How are you supposed to use subs?

[Riekopo]

I really don't understand how you're supposed to use submarines in this game. I was playing as Germany and within a few months of starting in the 1939 start date I lost almost all of my submarines to enemy fleets. I organized my subs into a large fleet and put them under the command of Donitz who has a 20% buff to submarine attack. I told the fleet to convoy raid three zones in the Atlantic. These are all logical and historical decisions.

However, the game mechanics do not seem to work right with submarines. My subs were wiped out in a few large naval battles that resembled surface ship battles. Then, as the fleet was retreating to its home base to repair the rest of them were wiped out. It seems to me that the game is treating submarines the same as surface ships and this is making them extremely weak and basically useless. There doesn't appear to be any effective way to use them with the current mechanics.

Another major problem I see with submarines is the game doesn't even give you a guesstimate of enemy convoy routes. So you are nearly blind and just have to guess where their routes are. The other issue is that even if you do sink enemy convoys it seems to have very little affect anyways. I don't think I've ever been able to cutoff the supply of resources or supply to my enemy. And there's no food so that's not even a factor.

 

[Zulgaines]

Beyond adding a few to my fleet mix I mostly us them to scout/convoy raid every sea providence. 1 In each area.

It works out pretty well.

 

[Dirk_Slamchest]

Putting all of your subs in one fleet makes them easier to detect. Historically, the German wolf packs contained less than 20 subs, I think.

You might have a point about subs being under-powered though. I don't even bother using them because they're so weak. I think the sea game would be much more interesting if they got some big buffs and the victim could specifically control their convoy routes and escorts per convoy.

On the other hand, historically the Americans could easily produce convoy ships faster than they were destroyed, so I don't know...

 

[actioncradd]

Split them all into single sub fleets. 1-2 per zone over every possible zone. The rest sit in reserve as replacement

 

[Hjaldrgud]

Let them rest in your dock until Paradox fixes them. They are useless steel coffins for your seamen

 

[DGuller]

I use them as tow boats for fleets that are short on range. Attach all your submarines to your fleet and it may just make it through the zone that used to be redded out.

 

[Sanny]

I use them to lure the enemy fleet out of hiding. At this point they are almost completely useless.

 

[him_15]

At the current stage sub is no use not matter which tactic you use, just ignore it completely until the sub mechanic is overhaul in the next DLC.

 

[Dalwin]

At the current stage sub is no use not matter which tactic you use, just ignore it completely until the sub mechanic is overhaul in the next DLC.

That is so completely wrong.

I literally get 100s of kills with my subs even in MP games.

The most important thing to remember is that putting them in a large group is the absolutely worst thing you can do. I put them in pairs or sometimes in groups as big as 3 or 4 but no bigger. Put them in areas where the enemy is less likely to patrol. Expect to lose some and have to replace them, but over time you will kill many convoys and a few warships. By the time you consider that some of those convoys were carrying troops, the subs are very cost effective,

 

[Axe99]

For the vanilla game, follow Dalwin's advice. It's a bit of a micro-management pain, and they play out rather historically implausibly (that's not a slight on you Dalwin, but the mechanics ) but it's the best way of managing a bad situation.

I've had a bit of a play in the mod I'm working on, and have had some success by toning down the chance of spotting subs with a patrolling fleet to very low (unless there's air cover of the area - so the channel can still be dangerous), increasing sub speed to somewhat ridiculous amounts (but while the speeds in terms of knots are ridiculous, it actually results in a more 'natural' sub game). Some examples (taken in order in the GER game I'm playing through, so I'm not just cherry picking the 'good' ones, I've just grabbed the eight most recent screenshot examples I've taken) are in the spoiler below - but it is possible to mod things to get more rewarding sub gameplay (but I haven't found a way to not have subs destroy all of an unescorted convoy yet, and it's still a bit brutal - as at 7 Jan 1940, it was a tally is 32 U-boats lost for 14 ENG DDs, 3 FRA DDs and 2 FRA CLs, plus convoys (historically the Germans lost 24 u-boats up to May 1940, although I started with many more u-boats for the Allies to sink than the Germans did, and may need to tone down submarine detection of surface fleets a bit).

Anyways, just mentioning it as I know it's a source of frustration (indeed, I hadn't planned to look at subs until later, but I got tired of the sub stackwipes, patrolling DDs finding them too easily and escorted convoys being more-or-less immune, and had a look at it). The mod's not out yet (the first stage is historic stats for the ships in HoI4, and I still need to do the USN - and the plan now is to combine it with @Balesir's excellent Waltzing Matilda prior to release as well) but if anyone else wants a "it works but is missing historic stats for the USN" version for a somewhat improved sub game, send me a PM. Keep in mind the sub game is still a ways from where I'd want it, and I'm in the early stages of playtesting (it's had lots of controlled tests, but this is my first game with it in the general course of play) but I'd feel bad having something that I'm enjoying a lot more without making it available for others in the off chance it'd help. Of course, if the results in the spoilers below don't look any good to you, I'd recommend avoiding it like the plague .

Spoiler

 

[Zarine]

The main problem is that sub should disperse as soon as there are detected/engaged but it's not at all what they are doing.

Only solution yet is the small packs tactic.

