Question:
It seems almost impossible to take out enemy fighters if they don’t want to fight, since even inoperative ones can scramble. This seems too generous; fighters certainly did get caught on the ground from time to time; it is actually easier to overrun them with tanks! Perhaps they should have to make some kind of escape die roll in order to scramble?

Answer:
Inoperative fighters must be able to scramble. Otherwise, players would resort to the ahistorical tactic of waiting for enemy fighters to become inoperative and then immediately flying to bomb their airbases.

Source:
Errata published at http://www.hmsgrd.com/Files/Europa/Second Front/Second Front.pdf