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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.

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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.
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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.
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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.
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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.
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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…
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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.
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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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Every developer diary makes me want Man the Guns more :(
 
They removed them. All Guns and Turrets. The Ship got brand new Turrets and Guns cause of the higher caliber and modernized gun technology.
The middle one was removed too, and - as far as I know - they needed its space for a newer generation of engine.
Actually they didnt receive new guns, they bored out the old 305mm guns into 320mm.
The entire reconstruction was criticized because the costs were nearly the same as building a brand new ship.
 
What about ships under repair or even under construction, will they also be captured when the provinces they are in are being overrun by enemy force? If this is true, that definitely will be a cool feature for the game!
And expanding on this, wouldn't it be interesting if you'd get a bit of a research boost after capturing something with new equipment?

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The naval changes are good so far. Just a reminder that Carriers made heavy cruisers and battleships almost obsolete by the end of the war except as ship to shore bombardment. I hope the changes in the DLC slow down the death stacks and stop the unrealistic naval losses. I am still waiting to see how you have fixed the naval air game.
During WW2 heavy ships were made obsolete by air aviation in the same way that infantry was made obsolete by tanks - they were still needed for balanced, effective fleets. The Allies happened to have enough cruisers and battleships to make direct attacks unfeasible and the situation was further exacerbated in the Pacific by the undisputed superiority of US radar/fire-control systems. This made night-time attacks (when air power is least effective) suicidal for the Japanese Navy.
 
During WW2 heavy ships were made obsolete by air aviation in the same way that infantry was made obsolete by tanks - they were still needed for balanced, effective fleets. The Allies happened to have enough cruisers and battleships to make direct attacks unfeasible and the situation was further exacerbated in the Pacific by the undisputed superiority of US radar/fire-control systems. This made night-time attacks (when air power is least effective) suicidal for the Japanese Navy.
It's ironic how that turned out, considering night warfare was among the IJN's specialties. But even the best human spotters, flashless powder, optical rangefinders and night combat seaplanes do not help much against radar-directed fire solutions.

Goes to show what an impact various technological advances had on the war(s), even aside from the obvious rise of naval aviation. For all the amazingly correct projections and decisions made by the IJN in the first 50 years of its existence, they did mess up their technology tree a bit when it came to WW2.
 
They removed them. All Guns and Turrets. The Ship got brand new Turrets and Guns cause of the higher caliber and modernized gun technology.
The middle one was removed too, and - as far as I know - they needed its space for a newer generation of engine.
Nah. The turrets were, as a whole, unchanged - they rebarreled the guns to accept larger shells, but the whole thing was mostly left being. The middle one, its barbette, and related magazines were instead removed to make space for more (and more modern) boilers, which is where the very hefty increase in speed came from.

Actually they didnt receive new guns, they bored out the old 305mm guns into 320mm.
The entire reconstruction was criticized because the costs were nearly the same as building a brand new ship.
The Conte di Cavour rebuilds made sense in the context of the naval treaties, as - while the cost was the same - building new battleships would have used up the 70k tons allotted to Italy, while the plan was to keep the old, modernized battleships around to counter battlecruisers and older battleships of the French navy, while keeping the extra tons around to be able to counter their new ships tit-for-tat.

The Caio Duilios were rebuilt when Italy had already left the treaties, and their cost is, as such, way more of a waste.
 
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I wish ship conversions fudged production a bit and used the naval base level the ship is docked at instead of using the existing dockyards for production (similar to how repair works). My guess is that conversions will rarely be an efficient use of dockyard time compared to building new ships so this feature won't get much use.
 
I wish ship conversions fudged production a bit and used the naval base level the ship is docked at instead of using the existing dockyards for production (similar to how repair works). My guess is that conversions will rarely be an efficient use of dockyard time compared to building new ships so this feature won't get much use.
you mean refit?
 
The Conte di Cavour rebuilds made sense in the context of the naval treaties, as - while the cost was the same - building new battleships would have used up the 70k tons allotted to Italy, while the plan was to keep the old, modernized battleships around to counter battlecruisers and older battleships of the French navy, while keeping the extra tons around to be able to counter their new ships tit-for-tat.

The Caio Duilios were rebuilt when Italy had already left the treaties, and their cost is, as such, way more of a waste.

As you point out indirectly here WR:
I think one point to consider that, while rather obvious, is kind of the naval "elephant" in the room.

Practicality
.

As a PM, you have this big ship, possibly quite a few of them. They are old, outdated and slow as hell. But... they are already built and maybe even paid for.

What the heck are you going to DO with them?

Ignore the issue and effectively commit the captain and crew to an early grave? Can you as PM even afford or stomach doing such a thing?

Short of siphoning manpower to cut them up and use the steel in another manner (a MP-intensive task in and of itself) you figure the best and most practical option is to find a way to refit (or retrofit) them to get as close to current naval standards as possible in a given time frame.

One of the things I absolutely love about great strategy games like HoI is being put in the unenviable position of having to make these decisions- and then living through the execution of your orders.

