Plan Z

[Galahad]

Everyone knows that if WW 2 hadn't intervened, Germany would have built a considerable and balanced battle fleet. What's odd is that no one--that I've seen--has ever commented on that fleet's Achilles heel.
A fleet of that size would require a HUGE amount of fuel. Germany would have spent itself into bankruptcy acquiring the fuel for it during peacetime, and been unable to send it to sea much during war. Germany simply didn't have the fuel to feed its enormous appetite.
The Italians had a large battle fleet, but it spent the most of the war in port, simply because the Italians couldn't afford to send it to sea due to the drain it made on their fuel reserves.
Plan Z would have put Germany in a similiar position, especially when the panzer force, and the Luftwaffe were increased in size.

[Takao]

I don't know how the lack of diesel fuel would effect the Panzerwaffe and Luftwaffe. The Panzer mostly ran on petrol and the luftwaffe needed high octane aviation fuel. Diesel fuel was easier to produce and needed less refining than the other fuels. It may have place a burden on the fuel supply, but it all depended on how often the ships put to sea in peacetime. Then again, who knows how German synthetic oil production would have progressed if war had not come. The German Navy would not be seeing the larger ships coming down the ways until 1943, that left them plenty of time to develop the refineries.

As for the Italian Navy, I don't think the lack of fuel effected it very much. The suffered from leadership lacking in "offensive" spirit. The Italian admirals knew their ships had better armament and speed then their British counterparts, however they also knew that their ships lacked defensive armor. The result was that the Italians did not press their attacks and usually stayed within range of land-based aircover. The Italian navy did negligible damage to the Royal Navy, but they suffered heavy losses.

[Galahad]

Ships like Bismarck and the Hippers didn't use diesel fuel. Neither would the later battleships and cruisers. In any case, whatever the fuel, it would have had to come from someplace, and the armored forces and the Luftwaffe would all be drawing from the same base souce for petroleum products.
Italy was totally reliant on German for supplies of petroleum products in WW 2. Given Germany's problems in that line, the supply wasn't as generous as the Italians would have liked. And it DID have a considerable impact on fleet movements. After deductions for industry, air force needs and the amount needed to fuel the convoys sent to Africa to supply Rommel, there wasn't much left for extended fleet operations.
The problems are the same as were faced by the Japanese when they made the decision to go to war: a strictly limited supply of petroleum versus a given requirement per month, based on industrial, merchant marine and operational needs.

[Takao]

I gotta stop these late-night posts, you are correct, the German ships burned fuel-oil and not diesel.

I had heard of a fuel shortage being responsible for Italy's lack of action in the Med only in briefly. Italy began the war with 1,800,000 tons of fuel oil, this had been planned to last for 10 months of war. However, after 9 months, they had only used some 1,000,000 tons, or 55% of there supply. Was this discrepancy because of prudence or lack of agressive action on the part of the Italian admirals, I believe it is the latter. The lackluster performance of Italian commanders, and a series of defeats early in the war: Calabria, Taranto, Matapan, led the Italians to become very overcautious when it came to sorties of the Italian fleet. When the fleet did sortie it behaved timidly. A situation not unlike that of the German navy. It's not like they had to steam all over the Pacific or Atlantic Oceans, the Italians never left the Med.

As for the Japanese, the circumstances were both similar and different. Japan bought most of it's oil from the US, and the US "shut off the tap", so to speak, leaving Japan without the means to meet it fuel needs(the US supplied 80%-90% of Japan's imported petroleum). Japan had a much larger navy than Italy, but it also had a much larger petroleum stocks, 6,500,000 tons as of 1 December, 1941. Given that the IJN high command estimated it would need 3,590,000 tons annualy for wartime operations, this gave it close to two years to conclude the war in the Pacific. In fact during the entire Pacific war the IJN consumed over 12,000,000 tons of oil, this amounted to roughly 60% of Japan's total wartime petroleum consumption. However, this rarely restricted Japanese naval sorties until mid-late 1944.

Where as the Japanese Navy fought tenaciously and won many victories, the Italian Navy spent more time avoiding engagements then fighting them.

[Dan Feltmate]

For Plan Z to be completed, Germany would have to win the war. That would have definetly been a big wall to overcome.

But let's be productive....Germany wins the war. I personally think that Germany would of had more than enough fuel to run there war machine. Oil fields in Romania and the Caucausas region would of been a plentiful supply. And the middle east, let's say the British got kicked out, would be in trade with the German reich to the North.

I just remembed also, the oil fields in the North Sea would of been accessible to the German surface fleet.

I guess all of it kinda depends on England....the Royal Navy....it's presence in the Middle East

[Takao]

Well, for Plan Z to have been completed one of two things had to happen. The first would be no war(of course) or 2. A successful conclusion of the war once begun. As neither of these two took place Plan Z was doomed.

I have been doing some further research on the proposed German designs, because I thought the Germans were leaning to using deisel fuel for better range and I found out the were. The H class battleships, the Kreuzer P class, and the O class battlecruiser were all to have had a combination diesel-turbine power plants. How this would effect the fuel situation is anybody's guess.

As it is the numbers, for new production, alone are staggaring. I wonder if the German industry would have been able to meet the yearly production schedule of Plan Z?

