Keep loosing my airplane divisions

[Double A]

Im pinning the brits down to stop them from hitting my IC with bombers, but I keep loosing entire divisions of airplanes:S
When I make out my orders, I tell them to stop their ops if they get below 50% str/org.. the strenght part is their "numbers" right?
then why do they keep attacking when they have like 10% left?:/

 

[Yushal]

I've never been able to make this work. What I do is set them to defend by day only, and prioritise them for reinforcements. This lets them recover during the night. Also, you ought to check them every two weeks or so in the Airplanes box (top left button) to see which may need to rest awhile.