Hunter Time

[ChuckMajik]

Are there campaigns for add-on aircraft out there?

Can't say I've looked.
I played the default campaigns, then just starting playing single missions.
I haven't touched a campaign since.

[Wing Nut]

Looks like a nice game.  What are the default planes?

[Tequila Sunrise]

stock
F-100D
F-104G
F-4 B,C,D,E
A-4 B,C,E

there are also mods to allow you to fly the Mig-17,19 and 21, Su-7, An-12, TU-18, TU-22, C-130 and B-57
not to mention a load of add on birds, sch as F-105, F-15, F-16, Vampire FBmk5, Hunter, Mirage III, U-2, F9F-2, F-86, F-89, Su-15, SU-17, Su-11, AV-8C, FRSmk1, Fmk 2 Harriers, A-7, F-8, Saab Draken, F-5, Banshee, Mig-15, Mig-29, Mig-23, and loads more I can't remember  8)