[raketenjagdpanzer]

There's almost certainly a fair few combat aircraft remaining, perhaps a few dozen, in NATO hands. The French are capable of air combat operations over the German border (it's flat out stated in one of the modules), and of course a transport bird still flies off the deck of the USS John Hancock of TF34.

The question is down to use of aircraft, fuel, and munitions over target value.

A mass of 30 Pact tanks obviously getting ready for a major offensive push would merit using your last 2 F4 Phantoms and trio of A10s to try and take out. A band of Polish territorials of questionable allegiance and armed with an ASU-57 and four trucks, the rest walking or on horseback but possibly equipped with an SA7 'Grail'? A lot less so.

Since after the last battle in and around Kalisz, the WarPact forces hardly have the former, and it's most likely the latter, Tac Air is going to be scarce to non-existant.

As far as proportions of what might still be flyable, I think the RDF Sourcebook probably gives as good an outlook in terms of percentages. The US still has one carrier in need of repair moored in Kuwait, but a lot (relatively) of intact USAF birds (F15s and A10s, IIRC) and that's not to consider what the UK might have (probably the majority being SEPECAT Jaguars, Tornados, and Harriers - possibly even Buccaneers).

All in all the tac air situation is probably "less bad" than what you might think but it ain't good.