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HoI4 Dev Diary - The Imperial Japanese Navy (AAR)

Hello, and welcome back to another Dev Diary from the frozen wasteland that is Sweden in January. Today, we will have another short AAR of a naval warfare scenario, similar to the one we did earlier about raiding and submarine warfare.


This was played as an MP game between me and Niall (@Ceebie), with me defending the Empire of Japan’s honor against Niall’s filthy American imperialists.


Starting as Japan, I immediately face a number of issues that should sound very familiar: I have very limited resources, particularly in terms of oil. This is now a much bigger issue as I can still happily build ships and airplanes and tanks, but I won’t be able to run them for free. However, if I want to upgrade my ships (and knowing Niall, I absolutely do), I will need naval experience, and China is unlikely to provide me with a lot of it. So I need to run training missions for my fleet, which gobbles up fuel at a rapid pace (I could only take out my main fleet units for a few brief weeks before the fuel situation became critical).


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At the same time, while I could trade for more oil, it will cost civilian factories which I desperately need to build up my own industry or to trade for steel to continue my military buildup. I decided to keep the trading for oil to a minimum in order to more quickly build up my industry and increase the size of my fleet.


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My first target is, of course, China, and we start the war with them in the middle of 1937. It quickly becomes apparent that I underestimate the Chinese. Fighting rages hard along the border for several weeks, and a number of naval landings that attempt to force the AI to draw troops away from the main front are quickly contained by local garrisons, but at least not pushed back into the sea. Part of the problem is that the fleets tasked with invasion support contain some of my battleships, which eat up absurd amounts of fuel, and my attempts to turn the tide through prolific use of air support eat into my fuel supplies even more.


By early 1938, we are slowly grinding forward and have managed to inflict serious casualties on the Chinese, but my fuel stockpile has shrunken to just 30 days of current use. I curtail air support to only support my main thrust and send the naval forces providing shore bombardment back to port. Progress slows, but eventually we link up with the landing forces, at least saving me from an embarrassing early defeat. The massive amounts of Land XP also allow me to run through the doctrine tree quite a bit faster than Niall could ever hope to. Sadly the war in the Pacific will not be fought on land.


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It would take until early 1941 for the Chinese to fall, even though the writing is on the wall by the middle of 1940. I blame the poor infrastructure and awful terrain in China - my leadership is, after all, beyond any reasonable doubt.


In the meantime, Niall has been quietly modernizing his fleet and has started his rearmament. While a good amount of his effort is spent on helping out the British in Europe, I have no doubt that he has something in store for me. While I was deeply engaged in managing the war in China, I received some out-of-game intelligence (Niall bragging in the kitchen that his destroyer swarms would annihilate me) that makes me realize that my fleet lacks some key capabilities. The starting Japanese light cruisers are fairly mediocre, most have been built during the 20ies and are not up to the task of winning a firefight against the likes of a Brooklyn Class cruiser with no less than 3 light cruiser battery modules. What I do have is a lot of torpedoes, and I invest a little into researching upgraded torpedoes and better launchers. The Japanese Long Lance national spirit gives me another perk, as it negates the enemy screening to an extend, which means that my torpedoes can hit his capitals even through 100% screening.


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So while I was slowly grinding my way across China, I also decided on my buildup strategy:


  • No new battleships, since they eat up a lot of fuel and I have enough to cover my carriers. However, I did later decide to build at least one Yamato-class as an insurance against Niall developing modern battleships.

  • A force of 4 light carriers. Japan starts with two (Ryujo and returning fan favourite Hosho), with two Zuhio class building. While these only carry 40 planes each, they will be used to provide cover for operations in and around the Dutch East Indies.

  • A force of 4 fleet carriers, with another force of 4 joining later. Akagi and Kaga will be joined by 2 more Soryu class carriers and form the main strike force in the Central Pacific.

  • A heavy emphasis on air defense and torpedoes. After researching dual purpose main armaments, I design a new destroyer class with improved AA and better torpedo armament. These are joined by a quartet of light torpedo cruisers from the Japanese focus.

  • Lots and lots of Naval Bombers to damage the enemy during the approach and pick off stragglers. Once the battle is fought, his damaged ships would likely try and find a close naval base for repairs, so having naval bombers ready to attack them in port would let me finish them off.

  • Once I identified the fleet’s weakness in defense against destroyers, I also designed a version of the Mogami Class heavy cruisers dedicated to light gun support. I built another 4 of these.

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The fleet’s main objective, however, is to provide support for landings to seize resource rich areas in the Dutch East Indies. To protect the sea lanes to and from these islands, I will need to secure the Philippines, and that is where things get a little dicey.


