Missile code?

[Killerzeron]

EDIT: Now i made up a missile code...but for now, i got a new doubt. It's below on my plans.

now i know that i need a list if i want my missile to hit the tgt.


Plans:

1) Now what i am gonna do is add a circle , which will act as a range. all missiles will be like a homing missile (just making it a easy flight sim version) so you dont have to wait for a lock on and launch the missile. Now what i need is....the confusion with my if/else. Suppose that i put in all my missiles as a list, so if any of the world's object are in this missile, then the missile can turn and hit the object that was in it's circle. I am confused, i tried using the if () is within () of object then....
Does anyone know how to do this?? i am just so confused....


2) help on this:

i just need some help actually, on the speed one, not using the spacebar for speed, but using the ctrl to move at a constant speed, so what i need help at is that i just want that when i hit the ctrl button the plane moves at the constant speed,but when i hit it again it stops moving.

3)