The German merchant-submarines

Hello

I've watched the Great War's special on submarine warfare, and without a doubt the most interesting aspect of it, that I'd never heard of before, was the merchant submarine programme. In short, a submarine designed for trade rather than warfare, capable of carrying several tonnes of goods from as far as the US back to Germany. The Kaiser didn't approve of this project being put into large use and instead favored unrestricted submarine warfare. We all know how that went.

I'll be honest, I think this is the most fateful turn of ww1. Germany's isolation, both in terms of trade and diplomacy was always Germany's biggest weakness and couldn't be turned no matter how many battles they won in the field. The merchant submarines would change just this, allowing Germany to start importing goods from the US and the rest of the world, bringing news from the war from a german perspective and not antagonize the rest of the world with unrestriced submarine warfare.

What are your thoughts on all of this? Could it be enough to turn the war? Keep in mind that this would begin in 1916.
 
After surface ship blockade runners suffered disastrous losses early in '43, the Axis tried submarine blockade runners. The problem was that a submarine was very limited in what it could carry. Even if allied codebreaking and subsequent loss of subs hadn't been a problem, it's hard to see how enough cargo could've gotten through to make a difference, in WWII or WWI. The Germans considered building a large sub specially designed as a cargo carrier but even though (IIRC) it would've displaced well over 2,000 tons it could only carry 800 tons of cargo.
 
Think there was a thread about this not a long time ago. Several suggestions were put forward as to what the submarines should've carried to make the most of their use.
 
I've often thought about how this would work, or could work. The biggest problem is operational security. You have to keep this secret or the other side will develop countermeasures. Germany would have needed large waterfront warehouses/subpen that these vessels could clandestinely enter and exit while dropping/picking up their loads. They would need these in Germany and then in scattered parts of the world in order to get the desired cargo. Obviously the businesses couldn't be outright German owned so the whole network would have to be set up.

What would they get? As starman above says 800 tons would be about the max load so what cargo would you choose? Obviously Oil, Rubber and other specific metal ores would be high on the priority list. But even things like banana's, other fruits and beef could be important. One of my thoughts was manufactured things that Germany would need, but pulls away from the obvious military production. Things like construction equipment, farming equipment, fire fighting equipment and tools/machine tools. These are things that could be purchased and shipped that would relieve the German economy from having to produce (limited numbers). I mean think about it. How many fire trucks do you need to make in a year, 500? What does that do to an manufacturing line that could be making halftracks. Buying these things clandestinely in the US and then shipping them over in these merchant subs would be a great way to reduce the burden to the German economy.
 
They tried during WW1 with submarines Deutschland and Bremen. One was sank on its first voyage, can't remember what happened to the other.
 
Its pretty easy to operate a small number of these merchant subs, i.e. about 20, the USA has so many ports and such a long coast line, and is such a big market, its hard for the British to develop countermeasures in that scale. OR hard to buy up all the possible supplies in that scale.

For example a merchant sub shows up in Wilmington North Carolina, A British agent notifies the admiralty, which sends an AMC down, a weeks later, the sub sails, the sub can submerge as slow as it needs to inside USA waters, goes under the AMC, which with WW1 tech can't really detect and sink the sub. I can't think of good countermeasures. You can't mine USA ports. The next sub shows up in Charleston SC.

The cargo at this scale, has to be stuff to keep German manufacturing running, rubber for machine belts, metal ores for machine tools, copper for wiring. Outbound the OTL Deutschland carried dyes which is the kind of cargo needed, i.e. expensive stuff.
 
What would they get? As starman above says 800 tons would be about the max load so what cargo would you choose? Obviously Oil, Rubber and other specific metal ores would be high on the priority list. But even things like banana's, other fruits and beef could be important.

In WWII the Germans gave priority to imports of rubber, tungsten and tin, although they also wanted quinine, hides, vegetable oils etc. I don't think bananas or other perishable fruit would've been included.
 
I've often thought about how this would work, or could work. The biggest problem is operational security. You have to keep this secret or the other side will develop countermeasures. Germany would have needed large waterfront warehouses/subpen that these vessels could clandestinely enter and exit while dropping/picking up their loads. They would need these in Germany and then in scattered parts of the world in order to get the desired cargo. Obviously the businesses couldn't be outright German owned so the whole network would have to be set up.

What would they get? As starman above says 800 tons would be about the max load so what cargo would you choose? Obviously Oil, Rubber and other specific metal ores would be high on the priority list. But even things like banana's, other fruits and beef could be important. One of my thoughts was manufactured things that Germany would need, but pulls away from the obvious military production. Things like construction equipment, farming equipment, fire fighting equipment and tools/machine tools. These are things that could be purchased and shipped that would relieve the German economy from having to produce (limited numbers). I mean think about it. How many fire trucks do you need to make in a year, 500? What does that do to an manufacturing line that could be making halftracks. Buying these things clandestinely in the US and then shipping them over in these merchant subs would be a great way to reduce the burden to the German economy.

