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Hoi4 Dev Diary - Naval Treaties and Ship Refits

Hello, and welcome back to another exciting dev diary about ship design!

As many of you noted last week, ship design in the interwar years was heavily restricted by the Washington Naval Treaty and the First London Naval Treaty. During and after the Great War, naval planners the world over were drawing up plans for new battleships that made use of new technologies, with ever bigger guns requiring ever stronger armor meaning increasingly large ships that were becoming even more expensive. At the same time, Britain and France were at the edge of bankruptcy from the debts they had accumulated during the Great War and could not afford another naval arms race with the fairly untouched nations of Japan and the US.

The result was the Washington Naval Treaty of 1922, which forbade any new battleship construction for a period of 10 years and restricted the maximum size of ships as well as their gun armament. In 1930, the signatories of the Washington Naval Treaty came together and negotiated the London Naval Treaty, which limited the construction of cruisers and stipulated strict restrictions on their size. In early 1936, the London Naval Treaty was up for renegotiation and that, as they say, was when the trouble started.

These restrictions forced the designers of warships in the interwar period to come up with some interesting compromises, and although we can’t possibly model all the interconnected ways in which these restrictions impact design - the Nelson class baffled American designers who were trying to comprehend why the British would build a ship like that - we did want to model some of the impact and also represent the diplomatic effects of the naval treaties.

picture_naval_treaty.jpg


All the signatories of the 1930 London Naval Treaty will start with a national spirit that restricts the maximum cost of their capital ships. As I said last week, we originally played around a bit with tonnage as a restricting value for ship design, and obviously this would have tied in neatly with the Naval treaties, but the design was changed later to instead focus on slots and construction cost. We also thought about simulating the restrictions in gun caliber etc. through restricting modules, but in the end decided against it because it would disincentivize the player to engage with the ship designer - imagine researching a new heavy battery and then finding out that you can’t install it because it would violate the treaty! It still means that in ship design, you can’t just build the best possible ship on day one as the cost restrictions are quite harsh.

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When you start the game in 1936, you will notice a mission ticking down reminding you that the Second London Naval Conference is currently underway. If you don’t decide to bail, you will automatically sign the Second London Naval Treaty. Bailing from the treaty is at first only available during the London Conference, costs some political power, but less for fascist nations. However, fascist nations can stay in the treaty and later decide to cheat use creative accounting to measure the true displacement of their ships, which means they have reduced restrictions while, presumably, lying through their teeth when asked about the curiously large cruisers they are building (the Head of Ship Design for the Royal Navy during the 1930s once remarked that the other side was either building their ships from cardboard or lying when presented with the official numbers for a new cruiser!).

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Once world tension hits a certain level, the decisions to leave the treaty are once again available for everyone. Should any country have left the treaty, either during the initial conference or afterwards, a timer starts ticking down for the remaining countries that activates the historical “escalator clause”, which will ease the restrictions slightly, allowing even the signatories of the treaty to build more powerful ships. As a fascist country you therefore have an incentive to stay in the treaty, as it will restrict your opponents more than it restricts you while denying them the escalator clause.
escalator_clause_2.jpg

If a country outside the treaty reaches a certain percentage of the British size in capital ships, they can be invited into the treaty. Should the nation decline and continue to expand their navy until near parity, the treaty nations can try to force them to disarm up to 80% of the number of capital ships. A refusal to disarm may lead to war. If a signatory nation exceeds the allocated amount of capital ships, they immediately get a mission to reduce the number of capital ships, at the threat of major stability loss.

So you will probably want to make sure you have the most capable ships you can as you are quite limited in numbers as well as size. One of the more annoying parts of the old variant system was that a capital ship might well be obsolete by the time it hit the waves, with no chance of ever being modernized. It made even less sense in the context of the ship designer, where the upgrades between the ship classes were supposed to be more gradual. Enter the refit feature, which will allow you to upgrade your ships and otherwise tailor them better to your needs as the situation changes - from upgrading the AA on your battleships to removing one of the torpedo sets on your destroyers to make room for more depth charges.
refit.jpg


