Better German naval strategy 1930-1945?

[z42]

I recall reading somewhere (Wikipedia maybe?) that German naval strategy in the run up to the war as one characterized by "strategic confusion". An apt description, perhaps.

So what would be a better strategy, and what hardware should they have built instead of the historical one to support that?

For a very brief background, the Versailles treaty limited Germany to 6 light cruisers of up to 6000 tons and 6" guns, and 6 maximum 10000 ton ships to replace the 6 pre dreadnoughts they were allowed to keep after WWI. Furthermore the Allied Control Commission apparently allowed Germany to manufacture at most one gun larger than 28cm per year, effectively limiting the ships to that. These limitations resulted in the Königsberg class light cruisers and the Deutschland class armored ships / heavy cruisers / pocket battleships / however you wish to classify them.

Germany wasn't part of the Washington and London naval treaties, though via the 1935 Anglo-German naval treaty they effectively were, as that limited Germany to 35% of the RN for every class of ships (with the classes defined as in the Washington / London treaties).

So, what should Germany have done?

A slightly related thread, we discussed building CV's instead of gun equipped capital ships in Germany forgoes battleships, goes all in on CVs

 

[z42]

For some unorganized thoughts by yours truly:

Strategically, UK would make sure to outbuild Germany. The outcome of Jutland 2.0 would have been a forgone conclusion. The only way the German navy would be able to threaten the UK would be by hitting commerce ("kreuzerkrieg"). So in a way the 1935 Anglo-German treaty (AGNT) suckered Germany into building a miniature copy of the RN, which would be easily beatable in a Jutland 2.0 and less dangerous than a navy optimized for Kreuzerkrieg.

About the same time as the AGNT Germany flipped the bird at the Versailles land and air restrictions, so I'm not sure had they done the same to the naval restrictions the reactions would have been particularly different?

So, Kreuzerkrieg it is. What kind of ships to build for that?

• Subs and the auxiliary cruisers (hilfkreuzer) were fairly successful, particularly earlier in the war, so build more of those.
• Evidently the big lead smelter required for submarine batteries was a bottleneck, so probably not feasible to start massively expanding sub production sooner?
• For auxiliary cruisers, should be possible to require some civilian transports and liners to be built with conversion in mind. This should allow getting more of them into service relatively quickly.
• As discussed in the CV thread, hard to see a role for them.
• Some gun equipped big ships are probably useful, for stuff like the Norway invasion, and as a kind of fleet in being, forcing the Allies to dedicate capital ships for convoy escort duty, as well as keeping heavy units in home waters in case the Germans try something.

As for those capital ships:

• Needs to be able to beat a treaty cruiser, to force the Allies to employ their own capital ships.
• Full battleships are perhaps a bridge too far, in the sense the Allies can always build more of them?
• But if not able to beat a battleship, need to be able to run away. So needs to be very fast, say 32 knots at least?
• So maybe something like a pocket battleship 2.0, with more speed and sufficient armor so the citadel is resistant to 8" fire?
• The 28cm guns are probably suitable, if for no other reason they already exist.
• Maybe double down on diesel power rather than giving up after the PBB's? The pivot to high pressure steam wasn't exactly happy. And while the PBB power plants had worse power to weight than contemporary steam turbine plants, there was a lot of runway in diesel technology. Despite the drop in diesel funding after the steam pivot, by 1939 MAN had developed V24 diesel engines with much improved power to weight. MAN Double-Acting Diesel Marine Engines Of course, in retrospect we can say that double acting internal combustion engines were a mistake, oh well.
• One thing the Germans missed was DP secondaries. Say the 5" gun they had on some destroyers could have been developed into one. Oh, and don't put 6" guns on destroyers, too top heavy.
• What's up with the German fascination with 3 shaft designs, when practically everyone else was using 4. This article History and Technology - Shafting a Ship - NavWeaps doesn't think particularly highly of them.
• Maybe a contemporary all or nothing armor scheme rather than the turtleback scheme the German heavies historically had?

