No Plan Z, early Uboat expansion

  • Thread starter Deleted member 1487
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On Plan Z, does anyone know what the Nazi expected the Soviet Navy to be in 1946 without a war? It is possible the Nazis had a high estimate of the size of the USSR fleet, and that plan Z was a rational number to be able to defeat this Soviet Navy of the future.


Do note that this view of the Soviet Baltic/Northern Fleets as a main threat for the KM is my POV and not a common view on most Plan Z studies, that tend, IMO wrongly, to view a WI fleet on a OTL context. Since Germany went to war with Britain, it must have of been what they wanted it for is the party line when it comes to Plan Z...
 
That still sounds a hell of a lot easier than someone trying to explain to Hitler why Germany, with land enemies to her east and west, should divert resources from the army and tactical air support into a submarine fleet that can only be effectively employed once Channel/Atlantic bases are obtained.

"Ignore France and the SU, the UK is the real threat! We must have a navy capable of defeating them!"
"Ok, so a big new battleship fleet then? Excellent, 100 kilotonne battleships, 20" guns, detachable sterns!"
"No, you see, that won't work, just as in WW1. We need submarines instead!"
"Which not only didn't work in WW1 either, but also probably lead to our defeat by bringing the US in against us?"
"Erm yes, but this time we will use French Atlantic ports as U-boat bases!"
"And what will the French say about this?"
"Who cares? Defeat them."
"So your plan is a UK-first strategy that is actually a France-first strategy that cripples our economy via blockade and leads to almost inevitable war with the US?"
"Erm... you don't have to be mad to work here but it helps?"
 

BlondieBC

Banned
That still sounds a hell of a lot easier than someone trying to explain to Hitler why Germany, with land enemies to her east and west, should divert resources from the army and tactical air support into a submarine fleet that can only be effectively employed once Channel/Atlantic bases are obtained.

"Ignore France and the SU, the UK is the real threat! We must have a navy capable of defeating them!"
"Ok, so a big new battleship fleet then? Excellent, 100 kilotonne battleships, 20" guns, detachable sterns!"
"No, you see, that won't work, just as in WW1. We need submarines instead!"
"Which not only didn't work in WW1 either, but also probably lead to our defeat by bringing the US in against us?"
"Erm yes, but this time we will use French Atlantic ports as U-boat bases!"
"And what will the French say about this?"
"Who cares? Defeat them."
"So your plan is a UK-first strategy that is actually a France-first strategy that cripples our economy via blockade and leads to almost inevitable war with the US?"
"Erm... you don't have to be mad to work here but it helps?"

You missed the POD. He is not diverting from Army or Air Force. He is diverting from surface ships to U-boats. And it is not a true diversion, just a reordering in time. He is building more U-boats in the early years, and fewer in the later years than planned. Now it would be in many ways a lucky decision for Germany, but luck happens.
 
King Augeas said:
We need submarines instead!"
"Which not only didn't work in WW1 either, but also probably lead to our defeat by bringing the US in against us?"
OK, this has to be put to rest.:rolleyes:

The subwar in WW1 did not bring in the U.S. Germany offering to give Texas back to Mexico did that.:eek::eek::rolleyes:

Nor is it likely the subwar alone, absent substantial sinkings of USN ships, would do it in WW2, either. Sinking a USN BB or something, maybe--but U-boats were under orders not to shoot at anything resembling USN, & it's not like the recognition manuals couldn't tell the difference...:rolleyes:
 
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Deleted member 1487

OK, this has to be put to rest.

The subwar in WW1 did not bring in the U.S. Germany offering to give Texas back to Mexico did that.:eek::eek::rolleyes:

Nor is it likely the subwar alone, absent substantial sinkings of USN ships, would do it in WW2, either. Sinking a USN BB or something, maybe--but U-boats were under orders not to shoot at anything resembling USN, & it's not like the recognition manuals couldn't tell the difference...:rolleyes:

The US entering the war was because of the Subwar. The Zimmermann Note just sped up the entrance of the US into the war.

That said the US had a much different attitude to European war than it did in WW1 and much more restrictive laws against the US supplying anyone with war material and money than they did in WW1.
 
wiking said:
The US entering the war was because of the Subwar. The Zimmermann Note just sped up the entrance of the US into the war.

