and may well cause a faster loss than OTL. But if the Romanians don't enter the war (the opposite WI), then the Germans do much much better and the war probably goes into 1919 due to 1 million tons of extra cereal to eat, the German troops in Romania being used elsewhere. More oil products. A-H might well make it to 1919 now.

The Russians did not squander anything as a choice of the leadership. They ran out of foods. They were rapidly depleting their railstock which was hard to replace. We have issues with shortages of farm animals due them being used in the war. The Russians just ran out of stuff, then fell apart. Your what if is much like saying "IF A-H had plenty of supplies and popular will to fight late in the war, the Entente have huge issues". While true, one really is now discussing another TL not OTL.

 

[Glenn239]

No it is not, the Germans took a battering at the Somme and Verdun and were fully committed. Had Russia been in a position to mount an offensive, or had Roumania entered the war sooner, the German had no reserves available to respond.

The statement that the German army was on the verge of collapse in 1917 is false. Full stop.

 

[Glenn239]

Oh please. Your attempting to quibble and are tying yourself into knots.

You made two statements that were not true. These were corrected.

USW was much more effective. Sinkings triple under it.

This statement is also false.

USW did not "triple" the rate of sinkings. Here,

http://en.wikipedia.org/wiki/U-boat_Campaign_(World_War_I)

Shows cruiser rules with the U-boat fleet fully committed between October 1916 and January 1917, of an average of 347,000 tons sunk per month.

Under USW rules, in the 11 months between February 1917 and December 1917 the submarines sank 5,867,357 tons, or an average of 533,000 tons per month.

533,000 / 347,000 = 1.53 times more shipping sunk with USW than with cruiser rules.

If we add in 1918, of course the USW average drops to just over 400,000 tons, which is 1.14 times the cruiser rules average.

The British might have survived USW with American help but they were going to survive cruiser rule warfare too

This supposition seems correct.

However, the question is not whether the British could survive 350,000 tons per month, because I think we all agree they could. The question is whether the German navy could have 'upped' its tonnage sunk to the 1917 USW average of 550,000 tons per month by any means other than USW.

 

[LordKalvert]

The statement that the German army was on the verge of collapse in 1917 is false. Full stop.

You can keep saying that, but the truth is that the German field army peaks in January of 1917 and couldn't withstand another bloodletting like she got in 1916 especially as all her allies were collapsing as well.

Only the Russian Revolution saves Germany from defeat in 1917 and allows her to continue the war into 1918.

The Turks were already looking for terms from the Allies and the Russians and English were marching pretty much unopposed across Turkey. Bulgaria and Austria weren't going to survive either and the Germans knew it.

The Germans knew that and that's why they went on their mad gamble

 

[LordKalvert]

You made two statements that were not true. These were corrected.


This statement is also false.

USW did not "triple" the rate of sinkings. Here,

http://en.wikipedia.org/wiki/U-boat_Campaign_(World_War_I)

Shows cruiser rules with the U-boat fleet fully committed between October 1916 and January 1917, of an average of 347,000 tons sunk per month.

Under USW rules, in the 11 months between February 1917 and December 1917 the submarines sank 5,867,357 tons, or an average of 533,000 tons per month.

533,000 / 347,000 = 1.53 times more shipping sunk with USW than with cruiser rules.

If we add in 1918, of course the USW average drops to just over 400,000 tons, which is 1.14 times the cruiser rules average.

This supposition seems correct.

However, the question is not whether the British could survive 350,000 tons per month, because I think we all agree they could. The question is whether the German navy could have 'upped' its tonnage sunk to the 1917 USW average of 550,000 tons per month by any means other than USW.

And again you play with the numbers to fail to grasp the reality. The sinkings surge under USW which is what the Germans expected and they were right.

Yes, the Allies do employ countermeasures that bring that down later but those countermeasures could have been employed against cruiser rule warfare as well. They weren't because it wasn't necessary

And as has been repeatedly pointed out to you, and you just continue to ignore because it blows your theory out of the water, those countermeasures greatly reduced the capacity of the British merchant fleet.

USW was much more effective than cruiser rules- that is the fact

That the Germans miscalculated the effect of their USW on the situation is also correct- they really thought they could bring the British to their knees before the Americans got there.

That doesn't change the fact that on the seas, much more damage is being done to British shipping with the new rules

You are simply wrong

 

[Deleted member 1487]

You can keep saying that, but the truth is that the German field army peaks in January of 1917 and couldn't withstand another bloodletting like she got in 1916 especially as all her allies were collapsing as well.

Neither could the Entente, which is why 1917 was less bloody than 1916, yet the French did have a morale collapse and the Russians totally fell apart. The British were the best off and gave the Germans a tough series of battles in Flanders, culminating in the Battle of Passchendaele, yet Germany absorbed all of those, fought the French off at the Aisne, collapsed the Italians a Caporetto, defeated the Russians in several battles including the Riga offensive, etc. Germany was 2nd only to Britain is morale in 1917 and that was due to Britain suffering far less losses; in terms of fighting capacity Germany far exceeded Britain overall.

To what you're saying about the Ottomans, they were still fighting hard on all fronts in 1917 and were still fighting in 1918 and then for several years post war as the Allies tried to enforce to Treaty of Sevres and they Greeks tried to dismantle the Turkish Republic.

Germany was not in a good way in 1917 or 1918, but was ahead of the Entente except for the US and what it was able to contribute to the Allied cause. In fact without the US the Entente was lost in 1917. The Russian Revolution, Italian and French collapses, and overall Entente financial situation meant that Germany was in fact winning handily until the US entered the war and tipped the scale against Germany. The French army had peaked in 1916, the Russians' morale was gone by the end of 1916, the French were in mutiny, and the only ones left with fight by July 1917 were the British and they were having troubles politically after Passchendaele.