All modules have a production cost, of course, but in addition they can (and usually do) have a conversion cost as well as a dismantling cost. The conversion cost determines how much it costs to, well, convert that module from another module. This means that it is usually cheaper to upgrade, say, Anti-Air from Level 1 to Level 2 than it is to rip out the rear turret and put some AA in there. There are some exceptions to this, mostly for historical immersion: upgrading the engines is a major effort that historically required very long yard times (you basically have to cut open the hull to get the old engines out and get the new engines in, then patch it up), so it is almost always not worth it (upgrading the engines on an old battleship gets you about 2 knots of speed at the cost of a modern light cruiser), but we wanted to give you the option. As a general rule, it is never cheaper to build a lower tier and then refit to something more modern.
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If there is no specific conversion cost scripted in, you have to pay the dismantling cost for the old module and the construction cost of the new module. Modders will be pleased to hear that you can script in dismantling resource costs so you can actually gain resources back from scrapping certain components.
C_class_refit.jpg

To refit a ship, you create a variant and then select the ship you want to refit, then order it to refit to that variant. The ship will detach to go to the nearest naval base and become an item in the production queue with a few special mechanics: because it is technically still on the map, it can be bombed and damaged, which reduces build progress. If the province it is in is overrun by the enemy, it will be captured and may end up serving your enemies.
c_class_carrier_refit.jpg

You usually can’t refit between ship hulls (so a 1936 destroyer can only be refit to other 1936 destroyer variants), but otherwise you have a lot of freedom on what you can refit into what and are only really restricted by cost (for historical examples, see the Japanese Mogami class becoming heavy cruisers after being built as light cruisers). A special case are carriers, where cruiser and battleship hulls can be converted into certain carrier hulls. These are generally not as capable as purpose-built carriers, but if you have some old ships lying around…
picture_carrier_conversion_finished.jpg

Lastly, some of you have noticed that one of the German ships we showed last week looked a little different. The Admiral Scheer is at game start the Pride of the Fleet for Germany, giving Germany a small (5%) war support bonus and the ship itself some bonuses to defense against critical hits (ahistoric in case of HMS Hood, certainly) and bonuses to experience gain. It also has some interesting synergy with admirals that have the Media Personality trait: they will gain bonuses when commanding a fleet with a Pride of the Fleet in it.
Germany_panzerschiff.jpg

Assigning a ship as Pride of the Fleet is free if you don’t have one already. Changing your Pride of the Fleet costs some political power (and presumably makes the crew of the old one very sad, you monster). You can only make a capital ship the Pride of the Fleet, and you should choose wisely - losing it gives a painful penalty to war support for a while.
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That’s all for today, remember to tune in at 1600 hours for our stream, when we will show off some gameplay for Mexico!

Rejected Titles:

With a large enough pocket, every battleship is a pocket battleship

The Italians actually were building their cruisers out of cardboard as it turned out

What really is a heavy cruiser, anyway?

Get your discount cruisers

You can now play with your LEGO-ships even after you have built them!

Personally I think armor is overrated anyway

The C-Class Carrier Conversion has nothing on the T-Type Torpedo Transformation or the M-Model Machinegun Makeover!
 
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The Lexington and her sister were profoundly potent Carriers. Their armour actually helped keep them in the fight as well whereas the Yorktowns were particularly vulnerable to dive bomber attacks. They also maintained the largest US Air Groups until the Midways came on line. Just because they were lost in the first half of the war does not detract from that.

Only Lexington was sunk, Saratoga survived her injuries.

They took on a substantially larger Japanese Carrier arm and held the line sufficiently for Hornet and Yorktown to relocate from the Atlantic.

I don't disagree that Lexington and her sister were capable ships, but what exactly is this referring to? Yorktown arrived in the Pacific in December 1941, and Hornet arrived in March 1942. The only carrier battle in which the Japanese possessed a substantially greater number of aircraft was in October at Santa Cruz, which neither Lexington or Saratoga participated in.
 
To save your researchers some time, for the US in 1936 it should be the famous battlecruiser USS Lexington, which had been re-converted back from a carrier in 1934.

Never came across this information before. I can't find any information on line about it being converted back in 1934. Would like to get a source on that.
 
Another question beside the one with the 3D Model on Page 4:

@Archangel85
With Man the Guns: Is it possible to make Carrier-Variants for example for the Messerschmitt Me 262 and other jet-driven aircraft? It may be not the best thread to post this question, but it comes in my mind with the possibility to build different sized Carrier Vessels now.
 