 

[mabus81]

I know this is offtopic, but when playing Germany I resort to researching carrier II immediately and then invest all my dockyards into construction. I also put 5 MIC into constructing carrier naval bombers in early 38. That way, you will have 3 operationable aircraft carriers by october 1939. Puts you into a position to launch Seelöwe so early that you even might get peace for a couple of months (until the american AI starts justifying a war goal against you, anyway)

 

[smurfopax]

Set them on do not engage. When they find convoys they try to sink it, but when there is only one destroyer they flee. That combined with small 5 packs works out pretty well in my opinion. But subs start to shine when you have researched Sub III. You will see a huge increase of usability with the usage of Sub III.

 

[Zarine]

Set them on do not engage. When they find convoys they try to sink it, but when there is only one destroyer they flee. That combined with small 5 packs works out pretty well in my opinion. But subs start to shine when you have researched Sub III. You will see a huge increase of usability with the usage of Sub III.

Wait !
If I put them on "do not engage" they will engage convoy but not engage fighting ship ?!
That seems to be the way to use them.

 

[smurfopax]

Need to test it again. But

This toggle switches between ‘Fire at will!’, where the fleet will engage any hostiles it encounters and ‘Do not engage’, where the fleet will seek to avoid combat. It's worth noting that fleets that are assigned orders should not have ‘Do not engage’ selected, otherwise they will simply run every time they encounter the enemy. Also, fleets assigned a specific order such as “Convoy Raiding” will not try to engage enemy warships on patrol, even if their Rules of Engagement are set to ‘Fire at will!’ but instead they will prefer to sink convoys.

I'm not 100% sure. But i always set my Subs to "Do not Engage" and they sink convoys. Need to check again, i don't look at Naval Combat before i'm engaged with Russia (when playing Germany)

 

[Landsturmamrika]

I just played a game as Communist Yugoslavia and sunk 2 Italian Battlecruisers with basic level 1 submarines grouped with my surface fleet. For the amount of industry dedicated to those 2 heroic submarines it seemed well worth it from my point of view. I'll have to experiment further.

 

[Galithor]

I've seen submarines used to devastating effect in some recent multiplayer matches in tandem with tactical bomber's newfound Naval Strike capabilities. Subs find big convoys, and they murder them a whole lot faster with the TAC support, which can cover a whole lot more sea zones critical to allied shipping than CAS can cover. The US and UK reliance on convoys have never been more vulnerable in the multiplayer meta than they are right now. Like, devastatingly vulnerable. Singapore folding like a cheap tent because the defenders are de-organizing on their own due to lack of supply. D-day failing before it gets started because the allies simply can't supply it even if they manage to put together enough convoys to launch it. 90% of allied dockyards on convoys, and all of them dieing within days of construction while their fleets are steadily whittled down by hundreds of Axis Tactical Bombers in dozens of sea zones preventing them from really countering the submarines raids.

I've seen some really good UK and USA players just get mauled by this recently. The commonwealth minors simply giving up shortly after it becomes obvious they'll never be able to move anything anywhere ever again for the rest of the game. The soviet player simply with no hope of actual relief from the allies.

Subs have never been more useful than they are right now.

 

[Secret Master]

By the time you consider that some of those convoys were carrying troops, the subs are very cost effective,

There is also value in delaying troop transports even if the troops survive.

Last time I invaded Japan in MP, IJN subs trapped some of the invasion forces sent to Honshu in convoy battles for weeks. The Allies still got a foothold, but the delays cost us valuable time. And had another landing force been delayed in combat, we might not have even secured a landing.

We didn't lost hardly any troops in those convoy battles, but divisions sitting in convoy battles can't do anything else.

 

[Louella]

I have found that submarines are a bit more useful when playing as the UK, than they are when playing as Germany. UK submarines set to convoy raiding on the Demerara Plain, off the coast of America, and in the Indian Ocean, can stop a huge amount of Germany's trade, and there is nothing that Germany can do to prevent this, as they lack sufficiently long-ranged ships or aircraft to provide cover.
In the reverse situation, there are a few gaps that German submarines should be able to choke the UK's trade, but the UK and subjects have much better air and naval base coverage, and can get destroyer forces in to cover trade a lot more easily.

 

[Dalwin]

I've seen submarines used to devastating effect in some recent multiplayer matches in tandem with tactical bomber's newfound Naval Strike capabilities. Subs find big convoys, and they murder them a whole lot faster with the TAC support, which can cover a whole lot more sea zones critical to allied shipping than CAS can cover. The US and UK reliance on convoys have never been more vulnerable in the multiplayer meta than they are right now. Like, devastatingly vulnerable. Singapore folding like a cheap tent because the defenders are de-organizing on their own due to lack of supply. D-day failing before it gets started because the allies simply can't supply it even if they manage to put together enough convoys to launch it. 90% of allied dockyards on convoys, and all of them dieing within days of construction while their fleets are steadily whittled down by hundreds of Axis Tactical Bombers in dozens of sea zones preventing them from really countering the submarines raids.

I've seen some really good UK and USA players just get mauled by this recently. The commonwealth minors simply giving up shortly after it becomes obvious they'll never be able to move anything anywhere ever again for the rest of the game. The soviet player simply with no hope of actual relief from the allies.

Subs have never been more useful than they are right now.

Land based planes can now launch multiple strikes within a given naval battle (just as carrier planes can) instead of only being limited to one strike per battle. This means that subs in certain areas where they can be supported by land based aircraft can be particularly deadly and even dangerous to the ASW fleets themselves. One key such area is off the Norwegian coast since all LL to Russia takes that route as well as resource trade to or from Russia.