Another question I have is "Would it have any real effect on the naval balance given that Britain and America were producing their own classes of new ships as well?" British plans for new ships was upset by the war against the U-boats, where smaller destroyers were more urgently needed, and not the larger carriers or battleships. The British were to build 4 Lion class battleships, followed by the Vanguard class, and more aircraft carriers, however all the projects were posponed or scrapped. The Americans too were rebuilding there fleet. However, the war had the opposite effect and speeded up the construction of new vessels.

Just some food for thought.

[Centurion]

An additional stumbling block to the Z-Plan hopes, was the lack of overseas naval bases for resupply and repair of German vessels of all types. This lack alone would have, in my opinion, have prevented Germany's Z-Plan surface vessels from ever having a sizeable effect on the outcome of the war. And we haven't even begun to discuss the lack of an effective naval air arm (Graf Zeppelin and Peter Strasser not withstanding).
Regards, Centurion

[Tim Smith]

The Z-plan was a stupid idea. I think one of the main reasons, if not the main reason, Hitler and Raeder wanted a big surface fleet was for prestige reasons! Germany had suffered the humiliation of scuttling their fine WWI battle fleet in Scapa Flow in 1919, now Hitler wanted to replace it to show the world that Germany was a Great Power again.

The Z-Plan would have been the most expensive propaganda exercise in world history!

[Centurion]

All Hail,
Another factor that would have limited the effectiveness of Germany's Z-Plan, was that the Royal Navy, would not simply have sat idly by and watched Hitler's High Seas Fleet reform without making a formidable response. History shows that the British government and people were straining every nerve to match the Germans; but match the Germans they were, and then some. I think that the only way the Z-Plan might have had a positive effect for Germany, would have been if the Germans had not gone to war with the Soviets in 1941, but had instead concentrated the efforts on Britain alone. Fortunately, the Nazi leadership didn't do that...
Regards,

[panzertruppe2001]

Only a silly question. Why Plan Z and not Plan X or A or C?


Thanks

[ohrdruf]

The Koop & Schmolke series of books on German naval units from the "Tirpitz" down to light cruiser size makes clear the inadequacy of the constructions (other than the Panzerschiffe) for anything beyond coastal protection and bombardment.

Little needs to be said about the two major ships "Bismarck" and "Tirpitz". "Scharnhorst" and "Gneisenau" were useless in anything above a Force 4 because they were too wet, the machinery of the "Admiral Hipper"-Class were useless for extended endeavours because the machinery was too complicated and the units needed constant refuelling: of the six light cruisers only the oldest, "Emden" was oceanworthy, the other five relied on frequent refuelling to keep their bunkers topped up for stability.

In 1938 the German Navy had eventually accepted that the way forward was diesel and not steam, but by then it was too late.

A sea-change in naval construction occurred in 1940/41 with the design for a diesel destroyer, Z-51, of great range and endurance, and high speed. Probably not by coincidence, the displacement and armament was comparable to the oceanic raiding cruisers such as "Emden" and "Karlsruhe" of the Great War.

The possibility exists that German naval planners of the period had come up with the ideal solution for their particular needs: a large fleet of U-boats, and diesel destroyers able to act as commerce raiders and escorts. Z-51 was only partially completed, although her diesels were ready.

Whether such thinking would have changed the outlook of other nations following the 1935 Anglo-Naval Treaty is interesting conjecture.

[JohnWinston]

Can someone please help me clear up a few details?

1. Several books clearly state that there were going to be
A. 22-Scout cruisers
B. 12-Panzerschiff and
C. 12 Spahkreuzer

Is this correct? If not can someone please sort it all out?
Additionally, can someone (to the best they can) tell me:
A. where they were going to be built, or at least an educated guess
B. when they were going to be laid down and
C. an approximate launch date ( or about how long do ships of this class take from keel laying to launch and
D. an approximate commission date (or about how long do ships of this class take from launch date to completion.

Thank you very much,

Alan

[Tiornu]

The list given in your "Kriegsmarine Shipyard Capacities and Building Slips" thread is correct. Just keep in mind that different totals were planned at different times.
A Spahkreuzer is a scout cruiser. P1-12 were the Panzerschiffe.

[Keith Langley]

In answer to the question "Why Plan Z and not Plan X or A or C? " there was initially a plan X which was rejected followed by a plan Y which was also rejected
Finally there were two Plan Zs, one based around smaller ships including U-Boats and one around big ships. Admiral Raeder correctly guesed that Hitler would prefer the latter

I have a question of my own about the Z-Plan, most books and web site talk about the H-class battleships, the Graf Zeppelin and the O class battlecruisers. A few also give information about the M class cruisers and the Spahkreuzer but what about the destroyers, submarines and smaller craft?

For example the 68 destroyers, this figure probably included the existing ones but was there a definate design for the new contruction. Was the Narvik class part of the Z-Plan? What type of U-Boats were envisaged in the Z-Plan, were they all going to be type VIIs? How many Schnellboote were planned? Also, I assume the escort vessels F1-10 and G1-24 were part of the plan. Is there a really good book with detailed information about the ships planned? I've just bought a book advertized on the internet and it is more about the politics of Raeder and says virtually nothing about the ships planned

[Tiornu]

David Wragg has an English-language book on the plan due out this year from Pen & Sword.