[Mobhack]

The only valid missiles and weapons for fixed wing air are the ones that are specific air weapon classes. One reason being that aircraft use the AP ammo number as the weapon (cannon) multiplier and do not use the HEAT slot either. So air guns have to have a larger HE PEN than usual if they are anti-tank guns. Air missiles with HEAT values use the HEAT pen on directly hitting a target IIRC, HE PEN otherwise including any collateral damage hits.

None of that really matters if you put the weapon on a ground vehicle, though it likely will not work for e.g. an over long minimum range for ground use. About the only air weapon that is used is sometimes an HNG for air is used on a light tank (though that may have been fixed in the OOBS, IIRC seeing it on some Italian WW2 tankette years ago?).

If the plane has a missile and can do a stand-off attack then it attempts that and only comes on for a direct attack once the stand-off weapons are expended (usually, I have seen them come on map after failing to get a solution). That could mean that a wild weasel aborts if it cannot find AA weapons with a radar to launch on, but at least you then know that there are no radar aimed AAA or SAM.