Which aircraft to build first?

Why the fighter?

We build the fighter first for one goal — winning air superiority. This isn’t just a fancy word, it’s the most important air mechanic in HoI4: when the sky is yours, the enemy takes defence debuffs and your bombers and CAS planes work as they should.

Almost always — fighters first for superiority, and only then everything else. This rule comes from hundreds of campaigns, and exceptions are rarer than beginners think.

What happens without air superiority?

If we don’t have air superiority, chances are the enemy does. And if the enemy has it, a chain of trouble follows:

• Your CAS planes can’t work effectively — enemy fighters keep them away from the battlefield.
• Enemy aircraft freely pound your divisions and rear areas.
• Whatever your air force looks like, it doesn’t pay off: the factories spent on it are wasted.

Air superiority comes from fighters on the «Air Superiority» mission. No other plane type does this job better. And what happens if you still start with CAS?

Why it’s a dead end

Example: you invested in CAS planes — and then what? The enemy has fighters, and they effectively destroy your CAS planes. Result: you have CAS planes, but they can’t do their job because enemy fighters won’t let them reach the battlefield. At the same time the enemy opens a gap for their own planes, which in HoI4 is a huge minus.

A classic beginner’s mistake: seeing the big damage CAS planes deal to enemy divisions and building them first. Looks nice on paper, but in practice it’s sad: the sky belongs to the enemy, and your factories go to planes that just sit idle.

CAS planes only shine once air superiority is already yours. Until then, producing them is throwing factories to the wind.

That’s why strong players usually put CAS planes in a region only when there is air superiority.

When is it acceptable?

There are exceptions, and quite concrete ones:

• The enemy has no fighters at all — they physically can’t shoot down your planes, so CAS first is justified.
• An ally brings fighters — for example, in multiplayer a friend goes fighters while you build up CAS planes.

In all other cases the rule doesn’t change: fighters first, or you’ll get neither superiority nor properly working bombers.

For example, if you joined a strong alliance as a minor (Axis, Allies), you can produce mostly CAS planes. You bomb, and the strong allies (Germany, Britain, etc.) take air superiority. Good — but what to build after the fighters?

Second priority: CAS planes

As soon as air superiority is secured — bring in the CAS planes. They hit the enemy’s ground forces and support the offensive — and in HoI4 a fighter + CAS planes combo is often enough.

Third priority: the rest of the air force

Everything else — naval, strategic bombers, transport planes — goes last. They fully shine only under the umbrella of your air superiority:

• Naval bomber — sinks the enemy’s fleet and convoys.
• Strategic bomber — burns out the enemy’s factories and infrastructure.
• Tactical bomber — bombs both enemy divisions and buildings.
• Transport planes — airborne operations, supply by air.

The production order is not a dogma but a priority: in the first stage of the war, almost your entire air priority should be taken by fighters, and only then you start switching part of the factories to CAS planes.