 

[EwenS]

35% except for submarines. See para 2f. Limit was 100% of British & Commonwealth tonnage, BUT Germany agreed to restrict that to 45% (unless it felt it necessary to exceed 45% for some reason). But that increase had to be accommodated within the overall 35% limit i.e there had to be a trade-off in another category.

World War Two Ships: 1935 Anglo-German Naval Agreement

Re carriers, the tonnage allowed to Britain under the 1922 WNT was 135,000 tons with a max of 27,000 tons per ship. From 1 Jan 1937 there was no overall tonnage limit, just a limit of 23,000 tons per ship.

So in 1935 Germany's carrier tonnage would be limited to 47,250 tons. That was a driving factor in the design of the Graf Zeppelin.

 

[EwenS]

Incidentally, Stuart Slade's final sentence about triple shafts and the Implacable Class is incorrect.

"When the treaty limits were lifted, the British redesigned their carriers (Indefatigable and Implacable) with a conventional four shaft layout."

The Implacable design was produced in early 1938 when the Treaty limits were still in place. The Admiralty wanted more speed than an Illustrious for undefined reasons. The advice from the EinC at the Admiralty was that this couldn't be done by forcing the machinery designed for the Illustrious, and that a 4 shaft set-up would be required to cope with the increased power requirement. Implacable was laid down in Feb 1939.

See Friedman's "British Carrier Aviation" for the design history of these ships.

 

[Shortround6]

Some interesting questions, a lot of times the details are the problems.

So, Kreuzerkrieg it is. What kind of ships to build for that?

• Subs and the auxiliary cruisers (hilfkreuzer) were fairly successful, particularly earlier in the war, so build more of those.
• Evidently the big lead smelter required for submarine batteries was a bottleneck, so probably not feasible to start massively expanding sub production sooner?
• For auxiliary cruisers, should be possible to require some civilian transports and liners to be built with conversion in mind. This should allow getting more of them into service relatively quickly.
• As discussed in the CV thread, hard to see a role for them.
• Some gun equipped big ships are probably useful, for stuff like the Norway invasion, and as a kind of fleet in being, forcing the Allies to dedicate capital ships for convoy escort duty, as well as keeping heavy units in home waters in case the Germans try something.

The Auxiliary cruiser thing turned out to be not so great. It can be traced back through centuries of sail. But Technology screwed thing up pretty quick. An Auxiliary cruiser can fight a another Auxiliary cruiser fairly evenly, assuming like to like armament. However they are both egg shells armed with hammers. Merchant ships have machinery that extends well above the waterline making it very vulnerable to hits. There is no armor on the hulls or decks, even splinter proof.
A number of ships had been built with reinforced deck plating and or bulkheads for gun mounts. However this required single mounts for anything sizable and it required low angle guns, The higher the elevation the greater the recoil load put on the deck structure. Power mountings were also difficult to install. Ammunition supply was hard for the heavier guns (like 4.7in-6in). trying to run lines/cables for fire control added to conversion problems. As did trying to mount fire control equipment (range finders, gun directors) in places with good range of arcs.
Liners, even small ones, tended to be fairly thirsty and were designed for certain "runs" with fueling available at each end of the trip (mostly). Large fuel bunkers cut into cargo or passenger space on commercial ships.
The RN had an answer but they didn't build many, it does point out the differences.

All 6 main guns will point to the broadside, All main guns are in splinter poof gun houses with power elevation and traverse and enclosed ammunitions hoists. There is a main gun director and range finder over the Bridge and there is an auxiliary gun director and rangefinder just in back of the mainmast for redundancy. Note the lack of portholes amidships where the boiler rooms are. Not 6in shell proof but splinter and light gun proof. Better watertight subdivision.
Maybe an Auxiliary cruiser can beat one in a gun fight or perhaps you need two on one, but in 10 fights out of 10 even this size cruiser is going to come out on top a very large percentage of the time. Even a large Destroyer has got better fire control than most Aux Cruisers.