Will it be enough? Soon enough, to stem the tide of war? Must sacrifices be made early war in order to win the final victory?

I imagine that all those guys had stomach issues and stress disorder. I think I need to take a powder as they used to say in those days. :eek:
 
Wasn't the average life expectancy also shorter, by about a decade or two than now. Last I heard we were sitting at about seventy-five for men and seventy-eight for women. Back then, you married in your early twenties because you probably wouldn't be around to see the grandkids if you waited till your thirties or forties, like some do now.
 
That is a bit surprising to read. Just this past April - the ninth, as if I'd forget the date - I went in to have a routine operation to remove an oversized polyp from my colon [routine for the surgeon - not for me] only to learn I was violently allergic to one or more of the three medicines [Cefazolin, Metronidazole & Midazolam (ruddy Pharmaceutical names)]) that htye gave me. One was the general anesthetic, the other two were antibiotics. Good thing I was already strapped down. I thought I was gone. Literally, my vision reduced - a narrow, red-ringed focus - as my brain was starved for air, because my lung just suddenly up and went on strike. Took eight minutes to stabilize me, as they had trouble finding their on-site epi; someone had buried it under other stuff.

And I turned fifty six weeks later. So that thing about the infant mortality is surprising, but not difficult to believe. As for that polyp - there was a stage one tumor in the middle of it, but it had yet to grow through the wall of my colon, so they got it. How's that for effing luck.
 
A question just occurred to me - will narrow waters have a bonus to search rolls? Places where the waters are narrow - like the English Channel - but not a maze of navigable channels and islands that could help mask a small naval force - should have a higher detection chance, simply because there's less ocean to search.
 
Will the proper starting French leaders be placed at the start?

It should be Laval, Sarraut, Blum, and then Daladier.

Every time the Prime Minister is changed (via event), national unity drops a bit. This would help simulate France's weak government during WWII, which was one of the key factors on why the army was demoralized and the Germans won so quickly.

Though it's a small change, it would help with historical immersion. Perhaps it can be added in once the French national tree is updated in the future.
 
Thank you for creating this! This refit system, along with the ship designer are very similar (especially in intent!) to the Naval Expansion mod I did for Darkest Hour.

I'd also like to see carriers divided into those that carry the WW2 era CAGs with propeller planes versus those carriers able to carry jet CAGs. One should not be able to simply upgrade your CAG to a jet CAG on, for example, a Yorktown class carrier. It should take a conversion form regular (WW2 era) carrier to a jet CAG carrier. Midway class and Essex class carriers both went through those conversions, and both eventually also had some converted to an angled-deck carrier. Whereas starting with the Forrestal class the US built real purpose built jet CAG carriers (USS United States was also intended to be one, but was cancelled) that came to be known as supercarriers. Smaller carriers can't carry jets until the advent of VSTOL aircraft, too. I even made early carriers separate from WW2 era carriers with also early CAGs aboard, but since this game starts in 1936, that isn't as necessary here.

Are SHBBs modeled in this game? In my mod, I made every nation that builds them have to take a decision to spend time and money and IC to expand dockyard and port facilities to be able to handle them, thus giving pause before allowing just any Tom, Dick, or Adolf from building them. Also the US had to make the conscious decision to pass a Congressional act to expand the Panama Canal (costing double the amount compared to other nations to open the SHBB line). Historically the Montana class (which I view as SHBB level battleships due to the hull size) was authorized as soon as that act passed, even though it never actually was carried out.

I wonder if all this could be modeled in the MtG expansion. I even had other ideas I couldn't carry out due to game engine restrictions that might work here, as well.

I don't know if t his has been mentioned, but I also wonder what "Interservice Rivalry" will work out to be. :)
 
A question just occurred to me - will narrow waters have a bonus to search rolls? Places where the waters are narrow - like the English Channel - but not a maze of navigable channels and islands that could help mask a small naval force - should have a higher detection chance, simply because there's less ocean to search.
It seems it'll be a bit easier to find submarines, but there doesn't seem to be a bonus to spotting surface ships:

Screenshot_5.jpg


In fairness, "narrow" is probably quite relative here -- the Channel is still up to 240 km wide. It'd be difficult to assign a bonus to something that varies this much.

That being said, I think a small modifier might be appropriate?
 
I don't know if this was asked, but how the London Naval Treaty will affect the dominions and puppets?

It doesn't make sense that Great Britain cannot make a Heavy Battleship in London due to the treaty but that the same ship can be built in Melbourne by the Dominion of Australia.

I suppose that puppet countries have to abide to the same limitations as their overlord.
 
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The limitations would be the same, but their limits would be more in line with their capacity. And if they built something really big, it would take them forever.

I certainly hope it is as you say.


Now you can put a maximim of 5 naval factories for heavy ships in a single line. So as far as I know Australia can build one battleship or carrier just as fast as the United Kingdom, the only advantage of the British is that they can have more production lines and build more battleships at the same time.

In that regard I think it is important that the dominions have to abide to the London Naval Treaty just the same as the UK so they do not build heavier ships helping the British player to bypass the treaty from a certain point of view