Control Surfaces 
- As with a flight control system, a guidance algorithm uses control surfaces to control the behaviour of an airframe. 
 
       - Rudder, ailerons, elevators, spoilers and canards for aircraft. 
       - Canards and fins for missiles.
- Each control surface has an angle, usually denoted by '. 
 
       - E.g. the canard angles are usually 'c, etc. 
       - The guidance law will generate a required acceleration, and a linearised airframe transfer function will be used to convert this acceleration into a value for the various control surface angles.      
- We will deal with these controls in more detail in a later lecture.