How can a "better" Kriegsmarine be built?

[Dilandu]

Zepellin won't be ready until mid-to-late 1941, even in very optimistic circumstances; more likely later than that. Carrier has to operate as a coherent unit (even with a certain generosity of mind giving a discount to the significant surface firepower of this ship).

Exactly. That's why I consider all those ideas "Germany JUST NEED TO BUILD CARRIERS from 1936" to be... doubtftul at best. By the time of war, they would still be grasping the basics of carrier operations.

 

[Ainen]

Exactly. That's why I consider all those ideas "Germany JUST NEED TO BUILD CARRIERS from 1936" to be... doubtftul at best. By the time of war, they would still be grasping the basics of carrier operations.

Admiral Graf Zepellin in our lifetime was laid down on ... 28 December 1936. There's no change in timeline. It couldn't be started earlier, Gneisenau was juuuust launched from the same dock on December 8th.
By the time she was killed by Raeder in 1940 (due to the need to fortify Norway ASAP), she wasn't finished, and some carrier equipment still wasn't delivered (i.e. she couldn't be finished yet). Later it indeed arrived, but in any case, the ship won't start trials until summer 1940.

Then there will be a training cycle for the crew, several months long, and it can't be expedited. Then we(they) start the airwing learning process on the ship (first ever for them), and only after that can they (probably in summer 1941 in the western Baltics), do some evolutions and get a mini-CSG (carrier and a couple heavy cruisers...probably with rushed Seydlitz).

Or, throw her as is with Tirpitz on a sortie into the Atlantic, hoping Tirpitz and her own 5.9" guns will manage somehow.

 

[tomo pauk]

Once again, keep in mind that in 1940 there were very few naval Bofors operational anywhere. Mostly a few Dutch runaway ships (many - with half-experimental mountings), neutral Swedish ships...and that's it.

Germany was 1st in many things wrt. military tech. Going 1st with 37-40mm automatics would not be out of ordinary.

 

[Rule of cool]

IIRC the invasion of Norway was the Navy's baby. They certainly counted the Norway under Germany a boon.

Yes, you're right.

Brushing up on the history the Navy pushed for Norway invasion and successfully lobbied Hitler to have naval objectives included in the early planning for 1939 Fall Gleb specifically to fight Britain. After the Mechelen incident of 10 Jan 1940, the Navy started thinking on more grandiose lines, however they did not insist on naval objectives in the 'Manstien plan' as their (limited) objectives remained locked in from 1939 Fall Gleb.

A few things stand out to me from this.
Firstly, the Navy has learned their lesson from WW1 that breaking out of their geography was highly important and when war loomed, they were successful at getting naval aims recognised and included in Army/national planning.
Arising from this it is reasonable to structure a pre-war fleet building programme around the assumption that at least to an extent they weren't going to be constrained by peacetime geography, they can build to a more expansive plan.
Thirdly, while the Navy began to think more broadly in 1940 when the plans changed, they didn't aim to secure huge (to the point of unimaginable) naval objectives, the remained fixed on Norway and the Low Countries.

As a result, I think planning purely for a North and Baltic Sea Fleet is short sighted, it is perfectly reasonable for the pre-war Navy to build a fleet able to access the Channel and 'high' North Atlantic. However, it is unreasonable for the interwar navy to build a fleet for the 'central' Atlantic war as the Navy didn't even start thinking along those lines until forced to in 1940, didn't insist on 'central' Atlantic objectives and was surprised that they got the geography they did.

How does Plan Z meet the requirements of a North and Baltic Sea, Channel and 'high' North Atlantic Fleet?

 

[Ainen]

Germany was 1st in many things wrt. military tech. Going 1st with 37-40mm automatics would not be out of ordinary.

In theory, yes, but you'll need to move around weapon development cycles. It has to begin a couple of years later.
Sk c/30 wasn't some sort of outlier, after all; she was absolutely similar to, say, CAIL Mle 1933.

If it was a 1936 weapon, it probably could've ended up automatic. But how good? It depends. For example, Italy was ahead of its time with early automatics. But being automatic doesn't mean you're a Bofors, and Italian ships and even entire squadrons with multiple 37mm guns were screrwed on multiple occasions by Swordfishes in broad daylight - something that sk c/30 rarely allowed (it only really failed on Bismarck, but in very difficult conditions).

 

[builder396]

The ammo update for the 37mm Flak would've been one of the ways to improve it. The BK 3,7, that started as a spin-off from the Flak, ended up firing the ammo with 260g of propellant, vs. the Flak's 185g. Several other ammo types were being designed for the Flak, with 200 to 220g of propellant, so there is a lot of elbow room there.

