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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).


Screenshot_2.jpg



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.


Screenshot_4.jpg


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.


Screenshot_5.jpg



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.


Screenshot_1.jpg



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.

Screenshot_6.jpg

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.

Screenshot_16.jpg

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.

Screenshot_11.jpg


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.

Screenshot_13.jpg


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.

Screenshot_8.jpg

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.

Screenshot_15.jpg

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.

Screenshot_14.jpg

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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This is just absurd. No excuse for this kind of delay. Even CA gave a nice explanation of why it took so long to implement Norsca into TWW2 and how it would throw off the content schedule.

What exactly has been happening for the past YEAR?

To add insult to injury podcat is acting as if its business as usual when under his direction Hoi4 has been outpaced by every other dev team at the company several times over.

No explanation, no apology, just releasing a multiplayer focused aar as if it was a fun extra right before release.

It's not hunky dory. There's no release date, not even a ballpark one. They've had all the time in the world.

This is an expansion, not half life 3 or ff XV.

At this point it looks more like star citizen.

I cant play promises, or aars, I cant play coming soons I'm sure people will say that it's going to be jam packed with content.

If it was that jam packed with stuff then they wouldn't be putting out a boring aar between players. Nobody cares about multiplayer. It's a small fraction of the overall games. Yes I'm sure a bunch if people will say they like it but they are still in the minority.

At this point it should be clear that this expansion is not coming until the summer at EARLIEST. It probably will not be great either.


I will gladly eat crow for days on end. I want to be wrong. I want it to be finished. I dont believe I am, whatever they've been doing for the past year, it seems like a tiny fraction of it has been finishing a project that should've been done at latest THREE MONTHS AGO.
 
This is just absurd. No excuse for this kind of delay. Even CA gave a nice explanation of why it took so long to implement Norsca into TWW2 and how it would throw off the content schedule.

What exactly has been happening for the past YEAR?

To add insult to injury podcat is acting as if its business as usual when under his direction Hoi4 has been outpaced by every other dev team at the company several times over.

No explanation, no apology, just releasing a multiplayer focused aar as if it was a fun extra right before release.

It's not hunky dory. There's no release date, not even a ballpark one. They've had all the time in the world.

This is an expansion, not half life 3 or ff XV.

At this point it looks more like star citizen.

I cant play promises, or aars, I cant play coming soons I'm sure people will say that it's going to be jam packed with content.

If it was that jam packed with stuff then they wouldn't be putting out a boring aar between players. Nobody cares about multiplayer. It's a small fraction of the overall games. Yes I'm sure a bunch if people will say they like it but they are still in the minority.

At this point it should be clear that this expansion is not coming until the summer at EARLIEST. It probably will not be great either.


I will gladly eat crow for days on end. I want to be wrong. I want it to be finished. I dont believe I am, whatever they've been doing for the past year, it seems like a tiny fraction of it has been finishing a project that should've been done at latest THREE MONTHS AGO.
We're all in the same boat, even Paradox who wishes this expansion came out months ago. If there is a delay like this, one can only logically conclude that there is a good reason for it. It's not like they are doing this just to make us squirm.

The game was delayed quite a bit before release due to not being able to get the game working the way they wanted it too. I'm guessing the same thing is going on with this DLC.
 
Hello again,

today we should think about "Romanian(as part of axis) flotilla and the first EU-wide transportation river network:

IF:

Austria (part of Axis or occupied)
Yugoslavia (part of Axis or occupied)
Hungary (part of Axis or occupied)
Romania (part of Axis or occupied)

AND IF:

Rhine river
Main river
Donau river

100% under Axis control

THEN

Romania /Germany could decide to create the 30th U-boat flotilla for the black sea. It need around 1 year to transfer 6 small submarine from baltic sea to Black Sea.

https://en.wikipedia.org/wiki/30th_U-boat_Flotilla

it happened in real ww2 is still miss this decision. I know the difficulties for programming ship transfers but if i play as New Zealand i can also demand 2 light cruisers from UK.
Any plans for this decision to create the 30th U-Boat Flotilla(as germany or axis romania)?

