WW1 Submarines and the Blockades

JohnOfNottingham · Aug 16, 2014

I'm not quite sure if this is the proper forum for this, but it seemed so - so sorry if it isn't. Would Help/Feedback been the correct place?

But to topic:
I've been thinking on WWI recently, and changes in history in it, but that isn't what I wanted to ask. What I wanted to ask is specifically about the blockades the British and Germans imposed on each other, and the German usage of submarines.

To be exact, as far as I remember/know the British in their blockade used ships, while the Germans used (unlimited, for a while also limited, but that's not the point) submarine warfare. So I have to ask, would there have been a way for the Germans to use the submarines "defensively" instead of imposing a blockade on Britain? With "defensively" I mean against the British blockade. For example harassing specifics ships that would stand in the way of neutral or German transporters heading for German ports? Or possibly even attacking the blockade in general, and cause enough casualties at sea for the British to (consider) abort(ing) their blockade?

Otherwise, if anti-submarine had developed(I'm no expert in the history of naval warfare) to the stage of making submarine attacks on warships ineffective, was there, or could there have been, a chance of Britain aborting the blockade and using its resources to strengthen the defense of its own shipping against the Germans?

hasdrubal barca · Aug 16, 2014

JohnOfNottingham said:
I'm not quite sure if this is the proper forum for this, but it seemed so - so sorry if it isn't. Would Help/Feedback been the correct place?

But to topic:
I've been thinking on WWI recently, and changes in history in it, but that isn't what I wanted to ask. What I wanted to ask is specifically about the blockades the British and Germans imposed on each other, and the German usage of submarines.

To be exact, as far as I remember/know the British in their blockade used ships, while the Germans used (unlimited, for a while also limited, but that's not the point) submarine warfare. So I have to ask, would there have been a way for the Germans to use the submarines "defensively" instead of imposing a blockade on Britain? With "defensively" I mean against the British blockade. For example harassing specifics ships that would stand in the way of neutral or German transporters heading for German ports? Or possibly even attacking the blockade in general, and cause enough casualties at sea for the British to (consider) abort(ing) their blockade?

Otherwise, if anti-submarine had developed(I'm no expert in the history of naval warfare) to the stage of making submarine attacks on warships ineffective, was there, or could there have been, a chance of Britain aborting the blockade and using its resources to strengthen the defense of its own shipping against the Germans?

The British did not conduct a close blockade right up on the coast, so it made any attempts by Germany to deal damage much harder.

This may interest you: https://www.alternatehistory.com/discussion/showthread.php?t=301039

JohnOfNottingham · Aug 16, 2014

I am fully aware that they weren't directly on the German coast. (IIRC it was between Scotland and Norway to the North and between France and England in the west?) but I don't quite see how it would make attacking the blockade harder, considering they still could attack british shipping which probably means they still passed through and beyond the blockade.

But thanks for that thread, I'll take a look at it.

hasdrubal barca · Aug 16, 2014

JohnOfNottingham said:
I am fully aware that they weren't directly on the German coast. (IIRC it was between Scotland and Norway to the North and between France and England in the west?) but I don't quite see how it would make attacking the blockade harder, considering they still could attack british shipping which probably means they still passed through and beyond the blockade.

But thanks for that thread, I'll take a look at it.

I not having a close blockade makes locating a targeting ships harder.

In regard to your plan do you think the Germans could injure the British enough where they would give up a blockade? Britain does have the superiority in numbers and can probably afford some losses.

Perhaps the goal should be to degrade the blockading fleet, with subs, enough that the German fleet can sally out and fight it on equal terms.

JohnOfNottingham · Aug 16, 2014

hasdrubal barca said:
I not having a close blockade makes locating a targeting ships harder.
...

Mhm.... makes sense, I suppose. But they did attack ships beyond the blockade, IIRC, so while it might make it take longer, it still should be possible.

...
In regard to your plan do you think the Germans could injure the British enough where they would give up a blockade? Britain does have the superiority in numbers and can probably afford some losses.
...

To be honest, I was more thinking of it becoming too costly in terms of lost ships and men, and/or too costly for the British populace to see a gain in it, rather that a proper defeat of the navy through those measures alone.

...
Perhaps the goal should be to degrade the blockading fleet, with subs, enough that the German fleet can sally out and fight it on equal terms.

That would be an option as well. Do you know how reasonable that is?

hasdrubal barca · Aug 16, 2014

JohnOfNottingham said:
Mhm.... makes sense, I suppose. But they did attack ships beyond the blockade, IIRC, so while it might make it take longer, it still should be possible.
To be honest, I was more thinking of it becoming too costly in terms of lost ships and men, and/or too costly for the British populace to see a gain in it, rather that a proper defeat of the navy through those measures alone.
That would be an option as well. Do you know how reasonable that is?

Not sure reducing Britain's battleship strength down to 16, where the Germans are at, seems improbable. The British light forces could probably be degraded to where they are on par with Germany.