Never came across this information before. I can't find any information on line about it being converted back in 1934. Would like to get a source on that.
We were being sarcastic.

I asked @Archangel85 yesterday whether it would be possible to convert carriers (back) into battleship/battlecruiser hulls, as obviously many of them started life as such, and we know you'll be able to convert the other way. He said he'd look into it, and I really hope it is possible when MtG is released.

It was never done historically for obvious reasons, but that isn't to say the player shouldn't be able to.
 
Can you launch ships before they are fully complete, like with divisions, as was done with the Prince of Wales when she was sent to hunt the bismarck with civilian workers still on board?
 
:oops: I didn't want to overdo it - but seeing that you asked....here's a pic of Rodney undergoing a refit in 1942, with the 16in barrels being replaced (it's not quite the same, as the guns were more-or-less the same, but I'm confident they'd have put on new AA at the time, and would be surprised if she didn't get a new radar set or two as well):

Installing_16_inch_gun_on_HMS_Rodney_at_Birkenhead_Feb_1942_IWM_A_7692.jpg

That isn't necessarily a refit, merely replacing the barrels... Which were generally only capable of between 500-1000 full charge equivalents. The higher the MV, the lower the barrel life. The 16in Monitors in the Med for instance shot their barrels out without any realistic prospect of getting them back to blighty for replacements. as presumably Alexandria didn't have the facilities.

Which ties into my suggestion in an earlier dev diary.. Namely that Capitals can only be built, repaired or refitted in a province with 5 dockyards. Naval bases can refuel and rearm, but serious repairs ( probably crits) need dry docks of sufficient size.

Also I'm seeing lots of restrictions on the UK being introduced, but none for the benefit we accrued from the various treaties of our tubs having provision for increased bunkerage, which was also used to upgrade the armour.
 
We were being sarcastic.

I asked @Archangel85 yesterday whether it would be possible to convert carriers (back) into battleship/battlecruiser hulls, as obviously many of them started life as such, and we know you'll be able to convert the other way. He said he'd look into it, and I really hope it is possible when MtG is released.

It was never done historically for obvious reasons, but that isn't to say the player shouldn't be able to.

Unclear sarcasm was unclear given the response by Archangel85.
 
With the current naval mechanics (doomstacks), yes, but that looks like it will change.
I hope so. There won't be any super mega fleets, but still there should be 4 carrier fleets which will do a heck of a lot of damage. I tend to roll that out as Germany in early 1941, and then just crush the UK fleet over six months.

A 4 carrier fleet with supporting heavy, and light cruisers with a couple of battleships should still be allowed in a single task force since that was historically what some task forces were comprised of. Currently, the AI cannot stand against that fleet, if you take care of it and make sure it's repaired and the aircraft upgraded - it's unstoppable.

If they make the AI capable enough to stop that fleet with the proper forces, then I will be happy. Currently it's just well, my fleet is finally built, now all the oceans are mine.
 
Merchant/Transport Hulls for Refits

Developers, please consider introducing merchant/transport hulls and refit modules for them, so the players can produce:

  • Auxiliary cruisers/raiders - Germany, Italy, Japan, Nationalist Spain, England and Canada used them, offensively or defensively;
  • Escort carriers and Seaplane Carriers - England, USA, Japan mobilized this kind of units;
  • Landing ships - England and Japan converted several hulls;
  • Minelayers/minesweepers - Most raiders had minelaying capability and several merchants were used to break blockades and clear minefields.
Considering the treaties, and particularly the possibility of "cheating", this should include the option to adapt civilian hulls for the roles above mentioned, like all contenders did, before or during the war.

Best Regards, Guys.
 
People who complain that Paradox "just keeps releasing DLC as a money grab" are ignorant as hell.
 
Which ties into my suggestion in an earlier dev diary.. Namely that Capitals can only be built, repaired or refitted in a province with 5 dockyards. Naval bases can refuel and rearm, but serious repairs ( probably crits) need dry docks of sufficient size.

Aye, this is an important aspect. The industry required to build a destroyer or a submarine is categorically not the same standard as is required by a Yamato.
 