Germans could not seem to to keep more than two heavy/capital ships in Action at the same time. Once you have two capitol ship a 3rd doesn't add much unless you can sortie all of them at the same time and in the same area, other wise you invite defeat in detail.

• Needs to be able to beat a treaty cruiser, to force the Allies to employ their own capital ships.
• Full battleships are perhaps a bridge too far, in the sense the Allies can always build more of them?
• But if not able to beat a battleship, need to be able to run away. So needs to be very fast, say 32 knots at least?
• So maybe something like a pocket battleship 2.0, with more speed and sufficient armor so the citadel is resistant to 8" fire?
• The 28cm guns are probably suitable, if for no other reason they already exist.

Problem for the Germans was that for anything less than a capital ship the British were going to Graf Spee it. They were not going to go one on one with super cruiser. They were going to use 3-4 cruisers at the same time if there was no battle cruiser.
Highspeed and resistance to 8in shell fire both take more displacement than many people realize.
Graf Spee needed about 54,000hp to do 28kts, the Hippers needed 132,000hp to do 32 knts. You can similar bounces with the French and Italian cruisers
US 260lb 8in shells were rated at 4in at 23,600yds, 5in at 19,500yds and 6in 16,600yds. I don't have the figures for British 8in shells. Deck armor goes the other way. you want between 2 -3in depending on range.

Maybe double down on diesel power rather than giving up after the PBB's? The pivot to high pressure steam wasn't exactly happy. And while the PBB power plants had worse power to weight than contemporary steam turbine plants, there was a lot of runway in diesel technology. Despite the drop in diesel funding after the steam pivot, by 1939 MAN had developed V24 diesel engines with much improved power to weight. MAN Double-Acting Diesel Marine Engines Of course, in retrospect we can say that double acting internal combustion engines were a mistake, oh well.

Germans often seemed to be distracted by pretty toys. The British were sort of sticks in the mud, but they needed machinery that was going to work when it was several years old and 10s of thousands of miles away from England. The US split the difference with a lot more steam pressure and temp than the British but a lot less the Germans. They got better power to weight than the British and a lot more reliability than the Germans.

One thing the Germans missed was DP secondaries. Say the 5" gun they had on some destroyers could have been developed into one. Oh, and don't put 6" guns on destroyers, too top heavy.

German 5in wasn't a very good DP gun. It may have been that some other countries but it wasn't as good as the US 5"/38.
Most countries biased the secondary guns too much for surface fire. If you want good AA you can't just point the guns upward. You need guns that are light and easy to aim, you need good shell supply and you need gun barrels that are not going to shoot out their rifling in a few air attacks.

 

[Thumpalumpacus]

Without numbers, their strategic options seem limited, and easy to answer from the British POV.

 

[z42]

The Auxiliary cruiser thing turned out to be not so great.

I agree they were kind of crap. However, compared to a bespoke warship an auxiliary cruiser was very cheap, particularly considering that in peacetime it could be out there earning money rather than being an expensive paperweight.

And yes, once longer ranged patrol aircraft, better radios, radars etc became more common as the war progressed, it was basically game over for them. But until then, a pretty cost effective weapon to wreak some havoc.

Maybe an Auxiliary cruiser can beat one in a gun fight or perhaps you need two on one, but in 10 fights out of 10 even this size cruiser is going to come out on top a very large percentage of the time. Even a large Destroyer has got better fire control than most Aux Cruisers.

Something like Kormoran vs HMAS Sydney is certainly an aberration, and you'd expect a cruiser to rather easily handle such a situation.

Problem for the Germans was that for anything less than a capital ship the British were going to Graf Spee it. They were not going to go one on one with super cruiser. They were going to use 3-4 cruisers at the same time if there was no battle cruiser.