Not sure what advantage that gives though

JohnOfNottingham · Aug 16, 2014

hasdrubal barca said:
Not sure reducing Britain's battleship strength down to 16, where the Germans are at, seems improbable. The British light forces could probably be degraded to where they are on par with Germany.

Not sure what advantage that gives though

So, all in all, it wouldn't quite be possible for Germany to effectively use the submarines to defeat the blockade, even if only attempting to severely weaken the British. Good to know, thanks for answering.

Tallil2long · Aug 17, 2014

The RN made extensive use of blockades throughout the 18th and 19th centuries. In 1897, FO under-secretary Bertie threatened the Germans with blockade. In WW1, the British seems never to have seriously questioned whether blockading Germany was a good strategy, they simply launched one as a matter of course.

From these facts, I conclude that blockade was a technique that the British were wedded to, and they would only give it up if compelled.

So, could German submarine attack on the RN compel the British to give up the blockade?

I think probably not.

The only RN elements that the British had to conserve were the capital ships. They absolutely had to maintain a capital ship superiority in order to contain the HSF. All other ships -- drifters, subchasers, destroyers, light cruisers, merchant auxiliaries, etc, were replaceable even at high rates of expenditure.

And IIRC it was these same lighter units which were the primary blockaders. The u-boats would have to sink very large numbers of these in order to overwhelm replacement rates and compromise the blockade.

It is true that ASW was pretty basic at this time. But then, contemporary submarines themselves were actually quite primitive. Subs had a great deal of success going after slow merchant traveling independently or in weakly-escorted convoys. But going after light naval units on blockade would be attacking enemy strength rather than attacking enemy weakness. Going after the "thickest part of the fence", as it were. Kills on blockaders would be matched by higher losses of u-boats. And I'm pretty sure Britain could win that particular attritional battle.

In the meantime, the blockade becomes even more valuable, as it is now both constricting German trade and protecting Britain's merchant traffic (indirectly) by soaking up Germany's submarine warfare efforts. Britain devotes more resources to maintaining the blockade, and with her overseas shipping routes under no u-boat threat, has more resources to devote.

All things considered, unless I'm missing something, subs against blockade is a very much worse strategy than subs against shipping routes.

Riain · Aug 17, 2014

Geography make the blockade very easy and efficient for Britain to enforce, since blockade runners would have to pass close to British territory and naval bases. Therefore there was no need to have a lot of ships out chasing the blockade runners, they had to come to Britain, therefore trying to attack the blockade by sinking ships would be virtually pointless.

JohnOfNottingham · Aug 17, 2014

Tallil2long said:
The RN made extensive use of blockades throughout the 18th and 19th centuries. In 1897, FO under-secretary Bertie threatened the Germans with blockade. In WW1, the British seems never to have seriously questioned whether blockading Germany was a good strategy, they simply launched one as a matter of course.

From these facts, I conclude that blockade was a technique that the British were wedded to, and they would only give it up if compelled.

So, could German submarine attack on the RN compel the British to give up the blockade?

I think probably not.

The only RN elements that the British had to conserve were the capital ships. They absolutely had to maintain a capital ship superiority in order to contain the HSF. All other ships -- drifters, subchasers, destroyers, light cruisers, merchant auxiliaries, etc, were replaceable even at high rates of expenditure.

And IIRC it was these same lighter units which were the primary blockaders. The u-boats would have to sink very large numbers of these in order to overwhelm replacement rates and compromise the blockade.

It is true that ASW was pretty basic at this time. But then, contemporary submarines themselves were actually quite primitive. Subs had a great deal of success going after slow merchant traveling independently or in weakly-escorted convoys. But going after light naval units on blockade would be attacking enemy strength rather than attacking enemy weakness. Going after the "thickest part of the fence", as it were. Kills on blockaders would be matched by higher losses of u-boats. And I'm pretty sure Britain could win that particular attritional battle.

In the meantime, the blockade becomes even more valuable, as it is now both constricting German trade and protecting Britain's merchant traffic (indirectly) by soaking up Germany's submarine warfare efforts. Britain devotes more resources to maintaining the blockade, and with her overseas shipping routes under no u-boat threat, has more resources to devote.

All things considered, unless I'm missing something, subs against blockade is a very much worse strategy than subs against shipping routes.

I see. Well, then that idea can be cut out - thanks for answering.

Riain said:
Geography make the blockade very easy and efficient for Britain to enforce, since blockade runners would have to pass close to British territory and naval bases. Therefore there was no need to have a lot of ships out chasing the blockade runners, they had to come to Britain, therefore trying to attack the blockade by sinking ships would be virtually pointless.

But wouldn't that also have made attacking the blockading ships quite easy, as one would know when they'd leave base, and could regularly prepare for them to do so?

In addition, most answers seem to focus on the first of the two ideas, so I'd like to again mention:

JohnOfNottingham said:
...

