Hearts of Iron IV Guide | Navy Tips & Tricks

Hearts of Iron IV navies are a piece of work; there are quite a few things that pertain to them, and all these little things add up to make it seem extremely daunting, even when it might not be the case. This guide will help you understand some of the more important things to consider when dealing with navies.

However, please do not treat it as a guide that goes in-depth into things. It will also generally avoid numbers. That being said, here are some of the things to help you get better with your navies.

Naval Organization

In Hearts of Iron IV, the navies are organized into groups of ships called Task Forces. Up to 10 of these Task Forces form a fleet, which can be commanded by an admiral. Each Task Force can perform a separate mission; however, all Task Forces from a Fleet are assigned to the same naval regions.

Missions

Now, the missions that the Task Forces can be assigned are very specific, and the ships will focus on those tasks and nothing else. These missions, briefly, are:

• Naval Exercises: The Task Force trains in the open sea. They level up, gaining damage and giving you Navy XP. However, it costs fuel, removes all their organization, puts them into the sea, and damages them.
• Patrol: The Task Force actively searches for enemy ships. You can determine engagement rules to either make your task force keep observing detected vessels or engage them.
• Strike Force: Your Task Force stays in the harbor and only deploys when an enemy fleet is detected. Once detected, they attack the enemy and also grant naval superiority.
• Convoy Raiding: Typically reserved for Submarine Task Forces, this TF attacks enemy convoys only.
• Convoy Escort: The opposite protects your convoys against raiders. Best performed by destroyers and light cruisers.
• Minelaying: Again, it is typically done by minelaying destroyers and subs. It grants naval superiority and aggressively reduces enemy ship speed.
• Minesweeping: Makes the Task Force remove mines, negating their effect
• Naval Invasion Support: Escorts convoys carrying troops and supports them when they are landing through shore bombardment.
• Hold: Makes them stand still in their current location. When at sea, this gives them shore bombardment.

Naval Supremacy

A note for naval invasions is that you need 50% Naval Supremacy in the sea zones where your units will pass through. The best way to remove enemy Naval Supremacy is to ensure there are no enemy ships left there.

There are a lot of things going into Naval Supremacy. However, the most common factor is the number of ships in active missions there, namely Patrol and Strike Force. Then, if there are minelaying operations going on and finally, air supremacy

Admirals

You should always keep an admiral up and running your fleets, even if you don't have a good match. The Admirals have four main stats. Attack, Defense, Manoeuvring, and Coordination. Each level increases hit chance and coordination. 

The rule of thumb is that the largest fleets win, and having higher Attack and Defense increasingly makes your large fleets win harder. For very aggressive fleets, having a higher attack is important, but for more all-rounder fleets, having both attack and defense is important.

Another thing to consider is the admiral traits, which can affect many things to a large degree. The best traits are like Concealment Expert, which gives you lowered visibility and makes it harder to hit your ships. It also makes your ships harder to spot. Overall, it is the best for all types of fleets. Bold and Tactician are great for Patrol and Strike Fleets as they give 5% damage, 10% extra speed, and 25% bonus positioning, respectively.

If you are running a fleet in specific waters all the time, the terrain traits are great, especially Blue Water Expert in the Atlantic or Pacific. If you are running a fleet of submarines, Sea Wolf, Silent Hunter, and Loading Drill Master are the best, with Sea Wolf being the absolute best.

Ship Designs

Overall, ship designs have a bunch of things to keep in mind. This is, of course, if you have Man the Guns DLC bought and enabled. The main thing here is to keep a balance between cost-effectiveness and quality. So you want cheap and good instead of, for example, weak and many.

Refitting is always cheaper and better than creating new ships. And with major nations, you'll rely on the bulk of your existing Navy. You should always refit your ships once you have acquired the prerequisite techs. It also keeps things cost-efficient. However, avoid this with armor and engine designs as they are not as cost-efficient.

Destroyers

For Destroyers, you should aim to make them as cheap as humanly possible. Their main job is escorting capital ships and convoys and having high amounts of Light Attack. So, look for modules that make it fast and keep lots of light batteries on them. Torpedoes are a choice if you generally have more ships than them, but light batteries are always preferred.

Light Cruisers

Basically, the same applies to Destroyers: You want them to have a big focus on light attacks and be able to serve as a battle line. They are supplementary to destroyers but offer a lot of value. If you have the means, you should also get some armor on them, which makes them very effective against destroyers. It needs to be done very fast, just like before.

Heavy Cruisers

Stepping back and into Capital Ship territory, Heavy Cruisers are basically the best ships you can ask for. They are your ideal ships as you want heavy batteries as well as a lot of light batteries, serving as the nails that take out enemy screens. You should also keep them properly armored but keep them fast enough to keep up with aircraft carriers.

Aircraft Carriers

Speaking of which, for Aircraft Carriers, specialization is your friend. So, make them have a lot of deck space. Add anti-air guns as needed, but don't bother with heavy armor. They also need to be fast, like, really fast.

Battleships & Battlecruisers

On this front, you have two options: Battlecruisers are basically supposed to be faster and cheaper battleships that are versatile in their tasks and can both protect carriers and support big battles. They need to be fast and have a lot of anti-aircraft guns.

Battleships

Being the most expensive means that they are rarely cost-effective. However, to lean towards that, you need to get them mainly heavy guns and advanced armor. For guns, three is the best amount. Once you unlock it, dual-purpose secondary guns are invaluable since they provide utility against both planes and light ships.

Overall, you want your screens and heavy cruisers to be very cheap with decent stats, whereas you want your Battleships and Battlecruisers to have high stats and be relatively expensive because of their ability to win battles.

Tips & Tricks

Fuel Efficiency

Fuel is a hard thing to manage when there are a lot of ships, so rely on small patrols and large Strike Forces instead of having entire fleets on Patrol. Similarly, have a few destroyers on convoy escort and keep a highly reactive and mobile strike force composed of heavy cruisers, battle cruisers, and screens. For training, you should train the subs first, then destroyers, and then Capital ships because they consume the lowest fuel in that order, and they still keep up a high rate of gain on XP.

Composition and Positioning

Keep your submarines in small stacks of 10-20 and under a separate admiral from your normal ones. Keep your strike fleets into groups of 4 carriers if you get many carriers. Patrols should always be composed of ships with high spotting and speed.

For convoy escort, ensure your destroyers have depth charges and are under a separate admiral. Always have fighters up for spotting and naval supremacy, as well as ensuring enemy naval bombers don't wreak havoc on you.

Priorities

Lastly, remember that the Navy should get the fewest priorities. This is because, overall, they are the least impactful while consuming the most resources. This doesn't only include creating them, as you need lots of fuel to sustain them—fuel that you probably need to buy from somewhere, which consumes civilian factories. It's always about opportunity cost.

Check out our Hearts of Iron IV: Götterdämmerung DLC review and other guides below:

• Hearts of Iron IV Divisions Guide
• Hearts of Iron IV Guide | Division Templates
• Hearts of Iron IV Guide | Console Commands for Modding
• Hearts of Iron IV Guide | Naval Doctrines & Spirits