Yes, but this is true for pretty much anything Germany can build, including 40000 ton battleships. The RN would gang up on it with superior numbers. Hence why speed would be so important.

So in that sense there's nothing magical about a ship in the "capable of beating a treaty cruiser" size class, except that it's a kind of asymmetrical response to a navy that is constrained by the treaty system and can't afford to have real battleships lying around everywhere.

Highspeed and resistance to 8in shell fire both take more displacement than many people realize.
Graf Spee needed about 54,000hp to do 28kts, the Hippers needed 132,000hp to do 32 knts. You can similar bounces with the French and Italian cruisers
US 260lb 8in shells were rated at 4in at 23,600yds, 5in at 19,500yds and 6in 16,600yds. I don't have the figures for British 8in shells. Deck armor goes the other way. you want between 2 -3in depending on range.

Probably something like 20000 tons, or even more, depending on how optimistic you are wrt next gen diesels.

But yes, pushing past 30 knots tends to take exponentially higher engine power.

"Hull speed" is too simplistic for real naval architects, but gets the point across, to an extent.

Germans often seemed to be distracted by pretty toys. The British were sort of sticks in the mud, but they needed machinery that was going to work when it was several years old and 10s of thousands of miles away from England. The US split the difference with a lot more steam pressure and temp than the British but a lot less the Germans. They got better power to weight than the British and a lot more reliability than the Germans.

True.

A potential advantage of going with steam I didn't mention in the original post is the potential to use coal water slurry fuel, as discussed in this thread not too long ago German fuel situation and what to improve on it, 2.0 That is, use CWS for cruising and switch to fuel oil when max power is needed.

That being said, I do suspect they could have gotten diesel to work well enough had they stayed the course.

German 5in wasn't a very good DP gun. It may have been that some other countries but it wasn't as good as the US 5"/38.
Most countries biased the secondary guns too much for surface fire. If you want good AA you can't just point the guns upward. You need guns that are light and easy to aim, you need good shell supply and you need gun barrels that are not going to shoot out their rifling in a few air attacks.

Good points. The 5"/38 is probably the gold standard, so perhaps unreasonable to assume we get something better than that. But, something that is ready when these ships are built is needed if they are going to have an impact. No point fiddling with developing the ultimate DP gun and mount and have it ready in 1944.

Or as an alternative, use the existing 105mm heavy flak gun for surface targets as well (add a splinter proofed turret) and lose the 150mm secondaries the Germans historically had. That might have the opposite problem in that it's a bit weak for surface fire, but in retrospect I guess that might not be such a huge problem.

 

[Shortround6]

And yes, once longer ranged patrol aircraft, better radios, radars etc became more common as the war progressed, it was basically game over for them. But until then, a pretty cost effective weapon to wreak some havoc.

It turned out that there were not very many German commercial ships suitable for conversion to Aux cruisers. You need better than average speed but you need to be economical. You have to be sizable to store food and other supplies for long periods away from supply ships. You need suitable crew space. Finding ships that checked most of the boxes was difficult.
British AC had somewhat different requirements. They could be smaller, shorter ranged in general. Good economy was nice but not as critical. The Better British AC's often had most their upper works modified but then they weren't trying to disguise their conversion to warships.

So in that sense there's nothing magical about a ship in the "capable of beating a treaty cruiser" size class, except that it's a kind of asymmetrical response to a navy that is constrained by the treaty system and can't afford to have real battleships lying around everywhere.

If Germany had kept building Graf Spee's or built several new/improved versions I imagine the treaties would have gained some amendments/exceptions. The mid 1930s saw the whole treaty thing falling apart anyway. Good naval architects knew who was cheating and who was not. maybe you could skate by with 5-10% but they knew who was cheating by by 20-30% and that wasn't going to keep going on.