While I have little doubt that my forces can take over Sumatra, Java and Borneo, Malaya might be a tough nut to crack, and I know that Niall has already started to fortify the Philippines. I have researched amphibious armor well in advance and with China now pacified, I start to turn up production in an attempt to give my marines a bit more punch and hopefully allow me to seize a foothold even against heavy opposition.

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Thinking ahead, I also research improved naval bombers and the next generation of carrier planes. Once my main objectives are secured, I will use swarms of naval bombers to hold them down while I move my fleets to stage two and take on Australia.


To give myself some more time to buildup, I delay my attack on the US until early 1942. This allows me to form a second strike force of two fleet carriers (Shokaku and Zuikaku, both repeat Soryus as I was unable to scrape together enough XP to design an upgraded carrier).


The first battles are very encouraging. Whenever my patrols find one of his scouting units, my strike fleets sortie and make short work of them, Niall’s vaunted Destroyer swarms being no match for my upgraded cruisers and destroyers. I am somewhat confident that I can attrit his screening forces faster than he can replace them, which would eventually force his fleet to remain in port or eat absurd numbers of torpedoes.

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Things quickly turn a little chaotic as my strike fleets and patrols intercept a number of troop convoys. While I first thought that these were going to the Philippines, they instead turn out to be trying to seize islands in the Central Pacific. Things don’t go well for him, as he has decided to keep his battleships and carriers on strike duty instead of covering his invasion convoys. Several divisions are effectively destroyed at sea, and the remains fail to gain any footholds.


At the same time, my invasions in the DEI, supported by the old battleships Ise and Hyuga, have run into stiff opposition while attempting to land in Borneo. I shift some tactical bombers into the theater to help break the stalemate, and we are starting to make progress. The two-pronged assault succeeds in establishing a foothold, but it is a reminder that Niall has not been idle and is ready to fight for every inch of ground in this vital area.

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While my marines still struggle to make landfall in the Philippines, a bigger drama unfolds in the Bismarck Sea. Niall has finally unleashed his main strike force, after one of his patrols found my carrier fleet.


The Battle of the Bismarck Sea does not go particularly well for the Imperial Navy. With several battleships detached for minor repairs, the US Navy breaks through my screening units and manages to do an end run on my carriers, sinking all four for no capital ship loses on their side. The survivors straggle home, many ships badly damaged during the ferocious engagement as my battle line attempted to screen against the full might of the US battlefleet.

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However, Niall’s victory has come at a steep cost. Most of his battlefleet is badly damaged, and he has nothing to follow his success up with. More than that, I still have 6 carriers in reserve (2 fleet, 4 light), and several hundred naval bombers scouring the Bismarck Sea means that he has to risk his battleships again to sail them to safer harbours for repairs. Several of them take further damage as they retreat, many of them out of the battle for almost a year.

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While Niall has blunted my offensive power quite severely, he has nothing to interfere with in my operations in the DEI, which were the main objective. Trying to use the Philippines as an unsinkable aircraft carrier has become next to impossible as trying to supply it with fuel would cost him too many convoys and tank his war support. The Japanese conquest of the southern resource area won’t quite be the lightning strike it was in history, but it is as inevitable as the rising of the sun.

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With hindsight, my performance in the naval war thus far comes down to:

  • Lack of radar allowing Niall to get the drop on me in a critical moment

  • Lack of training due to fuel concerns

  • Insufficient coverage of the seazones with naval bombers failing to disrupt the enemy on the approach

  • Not enough screening vessels to protect my carriers against his battle fleet. Although Yamato sunk several ships and survived to fight another day, spending the same amount of 3 heavy cruisers would likely have yielded better results

  • Good performance of my light forces when engaged on equal terms

That is all for today. Tune in at 1600 CET for another stream with an indepth look at fuel.
 
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Why should it last the entire game? Aren't we playing the game to be able to change historical events? If the Japanese had had a proper strategy and with some smart diplomacy, they could have forced China to the negotiating table. Sure, if the player makes the same mistakes and doesn't invest in the right kind of build up against China, by all means they should have to struggle, as seems the case.

Ideally an AI-versus-AI Sino-Japanese war should look something like the historical quagmire. These days every time I play the game Japan conquers China in late 1939.
 
Why should it last the entire game? Aren't we playing the game to be able to change historical events? If the Japanese had had a proper strategy and with some smart diplomacy, they could have forced China to the negotiating table. Sure, if the player makes the same mistakes and doesn't invest in the right kind of build up against China, by all means they should have to struggle, as seems the case.

The Japanese already have in-game penalties when taking the Marco Polo Bridge Incident focus.

