I'm in Day 7 of a Balkans campaign. About 2 of every 4 missions I try to fly end up being cancelled because no pilots are available. I click Fly to launch and when the clock gets to 0 I get a pop-up indicating that the flight was cancelled.

When I select a slot in a given flight, the other ships show 'Not Assigned' (or 'not available' - I can't remember exactly). BARCAPS and sweeps seem to have pilots but the strike missions are the ones where the pilots are awol.

Is there something that I am doing wrong or is this just the state of my campaign? I'm assuming that I've lost so many pilots that I don't have enough for other flights. Any advice?