Or as an alternative, use the existing 105mm heavy flak gun for surface targets as well (add a splinter proofed turret) and lose the 150mm secondaries the Germans historically had. That might have the opposite problem in that it's a bit weak for surface fire, but in retrospect I guess that might not be such a huge problem.

Germans are in an interesting dilemma for commerce raiding. The 15cm guns are better for shooting up merchant ships with their much more destructive shells and the 15cm battery allows them to engage a 2nd or 3rd enemy warship (small) to try to push through an escort screen. Using 10.5cm guns for such work uses up a lot of shells. Where is the cross over point?
But the 15cm guns are useless for AA work, but that is with hindsight. A lot of money and effort was put into trying to make high angle 15cm guns in several navies. It took until the USS Worcester to get it to work.

Once you are down to the 8in cruiser and smaller then the 10.5cm guns make sense although again the Germans may have tried too hard for ballistic excellence. At sea on a moving ship the extra few thousand feet of altitude doesn't make much difference. Anything flying that high can't you except by accident.

 

[z42]

It turned out that there were not very many German commercial ships suitable for conversion to Aux cruisers. You need better than average speed but you need to be economical. You have to be sizable to store food and other supplies for long periods away from supply ships. You need suitable crew space. Finding ships that checked most of the boxes was difficult.

Hence the suggestion to partially fund the construction of such ships for commercial use.

If Germany had kept building Graf Spee's or built several new/improved versions I imagine the treaties would have gained some amendments/exceptions. The mid 1930s saw the whole treaty thing falling apart anyway.

Maybe. However, UK would likely still want to prioritize to build modern fast battleships to counter the Italians and Japanese rather than building dedicated "PBB2 killers".

Germans are in an interesting dilemma for commerce raiding. The 15cm guns are better for shooting up merchant ships with their much more destructive shells and the 15cm battery allows them to engage a 2nd or 3rd enemy warship (small) to try to push through an escort screen. Using 10.5cm guns for such work uses up a lot of shells. Where is the cross over point?
But the 15cm guns are useless for AA work, but that is with hindsight. A lot of money and effort was put into trying to make high angle 15cm guns in several navies. It took until the USS Worcester to get it to work.

Once you are down to the 8in cruiser and smaller then the 10.5cm guns make sense although again the Germans may have tried too hard for ballistic excellence. At sea on a moving ship the extra few thousand feet of altitude doesn't make much difference. Anything flying that high can't you except by accident.

Bigger bang delivered to a single address does have some advantages I think, however just by looking at weight of shells for installed weight the smaller gun might not be too bad. The 10.5cm twin mount was about 27 tons. Add some splinter and weather protection for the crew and we're probably looking at around 40 tons. For comparison the twin 5"/38 used on US cruisers was about 50 tons with heavier guns, so probably 40 is in the ballpark. Rof 15-18/min shooting 15 kg shells. So 12 kg shells/min/ton of turret.

The twin 15cm turrets used on German BB's was about 110 tons (though probably more armored than just splinter protection?). Rof 6-8/min, shooting 45 kg shells. So 5.7 kg shells/min/ton of turret.

 

[Shortround6]

Maybe. However, UK would likely still want to prioritize to build modern fast battleships to counter the Italians and Japanese rather than building dedicated "PBB2 killers".

It took the Germans 6 years to build the 3 Deutschland class ships. The British already had the Renown, Repulse and Hood and the French were building the Dunkerque and Strasbourg.
The Germans stopped building the originals. Had they continued by either speeding up building new ones or building larger (14,000-17,000 tons?) the British and French would have come up with something. And KGVs would have handled more of the original ones.

Bigger bang delivered to a single address does have some advantages I think, however just by looking at weight of shells for installed weight the smaller gun might not be too bad. The 10.5cm twin mount was about 27 tons. Add some splinter and weather protection for the crew and we're probably looking at around 40 tons. For comparison the twin 5"/38 used on US cruisers was about 50 tons with heavier guns, so probably 40 is in the ballpark. Rof 15-18/min shooting 15 kg shells. So 12 kg shells/min/ton of turret.