You're posting (imo at least) some interesting ideas, but might they be better served in the suggestions part of the forums (if you haven't already)? I could imagine they'd be easy to miss in a long-ish dev diary thread.

I cannot think of any carrier vs carrier battle that had their surface ships engaging with each other.

I think it was at the Battle of Santa Cruz where the Japanese surface 'vanguard' force got very close to the US ships scuttling Hornet - but you're quite right in that there was never a proper surface and carrier engagement in the same battle. Depending on what the actual HoI4 battles represent (at the moment they go on for a quite a while, so they could be interpreted as representing a clash between carrier aircraft during the day then surface fleets at night - iirc at one point Marc Mitscher wanted to send his BBs off to engage the Japanese surface forces at night, during the Battle of the Philippines Sea - but was sensibly overruled or decided otherwise (can't remember which). So as far as I understand it, it's not implausible that it would happen, even if it didn't really happen in the historical WW2.
 
I think it was at the Battle of Santa Cruz where the Japanese surface 'vanguard' force got very close to the US ships scuttling Hornet - but you're quite right in that there was never a proper surface and carrier engagement in the same battle. Depending on what the actual HoI4 battles represent (at the moment they go on for a quite a while, so they could be interpreted as representing a clash between carrier aircraft during the day then surface fleets at night - iirc at one point Marc Mitscher wanted to send his BBs off to engage the Japanese surface forces at night, during the Battle of the Philippines Sea - but was sensibly overruled or decided otherwise (can't remember which). So as far as I understand it, it's not implausible that it would happen, even if it didn't really happen in the historical WW2.

Yes, and at Midway, Nagumo tried his best to close his 2 BB fleet with the US carriers after he'd lost all of his but couldn't get near them. The only time a surface fleet has touched a carrier fleet was at the battle of Leyte Gulf.

I'm not ruling it out that it shouldn't happen, but what I am saying is that carrier fleets that engage with enemy carrier fleets, never, not once, just sent all their BBs, CA/CLs, and DDs towards each other while they attacked from the air.

Carrier fleets fought each other from hundreds of KMs away, where the only contact was between the airplanes and the ships, not the ships vs the ships while the airplanes attacked the opposing carriers.

I'm not sure why the devs decided to do this, it's completely unrealistic, never happened, and it just doesn't need to happen. So now we are going to have carrier battles where your surface fleet take losses because they are shooting at the enemy surface fleet, and all of this because both sides decided to get within shooting distance with their surface ships guns.

They should have made a special mechanic to have carrier battles, in which the surface ships never even see each other.

Why? Because that is the way they were fought. There was no need to get that close, and this is why carrier fleets are the king of the oceans today, because they can project massive firepower against opposing fleets just from their aircraft.

Axe99, this is in no way an attack on you. I'm just trying to raise the issue so people start talking about it, and for the devs to take notice.

Carrier battles in the WW2 are the most important battles to get right, because those with carriers could dominate the seas.
 
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This is not correct. I played France yesterday with heavy fortifications and the AI did not bang its head on my forts.
From what I recall, the German AI is hardcoded not to attack the Maginot Line.

I last played about eight months ago as Japan, and the AI wasted upwards of 200k soldiers attacking two of my mountain forts in Italy.

Either way, question stands whether the AI will be able to manage the new resources and combat mechanics, or if we'll see a repeat of Stellaris' latest patch where the AI didn't know how to use the new mechanics and is flooded with free resources in an attempt to compensate for its incompetence.
 
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That is not exactly true
Thanks for that information. I literally didn't know about it. I guess in going over what happened in and around Norway, the history I read glossed over this part.

Now I am wondering why they had this:

"There is a degree of mystery about the sinking of the Glorious because papers relating to the sinking have a "100 year rule" embargo on their release."
 
Yes, and at Midway, Nagumo tried his best to close his 2 BB fleet with the US carriers after he'd lost all of his but couldn't get near them. The only time a surface fleet has touched a carrier fleet was at the battle of Leyte Gulf.

