• We have updated our Community Code of Conduct. Please read through the new rules for the forum that are an integral part of Paradox Interactive’s User Agreement.

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.

treaty_bs.jpg


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!).

Screenshot_8.jpg


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.
picture_refit_aa.jpg

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.
potf.jpg

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!
 
  • 1Like
Reactions:
If expansion is so focused on navy, can we get some more information about Italy? They are one of majors that start with generic Navy tech team, and earlier they were absolutely screwed and could never leave the port unless they wanted to be sinked by UK deathstack.

From the multiplayer perspective, this DLC will likely change nothing, UK will still rule the waves, US likely still rule the waves slightly contested by Japan, but if Italy will actually be able to at least protect sensibly their trade routes into Libya it would be a game changer.
 
War between two signatories ends it but the question is what if a player UK scraps most of the fleet for whatever reason

Good point, but if Britain scraps their fleet to declare war on a nation that now has a bigger fleet that's what I would call a bit of an own-goal.
 
  • 1Like
Reactions:
I'm wondering what if you simply build a very good BB template(?) and then build like 20 less upgraded version (say 4 less sets of guns of any variant) would this till take longer to upgrade then to build them from scratch?
 
Talking of really old ships, it'd be cool if there was some support for bringing back the old ships from mothballs (and sending them to be mothballed to free up naval manpower in the interwar, I guess). Gelderland/Niobe has a special place in my heart, she was comissioned in 1900 and went down fighting hard in 1944 against 132 Soviet aircraft sent on a specially prepared mission targeted at her alone.
 
Good point, but if Britain scraps their fleet to declare war on a nation that now has a bigger fleet that's what I would call a bit of an own-goal.
I get what you mean I more meant feeing up manpower/fuel or just not wanting a big navy and as a consequence other countries get cbs on each other spike World tension and a host of other unintended consequences. Would a minimum threshold work? As in 80% as long as the Royal Navy is x-size?
 
This looks good!

Also..
Since its a naval DLC, I have a question.
Why there isn't a firing animation used during shore bombardment?

There really should be an animation where the ships are firing their guns when they are involved in shore bombardment.
Would be cool if you could fix this.
 
Wonderful news, great DD!

How does the AI play the game of contracts? Are there bad boys willing to cheat or does the AI prefer to cancel the treaty?
the goal is roughly that the ai nations play the treaties as historical. but they might of course surprise you ;)
 
Looking good! I liked both this and the last diary, and will for sure use the designer, but... for immersion I would very much be able to choose from a predefined set of different designs as well. So, the ability to select e.g. the Dido class light cruiser, as well as its subclass Bellona with one slot of AA added. Would this be possible? Much like today's ship classes, really.

(...) but that might get a little too confusing so may be changed before release.
Yeah, good. By the way, what date did you say this was?
 
Is it actually going to be worth to build more ships, nations like UK already have so many ships so do it actually make sense to build more ships which consume more fuel and Manpower. Is it not simply better to spend the resources on upgrading the ships you have and Maybe build a few Carriers or cheap destroyers?

Is it actually Worth to spend the political Points to reduce the treaty limit as you the larger ships the more expensive they are and given that repair is no longer free, the major advantage of expensive battleships are gone. You can simply make up inferiority with numbers. The late 1944 hulls must have some big advantage to make sense to build them, especially the more expensive hulls which would take forever to build.
 
Great DD. Continues to amaze!
I'm really liking the idea of being able to bomb/capture refit ships in port as this shows more realism.
So now any thoughts on trying to do this with new production of ships?
 
Good point, but if Britain scraps their fleet to declare war on a nation that now has a bigger fleet that's what I would call a bit of an own-goal.

Well, yes, I agree that would be quite an own-goal. Though wouldn't it open the option for the (AI or player controlled) US (or another signatory) to do declare war on a particular nation? It might lead to some peculiar situations with the AI in singleplayer (though that would mostly be a situation of the player's creation) or be (ab)used in multiplayer in a coordinated fashion.
 
Retrofitting is the best part of the naval rework imo. So you mention it's possible to convert BBs etc. into moderate carriers as was done historically, but is it similarly possible to convert battleships into battleships with heightened aviation abilities? The Japanese navy did this on several BBs, namely the Yamashiro, Fusou, Ise, and Hyuuga. Finally, will it be possible to convert "convoys"/passenger ships into military ships as was attempted with the RN Sparviero?
 
Would it be possible to make a makeshift mini carrier to be able to have transport planes drop soldiers in a far away place?
You can't use transport planes from carriers, and it would be absurdly gamey if you could.