The twin 15cm turrets used on German BB's was about 110 tons (though probably more armored than just splinter protection?). Rof 6-8/min, shooting 45 kg shells. So 5.7 kg shells/min/ton of turret.

Yes the twin 15cm turrets had a lot of armor. 100-140mm depending on ship.
Not sure that the German 12.7cm guns could have replied well to the Ajax and Achilles although 4 guns to 8 is a mismatch to begin with.
10.5cm would have been out of luck even with a 4 twin mounts per side.

But the Germans often did not have the magazine capacity to back up the guns. Something that is often overlooked when looking at the US 5"/38, The US ships often started with 300rpg and quickly went to around 450rpg. They were not going to run out of ammo in 8-12 minutes of fast firing.

 

[z42]

Yes the twin 15cm turrets had a lot of armor. 100-140mm depending on ship.
Not sure that the German 12.7cm guns could have replied well to the Ajax and Achilles although 4 guns to 8 is a mismatch to begin with.
10.5cm would have been out of luck even with a 4 twin mounts per side.

But the Germans often did not have the magazine capacity to back up the guns. Something that is often overlooked when looking at the US 5"/38, The US ships often started with 300rpg and quickly went to around 450rpg. They were not going to run out of ammo in 8-12 minutes of fast firing.

The lighter DP secondaries would likely be unable to penetrate the citadels of light cruisers. However the Leanders had only 25mm turret armor, so even 10.5cm secondaries should be able to wreck them. So a hail of 10.5 cm shells would quickly mission kill it. Then again, a light cruiser would also be capable of mission killing a PBB as long as the PBB main guns are occupied elsewhere, and the UK would happily trade a mutual mission kill in the south Atlantic.

A fast "PBB2" would have the option to keep out of light battery range and rely on the main guns. However dispatching 3 cruisers at long range would run down the main battery magazines, so.. No magic solutions however you turn it.

 

[Shortround6]

The lighter DP secondaries would likely be unable to penetrate the citadels of light cruisers. However the Leanders had only 25mm turret armor, so even 10.5cm secondaries should be able to wreck them. So a hail of 10.5 cm shells would quickly mission kill it. Then again, a light cruiser would also be capable of mission killing a PBB as long as the PBB main guns are occupied elsewhere, and the UK would happily trade a mutual mission kill in the south Atlantic.

A fast "PBB2" would have the option to keep out of light battery range and rely on the main guns. However dispatching 3 cruisers at long range would run down the main battery magazines, so.. No magic solutions however you turn it.

Trouble is that the British had given up on the Leander design and laid down two Southampton's in 1934. Still with 25mm turret armor but hail of 6in shells is also going to put the 10.5cm batteries out of commission fairly quickly.

The 10.5cm guns do not have the effective range of larger guns, please forget about max range often listed. Once guns are elevated to around 20 degrees accuracy really starts going to pot. It may be even less, and a 6in gun has thousands of yds more range than a 10.5cm gun at the same elevation. This is the guns, fire control can make up some of the difference.
German 10.5cm AA guns had 19,400yd range at 45 degree lob.
British 6in modern cruiser guns had 20,000yds at 24.1 degrees.
They ranged to 15,000yds at 13.1 degrees. It took over 50% more time for the shells to make it to 20,000yds as it did to 15,000yds.

Commerce raiders have problems with limited ammo. A lot of ships didn't carry enough for WW II conditions. For any of their batteries, so sometimes (mostly?) they did not actually carry the full range of ammunition/shells available. For instance the Germans often did not carry 15cm APC ammo and had entirely, or almost so, HE ammo.
There was an AP round for the German 10.5cm but with 400-500 rounds per barrel it wasn't often carried. Having more AA rounds was generally preferred. Maybe they could trade the 15cm guns/ammo for more 10.5cm ammo?

