What if the Germans completed naval Plan Z?

A critical point you just made about the raiders slipping out into the Atlantic. By 45 even if there is no war both radar and arial survalance are going to make it much more difficult for a raider to break into the Atlantic and to remain undetected there. A hand full of light carriers for instance could keep the convoy lanes across the Atlantic pretty well covered as long as conditions permitted flying. Likewise the picket line across the access route North of Britain could be much more efficient. Few ships had radar in 1940 by 1945 even PT boats were equipped with it.

Not sure if we should be addressing it but there's also a chance the Nazi government doesn't survive into 45 or later. I can see this falling out several ways.

 

Lw, would the Alies have had sufficient stimulus to build centimetric radar with no war effort to sustain the technological race? Would the cavity magnetron valve have been slower to arrive without the wartime inspired scientific effort? Would the proximity fuse have been developed? Would de-gaussing have been discovered as a counter to the magnetic mine?

And as far as the Z plan was concerned, would the Kriegsmarine have intervened to change the battleship heavy aspect of the plan, and forced Hitler to build aircraft carriers instead of battleships ? Admiral Raeder may have been a 'big ship man' as described, but Hitler did not trust him or his surface navy collegues. Who knows? Donitz may have gotten to allocate materials for the magic 300-400 U-Boats he always said needed to be built. It's not outlandish to suggest that Raeder and Hitler may well have fallen out long before 'Z' plan comes of age. Once Donitz gets into Hitler's ear, they stop building big ships and come up with a more balanced approach, so that by 1945, they also have better Radar and communications, and might well have been able to perfect their naval codes to the point that two or even three 'Collossus' machines are insufficient to crack them.

All of these what ifs make the Kriegsmarine an animal with teeth, rather than a service demonstrating the value of honour preservation while their vessels are sliding beneath the waves one at a time.

 

Almost assuredly. If you look at the British efforts in this area it's pretty clear IMO. On the other hand it would likely be delayed somewhat and production even more so especially sense we wouldn't see the benefits of the collaboration between the US and GB at least for several years. My guess is that centermeter radar and the magnetron wouldn't be fielded for at least a year and possibly 2 later than the historical case.

Again there were multiple projects to develop proximaty fuzes but when they come to fruition without the war. Likely delayed at least a couple of years IMO although once the war starts if they aren't alread developed they might come pretty quick. Magnetic mines and for that matter magnetic torpedoes would likely lead to de-gaussing being discovered although that was pretty much a given once it was discovered that magnetic mines were being used. Everyone had problems with their prewar/early war magnetic torpedoes but this might allow time for that to be fixed.

IMO probably not. First of all there wouldn't be the examples of Toronto, Pearl Harbor, or Force Z. Then theres the fact that carriers are less useful in the Baltic and North Sea because there's so much land based air available and carriers are rather fragile. Furthermore the Germans had essentially no experiance in operating carriers and Hindinberg would likely illustrate that some of their thinking in this regard was seriously flawed. So I don't see much push for carriers until the Germans have some experiance with them and perhaps not even then.

Building that many uboats is going to really irritate the British and you are likely to see them devoting a lot of resources to ASW. Furthermore the slips start becoming a serious problem as does exactly what type of boat is being built. Also remember the Uboat war is seriously hampered if France doesn't fall if Norway doesn't either then it's almost a non starter even with that many boats.

Teeth perhaps although it's not clear at all that these changes are at all practicle and even if they are do they have the "legs" to move the "teeth" where they can be utilized. The fuel situation is still a very critical one and one that hasn't really been addressed yet.

 

The Z plan is simply Germany trying to re do the mistakes of WW1, the biggest is the lack of access to the sea. I would suspect Britain would use its older BB's as front line expendables and hold the newer ones for the finish off.

 

Mistake or not, they can't realistically expect to challenge the RN for supremacy, only cause a headache for the RN to chase them down. As such, it isn't really an option for a successful conclusion to the war. Now if they had followed plan Z, and if they had captured the French fleet intact, and if the Italians co-operated, and if they had enough Oil to keep everything moving, and if they didn't antagonize the US too much.... but by now we are rapidly approaching the realm of "rescued by the Klingons."

 

The Great Greek, on 02 Oct 2014 - 12:24 PM, said:

IMO probably not. First of all there wouldn't be the examples of Toronto, Pearl Harbor, or Force Z.

Second that. Nobody in the world was thinking of carriers displacing battleships as the arbiters of sea power. Carriers were seen as an important part of a balanced fleet, like cruisers or destroyers, and even early war experience bore that out. Carrier planes could help bring the enemy to battle, as at Matapan or the Bismarck chase, or strike him when he was out of reach of the battleships' guns, like Taranto or Pearl Harbor; the Japanese planes at Pearl Harbor were analogous to their torpedo boats at Port Arthur in 1904. Most of the major navies were building carriers, though not as many as they were battleships, much like the Z Plan proposed to do.

 

Building that many uboats is going to really irritate the British and you are likely to see them devoting a lot of resources to ASW.

Another important point. Unlike most aspects of German rearmament, a massive U-boat fleet could have only one purpose. It would confirm Germany as the enemy in the minds of the British people.

