Aircraft vulnerability

[Snowbart1943]

As you gain aircraft technology, and lets say your opponent remains at zero, so now there's a chance you can shoot his planes down if you engage in combat. But, since he's at zero aircraft tech level, are your fighters invulnerable?

Anyone know if the French AI researches aircraft by default? The Russians, British? [:D]

[SMK-at-work]

Yes you are invulnerable if the enemy doesn't research a/c. 
 
the AI does research a/c 'cos I've had a few of mine shot down recently!  Aircraft research is per side, not per natinoality, so it only takes 1 nation to be inputing research for each side.

[Snowbart1943]

Oh, i shouldnt have known that, thanks!