[quote=@Bright_Ops]
[@Aristo]

To answer your question, traits like Controled Flight and the trail that allows the walkers just means that your nation can produce those sorts of things. You can't really make a dirgible in a timely manner if your people had no idea how to make an airship fly in the first place after all.
[/quote]

But traits as written just seem so redundant: Controlled Flight's effect states "allows you to field dirigibles." Great, I have the know-how to make balloons, and presumably use them for war. But to actually field dirigibles you need "Dirgibles" - "allows you to field an air force." 

You'd think that if you had the knowledge to make them in the first place, you could make an air force out of them. 

Also, you pick a 'type,' like "They Shall Fall." Great, you can start with 60 interceptors. But then you have to go and spend another point to add interceptors to the 'flight unit' list. It's redundant.