Vinkman, we had a nice fight the other night. I would recommend you try something other than the P39 until you get comfortable with Aces High, the ballistics on the 37mm can be a bit tough at times.
If you're dead set on flying the P39, let me know and I can provide you a target in the TA where the lead computer sight is enabled. After a few passes, turn it off or you'll start to rely on it. From then on, I'd recommend you work offline on the drones until you can 'one pass' them from any direction and at any speed.