I'm not ruling it out that it shouldn't happen, but what I am saying is that carrier fleets that engage with enemy carrier fleets, never, not once, just sent all their BBs, CA/CLs, and DDs towards each other while they attacked from the air.

Carrier fleets fought each other from hundreds of KMs away, where the only contact was between the airplanes and the ships, not the ships vs the ships while the airplanes attacked the opposing carriers.

I'm not sure why the devs decided to do this, it's completely unrealistic, never happened, and it just doesn't need to happen. So now we are going to have carrier battles where your surface fleet take losses because they are shooting at the enemy surface fleet, and all of this because both sides decided to get within shooting distance with their surface ships guns.

They should have made a special mechanic to have carrier battles, in which the surface ships never even see each other.

Why? Because that is the way they were fought. There was no need to get that close, and this is why carrier fleets are the king of the oceans today, because they can project massive firepower against opposing fleets just from their aircraft.

Axe99, this is in no way an attack on you. I'm just trying to raise the issue so people start talking about it, and for the devs to take notice.

Carrier battles in the WW2 are the most important battles to get right, because those with carriers could dominate the seas.

The way I use my carrier taskforces is to split them off from my main surface combatants with some escorts, set them to do not engage and use their CAG in the naval region in question on naval strike, seemed to get the job done prior to 1.5.1.
 
I'm not ruling it out that it shouldn't happen, but what I am saying is that carrier fleets that engage with enemy carrier fleets, never, not once, just sent all their BBs, CA/CLs, and DDs towards each other while they attacked from the air.

Aye, definitely - I fully agree that while it shouldn't be impossible, it wouldn't be consistent with actual combat operations during the war to model carrier fleets' surface forces engaging every time. I haven't seen the stream, but the DD doesn't say this will be the case (although it also doesn't say it isn't).

Axe99, this is in no way an attack on you. I'm just trying to raise the issue so people start talking about it, and for the devs to take notice.

Not at all - I fully encourage vigorous, robust discussions, and at no point was it a personal attack :). You clearly laid out the facts (which you got right) and made a good case. We agree in this case, but even if we didn't, if you have a case you think holds water, you should push it - all of us make mistakes, and you never know if you'll be the one to get someone else back on track :).

From what I recall, the German AI is hardcoded not to attack the Maginot Line.

This is a while ago now, but in a game as Belgium, I built up level ten forts to see what would happen, and Germany left me well alone. Even level seven forts around most of Czechoslovakia, as well as they take advantage of the terrain, can deter most attacks by the Axis. Not that I'm suggesting these are particularly fun ways to play - I was just kind of seeing what'd happen (and for Czechoslovakia there's a focus for that :)).

I'd have to disagree, a fair few times I've seen them push through the Maginot, I expect there are various factors that more often than not make them not willing to attack, though it remains a possibility.

Watch out for French troops leaving gaps in the Maginot, often when Italy enters the war, or Germany attacks the Netherlands and Belgium. The French sometimes redeploy their troops, and Germany can take advantage of this to nab part of the line. That said, with enough airpower and persistence, I'm pretty sure it should be possible to brute force it as well.
 
What roll will the fuel System play exactly? Will motorized units not be able to move anymore, kif you are out of fuel?
Good question. I'd guess they'd move really slowly, but that's just a guess based upon my knowledge of this and previous HOI games. I've never seen a unit that just cannot move. You also might be able to strategic redeploy it to get it out of there so long as there is a link to your lines.

does that army xp doctrine thingy work with naval xp and naval doctrines aswell?
I believe it goes for all doctrines.
 
You're posting (imo at least) some interesting ideas, but might they be better served in the suggestions part of the forums (if you haven't already)? I could imagine they'd be easy to miss in a long-ish dev diary thread.



