The betrayal of the Kaiserliche Marine and the resurrection of the Reichsmarine

The overall philosophy is to have a niche were each ship category can beat its counterpart in the RN with low loss probability. Basically, negate the RN numerical advantage by avoiding the attrition seen in WW1.

Similar to what IJN tried to do with Yamato's et al.
 
Definitely. The British 5.25" DP was really the limit of what could be done, and a little smaller is better.
With manual loading yes. This is the series of weapons we are dealing with:
https://weaponsandwarfare.com/15-cm-flak-50-55-60-60f/
They were not too successful as the leap in performance over the 128 mm did not justify the investment (why not just make 2 128 mm?). However on a precious spot (a warship with limited space) and with a high performance both as AA and as surface weapon it is quite justified.
 
Last edited:
Chapter 35: French and British response to the German build-up.
Chapter 35: French and British response to the German build-up.

The expansion of the German navy up until 1933 had not left either the British or the French sleepless. However, the earlier heavy German cruisers coupled with the Italian building of their Trento class cruisers had necessitated a response from the French who did not have the number of cruisers possessed by the British. France had moved on with a 23.300 tons battleship design to be coined the Dunkirque class in 1931 and armed with 2x4 305 mm guns laying down the second ship in 1933. The design was made to counter the Trento and Deutschland class of 8 inch guns while outclassing them with its own 305 mm, and reserving the possibility of building 3 ships on the 70000 tons allotted space from the London Naval treaty..

Essentially, that the Germans had or were close to reaching their ToV allowance with ships that seemed manageable by existing ship classes were not too disturbing. This, assuredness changed after 1933 as it became clear that the German state were bustling with activity. With regards to the Navy, the lock at Wilhelmshaven were expanded, officially to also accommodate the large new liners build for Lloyds and a 330 m long drydock would be constructed in both Bremen and Kiel, while a smaller dock of 250 m would be constructed in Bremen. Again officially, this matched the large civilian expansion and the need for repair of multiple civilian ships. As these were now often running on German diesel engines, German shipyards had a competitive advantage when offering repairs and had good reason to capitalize on this advantage.

So while all of it might be legitimate, the thought experiment, what if it is all a ruse to cover rearmament, did contribute to anxiety. Consequently, the French laid down their third ship of the class in early 1934 to a slightly modified and overweight design with better armor and started to invest sufficient funds in the two ships already laid down. These had lingered forward at a slow pace with commitments dwindling during the financial crisis which roared through France in the early 1930’s.

In early 1935, rumors that a triple 11 inch turret were being installed on the Deutschland class and that admiral Scheer had been recommissioned with new guns reached the French admiralty, that immediately did two things. Demanded an explanation by the Germans (who denied everything) and initiated the finalization of what would become an evolution of the Dunkirque design: A small battleship designed to outperform 11 inch gun armed cruisers and also to shrug of the guns of the existing older Italian battleships. The Italians had stayed silent during 1933-and into early 1935, but all this changed in the summer of 1935 when in short succession:

Adolf Hitler announced that the newly formed Luftwaffe had achieved parity in the air;

Adolf Hitler announced the signing of the Anglo-German Naval agreement;

Benito Mussolini announced that the Italians announced that they had initiated building of two 35000 tons battleships;

and Adolf Hitler announced that Germany was well under way to generate a 36 division army.

These announcements left the French naval defense plans in disarray with two insufficient ships on the slipways and one launched and fitting out and without a design ready to counter the new threat, nor the infrastructure to support it. Furthermore, in 1935, the financial crisis peaked in France and the struggle for the necessary investments were fierce. For all these reasons, the lack of the design foremost, it would not be until June 1936 and February 1937 that the follow-on designs of the 35000 Richelieu class with 2x4 380 mm guns would be laid down. This French departure from existing treaties would naturely be used by France’s enemies in the future.
 
From what I've read the German 150mm AA gun had about a 400m altitude advantage over the 128mm together with an extra 10m lethal burst effect radius. But it was more expensive to build and transport so the 128mm (especially the twin) was more than likely a far better investment.
 
From what I've read the German 150mm AA gun had about a 400m altitude advantage over the 128mm together with an extra 10m lethal burst effect radius. But it was more expensive to build and transport so the 128mm (especially the twin) was more than likely a far better investment.
Most, but not all the required info is in the table (in German) of the link I provided.
The height advantage compared to the 128 mm can be up to 1500 m’s for the normal range versions. The 1200 m/s version is really extreme with 88 shots before barrel relining.
The 10 m bigger blast radius, and the better ship killing power is valuable on an expensive battleship. On land, yes, build 2 128’s for the price of 1 150 mm.
 
Chapter 36: Post-AGN agreement expansion.
Chapter 36: Post-AGN agreement expansion.