Making the war with China more difficult than necessary would just lose more incentives to play as Japan.

EDIT: It makes sense, however, that if Historical Mode is on, AI Japan should be in a quagmire situation with AI China. Kinda breaks the immersion if AI Japan is able to defeat AI China fast.
 
Ideally an AI-versus-AI Sino-Japanese war should look something like the historical quagmire. These days every time I play the game Japan conquers China in late 1939.
Well, it is better than Chinese AI throwing AI-Japan out of continent because "it can". As Soviet Union I prefer to see Japan as one of major powers in the Pacific, able to struggle for some time, not naval landing of USMC in 1942 on Home Islands.
 
Well there is the spotting and intercepting phase as well, not just naval combat. If you use your carriers only after spotting the enemy and deploy your planes as a strike force it achieves what you want. We don't know how the intercept system works in detail - if your carrier force can be set to the equivalent of do not engage then it should try to keep out of the main battle while it's planes are constantly harassing the intercepters.

The battle mentioned in the AAR was one where his main battle force got ambushed because he FAILED his spotting. In that case then yes his carriers should be sunk.

Either way at least the new system represents battles in the Atlantic which is in improvement over the old system that didn't represent battles anywhere
We don't know exactly how it will work out, but they have basically already gone over all the mechanics so far and none of them pay special attention to carrier warfare. It was already this way before MtGs, and he wrote about a big naval battle in which it continues to happen, regardless if he was ambushed.

It almost seems like I am the only one who discusses the old Gary Grisby game Pacific War here on this forum.

If anyone else has, you would have seen how well done the carrier battles were done. It's an old turn based game, but it still has a lot of relevance on how to make some aspects of its mechanics which worked well, incorporated into HOI.

When you have two opposing carrier fleets out on basically whatever attack duty assigned to an area, they would automatically strike an opposing fleet, but specifically target a fleet with carriers, and then specifically target the enemy carriers first when the attack phase began. I'm guessing the first strike came down to who spotted who first.

Your planes launch based upon their readiness level and how many you have in your carrier fleet. It then shows the enemy fleet with its AA level, and CAP overhead, and your attack planes. First off, your fighters engage with the enemy fighters, then any that are still there get a chance to attack your CAS and Torpedo airplanes, and then any of your bombers that make it through then each have a small chance based upon experience level of the airgroup to hit a carrier, and while doing so also have to contend with the enemy AA. The damage you inflict depends on various factors such as bomb/torpedo strength, enemy ship durability etc . .

Then, the surviving enemy carriers will send a strike back on your carrier fleet automatically, and the whole thing is repeated but on your fleet. The entire game basically comes down to these battles since it's only on the greater Pacific theater, and carrier battles are the deciding outcome of who will win the war.

For an old 1993 game, I really think this is how carrier battles should be handled. I really wish Paradox would take some of their ideas from this old game.
 
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Well, it is better than Chinese AI throwing AI-Japan out of continent because "it can". As Soviet Union I prefer to see Japan as one of major powers in the Pacific, able to struggle for some time, not naval landing of USMC in 1942 on Home Islands.

I've seen some Hearts of Iron-type games handle it as a non-total war. So, if Japan wins they get some coastal cities from China, while if China wins Japan hands them Manchukuo.

As it is, Japan usually conquers the entirety of China in 1939, and we're left in the weird situation where Japan can keep control of the entirety of China without requiring a single garrison unit.
 
@Daelyn75 That seems significantly worse then how HoI4 handles sea battles as it totally ignores non-Carriers and that is more unhistorical then HoI4. The problem is that neither side have perfect information, so it's quite possible for BS to get in range before being detected. Putting your Carriers in a fleet with "no engage" and setting the planes lose will simulate long range carrier duels pretty well.

There is also the problem of running away as main tactic as that will cause trouble as soon as there is an objective that needs protecting by either side.
 
@Daelyn75 That seems significantly worse then how HoI4 handles sea battles as it totally ignores non-Carriers and that is more unhistorical then HoI4. The problem is that neither side have perfect information, so it's quite possible for BS to get in range before being detected. Putting your Carriers in a fleet with "no engage" and setting the planes lose will simulate long range carrier duels pretty well.

There is also the problem of running away as main tactic as that will cause trouble as soon as there is an objective that needs protecting by either side.
I never said it ignores non carrier fleets. It prioritizes the carrier fleets which is what should happen. If there are no carrier fleets around, whatever is spotted and within range gets attacked.

