aircraft entry and exit directions

[codman]

Looking for some advice about keeping my spotter planes alive. I've noticed that even when I set the direction arrows at the begining of the scenario, the fools sometimes decide to fly straight across the map and I suddenly find that the bad guys have enough AA to knock down the 8th Air Force. Perhaps it's a hidden default but I know I don't send them down the middle as I like find out just what's going on behind that wall of smoke and flame.

Thanks in advance