The AGN agreement stipulated that Germany at all times would maintain a navy at 35% of the Royal Navy except in submarines were the number was 45% and could be expanded to 100% with prior notification of the British government. The follow-on French decision to build beyond the London Naval treaty was a source of German consternation on the actual numbers, but Hitler valued the short term legitimacy it provided more. As he would tell Raeder, Germany should build what it wanted, maybe conceal and deceive for a while, and when it was time to go beyond, Hitler would find a pretext.

Thus it happened that Germany in the aftermath of the signing of the AGN commenced a building program up to the AGN limitations and announced the building of 3 battleships of 35000 tons, 2 carriers of 23000 tons, the upgrade of their existing panzerschiffe to capital ships (6 11 inch guns each) and the building of 6 heavy cruisers of 8300 tons. The Germans also now acknowledged that they had launched 6 destroyers of 2000 tons and were laying down 6 more and for submarines, that they were building 12 coastal submarines and 6 ocean going models. Germany had plenty of spare tonnage in light cruisers, but they were out of building capacity for the moment.
 
Chapter 37: German naval aviation influencing radar development and computation.
Chapter 37: German naval aviation influencing radar development and computation.

The Reichsmarine now named Kriegsmarine had practiced naval aviation in Odessa* since the early 1920’s and it was clear that naval aviation was both an unknown that might obstruct the strategies made for Germany’s capital ship raiders (could slow them down), a major force multiplier as scouts, and an offensive weapon. These realizations meant that Germany’s capital ships were the protected in AA artillery, and an independent school had been established for anti-aircraft gunnery, and Germany were establishing their own carriers. Even so, the Kriegsmarine realized the danger from surprise air attacks and the independent administration regarding air defense was to play an important role in the early 1930’s. The department of naval anti-aircraft defense would in 1930 attract physicist Rudolf Kühnhold who previous had worked on microwave communication systems. With a strategic development sponsor in hand, Rudolf Kühnhold established Gesellschaft für Elektroakustische und Mechanische Apparate (GEMA) in 1930**. GEMA would subsequently employ Hans Hollmann and Theodor Schultes from the Heinrich Hertz Institute in Berlin as consultants. GEMA would have strategic focus on early warning and range finding for naval artillery and especially aircrafts. The focus on the much higher precision needed for directing AA gun-laying stimulated continuous work on the cavity magnetron and progress in this regard fueled development of more powerful and smaller computation devices. At the end of the 1930’s, the naval focus on both gun-laying and code-breaking would have made Germany the world leaders in analog and electronic computation.


*Cf chapters 24 and 28.

**Established in 1934 IOTL
 
Chapter 38: German naval aviation and aircraft development.
Chapter 38: German naval aviation and aircraft development.

The two converted freighters did not serve long on the South Atlantic mailing routes before they returned to Germany as dedicated training ships for the new Kriegsmarine. On these the logistics of navigation, steam and compressed air driven catapults and working arrestor hooks and caples, and provided valuable experience before constructing the first two purpose built fleet carriers and finishing the design work on the converted liners. It also taught the Germans the hazards of carrier landings and take-off and would be instrumental in the future procurements. The German doctrine on carrier aviation was not very clear as it was gradually dawning on the Germans that carrier borne torpedoes and AP bombs would be a threat to larger ships, while the Germans maintained a fixed fast battleship/battlecruiser based strategy for winning the future commerce war. Initially, and following this strategy, defense of the battlegroups and scouting came first, while offensive strike power came second. Based on the continuous operation out of Odessa and ocean operations from 1934 (with mail planes), the Kriegsmarine had formed a separate entity, The Marineflieger, with a limited, but existing capacity to order its own aircraft. Its first ambition had been to order an interim trainer and then a follow-on advanced torpedo, dive, scout plane which would later turn into the Fi-167. The Marineflieger leaders also realized that cutting edge fighter aircraft would be hard to establish from scratch just for small volumes, and was therefore present as observers when the results of the Luftwaffe call for a fighter aircraft were tested in Rechlin, the Raubvogle immediately favored the He-112A.

The He-112A nevertheless lost the competition to the Bf109, but Ernst Heinkel were nevertheless guaranteed production orders for the Raubvogle of either the He-112A or the He-112B redesign that Heinkel had also been asked to make for the competition. The order for Heinkel aircraft let to interference from the German ministry of aviation who were wary of distractions to the Heinkel manufacturing capacity and expected it to be dedicated to producing bomber aircraft when it seemed Heinkel would lose the fighter order.

Prompted by this impressive capability of the Air Ministry to provide obstacles, and the observation that engine supply had limited the test of the first fighter aircraft*, the Raubvogle department awarded a separate contract for both Heinkel and for a joint venture between MAN and Daimler-Benz to build a navy operated airframe and aircraft engine factory.



