Recently, I took a long and hard look at the jet tank. What I saw was that flying controls and mechanics have taken a lot time, but have not progressed to a usable state. So, I decided to leave it for now, and move on to everything else. I will come back to flying tank later after the core of the game play is done.
Game logic. The first thing to tackle is a better missile - homing missile. You don't need to guess the arc of its motion anymore. You just point at the object you want it to go, and press/click fire. The missile homes in to the target, though it may miss if the object does something tricky, such as hiding behind an obstacle, or maybe shoot the missile down.
Once the homing missile is implemented, I will work on creating a crosshair for aiming, add ray casting according to the position and orientation of your camera. Then the whole missile feature will be done. You will able to aim and send homing missile anywhere you want them to go.
Though, I will have to add an option to a homing missile to simply go in some direction, if you missed everything on the map, such as clicked on the sky or something. I'll think about that. 8)