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Developer Corner | Aerohydrodynamics

Hello everyone!

It has been a while since the last dev corner, as many of us (including myself) went on vacations - but now I have returned, even if it has been quite hard to readjust my brain back to the work frequencies. As usual, keep in mind that everything discussed here is in a relatively early stage, and as such is subject to change, especially all the numbers and values. There is also quite a number of placeholder art.
Today we will talk a bit more about Islands, Carriers (and changes to them) and also about a new branch of Special Forces, so buckle up!

Strategic Locations

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Truk is what we call a ‘strategic location’, a place that can have increased building capacity or potential. In this case, currently it is a ‘placeholder’ name of Natural Harbor increasing the level cap of Naval Base Truk in Caroline Islands from 6 to 8. (note, that doesn't mean all the Caroline Islands have that increased level cap). This increased level cap of 8 can be quite important as it will allow…

As I mentioned in the Hydrodynamics Dev Corner, not all islands will be equal under the new system. We have created a concept called ‘Strategic Locations’ - that due to specific circumstances, historical importance, geographical location etc. deserves to be a bit more unique, while also having increased gameplay importance. Those locations will have increased limits for certain buildings, depending on the type of the strategic location. Some of the ‘Islands’ like Truk or Guam, may have increased Naval Base caps, others could have increased Airfield or Fort Caps. Or have a mix of them.

Defending Against Naval Strikes

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In this screenshot, you can see that planes from the British Carriers shot down some of the incoming German Naval Bombers performing Naval Strike.

One of the things that didn’t sit quite right with me for a long time, was the fact that whenever Naval Strike was performed on the Taskforce that included Carriers, Carrier Planes would sit idle and twiddle their thumbs. Now, carrier planes will participate in defense of the taskforce against Naval Strikes - with numbers depending on a few factors.

Carrier Missions

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In these screenshots you can see that while the task force is executing the mission (in this case it was naval exercises), planes on that carrier can also perform the air missions at the same time. In the second screenshot I’ve selected all planes to do exercises, while in the last screenshot I’ve opted for fighters to provide air cover and superiority, while I ordered my taskforce to operate in the North Pacific Sea Zone.

Another update when it comes to the Carriers that we will be doing, is the ability to set and execute air missions for the Carrier Air Groups, while the taskforce that contains Carriers are performing the missions. Planes will be executing the missions selected in the same region that the taskforce is currently operating in.

Carrier Hangar Detection Changes

And another change for Carriers, is the introduction of ‘Carrier Sub/Surface Detection’ values on the Hangar modules. Essentially what it does - it provides increased Sub / Surface detection to the ship scaled by the % of the planes it currently has.

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Deck Space / Hangar for the ‘regular’ carriers provide +2 Carrier Sub Detection and +5 Carrier Surface Detection. For example, a carrier with 3 hangars, will have a Deck Size of 60, and +6 Carrier Sub Detection, +15 Carrier Surface Detection. If it would have a full compartment of 60 planes, then it would get +15 Surface and +6 Sub Detection, while if it would have only 30 planes, it would only provide +3 Sub Detection and +7.5 Surface Detection. As usual, keep in mind those values may be adjusted down the line.


New Special Forces

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Who will guess which one is the new branch of Special Forces?

To fight in all the jungles and on the islands, we are introducing a new branch of Special Forces - which we internally called for quite some time ‘Jungle Specialists’. This temporary name was great as long as they remained on the design board, but for the actual implementation finding the right name for them proved to be quite challenging to me. They went under a few ‘name iterations’ (amongst them some like: Jaegers or Chindits), but finally decided to name them Rangers. But hold up, aren’t there Rangers in-game already as a Support Company unlocked by the Mountaineers Special Doctrine, you will ask? Yes, and they will be renamed to Recon Rangers. Recon Rangers will be now unlocked by either picking Mountaineers Special Doctrine OR Rangers Special Doctrine. Rangers specialty will be fighting in the Woods and Jungles, and of course they can be further customized and boosted by the Rangers Special Forces Doctrine branch.

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And this is the new special forces doctrine branch in all its FINAL_BACKUP_DRAFT_FINAL_V5 glory and form.

And that’s pretty much it for this dev corner from my side. In time we will return with more dev corners, including me talking more about things that are opposite to dry amongst others. I am really curious to see and read all your feedback and opinions on what I mentioned today.

Thanks for reading and until next time, farewell!

/Zwirbaum

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I am going to leave you with another teaser for one of the new ‘toys’ we will talk about in the future. This shouldn’t be a hard guess, I think?
 