*OTL the first German fighters were tested with Rolls-Royce engines.
 
Last edited:
Chapter 38: German naval aviation and aircraft development.

The two converted freighters did not serve long on the South Atlantic mailing routes before they returned to Germany as dedicated training ships for the new Kriegsmarine. On these the logistics of navigation, steam and compressed air driven catapults and working arrestor hooks and caples, and provided valuable experience before constructing the first two purpose built fleet carriers and finishing the design work on the converted liners. It also taught the Germans the hazards of carrier landings and take-off and would be instrumental in the future procurements. The German doctrine on carrier aviation was not very clear as it was gradually dawning on the Germans that carrier borne torpedoes and AP bombs would be a threat to larger ships, while the Germans maintained a fixed fast battleship/battlecruiser based strategy for winning the future commerce war. Initially, and following this strategy, defense of the battlegroups and scouting came first, while offensive strike power came second. Based on the continuous operation out of Odessa and ocean operations from 1934 (with mail planes), the Kriegsmarine had formed a separate entity, The Marinevogle, with a limited, but existing capacity to order its own aircraft. Its first ambition had been to order an interim trainer and then a follow-on advanced torpedo, dive, scout plane which would later turn into the Fi-167. The Marinevogle leaders also realized that cutting edge fighter aircraft would be hard to establish from scratch just for small volumes, and was therefore present as observers when the results of the Luftwaffe call for a fighter aircraft were tested in Rechlin, the Raubvogle immediately favored the He-112A.

The He-112A nevertheless lost the competition to the Bf109, but Ernst Heinkel were nevertheless guaranteed production orders for the Raubvogle of either the He-112A or the He-112B redesign that Heinkel had also been asked to make for the competition. The order for Heinkel aircraft let to interference from the German ministry of aviation who were wary of distractions to the Heinkel manufacturing capacity and expected it to be dedicated to producing bomber aircraft when it seemed Heinkel would lose the fighter order.

Prompted by this impressive capability of the Air Ministry to provide obstacles, and the observation that engine supply had limited the test of the first fighter aircraft*, the Raubvogle department awarded a separate contract for both Heinkel and for a joint venture between MAN and Daimler-Benz to build a navy operated airframe and aircraft engine factory.



*OTL the first German fighters were tested with Rolls-Royce engines.

It would be "Seevoegel" in German for a alias name in disguise, or "Marineflieger" as name for an official branch of the Kriegsmarine.
 
Chapter 37: The German naval expansion plan and TL.

The discussion between Raeder and Hitler had revolved into an understanding by Raeder of Hitler’s plans of increasingly calculated risks. Until 1935, Hitler and the navy had understated the risk Germany posted, following 1935, when the AGN was announced Hitler had wanted to appear safe from a British perspective and more than a pushover for France. That Hitler had succeeded so far was clear when German troops moved into the previously demilitarized Rhineland.

The next task was for the German army to expand, so that it in reality was not a pushover, because Hitler wanted to increase the stakes by dismantling the alliances and understandings of Status Quo that was aligned against Germany. The alignment between Benito Mussolini and Hitler was perhaps the most important of these changes and followed international embargoes against Italy when they declared war against Ethiopia.

Hitler would now consolidate the rearmaments process that was currently threatened by a steel crisis, and Raeder’s job was to rebuild the navy in the interim. In making the naval rearmament, the Kriegsmarine had to walk a precarious balance with the British and the Royal Navy. To maintain the illusion of abiding to the AGN agreement, and only break the illusion when the Kriegsmarine had already acquired the strength to act as a deterrent.

The naval rearmament managed to navigate the steel crisis in an unconventional fashion, as it directly acquired iron and processed steel from abroad in return for selling of merchant ships. The downside of this was that some activity had to be postponed.

Here follows an overview of what the German possessed and had in the making in the summer of 1936:

Floating:

12 800 tons motortorpedoboats

12 coastal submarines

12 E-boats

6 modern light cruisers

2 converted transports acting as carriers (these were unarmed, and not officially marine ships)

6 Panzerschiffe officially at 10000 tons. The wo newest ones were launched with 3x2 11’’ guns, two had been upgraded and were indergoing sea trials, two were in drydock and were being upgraded.

6 heavy cruisers. These had all been launched and equipped with the 3x8’’ inch turrets from the first 4 of the Panzer shiffe. All 6 were still fitting out with the last expecting commission in 1937.

6 Diesel Destroyers armed with 4x 150 mm DP guns, long range, 8 torpedo launchers and a good complement of AA guns.

Non-comissioned civilian ships designed for later conversion:

4 major liners (2 at 50000 tons, 2 at 60000 tons), 3 smaller liners at 25000 tons designed for carrier conversions.