Wheeewww! Another cool diary, the wait becomes ever harder. :)

I really, really like the implementation of Naval Treaties, and the clever incentive for becoming a signatory even if you intend on expanding your fleet way beyond their limits. It adds nicely to the game's political layer.

Furthermore, it's nice to see the limitations to refits. After the last DD, I was already bringing up the significant differences between various early and later types of hulls, and wondering whether we could really just snap our fingers and let a ship grow ~20% in size via refit, but it appears the limitation to era-specific hull types is keeping things real.

(for historical examples, see the Japanese Mogami class becoming heavy cruisers after being built as light cruisers).
Yes ... yes, Mogami is totally a light cruiser. Look, she has small guns, that means she's a CL!

Mineo_Osumi.jpg


:D

They were barely usable as carriers because they didn't have a full flight deck. What flight deck they did have heavily restricted the heavy guns. It was a trade-off that achieved nothing.
Well .. that's not really a fair assessment, I think. They "achieved nothing" in part because they never even tried -- the pilots' training wasn't finished in time, so the planes were reassigned to a land base before the converted ships sortied.

Obviously, the very idea of aviation battleships could never hope to compete with dedicated carriers, but that's a bit like complaining an escort carrier would not have enough planes to wrest aerial superiority from a fleet carrier's air group. That doesn't render escort carriers a bad idea. In the end, Ise and Hyuuga still had 22 planes assigned each, and even seaplanes are better than no planes. In situations where players lose their carriers and it takes a lot of time to build new ones, or even completely convert a battleship into a full carrier, these "half jobs" don't sound like such a bad idea anymore. Not making them available at all may turn out to be a limitation.

Notably, Ise's and Hyuuga's complement even included some catapult-modified D4Y Suisei dive bombers, a single one of which allegedly almost sunk an Essex-class aircraft carrier. But since these had to land on an airbase or a conventional carrier after launch, I understand this would be hard to model, especially for such an edge case.

I guess we'll have to see what the modders can do, but I don't think the idea of BBVs is as bad as commonly touted -- if you temper your expectations and look at the alternative, rather than the ideal. BBVs are a crutch, nothing more, but also nothing less. The biggest hurdle for them may be that, as far as I can see, MtG does not support offensive/defensive use of seaplanes at all. In that case, even the apparently possible aviation cruisers become a bad idea, since we'd just end up halving their offensive power in exchange for some +Recon. We can probably achieve the same just by using several ordinary cruisers that carry one or two seaplanes each, without them giving up any of their naval rifles.

Any penalty to stationing the Pride in port during the entire war to gain the bonus without risks? (apart from losing the synergy with the admirals)
vlcsnap-2015-02-28-22h38m51s114.jpg
 
Hi Everyone, i am really enjoying reading the changes being made to the naval war (it was always the most annoying/uninteresting) Now one thing that has puzzled me for the past few dev diaries (and i apologize if it was covered but i do not remember). But will there be enhanced fleet management system? For example being able to set fleets as a certain makeup ( example : 2 Carriers, 4 Battleships, 10 Cruisers, 20 Destroyers)

And as ships are sunk:
A) ships that are sitting in a "Reserve Fleet" are dispatched to fill the gap
B) the dockyards that are producing the said sunk ship dispatches a replacement after completion is finished.

This i feel would reduce some of the issues with maintaining fleets as its always annoying keeping track of the fleets as they are in combat and sending more destroyers or other ships as they are sunk. and i always end up with a huge modern fleet sitting in harbor collecting dust.

You can take that idea to the next level and as new designs are created you can have them set to be sent to existing fleets replacing older models. which you can then work on modernization your fleet w/o compromising its fighting capabilities (and or alot of micromanaging)
 
If my recollection is correct you might be mistaken there. The Lexington and her sister were profoundly potent Carriers. Their armour actually helped keep them in the fight as well whereas the Yorktowns were particularly vulnerable to dive bomber attacks. They also maintained the largest US Air Groups until the Midways came on line. Just because they were lost in the first half of the war does not detract from that. They took on a substantially larger Japanese Carrier arm and held the line sufficiently for Hornet and Yorktown to relocate from the Atlantic.

Similarly, the Japanese fleet Carriers Akagi and the Kaga were again converted battle-cruisers and they also proved their worth by their air-group capacity.