Otherwise, if anti-submarine had developed(I'm no expert in the history of naval warfare) to the stage of making submarine attacks on warships ineffective, was there, or could there have been, a chance of Britain aborting the blockade and using its resources to strengthen the defense of its own shipping against the Germans?

While the first question has been answered and explained to be inefficient, if even possible at all, I'm still curious about this one.

BlondieBC · Aug 17, 2014

JohnOfNottingham said:
So, all in all, it wouldn't quite be possible for Germany to effectively use the submarines to defeat the blockade, even if only attempting to severely weaken the British. Good to know, thanks for answering.

For majority of patrol by U-boats before 1918 were military (i.e. not merchant warfare). There are some big successes, but you are not going to break the RN or the RN blockade with U-boats.

As long as the UK has backup warships in Portsmouth and Scapa Flow, you can use junky merchant ships and older light warships for a blockade enforcement. And a lot of the blockade had financial elements such as buying up supplies. Or just buying the cargo of ships head to neutral countries that can reexport to the Central Powers..

JohnOfNottingham · Aug 17, 2014

BlondieBC said:
For majority of patrol by U-boats before 1918 were military (i.e. not merchant warfare). There are some big successes, but you are not going to break the RN or the RN blockade with U-boats.

As long as the UK has backup warships in Portsmouth and Scapa Flow, you can use junky merchant ships and older light warships for a blockade enforcement. And a lot of the blockade had financial elements such as buying up supplies. Or just buying the cargo of ships head to neutral countries that can reexport to the Central Powers..

Mhm, thanks. And do you know about my second question?

sitalkes · Aug 17, 2014

"On 1 January 1918, Keyes took over command of The Dover Patrol.[4] Prior to Keyes, the Dover Patrol had been commanded by Admiral Bacon and had succeeded in sinking two German U-Boats in the English Channel in the previous two years, but out of 88,000 crossings by ships only five had been torpedoed and one sunk by gunfire.[10] After Keyes took control, he altered tactics, and the Dover Patrol sank five U-Boats in the first month after implementation of Keyes' plan" - wikipedia

As I understand it, there was a mine barrage across the English Channel, did the U-boats get past it before Keyes was in charge, and why was it so ineffective until then?

tigercat · Aug 17, 2014

Google the Live Bait Squadron. This disaster shows even in the face of adversity the British continued with the blockade.

JohnOfNottingham · Aug 18, 2014

tigercat said:
Google the Live Bait Squadron. This disaster shows even in the face of adversity the British continued with the blockade.

Yeah, I already had heard of that incident. But that was one. What would happen if this disaster would start becoming a common occurrence?

sitalkes said:
"On 1 January 1918, Keyes took over command of The Dover Patrol.[4] Prior to Keyes, the Dover Patrol had been commanded by Admiral Bacon and had succeeded in sinking two German U-Boats in the English Channel in the previous two years, but out of 88,000 crossings by ships only five had been torpedoed and one sunk by gunfire.[10] After Keyes took control, he altered tactics, and the Dover Patrol sank five U-Boats in the first month after implementation of Keyes' plan" - wikipedia

As I understand it, there was a mine barrage across the English Channel, did the U-boats get past it before Keyes was in charge, and why was it so ineffective until then?

I don't know.

BlondieBC · Aug 18, 2014

JohnOfNottingham said:
Mhm, thanks. And do you know about my second question?

What was the second question?

BlondieBC · Aug 18, 2014

sitalkes said:
As I understand it, there was a mine barrage across the English Channel, did the U-boats get past it before Keyes was in charge, and why was it so ineffective until then?

1) Ships were not on it at night and in bad weather for much of the war.

2) Best sailors and officers tended to be on the bigger warships.

3) You only need one hole to get through.

4) Seems like some issue with density of mines.

BlondieBC · Aug 18, 2014

JohnOfNottingham said:
Yeah, I already had heard of that incident. But that was one. What would happen if this disaster would start becoming a common occurrence?

The UK pulls ships from near enemy shores. They lost 3 capital ships around Gallipoli to smaller ships, then pulled back to port.

BELFAST · Aug 18, 2014

The big problem for the German navy was the British could read the German Naval codes.

JohnOfNottingham · Aug 18, 2014

BlondieBC said:
What was the second question?

JohnOfNottingham said:
Otherwise, if anti-submarine had developed(I'm no expert in the history of naval warfare) to the stage of making submarine attacks on warships ineffective, was there, or could there have been, a chance of Britain aborting the blockade and using its resources to strengthen the defense of its own shipping against the Germans?

BELFAST said:
The big problem for the German navy was the British could read the German Naval codes.

Really? I know of Enigma during WW2, but I don't remember that on WW1.

BlondieBC said:
The UK pulls ships from near enemy shores. They lost 3 capital ships around Gallipoli to smaller ships, then pulled back to port.

So they would pull back to their ports, effectively abandoning the blockade? Or do you mean that they would pull ships to the blockade?