I would prefer cash but I ' m willing to do doom and $ 5 PayPal or bitcoin for a copy <| sep |> You CAN theoretically set your airfields to evacuate and your airfields won ' t receive any damage so you don ' t lose any planes . Thus you don ' t lose any resources having to replenish your planes in your base but you ' re leaving the airspace wide open for enemy air raids . Now I ' m not sure whether the resources saved from not having to replenish planes is greater or smaller than the resources lost for the enemy air raid , but you can try testing it out yourself . I suspect it ' s not though and I recommend you to just have the interceptors and fill the rest with fighters and saiuns if you have some to spare you don ' t normally use like the zero type 21 s so you can get their ranks up to you need them for the monthly conversion quest which is quite useful . Up to you really .