In the absence of war experience, Germany would continue building boats like the Type VII and IX, with the intention of using them as they did early in the war. Ironically, much of the unterseebootes' success stemmed from their ability to operate on the surface, before convoy escorts and maritime patrol aircraft had radar. In our scenario, although the development of radar might not be quite so urgent as in actual wartime, it would continue, as would the development of long-range aircraft, including commercial types like the Empire/Sunderland which could be adapted for military use. Our hypothetical U-boat armada starting a war in 1945 or so might not have such a "Happy Time".

 

Valid point, Carronade.

 

We might also consider whether the British would have added more aircraft carriers. They were already fairly air-minded of course; their fleet in 1939 included 15 capital ships and seven carriers of various types, and their construction program 11 battleships and six carriers (I was recently looking at Raven and Roberts and was reminded that, under peacetime conditions, the RN expected to have six Lion class by 1944 plus the five KGVs). The Z Plan included large numbers of panzerschiffe and battle cruisers, mainly for commerce raiding - how might the British plan to counter them?

The first thought might be to build a fleet of cruiser-killers or whatever, to roam the ocean and fight the enemy ship-to-ship in classic fashion; these would need to be comparable in speed, firepower, size, and expense to the German raiders but would be of little value in confronting the German battle fleet.

Aircraft could search and attack over a wide area and could offer a better means of bringing a fast raider to action than trying to find it and run it down by ship. A carrier accompanied by a fast battleship or battle cruiser could be as effective as several surface units. Any hit on a raider which reduced its speed would be essentially fatal. Additional British carriers would also counter the possible use of German carriers on the sea lanes.

The armored deck carriers were conceived with the expectation of facing land-based aircraft which would have superior performance to carrier planes, hence the idea that the ship would protect herself primarily by AA firepower and armor. Ships intended for open-ocean operations against the German fleet might revert to something like the Ark Royal design with a larger air group and more search and attack capability.

 

Even "jeep" carriers with a minimal attack wing could be a significant limitation on raiders. The would be capable of reconing an area on the order of a couple hundred miles in radius, at least during daylight hours and decent weather. Even without Iceland as a land base half a dozen could pretty well cover the route from Canada to Ireland. If they spot raiders convoys and hunters can both be advised of the spotting any damage done by strikes is just a bonus. They also would help in terms of uboats as well.

 

In my mind, an interesting "what if" is instead if the British succeeded in getting the Submarine completely banned, as they attempted in the Washington Naval Conference.

Another "what if" I've not seen explored, would've been the non-existence of the 1935 Anglo-German Naval treaty, together with an early adoption and planning for a Kreuzerkrieg fleet.

 

Those are both intriguing; perhaps you should start a couple of threads.

A key question re submarines is how this would apply to navies other than the five signatories to Washington. It would probably have to be followed up by an international conference. You could make an argument for submarines being reserved for small nations to protect themselves, although I can't think of any precedent concerning any other weapon. Would the prohibition continue down to the present day? Would developing nations/navies like India and China be denied submarines? How might the absence of SSBNs affect nuclear deterrence?

For the Kreuzerkrieg, is that just building the next three panzerschiffen allowed under Versailles, or does Hitler scrap the naval limitations at the same time as the army and air force? It would pose at least two dilemmas for Britain, although the first could pertain to any member of an arms limitation regime like the Washington and London treaties - how does a signatory respond to an emerging threat from a non-treaty power without wrecking the treaty system? Secondly, the question I touched on earlier, if Germany builds a fleet of specialized raiders, does Britain invest in a fleet of specialized anti-raiders, or try to find an asymmetric solution? Historically Britain encouraged the French to build the Dunkerques, but a larger threat would need a larger solution.

 

Not really...

IIRC, there was discussion of banning submarines during the 1899 Hague Peace Conference, but that went nowhere, since it required unanimity and the participant were equally split with 10 nations favoring a ban or a ban with reservations, 10 nations opposed, and 3 abstentions, . Also of note, is that the British were the only ones at the Washington Naval Conference to engage in banning the submarine, none of the other nations - not even Japan were interested in such a request. So, unless the British possess some mystical power, or make some very, very generous concessions elsewhere, such a ban is not happening,

Further, the British only "attempted" to do so...until the realized what a bloody stupid idea it was. Other nation's "Peace" politicians went along in the misguided belief that by doing away with submarines, you would do away with all of the small warships - thus leaving only the big ones to focus on. Everyone, eventually, came to the inevitable conclusion that it would be impossible to ban submarines, just as it would be impossible to enforce such a ban. Hence, the real impetus by the diplomats and military leaders, of the time, to regulate submarine warfare rather than ban it. Regretfully, the diplomats, still feeling the emotional effect of World War I, came up with this
https://www.icrc.org/applic/ihl/ihl.nsf/Treaty.xsp?action=openDocument&documentId=7F0E4920E26AB9C2C12563CD002D6907
Thankfully, France refused to ratify this Treaty, and being dependent on the ratification of all parties, it never went into effect. Still, the diplomats would do much better, as they continued to refine the regulations into treaties that were actually practicable in a "real world" setting and based less on their original post-World War I fervor.

Finally, more than a few have pointed out that the true failure of these efforts to regulate submarine warfare was due to the fact that no attempt was ever made at to ban or regulate the arming of merchantmen or carrying of contraband cargo. So long as neutral merchantmen were armed and allowed to carry contraband cargo, they argued, there would always be the spectre of unrestricted submarine warfare, since by it's very nature, armed merchantmen effectively prevented a submarine from practicing the rules of cruiser warfare.