Bugger that you bring that up, because Im pretty sure that was only for the APCR round, which is lighter and thus barrel pressure even with more propellant doesnt necessarily become excessive. Unfortunately APCR is pretty useless on a ship. You could go for a really light HE round, but then you traded in your range for shell velocity.

 

[Dilandu]

How does Plan Z meet the requirements of a North and Baltic Sea, Channel and 'high' North Atlantic Fleet?

Barely.

 

[tomo pauk]

If it was a 1936 weapon, it probably could've ended up automatic. But how good? It depends. For example, Italy was ahead of its time with early automatics. But being automatic doesn't mean you're a Bofors, and Italian ships and even entire squadrons with multiple 37mm guns were screrwed on multiple occasions by Swordfishes in broad daylight - something that sk c/30 rarely allowed (it only really failed on Bismarck, but in very difficult conditions).

Same as Germans, Italians also needed carrier vessels. Even if only to keep the enemy snoopers away, and to provide the 1st layer of air defense, the heavier guns being the second layer, and guns of 40mm and under the 3rd layer.

Bugger that you bring that up, because Im pretty sure that was only for the APCR round, which is lighter and thus barrel pressure even with more propellant doesnt necessarily become excessive. Unfortunately APCR is pretty useless on a ship. You could go for a really light HE round, but then you traded in your range for shell velocity.

260g for the APCR, max pressure of 2600 at. The normal pressure seem to be 2400 at, at least it is listed for the Mine shell (that was a rarity on the 37mm). 200g was for the incendiary & explosive shell (644g) with shortened tracer for 820 m/s, while there was also the Mine shell (550g) for the BK 3,7 with 220g of propellant, for 914 m/s.
Mine shell should probably grow in length and be at about 600g, and coupled with 200g it should still be both fast and rangy.

Granted, going with 37mm automatic that uses the ammo from the single-shot 37mm will see a major increase in ballistics here.

 

[T. A. Gardner]

IIRC the invasion of Norway was the Navy's baby. They certainly counted the Norway under Germany a boon.

The invasion of Norway was a disaster for the KM. They lost most of their surface fleet either sunk or damaged as a result of it. For the Luftwaffe it contributed heavily to the pilot shortage they had during the French campaign and then the BoB. Pilots in training and their instructors were heavily used to fly transport missions to Norway.

As an interesting aside here, the RN lost the HMS Glorious in a surface action against the Scharnhorst and Gneisenau. This marks the only time a carrier was sunk by battleship fire in a surface action. That loss can be almost entirely attributed to the incompetent command of Glorious by Captain Guy D'Oyly-Hughes. Hughes' views on carriers and air defense were very much in line with the pre-war Admiralty. That is, he felt that the primary air defense of a ship was the AA battery, so he ignored the advice of the FAA officers aboard and didn't order a standing CAP or even a ready CAP on deck. Planes were kept in the hanger for use in offensive strikes.

That resulted in the Glorious being surprised by the German battleships which made short work of it.

 

[T. A. Gardner]

I am sorry to ask, but you're an American, aren't you?
It's honestly an impressive level of ignorance of European geography.
In real life, French destroyers raided Skagerrak at least once. And no, they weren't sunk.

A one-off destroyer raid really shows nothing.

Real German carriers were laid down in late 1936 and 1938, respectively. Earlier L/D is impossible per your conditions.
As you know, even the unit laid down in 1936 wasn't finished. Here goes your entire revolution.

Yes, they were. They were in competition for construction capacity with battleships that take far longer to complete. Here, the battleships are not built. Building a single carrier starting in 1936 would take about 24 months to complete. If we assume another is completed every 12 months thereafter, that's 4 by 1940.

There's a reason Churchill (and RN) were so shocked after the Japanese raid into the Indian Ocean. RN combatants were under German air attacks on many occasions, and despite rather sorry state of RN air defenses and dozens of losses, this was not their experience.
British air threat was generally lower; German AAA and early war coastal air screens were generally better. Which is why, in the end, only one ship was disabled at sea, in very specific conditions.

The Luftwaffe was a poor measure to use. Luftwaffe pilots had little or no experience attacking naval targets underway. The IJN pilots on the other hand were very skilled at this. RN losses off Crete were significant, and even if many of the ships were only heavily damaged, they were still out of the war for months on end. On the other hand, RN AA defenses proved to have little deterrent effect and didn't shoot down that many aircraft.
The RN also didn't practice using effective formations for air defense relying instead on every ship maneuvering to avoid attacks and firing at attacking aircraft on their own.

 

[Rule of cool]

Barely.

Fair enough, but looking at Plan Z through such a set of requirements it doesn't look outlandish compared to a purely North and Baltic Sea Navy or one holding the entire Norwegian and French coasts.