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The escort carrier (CVE) spelled the doom for both the German wolfpacks and IJN sub fleets. A submarine at periscope depth was surprisingly easy to spot and the snorkel tech did not save them. Dedicated ASW CVs and a/c would also allow for a new air tech - aerial depth charge/bomb - used by Liberators, Hellcats, PBYs, etc. by the British, Canadian and Amercian fleets in the Atlantic and Pacific.
If they have detection, can't torpedo bombers already attack subs?
 
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Is that mostly a balance concern, or is there a historical reason why the USSR should have an easier time getting special forces?
I used USSR because it's the worst example of it in my opinion, when you compare it to germany having to only do 2 35 day focuses to get a 2nd special forces doctrine, compared to the USSR requiring you to go down the naval branch for the 2nd one, to me it's a bit of weird balance
Let's be real, the main reason it's op on Germany isn't because Germany actually builds all three special forces, it's because German tanks benefit from 30% special forces attack when they use amtracs.
Of course yeah, but this ties into my main complaint in the first place, germany for example can get those extra stats from a 2nd doctrine while the USSR cant because like i said, you need to go down almost the entire naval branch for it
There are a lot of things that could change here without touching the entire system.
I'm not asking for the entire system to be overhauled, simply on how in certain cases you get extra doctrines
Diversify Elite Forces for example you could give to just everyone instead of unlocking it via focuses for certain nations
 
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Will the new Special Forces battalion use less supply? There is a serious need for a troop type that just uses less supply. Think Green Beret or SAS. Units meant to operate more or less independently in remote locations.
 
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If they have detection, can't torpedo bombers already attack subs?
In game terms they can but torpedo bombers were useless against submarines in the war,..... for obvious reasons. CVEs carried about 24 aircraft (small hulls) they might carry just a squadron of fighters and another of dive bombers. By mid-war, most CV fighters were like their land-based counterparts, they were multi-role aircraft (6 - 8 MG and bombs/rockets.

If the goal is more historical accuracy then there needs to a role for naval dive bombers and fighters. The aerial DC interaction with submarines would be such a tool.

On the larger fleet CVs the number of torpedo bombers actually declined as the war progressed as dive bombers had executed most of the naval damage by CV strikes from Coral Sea onwards. CV CAS (dive bombers) could more easily be used for supporting ground troops than a torpedo bomber.
 
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I used USSR because it's the worst example of it in my opinion, when you compare it to germany having to only do 2 35 day focuses to get a 2nd special forces doctrine, compared to the USSR requiring you to go down the naval branch for the 2nd one, to me it's a bit of weird balance

Of course yeah, but this ties into my main complaint in the first place, germany for example can get those extra stats from a 2nd doctrine while the USSR cant because like i said, you need to go down almost the entire naval branch for it

I'm not asking for the entire system to be overhauled, simply on how in certain cases you get extra doctrines
Diversify Elite Forces for example you could give to just everyone instead of unlocking it via focuses for certain nations
Personally I'm fine with different countries being better at it than others. The game has its roots in history, it's not really balanced around being an esport.

This is kind of facetious from me, but it's kind of like asking "why can Germany get bonuses to building mils from day 1, but the USA has to go down an entire focus branch to get off the great depression and undisturbed isolation first?"
 
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Will the old problem that it depends on the time zone if there is 1 or 2 air strikes in a naval battle in daylight be fixed? Now most air zones have only 1 in daylight, as far as I tested. While carriers are strong with 2 air strikes, they suck with only 1. A strike every 6 hours in a naval battle would solve the problem and also give the carriers a reasonable strength.
 
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Personally I'm fine with different countries being better at it than others. The game has its roots in history, it's not really balanced around being an esport.

This is kind of facetious from me, but it's kind of like asking "why can Germany get bonuses to building mils from day 1, but the USA has to go down an entire focus branch to get off the great depression and undisturbed isolation first?"
Nothing wrong with asking HOI4 to be more historically accurate and less arcade game. The nations involved in the war had different strengths and weaknesses. As a 'wargame' it does not need to give every nation every niche unit..

My issue with a new "Ranger" special force is this will generate entire armies of rangers (tip of the spear and other bonuses allowing 48+ battalions),.... and these simply did not exist. The Chindits were a regiment or two. US army rangers were a few battalions supporting amphib operations. British Commando units were also battalion size.

Airbourne, Marine and Mountain divisions were real things and even deployed in corps. Rangers were not.

A better addition would be glider infantry, artillery and AT battalions that would properly flesh out airbourne divisions and allow for the creation of 'air landing' divisions (light infantry that could be flown into airheads). These were also a real thing.
 
