Now, its interesting.
A couple thoughts:
-there should be a reward if the mission succeeds, lets say, 15 perks for everyone, or a +50% to the country-wide perk bonus for a while, etc etc. Otherwise it has no weight and gives no motivation.
-if this thing is about to discourage hordes... usually hordes appear when a large majority of a country is "working" on one airfield. There should always be 2-3-4 from theese type of missions, what can spread out the horde. 20 people are more than enough to capture a base, they will very soon realize its more effective to have 3*20 capturing 3 bases than 60 shutting down one. This can create smaller fights.
-it has its downsides too. It may be common (can it be even more common??) to just flatten the hangars then horde it down. Consider it carefully plz, that wont encourage fights, more vTARDism is the last thing we want to see, right? (only one goal in front of them, you know what im talking about... zombyism)
-and one more thing, if theese missions are announced on both sides in the same time, by the time the attacking mission gets there, there will be 25K tempests waiting for them... not fun either.
As for the AI pilots.. NO, NO, NEVER!
Not a bad idea, just needs some tweaking. Keep in sight, youre paying for this, no friggen one has the rights to tell you which base you have to attack.
Also it can create a(n even more) mission-orientated game instead of a furball-orientated one, so be very careful with theese ideas, please.