Dispatching 3 cruisers by a single PBB2 was going to be a bit tricky or depend on luck. The Graf Spee fought one of the two weakest 8in cruiser the British had and 2 of the almost weakest modern 6in cruisers the British had. The PBB2 might run into a few EX WW I cruisers or it might run into 1/2 county class cruisers and 2/1 Town class.

Such was the pace of cruiser construction in the late 30s that Britain laid down 5 Fiji's in 1938 and two Dido's. From 1937 through 1939 the British laid down 26 light cruiser (15 Dido's and improved Dido's). It was WW I all over again, the Germans were not going to able to out build the British. Could the German commerce raiders keep a disproportionate number of ships busy looking for them?

 

[don4331]

PBB needed more aviation assets - at the very least more cylinder heads for the existing plane, preferably more airplanes.

AGS successfully avoided an encounter with HMS Cumberland as her Arado warned her of the danger. Had AGS been able to launch her floatplane on the fateful morning, Langsdorff would have beat tracks quick in opposite direction (Correctly identifying that he was up against a York class CA and 2 Leander class CLs, not an Arethusa class CL and 2 DDs might have also changed his opinion about engaging.)

Maximum firing rates are deceptive as well for surface targets - blazing away without knowing if you're on target is waste of ammunition. Fire, observe shot fall, correct, and fire again - which gets firing rate down to ~2 rounds/minute at "normal" surface ranges. AAA firing is different story - too much deviation between rounds if firing/observe/correct, but ranges are shorter too.

Fire control which only 6 people at ?Siemens? plant in Germany could assemble/calibrate might make for a wonderfully accurate system. But when it gets knocked in battle, people aboard ship need to be able to fix it.

 

[Shortround6]

Correctly identifying that he was up against a York class CA and 2 Leander class CLs, not an Arethusa class CL and 2 DDs might have also changed his opinion about engaging.)

Assumes that the German aircrew were a lot better at identifying ships than the American and Japanese aircrew were

Fire, observe shot fall, correct, and fire again - which gets firing rate down to ~2 rounds/minute at "normal" surface ranges.

Quite right.
The time of flight for the British 6in was
10,000yds...................15.9 sec
15,000yds...................29.4 sec
20,000yds...................47.2 sec
24,500yds...................71.4 sec

British 6in had a rate of fire of 6-8 rpm but the longer elevations required the guns to be lowered for hand ramming between shots and elevated to firing elevation
Might take 3 seconds to lower the guns and 3 seconds to elevate them depending on range.
And note that fire control at 24,500 yds in trying to figure out where the ship is going to be 71.4 seconds in future. A 30kt ship moves about 1100 meters in that time.

 

[z42]

Could the German commerce raiders keep a disproportionate number of ships busy looking for them?

That's really the central question a German naval strategy will have to answer, whether they build a fleet optimized for commerce raiding or a "balanced" treaty style fleet.

PBB needed more aviation assets - at the very least more cylinder heads for the existing plane, preferably more airplanes.

Extending that argument, what about baby CV's optimized for commerce raiding? That would allow better situational awareness that could lead to finding more targets to attack, as well as avoiding allied hunter groups. Of course there are some pretty major questions in such a scenario. E.g.

• Committing to that path after the OTL PBB's when it was far from clear naval aviation would develop into the fearsome weapon it becomes in WWII.
• Building up institutional experience on how to operate carrier aviation. Such as figuring out that silly trolley system was no good and replace it.
• The LW vs KM turf fights need to be resolved.
• Even if all the above is resolved, if ammunition supply is a problem for gun based commerce raiders, I can't imagine the situation being easier for providing sufficient aviation fuel, bombs (and/or torpedoes), spare parts etc. for the baby CV. At least in the Pacific war the fleet oilers were a critical factor in being able to sustain operations.

 

[Shortround6]

The real problem for the German raiders was the change in aviation in the few years before WW II and the first few years of WW II.