And again you play with the numbers to fail to grasp the reality. The sinkings surge under USW which is what the Germans expected and they were right.

Yes, the Allies do employ countermeasures that bring that down later but those countermeasures could have been employed against cruiser rule warfare as well. They weren't because it wasn't necessary

And as has been repeatedly pointed out to you, and you just continue to ignore because it blows your theory out of the water, those countermeasures greatly reduced the capacity of the British merchant fleet.

USW was much more effective than cruiser rules- that is the fact

That the Germans miscalculated the effect of their USW on the situation is also correct- they really thought they could bring the British to their knees before the Americans got there.

That doesn't change the fact that on the seas, much more damage is being done to British shipping with the new rules

You are simply wrong

You realize you're not actually making any factual points here, right? All you're doing is asserting unfounded opinions that have been disproven by analysis by BlondieBC and Mikestone. USW caused Germany far more harm that help:
http://www.amazon.com/The-First-World-War-Interpretation/dp/0198202792

 

[Mikestone8]

I agree with parts here. As to the explanation of USW warfare declaration, I lean towards other factors. It is pretty clear that Germany could change ROE without the world noticing since world reactions did not time with the sinking %. It is clear the Kaiser could be impulsive. We can go with the Germans did not care about the USA or neutral reaction, but there is a simpler explanation that I favor. The declaration was a deliberate effort to intimidate neutral SHIP OWNERS not to sail for the UK and Northern France. IMO, the target was more the large Norweign merchant marine fleet along with other powers such the Dutch. The Germans just miscalculated that the neutrals would not sail, they did in fact sail due to financial pressures such as bankruptcy. The Germans did not account for the large number of neutral merchant ships sitting in USA ports that would also be pressed into service.

And once the Entente included the USA, it enjoyed a virtual monopoly of bunker coal, so that for the remaining neutral shippers it was a straight choice of playing ball or going out of business. The Entente became effectively the only game in town.

And of course, had any neutrals opted to go out of business, American money would make it a simple matter to buy up their ships, which would thus come into Entente service another way.

Afaics, this "scaring the neutrals" business was simply the first excuse Admiral vH could come up with for choosing full USW over the "armed ships" option. He had decided that was what he wanted to do, and thought up some arguments later. Brilliant man.

 

[BlondieBC]

Afaics, this "scaring the neutrals" business was simply the first excuse Admiral vH could come up with for choosing full USW over the "armed ships" option. He had decided that was what he wanted to do, and thought up some arguments later. Brilliant man.

You may be right on that one. I have to go back and see if I can find quotes that are before the USA entered the war. So many WW1 generals and leaders lied after the war to cover up shortcomings in their decisions.

 

[Glenn239]

You can keep saying that, but the truth is that the German field army peaks in January of 1917 and couldn't withstand another bloodletting like she got in 1916 especially as all her allies were collapsing as well.

You stated the German army was on the verge of collapse in 1917. This statement is false. The German army was not on the verge of collapse in 1917.

 

[Glenn239]

And again you play with the numbers to fail to grasp the reality. The sinkings surge under USW which is what the Germans expected and they were right.

Your contention that USW was "three times" as effective as cruiser rules was false. The relevant statistics are linked for you. A case can be made for 1.5 times more effective, which was hardly compensation for war with the United States.

 

[BlondieBC]

However, the question is not whether the British could survive 350,000 tons per month, because I think we all agree they could. The question is whether the German navy could have 'upped' its tonnage sunk to the 1917 USW average of 550,000 tons per month by any means other than USW.

Ok, to work on the problem. Without big changes to the ship building program, the German Navy could keep about 30 uboats at sea in the Atlantic/North Sea and 10 in the Med Sea. If we don't have US destroyers, this will climb some, but there are other factors that will hurt such as learning of the Entente, so lets just use the 30/10 number for 1917.

I will try not to use numbers with less than 10/5 average subs on patrol to get a decent sample size. With just one or two subs out, it is really hit or miss on what you find.

The October 16 to Jan 17 time frame gives 188,000 tons per month in Atlantic on about 14.5 subs. Prorates to about 388,000 tons. My chart shows USW rules of engage (note still not really binary) in Med, so we can take the historical numbers. Looks like 100K is doable. So we get 488K.

We are still short. We need to boost U-boat production by 10%. Probably 30% be safer. Looks doable to me. Now there are a lot of "well, what about this". Hard to adjust for all, I tried in TL.

- As you add more subs, you will have to use less ideal hunting grounds. Negative factor.
- IMO, you could equip AMC in Germany and sneak the out. Adds up. Positive.
- UK is learning. Also gets better weapons. Negative.
- Going to convoy system cuts effeciency by about 1/3. Big potential positive.

So all said, I would think you get about 80 to 85% of the full effectiveness of USW or more. And no USA in war. Or at minimum slower USA in war. Remember butterflies can be a funny thing. All it takes is some captain misidentifying a ship to cause a huge issue.

And to be fair, my reading of USW shows that once USA is in the war, all sinkage advantages of USW go away. To me at least, the months of August 1917 and September 1917 indicate the allies had figured out some reasonable effective counter measures to USW.





Note. We also have to be careful with measuring ships, since there are different ways to measure tons. Gross displace versus cargo. I am using BRT figures.

 

[Glenn239]

The October 16 to Jan 17 time frame gives 188,000 tons per month in Atlantic on about 14.5 subs. Prorates to about 388,000 tons. My chart shows USW rules of engage (note still not really binary) in Med, so we can take the historical numbers. Looks like 100K is doable. So we get 488K.

Assuming 450,000 tons is the maximum sustainable submarine figure, and assuming that 600,000 tons sustained is the figure to force the UK out of the war, then the other 150,000 tons per month would have to come by way of surface raiders.