One of the ways I would level the playing field since the US had so much more production, and their airplanes were much more durable was not to get into a slugging match with them carrier for carrier, but I would move all my best land based Zeros, and several wings of my land based naval bombers into an attack zone around the Solomons and or the Marshalls, the Solomons was easier because airbases could be expanded better. My land based naval air forces weren't what was to kill the enemy carriers, but my land based Zeros would cut down the US CAP around their carriers, and then my carriers would go in and be the real sinking force. I believe they had land air forces attack twice per turn, and in between that was your naval movement and attack. So I would encounter a much reduced enemy carrier force in terms of their fighters which made it easier for my carrier air attack force to get through and hit their carriers.

It wouldn't be the same in HOI4 since its all real time, but a system like this where you use your best land based naval air along with your best and strongest carrier fleet to attack at the same time should hurt the enemy.
 
The battle mentioned in the AAR was one where his main battle force got ambushed because he FAILED his spotting. In that case then yes his carriers should be sunk.

While I can fairly agree with this statement - @Archangel85 clearly fails to give an idea of what kind of patrol found him first (and he may not have a way of knowing) - was it a PBY? a destroyer? radar? Getting the drop on the opposing fleet with all the big ships should certainly go this way - I agree. But the scenario below clearly indicates it was the surface ships that engaged. Historically though in battles such as Coral Sea, Midway, Philippine Sea, and others, one force devastated the other by getting the aerial jump - not the surprise arrival of the entire surface battlegroup. AFAIK, HMS Glorious was the only carrier of the entire war to be lost to enemy surface action and she and her two destroyer escorts were all lost (Thanks Scharnhorst + Gneisenau)

While my marines still struggle to make landfall in the Philippines, a bigger drama unfolds in the Bismarck Sea. Niall has finally unleashed his main strike force, after one of his patrols found my carrier fleet.


The Battle of the Bismarck Sea does not go particularly well for the Imperial Navy. With several battleships detached for minor repairs, the US Navy breaks through my screening units and manages to do an end run on my carriers, sinking all four for no capital ship loses on their side. The survivors straggle home, many ships badly damaged during the ferocious engagement as my battle line attempted to screen against the full might of the US battlefleet.

Not enough screening vessels to protect my carriers against his battle fleet. Although Yamato sunk several ships and survived to fight another day, spending the same amount of 3 heavy cruisers would likely have yielded better results

All these quotes just continue to hammer home the idea of "Guns, guns, guns - battleships, battleships, BATTLESHIPS!!!!!!"

The second world war was the first time in history that two opposing forces sunk each other's ships without ever sighting each other directly. And this became the norm for the single greatest area of naval conflict in the entire war - the Pacific Ocean. To not find a way to represent this in at least a passable form would be a shame and a massive missed opportunity for Paradox in what is genuinely one of the greatest grand historical strategy games.

I would hope the devs pay attention to this feedback and address it head-on as to how they imagine or see the game recognizing this dynamic and massive historical change that still dominates the current world view of naval warfare. I think if the devs came out and simply said, "Hey this is how we foresee carrier engagements working," and then explaining how they see this concern of a lot of us being addressed, and why they chose certain mechanics, it would go a looong way to assuaging fears - whether it is a clunky approach or not. By not having addressed it directly, it gives a lot of reason for concern and uncertainty among fans and continued (admittedly inferred) avoidance of the issue appears to many as confirmation that the game engine is either not capable of handling over the horizon carrier battles without an even more massive re-write of the code or they have not addressed it all. In either case, Man the Guns is looking to be a literal description of the main naval expansion for the series - better naval combat -with guns!!

EDIT: I forgot the St. Lo at Samar - a CVE being sunk to gunfire, so like two total carriers ever lost to gunfire in the war - every other loss was to aircraft or submarines
 
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AFAIK, HMS Glorious was the only carrier of the entire war to be lost to enemy surface action and she and her two destroyer escorts were all lost (Thanks Scharnhorst + Gneisenau)

EDIT: I forgot the St. Lo at Samar - a CVE being sunk to gunfire, so like two total carriers ever lost to gunfire in the war - every other loss was to carrier aircraft or submarines
There was also USS Gambier Bay that was sunk by gunfire. But it's a mistake to look too blindly at history as Japan and US only had so many battles to fight before Japan ran out of ships that there is limited amount of data. Both sides were also very carefull with their main assests, the BB's and more willing to risk the more expendable CV's.
 
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Hopefully getting a carriers to not be sunk left right and centre by surface assets is a simple mater of increasing their disengagement chance. However that still doesn't address the issue that in the Pacific those surface assets might be hundreds of miles away from each other while the carrier air groups fight it out and attack the fleets.