You're not going to be seeing things like bulky machinery (fire trucks) or relatively low value high bulk perishables (bananas) or high bulk products that would be virtually useless in the quantities possible ( oil). More like relatively compact extremely high value products like refined ingots of high value metals ( copper/alloys) rubber, some medicines, or the like.

Exports to pay for it would be things like gold, gems, refined chemical dyes, medicines, extremely high value goods like precision optics, and maybe some lower bulk precision machine tools.
 
One thing not yet mentiones is that it would open the USA up to news from Germany. And that will be another major impact in the stance of the USA in the war. Say whatever you want about the Germans but if news of hunger rations imposed by the blockade reach the USA how will they feel about the "upstanding and sporting British"?
 
Its pretty easy to operate a small number of these merchant subs, i.e. about 20, the USA has so many ports and such a long coast line, and is such a big market, its hard for the British to develop countermeasures in that scale. OR hard to buy up all the possible supplies in that scale.

For example a merchant sub shows up in Wilmington North Carolina, A British agent notifies the admiralty, which sends an AMC down, a weeks later, the sub sails, the sub can submerge as slow as it needs to inside USA waters, goes under the AMC, which with WW1 tech can't really detect and sink the sub. I can't think of good countermeasures. You can't mine USA ports. The next sub shows up in Charleston SC.

The cargo at this scale, has to be stuff to keep German manufacturing running, rubber for machine belts, metal ores for machine tools, copper for wiring. Outbound the OTL Deutschland carried dyes which is the kind of cargo needed, i.e. expensive stuff.


Definitely safer than a blockade runner and the principle has some value, but there are some issues.

-The fuel usage per ton of cargo is pretty poor - and fuel is a scarce resource when sailing from Germany. This also needs to weighed against other uses of the fuel.
-Any submarine is still vulnerable to the mine laying of German harbours, some will be lost in this way.
-The submarines can’t stay submerged the whole journey and move very slowly underwater. I think there will be greater dangers than you think leaving the safety of US waters.
-Building merchant submarines means according to the OP not building many U-boats, but building U-boats is what provided the skills to build the Merchant submarines...
-If there are many fewer German Submarines then the commerce side of the war for the UK gets a lot easier, this might translate to better Entente performance on the battlefield even if the US is later into the war. I think this might have been a worthwhile strategy, but allowing the Entente to retain the blockade by staying in the war longer could still mean the defeat of Germany by starvation.
 
To rely upon the merchant submarine to actually transport enough material to alter Germany's economic situation is likely too optimistic, but I think the value is in getting German communications with the USA, access to the critical supplies and if the British move to blockade the USA tipping the balance there. It tends to get underplayed but the USA was just as peeved over its neutral rights being impinged as it was angry with German USW, the USA was no true neutral, rather it wanted to do as it pleased and if Germany is sending submarines to trade which get interdicted off the coast of the USA that might be simply too much for Wilson. By the end of 1916 Wilson had choked off the Entente access to financing and was hoping to pressure all sides to his mediation. That is the window for a German commerce tact, running the British blockade in that time might reverse the Wilson logic and put him even more clearly opposed to British infringement of America's prerogatives.
 
The OTL Duetschland voyage showed the intrinsic value of such trade, the voyage traded goods far in excess of the value of the submarine. However I think the political value would be great: some Americans would benefit from the trade and thus lobby to continue it. Furthermore I think it might foster raising loans in in US, nothing like the hundreds of millions of dollars the Entente raised but big enough for a few more Americans to lobby to be repaid.

Perhaps if enough of this occurred the US entry into the war would be delayed enough to make a difference.
 
What are your thoughts on all of this? Could it be enough to turn the war? Keep in mind that this would begin in 1916.

So the first thing is what value of stuff the sub can carry. Here,

https://en.wikipedia.org/wiki/German_submarine_Deutschland

Deutschland departed on her first voyage to the US on 23 June 1916 commanded by Paul König, formerly of the North German Lloyd company. She carried 750 tons of cargo in total, including 125 tons of highly sought-after chemical dyes, mainly Anthraquinone and Alizarine derivatives in highly concentrated form,[4] some of which were worth as much as $1,254 a pound in 2005 money. She also carried medical drugs, mainly Salvarsan, gemstones, and mail, her cargo being worth $1.5 million in total.[5]


Here,

http://www.in2013dollars.com/1916-dollars-in-2005

In other words, $100 in 1916 is equivalent in purchasing power to $1,791.74 in 2005, a difference of $1,691.74 over 89 years.

125 tons of dye is 250,000 lbs, and the value per pound was as much as 1250*100/1790 = $70 US (1916) per pound, or 250,000*70 = 17.5 million dollars (1916) This corresponds exactly to the cargo taken back,

with a cargo of 341 tons of nickel, 93 tons of tin, and 348 tons of crude rubber (257 tons of which were carried outside the pressure hull). Her cargo was valued at $17.5 million, several times the submarine's construction costs.

So with these dyes at $70 per pound, how much of this was available to trade with the USA, and how many subs are we talking about? Then, what is the best bang per buck for 17.5 million in purchases, and could there be some credit leveraged?
 
Definitely safer than a blockade runner and the principle has some value, but there are some issues.