That said the US had a much different attitude to European war than it did in WW1 and much more restrictive laws against the US supplying anyone with war material and money than they did in WW1.
I don't believe it. If it was about the subwar, U.S. entry wouldn't have waited til after Zimmermann. It followed Lusitania by about two full years, & about three of war. Yes, the U.S. held a view on freedom of the sea (much the same one as she did at the start of WW2), but it wasn't worth going to war over. It was a good excuse to hide the fact they'd read a top secret message sent to the German Ambassador...:eek:
BlondieBC said:
Well, the Germans might take out the oil fields with the extra air power, but they might find a much less useful way to use the airpower. Part of me thinks they do the same basic game plan in 1942 but with more forces.
Agreed, that looks most likely to me, too. Still, of the things that probably go well for Germany in SU, that strikes me the most consequential & obvious of Britain reducing her effort in NAfr.
BlondieBC said:
Of the options listed, I think taking Leningrad is most likely. Army Group South is probably still on the defensive at the start, so the extra forces go to the center or North Group. Likely enough to bust through the light defenses in the early days. Then a indecisive battle for Moscow that goes a bit better for the Germans. Then the need for resources in the South gets the same decision but with more forces. It stalls out somewhere.
That sounds right, but IDK nearly enough about the theatre to say with confidence.
BlondieBC said:
I would tend to agree Torch is likely in 1943. The logic is there. But the Allies might also be tempted for Norway or an attack on France.
An abortive *Dieppe is disturbingly probable.:eek::eek:
BlondieBC said:
Malta is interesting. I lot depends on if Taranto happens. If it does not, it looks pretty likely to me that Italy would invade Malta.
Possible. I have my doubts the Italians could succeed alone...:rolleyes:
BlondieBC said:
The Pacific is interesting. I would expect both the USA and UK to have fewer resources in the area. So the Japanese probably push until logistically exhausted.
Agreed.
BlondieBC said:
in 1943 or 1944, the USA does a Central Pacific strategy.
If MacArthur survives, IDK how you manage that.

Did I mention the changed emphasis & lack of CVs is likely to mean Nimitz relies more on subs? (Even if he doesn't shift to minelaying at IJN bases, which is the optimal solution.) Which is not good news for Japan...& means she's liable to be near an economic cliff sooner than OTL.:eek:

Plus, lack of CVs is going to delay any counterattacks til about November '43?
BlondieBC said:
Not sure on CVL and CVE. I am not sure built more. I am sure we use more in the Atlantic.
I'm thinking the need to replace merchant hulls is going to mean there's not enough yard space for the OTL proliferation (one might say profusion) of CVEs/CVLs. That being true, "more use" is liable to be off the table in the Atlantic. It certainly is in the Pacific.

Which presumes the NF patrol aircraft haven't so reduced convoy losses alone there's less need for CVEs to begin with.;) (Is that getting old?:p)
BlondieBC said:
I also would not be surprised to see the Pacific limited to 3-4 carriers until the U-boat war is won.
Possible. As I understand it, tho, the 2-Ocean Navy Act already had provided for more fleet CVs, so might be there are more. Unless the priority gets changed to merchant hulls along the way, & the CV schedules get pushed back.
BlondieBC said:
And there is the interesting question of peace. If the war in the Pacific is dragging on slower than OTL, might the USA or UK look for a peace deal? Or go for some goal other than unconditional surrender?
For Germany? Or Japan? In both cases, as it turned out, the "u.s." demand was more symbolic than real, & it actually stiffened resistance: when you have nothing to lose, you fight to the death.:eek:

Against Japan, if things are going badly enough early enough (& they might be), it's possible IMO to get surrender as early as the fall of Saipan, when the government changes.
BlondieBC said:
The bomb is used in Germany first.
Probable, if, indeed, it's used at all. That's the thing: change the schedule of events to take out Avalanche, you take out all the tonnage used to supply the troops, & civilians, for it, & put the burden on Germany. If you use that tonnage to build up (or keep afloat) Britain. you accelerate the date for Neptune, & so war's end...& it gets cut fine if the war ends before the Bomb is even ready.
BlondieBC said:
Lets go at this another way. <snip>
You've just described what Ops Research was doing. How they did it, IDK, but they managed to take quite scant (or scant-appearing to me, anyhow:rolleyes:) data & determine a/c-dropped DCs needed to be set shallower & in a stick of 6, & that bigger convoys were better. So, what happens if Winston or somebody simply listens to Blackett one day & says, "That sounds damned interesting. Can you prove it?" It's a readily butterflyable change IMO: change the conditions, you change how meetings go & what gets presented--if only slightly...& you only need slightly.:cool:

That said, I completely agree, doing it the other way is damned hard. Also changing Bomber Command's mind will never be easy.:eek:
BlondieBC said:
we know depth charges often cause the lost of contact with the submarine who will turn at the last moment. But how does one test this without using live ammo?
The obvious way: you ask RN submariners who have been depth charged... That's also why USN submariners did so well against IJN A/S: they trained against a better team.
 

Deleted member 1487

I don't believe it. If it was about the subwar, U.S. entry wouldn't have waited til after Zimmermann. It followed Lusitania by about two full years, & about three of war. Yes, the U.S. held a view on freedom of the sea (much the same one as she did at the start of WW2), but it wasn't worth going to war over. It was a good excuse to hide the fact they'd read a top secret message sent to the German Ambassador.

Germany declared unrestricted submarine warfare again in January of 1917. The US went to war in early April. It was the major reason for the US going to war. The Zimmermann Note finally broke down the last resistance in the country to going to war, so Wilson no longer had to wait until he could rangle up the votes in Congress. As it was right before the declaration of war there were several attacks on US ships plus the major economic consequences of suddenly not being able to have US shipping companies head to Europe.
Check out Devlin's "Too Proud to Fight" if you don't believe me.
 

Deleted member 1487

Anyway getting back on track:
assuming that, given the concerns raised by Michele, commissionings in 1939 remain the same as IOTL because production starting in March-April are not going to be ready for combat before 1940. So that means in January-June we have at least 100 Uboats coming online from new construction started in 1939 as part of Plan Z. The goal is to meet Uboat requirements first to as to get that part of Plan Z out of the way to free up dock space for surface ships once the capital investments are scheduled to be completed in 1941-2 and the Polish economy can be integrated into the Reich.

Whether or not prefabrication is done in these new mass constructions is up in the air, but possible IMHO. But for the sake of argument lets say that Type VII subs take 14 months from laying to commissioning in this scenario.
Sinking rates in 1939 remain the same. In 1940 though they spike sharply, especially as the French Atlantic ports open up. Perhaps for the year some 150-75 Uboats are commissioned in 1940, the majority in the first 6 months, as the batches of major construction started in 1939 roll off the slips. Prefabing starts at the latest with the 2nd series after the initial batches are laid down in Spring 1939. By 1941 we've got over 20 Uboats getting completed per month (IOTL by 1942-3 it was ~26 per month), with commissionings about 4 months later.

1940 would see the 'boom' in construction numbers and rates, as that would be the point that the production pathways are grooved based on the 1939 experience and expansion. 1941 is when these would largely appear in combat, again in Spring, as they would start being laid down as the 1939 batches were completed, but these appear earlier, as several months are knocked off production because of production experience and economies of scale, resulting in an 11-12 month schedule of laying to commissioning.
From January to May we see larger numbers roll off the slips again and enter combat patrols. Of course we see various smaller batches ready throughout the rest of the year that started later than the initial batches for various reasons.

Does that seem about right?
 
wiking said:
Germany declared unrestricted submarine warfare again in January of 1917....
Check out Devlin's "Too Proud to Fight" if you don't believe me.
It's not your word I disbelieve,:eek: it's the proposition itself. However, I'll give Devlin a look.

And offer apologies in advance.:eek:
 

Deleted member 1487

It's not your word I disbelieve,:eek: it's the proposition itself. However, I'll give Devlin a look.

And offer apologies in advance.:eek:

http://en.wikipedia.org/wiki/U-boat..._Resumption_of_unrestricted_submarine_warfare

On 31 January, the Kaiser duly signed the order for unrestricted submarine warfare to resume effective 1 February; Bethmann-Hollweg, who had opposed the decision, said "Germany is finished".[19]
On 3 February, in response to the new submarine campaign, President Wilson severed all diplomatic relations with Germany, and the U.S. Congress declared war on 6 April.
 

BlondieBC

Banned

Looks about right. 18 months from the go by Hitler to a lot more U-boats begin to hit the water. You get a big slug of U-boats followed by a planned building pause that is cancel by the war. You get a 12-18 month window to win the war, or at least cripple the UK enough that the USSR can be driven out of the war.
 

