• 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.