-The fuel usage per ton of cargo is pretty poor - and fuel is a scarce resource when sailing from Germany. This also needs to weighed against other uses of the fuel.
-Any submarine is still vulnerable to the mine laying of German harbours, some will be lost in this way.
-The submarines can’t stay submerged the whole journey and move very slowly underwater. I think there will be greater dangers than you think leaving the safety of US waters.
-Building merchant submarines means according to the OP not building many U-boats, but building U-boats is what provided the skills to build the Merchant submarines...
-If there are many fewer German Submarines then the commerce side of the war for the UK gets a lot easier, this might translate to better Entente performance on the battlefield even if the US is later into the war. I think this might have been a worthwhile strategy, but allowing the Entente to retain the blockade by staying in the war longer could still mean the defeat of Germany by starvation.


From the Wikipedia article:
https://en.wikipedia.org/wiki/German_submarine_Deutschland

"American submarine pioneer Simon Lake visited Deutschland while she was in Baltimore, and made an agreement with representatives of the North German Lloyd line to build cargo submarines in the US, a project which never came to fruition.[8]"

This is the ultimate solution, that the USA builds boats (the wikipedia article suggested this , for profits gained in blockade running, the Germans continue to build the vast majority of their boats for commerce raiding according to prize rules, other than that perhaps 4 or 5 for this trade.

To keep USA neutral, Germany would have to obey the prize rules (no USW), at least officially, (in places like the med where there were less USA ships about they could still take liberties), and yes this wouldn't be enough to force Britain out of the war, in hindsight we know keeping the USA out of the war is much greater than the value of shipping sunk.

What would be interesting if the Germans did more of this, avoided war with the USA, and ended up with a peace where they could build submarines, you could see the Germans building some huge 6000 ton merchant subs in the 20s and 30s for the next war.
 
Merchant ships £5 per ton 1913 prices. Submarines are £140 per ton. It’s not a really viable strategy.
Wrong oh!

On the surface of it, you would of course be correct, but comparisons of apples and oranges don't come out one-to-one.

Apples = Merchant shipping vs submarines where a party could pick either and achieve the commerce they desire.
Oranges = Merchant shipping vs submarines where only the submarine can survive (maybe) the submarine is the obvious choice vs no commerce.

Given that the OTL ship paid for itself several times over on it's first voyage, and it's cargo was valued at $17.5 million, let's check your numbers.

Deutschland was ~1500 tons X £140 = £210,000, so that seems right, then we would need to convert £ to $, in 1916 that was about $4.7 to one £, so $17,500,000 / 4.7 = £3,723,404, so using your numbers, we end up with something like 15 times the cost of the vessel from one trips cargo, so well worth it and definitely a money making proposition in it's own right, and when we factor in the lack of surface shipping survivability, and the desperate need to get strategic materials, yea, this looks to me like a no brainer.

So, if you want trade that has a chance to escape the blockade, the merchant submarine is the way to go.

One thing that I expected to see here and so far have not, is the value too the Germans of being able to tell the US public the truth about the submarine war on trade that Germany was at first waging, until the UK started having their merchant shipping fire on, radio the position of, or even ram the submarines, and how this forced the Germans to change tactics and use USW instead of cruiser rules. If the USA learns this, and the reasons behind it...

What if the Germans invite neutral American observers to travel back and forth on these subs, and see for themselves what the UK is actually doing, and what her blockade is doing to Germany's children? Could this make the USA decide to pull her shipping from UK waters, in a "You made this mess, so now you deal with it" kind of way? No US ships being sunk, no USA entry into the war, and USW is good to go.
 
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It would be interesting if one of the merchant sub fleet, since more than 2 will be built here, is painted in the Geneva scheme as a hospital ship and only carries medical supplies from the USA to Germany, and from Germany to the USA similarly German surgical tools and some specialized medications made in Germany. Have a representative of the US Red Cross on board. If the British attack or detain the boat, well big coup for Germany.
 
Dorknought is right that submarines aren't able to carry bulk loads, so can't replace a merchant marine. Shadow Master is right that submarines are a great way to get high value cargoes to and from the USA. The ultimate arrangement might be the submarines carrying the high-value dyes, etc., to/from the USA and the Germans surface fleet trying to move the bulk cargoes (nitrates, oil, etc) to Norway or Germany that the submarine cargoes made available for purchase.
 
Dorknought is right that submarines aren't able to carry bulk loads, so can't replace a merchant marine. Shadow Master is right that submarines are a great way to get high value cargoes to and from the USA. The ultimate arrangement might be the submarines carrying the high-value dyes, etc., to/from the USA and the Germans surface fleet trying to move the bulk cargoes (nitrates, oil, etc) to Norway or Germany that the submarine cargoes made available for purchase.
The problem with that is that Britain gave f**k all about the rights of the neutrals in WWI in their blockade of Germany. So whatever goods Germany hopes to gain through neutrals may be blocked by the RN from reacjing them.

On the other hand, a more involved Germany may force the USA to cry foul on this practice as it hinders the trade with them. And while ultimately going to Germany the USA has no open hostility with Germany until mid 17 OTL. So it could change perceptions in ways that change the war.
 
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