6 fleet support ships that currently served as transports.

On the slipways:

Germany had 5-6 (depending on whether we include ships build in Bremen for which the draught of the Bismarck class battleships are at the limits) for battleships and carrier sized ships. These were engaged in:

3 officially 35000 tons battleships to be armed with 3x3 14 inch guns (unofficially 45000+ and 3x2 420 mm guns) laid down in 1935 and expecting launch in late 1937-early 1938*

2 23000 tons carriers also laid down in 1935 and expecting launch in mid-1937*

All smaller slipways were also active:

6 E-boats (the yards were to build these as fast as possible and would evolve in construction time from 6 months to 3 months over the coming years)

6 2600 tons Destroyers were building in Hamborg, Kiel and Bremen.

6 ocean going submarines and a further 12 coastal submarines were building in Wilhelmshafen and Kiel. 6 further slipways were being made for ocean going submarines.

In 1936 6 further slipways capable of building light cruiser sized vessels were taken up by civilian construction. In the mean time, the equipment, guns and machinery had been order for a further 12 light cruisers. 6 to be laid down in 1937, 6 in late 1938.

2 slipways were being established to build larger ships. These would serve orders for the large fleet support ships to be made in 1937, 1938 and possibly 2 in 1939.



With this level of activity, it was possible for the Kriegsmarine to lay down shipping in excess of the AGN in 1937, but the heavy ships were not likely to commission until 1938-9. This had the potential to generate a threat before the build-up of a deterrent, a conundrum that could not be solved easily unless at the risk of confrontation. Currently, the policy would be to order engines and guns in advance, but this could not entirely solve the problem.

*Based on OTL Bismarck and Graf Zeppelin timelines from laying down to launch.
 
Chapter 38: Shipbuilding activities of 1937

Following the launch of 2 fleet carriers and the first battleship, the Kriegsmarine now had the first opportunity to build blatantly beyond the AGN agreement. Hitler decided the time was not yet opportune and the spare capacity was used for fleet support ships. The Kriegsmarine did however initiate construction of a new battleship and a conversion of a liner into a carrier. These developments would would for a while give the impression that the Germans intended to abide to the AGN and the decision to convert a liner rather than construct a new fleet carrier was seen as a sign that resources were not spend without limits. In fact, this decision had been chosen to gain experience and thus ensure a more swift conversion at a later time of the 4 major and 2 smaller liners still awaiting conversion.

The status of the Kriegsmarine expansion with regards to modern units as of end of 1937 were as follows:

12 800 tons motortorpedoboats

6 Ocean going submarines

24 coastal submarines

24 E-boats

6 modern light cruisers

6 Panzerschiffe officially at 10000 tons and equipped with 3x2 11’’ guns

6 heavy cruisers equipped with the 2x3x8’’ inch turrets from the first 4 of the Panzer shiffe.

12 Diesel Destroyers armed with 4x 150 mm DP guns, long range, 8 torpedo launchers and a good complement of AA guns.

Non-comissioned civilian ships designed for later conversion:

4 major liners (2 at 50000 tons, 2 at 60000 tons), 2 smaller liners at 25000 tons designed for carrier conversions (one less than the year before, now under conversion).

6 fleet support ships that currently served as transports.

Fitting out:

2 fleet carriers, the Bismarck battleship

On the slipways:

Following the launch of Bismarck, Peter Strasser and Graf Zeppelin (1BB, 2CV), only two of the first 3 officially 35000 tons battleships were still on the slipways.

Following the laying down of Duke of York and the American invocation of the escalator clause, the Germans had initiated the construction of a new class of officially 45000 tons battleship armed with 4x2 406 mm guns with a 5000 tons heavier displacement (thus 10000 tons over the 45000 tons allowed).

Likewise, following the laying down of HMS Formidable, the German had initiated the conversion of the 25000 ton liner Scharnhorst into a “small fleet carrier”. This was ongoing in a drydock in Wilhelmshaven.

All smaller slipways were also active:

6 E-boats (the yards were to build these as fast as possible and would evolve in construction time from 6 months to 3 months over the coming years)

6 2700 tons diesel Destroyers were building in Hamborg, Kiel and Bremen.

12 ocean going submarines and a further 12 coastal submarines were building in Wilhelmshafen and Kiel. A further 6 slipways were under construction.

6 light cruisers laid down in 1937

5 large fleet support ships (officially transports, 3 now using cleared battleship capable slipways).
 
Following the laying down of Duke of York and the American invocation of the escalator clause, the Germans had initiated the construction of a new class of officially 45000 tons battleship armed with 4x2 406 mm guns with a 5000 tons heavier displacement (thus 10000 tons over the 45000 tons allowed).

It would be better to have 42 cm guns like the 35k ton battlecruisers.
 
Top