Deleted member 1487

Looks about right. 18 months from the go by Hitler to a lot more U-boats begin to hit the water. You get a big slug of U-boats followed by a planned building pause that is cancel by the war. You get a 12-18 month window to win the war, or at least cripple the UK enough that the USSR can be driven out of the war.

If the goal was to get over 200 Uboats, I'd imagine there would be two large batches planned, one in 1939 to be ready in 1940 and one in 1940 to be ready in 1941 to free up the docks for surface ships that would enter construction that year because now there is a flood of steel ready for them and the H-class battleships could get time to get their specs revised as needed.

In between the big batches there would be smaller batches, as dock space is freed up from previous construction being completed throughout 1939 and 1940. Perhaps two batches of 75 units would be enough, with the smaller batches in between the bigger ones and continued construction thereafter to phase out older boats. Perhaps there would be larger batches because included in that would be the latest models of Uboats that would replace the earlier ones for the final fleet (i.e. 100 models per batch, as the Type IIs and Type VIIAs and Bs would be getting phased out by 1941 and on for fleet service, making the existing uboat fleet in 1939 obsolete), with smaller in between batches and continuing construction in 1942-5 making up the balance of the planned Uboat fleet.
 
Imports

Right up to its entry in the war Italy gave priority to exporting weapons over supplying its armed forces. ( they were about to sell 200 Caproni bombers to France and 300 to Britain literally days before declaring war. In September 39 they would probably agre to sell the Marconi and Liuzi class boats being completed to the KM. This allows the boats to be built with German style equipment and gives you 10 adicional useful boats. The same goes for the Cagnis. (giving you 4 boats ideal for operations against the US coast right in time. This might only be 14 boats, but in this case quality as a quantity of its own.
And before everyone goes "they would keep the boats for themselves" remember that even in 1941 Italy sold Portugal a large batch of 75/18 M35 howitzers that were desperately needed in Africa by their own Army. (Re2000 fighters to Sweeden, along with two older DD and two Spica DE...)
You can throw in the two Glaucos and the two Argus that Portugal ordered in the 30s, and failed to buy, as an early KM purchase to establish the trend...
 
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Deleted member 1487

Right up to its entry in the war Italy gave priority to exporting weapons over supplying its armed forces. ( they were about to sell 200 Caproni bombers to France and 300 to Britain literally days before declaring war. In September 39 they would probably agre to sell the Marconi and Liuzi class boats being completed to the KM. This allows the boats to be built with German style equipment and gives you 10 adicional useful boats. The same goes for the Cagnis. (giving you 4 boats ideal for operations against the US coast right in time. This might only be 14 boats, but in this case quality as a quantity of its own.
And before everyone goes "they would keep the boats for themselves" remember that even in 1941 Italy sold Portugal a large batch of 75/18 M35 howitzers that were desperately needed in Africa by their own Army. (Re2000 fighters to Sweeden, along with two older DD and two Spica DE...)
You can throw in the two Glaucos and the two Argus that Portugal ordered in the 30s, and failed to buy, as an early KM purchase to establish the trend...

Well if Italy has an easier time in Africa because of the threat to British shipping, perhaps they will have more the sell. Of course it probably would be better just to have the Italians run the subs themselves, so that the Germans can save on manpower and foreign exchange. Still there are plenty of what ifs stemming from Germany selling Italy its engine designs, which would serious help Italian aircraft performance.
 

Rubicon

Banned
Still there are plenty of what ifs stemming from Germany selling Italy its engine designs, which would serious help Italian aircraft performance.
Not to mention tank-design, engines powerful enough was a serious limitation for the Italians.
 
Soviet plans

On Plan Z, does anyone know what the Nazi expected the Soviet Navy to be in 1946 without a war? It is possible the Nazis had a high estimate of the size of the USSR fleet, and that plan Z was a rational number to be able to defeat this Soviet Navy of the future.


Took a while, but found a good, short article on the subject.

The Development of Strategic Concepts and Shipbuilding
Programmes for the Soviet Navy, 1922-1953: Stalin's​
Battleships and Battlecruisers

http://www.cnrs-scrn.org/northern_mariner/vol07/tnm_7_3_51-61.pdf
 
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