I would argue as well that a refitted heavy hull would maintain a much stronger spine and as a result be more resilient. That is not to say they wouldn't be put out of action pretty quickly if they were not possessed of armoured decks like the UK was fond of, but they would still be pretty damned resilient from being destroyed.

All four of those examples were converted on the stocks, though, so they didn't need to 'break down' the BB/BC parts first iirc (and I could be wrong here), and things like machinery and boiler uptakes could be arranged early on in a way that was friendly for carrier operations. It'd be a larger job taking an already-built ship, breaking it down, re-arranging the necessary parts and then building it back up again.

That isn't necessarily a refit, merely replacing the barrels... Which were generally only capable of between 500-1000 full charge equivalents. The higher the MV, the lower the barrel life. The 16in Monitors in the Med for instance shot their barrels out without any realistic prospect of getting them back to blighty for replacements. as presumably Alexandria didn't have the facilities.

Which ties into my suggestion in an earlier dev diary.. Namely that Capitals can only be built, repaired or refitted in a province with 5 dockyards. Naval bases can refuel and rearm, but serious repairs ( probably crits) need dry docks of sufficient size.

Also I'm seeing lots of restrictions on the UK being introduced, but none for the benefit we accrued from the various treaties of our tubs having provision for increased bunkerage, which was also used to upgrade the armour.

It isn't necessarily (although I'd imagine in many cases for BBs it would have been), but it was in this case :). If you go to this site, and scroll down, you'll see for February 1942 (if you want to look at the source it's probably easiest to grab some of the text from the quote below and search on the page):

February

12th – At 1300 hours RODNEY, escorted by destroyers SOMALI, ORIBI and OFFA sailed from Hvalfjord for the Clyde.

14th – At 0900 hours in the Minches destroyers SOMALI detached for Loch Alsh.

15th – At 0015 hours RODNEY and destroyers ORIBI and OFFA arrived in the Clyde off Gourock.

16th – RODNEY escorted by destroyer PIORUN sailed from the Clyde for Liverpool.
En route, off Belfast the destroyer WATCHMAN joined the escort.
Later in the day RODNEY and destroyers PIORUN and WATCHMAN arrived at Liverpool and was docked at Cammell Lairds in Birkenhead.

After five weeks she was moved across the Mersey by tugs and dry docked in Gladstone Dock Liverpool.
During her refit she received attention to her hull, boilers and steering. The 16in gun barrels were replaced and addition 20mm Oerlikons were fitted. Her radar fit was upgraded and Type 282, 283 and 285 sets were fitted.

In this case, they also replaced some of the 16in barrels with Mk I rifling with 16in barrels with Mk II rifling (the three in A turret I think, but I'd need to look up the details - Rodney and Nelson both had periods where they had barrels with two types of rifling concurrently, making for ever-so-slightly different ballistic characteristics (although it apparently wasn't a huge problem, and the characteristics of the two types of rifling converged with wear making things better over time)).

More gameplay-focussed, the whole 'where can a ship refit/repair' is a tricky one, as a drydock was different to having a large naval industry. Singapore had one of the largest drydocks in the southern hemisphere at one point, but as best I understand it at no point had a shipbuilding industry that was anywhere near capable of building a capital ship from scratch. Sydney, similarly, by 1945 could do repairs to the BPF capitals and fleet carriers, but was a long way from being able to build it's own. Malta's another example of a place with excellent repair facilities but limited shipbuilding capability

It gets confused even further with floating docks, which both the US and UK used (the UK kept one at Gibraltar, iirc, although that's a particularly fuzzy memory). Both Valiant and Queen Elizabeth took advantage of Admiralty Floating Dock 5 at Alexandria after their close encounters with Italian frogman, for example (but were not fully repaired there).

From a gameplay perspective, repairing a capital ship in a smaller port could be seen as the use of a floating dock or similar. It's not perfect (for serious repairs, they'd usually be patched up in the floating dock then sent to somewhere with more substantial repair facilities), but at the end of the day there needs to be some balance between detail and gameplay, and given the amount of repair work that was done in ports in states with no significant shipbuilding capability, I personally don't feel its a bad simplification - but that's just my 2 cents, you've got a case as well and should pursue it with appropriate vigour :).