I think it was at the Battle of Santa Cruz where the Japanese surface 'vanguard' force got very close to the US ships scuttling Hornet - but you're quite right in that there was never a proper surface and carrier engagement in the same battle. Depending on what the actual HoI4 battles represent (at the moment they go on for a quite a while, so they could be interpreted as representing a clash between carrier aircraft during the day then surface fleets at night - iirc at one point Marc Mitscher wanted to send his BBs off to engage the Japanese surface forces at night, during the Battle of the Philippines Sea - but was sensibly overruled or decided otherwise (can't remember which). So as far as I understand it, it's not implausible that it would happen, even if it didn't really happen in the historical WW2.

Thanks for the info, i posted something about island hopping as well as naval invasion(s) months ago in suggestions, till today 0.0 answers. Heres my solution for island hopping......[copy &paste my old post from suggestiions. Maybe its bad like hell or good, but in my opinion it looks more realistic. Lets try together an open discussion and finding a solution for the problem (many ppl have). If you dont like please show us YOUR solution.

---------------------------
Posted in suggestions Sept.2018:


Also i believe if you plan for example a naval invasion over huge distance the amount of transport vessels should rise X² (per sea region crossed) cause its not that easy. At moment its far to easy.

Maybe :

Number of transport needed = Y
Sea region crossed = X
Number of battalions = B
Support batalion = C
Number of Tanks, motorised infantry, cavalry (battalions,not the number of tanks and so on)...... = T

Y = (B+C+T²)*X²

-----------------------
new:

Of course it could be neccessary to adjust the formula a little bit but that would only be possible if integrated and tested ingame, i cant do that.

My newest opinios was to add wheater like this W= wheater 1=good wheather(summer), 1,5=spring,autumn 2=winter

Y =[ (B+C+T²)*X² ] * W

So if you plan a naval invasion from UK to China it wont be posible cause the number of transport would be some 10000, as in real. I really dont know if the dev team does changing anything at naval invasions yet. But if you play now it is possible to do such cracy stuff like invasions from USA direct to Japan and so on. With my solution you must DO island hopping otherwise the needed number would rise so massively that it would become impossible.

Thanks in advance for your help, and share YOUR ideas how to fix this problem.............by the way: Naval invasions are so complex that in real Allies planned about 1 year for operation Overlord the landing in France..............they needed around 5300 ships just for hopping from UK to france.........
 
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I'm not sure i'm missing something so feel free to correct me, Apart from fuel limitations what will stop players from doom stacking their ships.

Don't worry, they mentioned this in one of the dev diaries. There is a new statistic, positioning, which will be extremely low for doomstacks in addition to big org penalties. Low positioning essentially means that the fleet's capital ships will not be protected by screens, which combined with low org should mean that a small, but powerful and well organized fleet should, in theory, be able to inflict some crippling capital ship losses and route the enemy doomstack while taking very little losses or damage themselves. That's just assuming I've understood the mechanic correctly and that it's actually properly implemented!
 
This is just absurd. No excuse for this kind of delay. Even CA gave a nice explanation of why it took so long to implement Norsca into TWW2 and how it would throw off the content schedule.

What exactly has been happening for the past YEAR?

To add insult to injury podcat is acting as if its business as usual when under his direction Hoi4 has been outpaced by every other dev team at the company several times over.

No explanation, no apology, just releasing a multiplayer focused aar as if it was a fun extra right before release.

It's not hunky dory. There's no release date, not even a ballpark one. They've had all the time in the world.

If it was that jam packed with stuff then they wouldn't be putting out a boring aar between players. Nobody cares about multiplayer. It's a small fraction of the overall games. Yes I'm sure a bunch if people will say they like it but they are still in the minority.

At this point it should be clear that this expansion is not coming until the summer at EARLIEST. It probably will not be great either.
I understand being upset that the DLC has taken so long to release and I personally wish Paradox would take action to speed up the production of DLC content. They need to put more members on the team or do SOMETHING to help produce content quicker. Quicker, but still quality content, would increase profits a lot and I'm surprised the heads at Paradox haven't done anything to help the Hoi4 team get content out at, at least a relatively close rate to some of their other games at this point. The content we have been shown for this DLC looks superb so I have withheld complaints about production time, but what you have done is the wrong way to do it. Being rude and explicitly negative is not going to help anything or anyone.