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Personally I'm fine with different countries being better at it than others. The game has its roots in history, it's not really balanced around being an esport.
My angle is mostly about balance, but it also prevents experimentation and isn't really historical/rooted in history at all, if you want to make the best use of marine infantry (which the USSR did use a decent chunk of IRL) you then cant use the paratrooper doctrine to make better use of your paratroopers, which the USSR also did use, same with mountaineers
 
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Love all the changes, but I will admit the Rangers bit is gonna take some time for me to get used too. Could we not call them commando's or Raiders. Something like that? Anyways love it and excited for all that is coming!
 
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But hold up, aren’t there Rangers in-game already as a Support Company unlocked by the Mountaineers Special Doctrine, you will ask? Yes, and they will be renamed to Recon Rangers.
Do you mean, like.. "Scouts"?
 
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No offensive seaplane carriers are planned - sorry to tenderly crush your hopes in that case. :(
Would it be possible to use seaplanes from harbors, not just from airports or carriers. For example the Japanese flew seaplanes from small ports and coasts of many Pacific islands that did not have an airport.
 
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Proposed cruiser hull types
  • Large Cruiser Hull - heavy cruisers and large light cruisers (Mogami, Cleveland, Town) armed with medium battery or light medium battery
  • Cruiser Hull - many type light cruisers and anti-aircraft cruisers armed with light medium battery, light battery, light battery dp.

and ...

  • CVL - light aircraft carrier - can be converted from a Large Cruiser Hull
  • CVE - escort aircraft carrier - can be converted from Cruiser Hull
 
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Will there be any modification to facilitate Midway style battles where battle happens between carriers and aircraft only (as historically happened in battles involving carriers)? I am begging for this
 
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finally a fix to carriers...

god i wish youd fix the grossly distorted sea and air zone tiles, the ones near the equator are far too small and the polar ones far too big which ofc has a massive effect on the naval game in these regions. it's far too easy to cover the entire pacific with heavy frame based naval bombers and far too hard to do something about the north sea and north atlantic...
 
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Rangers specialty will be fighting in the Woods

I assume this isn't a subtle hint at a new terrain type and is instead supposed to say "Forest"?
 
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In game terms they can but torpedo bombers were useless against submarines in the war,..... for obvious reasons. CVEs carried about 24 aircraft (small hulls) they might carry just a squadron of fighters and another of dive bombers. By mid-war, most CV fighters were like their land-based counterparts, they were multi-role aircraft (6 - 8 MG and bombs/rockets.

If the goal is more historical accuracy then there needs to a role for naval dive bombers and fighters. The aerial DC interaction with submarines would be such a tool.

On the larger fleet CVs the number of torpedo bombers actually declined as the war progressed as dive bombers had executed most of the naval damage by CV strikes from Coral Sea onwards. CV CAS (dive bombers) could more easily be used for supporting ground troops than a torpedo bomber.
In game terms you may be correct, but in reality, the Air component on CVEs was dependent on their mission.
CVEs used many different planes for different missions.

As copied from Wikipedia:

Specific Missions:
  • Convoy Escort:
    CVEs were crucial for protecting merchant ship convoys, especially in the Atlantic, by providing air cover against U-boats and enemy aircraft.

  • Amphibious Assault Support:
    They provided air support during Allied landings, such as those in North Africa and the Pacific, including close air support, artillery spotting, and anti-aircraft and anti-submarine patrols.

  • Aircraft Transport:
    CVEs ferried aircraft to and from various locations, including overseas bases, supplementing the role of fleet carriers.

  • Antisubmarine Warfare:
    In later stages of the war, CVEs were organized into hunter-killer groups specifically targeting German U-boats.

  • Support for Fleet Carriers:
  • CVEs could also act as backup for fleet carriers, particularly in areas where their slower speed was not a major limitation.
Specific Aircraft Types deployed on CVEs:
  • Fighters: F4F/FM-2 Wildcat (US), Martlet/Sea Hurricane (UK).

  • Dive Bombers: SBD Dauntless (US).

  • Torpedo Bombers: TBF/TBM Avenger (US), Tarpon/Avenger (UK).

  • Other: Some CVEs also carried scout/observation aircraft like the SOC Seagull (US).

  • Ferry Role: CVEs were also used to transport aircraft, including P-40 Warhawks and P-38 Lightnings, to various locations.
 
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Will planes on air missions from a carrier get bonuses to air combat/naval combat? In naval combat, carrier navs get a 10x damage modifier to ships and I think fighters get a 5x modifier to planes. Will these be active in the regular air missions?
 
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