Sticking 2-3 more floatplanes on raider might have helped early on, although having the floatplane (or flying boat) get spotted as a German type is a sure signal that a German raider is within a few hundred miles.
The real problem came with proliferation of allied patrol bombers/aircraft and more bases as the war went on. There were fewer and fewer areas of ocean that the raiders could hide in.
A ship that sent out an SOS might be only a few hours or it might be over a day from a surface ship to investigate. A plane might be there in just a few hours.
They may not keep ships in convoy but most ships operated in trade lanes just a few hundred miles wide. A plane could cover quite an area assuming weather was good. Once spotted by air it is a lot harder for the raider to get lost again.
The Raider needs to "get lost" not shoot down a PBY which gives the allies a 'flaming datum' using a float fighter.

And light CVs just puts the Germans back into the naval race, trying to build light CVs faster than the British can build light CVs.

 

[Shortround6]

Even if all the above is resolved, if ammunition supply is a problem for gun based commerce raiders, I can't imagine the situation being easier for providing sufficient aviation fuel, bombs (and/or torpedoes), spare parts etc. for the baby CV. At least in the Pacific war the fleet oilers were a critical factor in being able to sustain operations.

The British were planning on having several light CVs when war broke out. Plans went to crap when they lost the Courageous and Glorious. The Hermes spent quite a bit of time in the South Atlantic and Indian Ocean as air support for convoys and anti-raider units. She wasn't much good (too small) for anything else.

From Wiki...............
"On 5 October, the British and French navies formed eight groups to hunt down Admiral Graf Spee in the South Atlantic. The British aircraft carriers HMS Hermes, Eagle, and Ark Royal, the French aircraft carrier Béarn," plus the battle cruisers (British and French) and 16 cruisers were committed.

The Courageous had already been lost.

Anything the Germans can build that can be seen building/converted in a German shipyard is going to provoke some sort of response from the British and/or French.
we can argue about if the response would work or be ready in time but the Germans are not going to expand their raiding force by much and have the British and French keep to historical building levels.

 

[z42]

Anything the Germans can build that can be seen building/converted in a German shipyard is going to provoke some sort of response from the British and/or French.
we can argue about if the response would work or be ready in time but the Germans are not going to expand their raiding force by much and have the British and French keep to historical building levels.

The UK had more shipbuilding capacity than the Germans, but it wasn't infinite either. What are they going to give up to respond to German light CV's? They were already pumping out ASW escorts to counter the threat of German u-boats (which was entirely the right thing to do), are they going to sacrifice the KGV's to build more CV's? If so, what is the counter to Italian and Japanese BB's?

In any case, I'm not sure what a workable time-line would be. It probably takes several years to work out a useful naval aviation capability even after you have a carrier and aircraft in place. If they start churning out CV's instead of the Scharnhorsts, Hippers and Bismarcks, the first ones will be ready just before the outbreak of the war. Probably they need to do something like converting a liner to have something to experiment with sooner.

 

[EwenS]

And all those carriers count against the German tonnage limit of 47,250 tons standard displacement. That is why only GZ and a sister were planned pre-war.

Pre-war the RN and USN looked at liner conversions of c20,000 tons and 20 knots. Even a cheap and cheerful Bogue class CVE was c8,000 tons with a speed of 18 knots.

When the Germans looked at liner conversions in WW2 it included the SS Europa (c45,000 tons 27 knots).

Grossly exceeding that 47,250 ton limit destroys AGNA 1935. It is one thing to build ships a few thousand tons over agreed limits, another to build multiple ships of 20,000 tons or more. For raiding in the Atlantic and IO something bigger than a WW2 escort carrier would be required. Hitler was keen to keep Britain onside for as long as possible.

 

[Denniss]

Swarms of subs with properly tested torpedoes would have been way more useful than big naval ships in the early war years. So build way more Type VII and IX instead of Bismarck/Tirpitz and the carrier(s).