So if say two carrier fleets are set to "Do Not Engage" and they are in the same sea zone, with the air wings set to naval attack and air superiority in the sea zone, do you end up with a kind of war of attrition with both sides trading air attacks? Maybe you force the air attacks to be more concentrated in time and you start to get something like carrier fleets each trying to get in the first big strike?
 
You can always look at who gave you a disagree under ratings recieved on your profile.
I do agree that a sortable division template list would be nice QoL.
It may yet come in 1.6.x. One can hope.
It wasn't shown in latest dev stream. It wasn't mentioned in dev diaries, and as we can see from this one, devs can't say, they have PLENTY stuff to write about. So, it is safe to assume, that there is no sorting interface - neither buttons, nor drag&drop.
 
It wasn't shown in latest dev stream. It wasn't mentioned in dev diaries, and as we can see from this one, devs can't say, they have PLENTY stuff to write about. So, it is safe to assume, that there is no sorting interface - neither buttons, nor drag&drop.
I'm aware, by 1.6.x I meant one of the smaller patches after 1.6 (1.6.1 e.g.) There is a precedent for smaller additions to make it into maintenance patches.
 
All these quotes just continue to hammer home the idea of "Guns, guns, guns - battleships, battleships, BATTLESHIPS!!!!!!"

Well it was like that before so I can only assume it will be like this again. Which is odd because before you could sort of just assume well it's an entire seazone and this is where many battles could be taking place, but now it's one battle in a localized spot just specific to this battle and this battle alone. They cannot get away with sending your guns forward while the carriers stand back and decide to attack as soon as your warships start shooting at each other anymore.

Yup, just great.

I get that you could just unleash your planes into the entire seazone from your carriers but that's not really much difference than naval bomber attacks, just shorter in range.

A carrier strike could be absolutely devastating to ships. If organized right, as a concentrated attack that with good pilot skill, smaller airplanes (than land based naval bombers), and the simultaneous high dive bomb attack and low torpedo attack made it extremely difficult to out maneuver/intercept/shoot with AA guns.

The old quote from Mussolini about Italy being an aircraft carrier means he had no idea about the power of modern (then) carrier strikes.
 
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Neat little video by TIK that also looks at some of the fuel, logistic and reasoning for securing ports to shorten transit distance to the front, also the black market of fuel disappearing thus hampering efforts. Alot of TIK videos, especially his feature length documentaries really go into detail about the effort the allied made to secure supplies near the front in the Africa campaigns before an attack, building infrastructure and pipelines, even diversions to act has a ruse to give the impression an attack was coming from that area not to mention the well known supply issues Rommel Afrika Korp had.

Would highly recommend TIK channel to anyone whom is interested in all the finer details of campaign during world war two, even some of the not so well known and detailed ones that the history channel or mainstream documentaries rarely cover. Even little anecdote stories of commanders attaching armchairs on top of tanks so they can conduct the battle from atop their tank, to commanders rallying retreating tank divisions and spear heading it in a jeep. These notable commanders are in HOI too, like Jock


With the Japaneses AAR and the talk of managing fuel, totally hyped for the new layer of strategic depth this has the potential to bring.


Video on O Connor during Operation Compass

 
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@Daelyn75 War in the pacific Admirals edition 2005 published by Matrix. And yes, its my source and inspiration of how a pacific war simulation should work. its pretty close to a RTS. it mixes attacker defender phases in a turn similarly to how HOI IV uses RTS phases to resolve battles. I see a lot of Gribsy's ideas at work in the PDX games especially ideas borrowed from Art of War. I can only hope they can borrow from War in the Pacific. I am not talking about code stealing; I am talking about mimicking results
 
@Daelyn75 War in the pacific Admirals edition 2005 published by Matrix. And yes, its my source and inspiration of how a pacific war simulation should work. its pretty close to a RTS. it mixes attacker defender phases in a turn similarly to how HOI IV uses RTS phases to resolve battles. I see a lot of Gribsy's ideas at work in the PDX games especially ideas borrowed from Art of War. I can only hope they can borrow from War in the Pacific. I am not talking about code stealing; I am talking about mimicking results
I couldn't agree more. I was talking about this game years before HOI4 launched and said that there is much that they can use from that old game. I never played a version but the original 1993 one. I also played a lot of War in the East, and it's original Second Front - I played to death when I was 16 since it was about the first real strategy game that I ever got into. I guess Civilization, and Romance of the Three Kingdoms don't really count as military strategy games.

They still have a lot to do when it comes to hitting airfields. I want to be able to bomb and destroy aircraft on the airfields like you could do in those Gary Grisby games. All you can do in HOI4 is damage the airfield.