Aerodynamic center- Center of pressure- Phases of flight

What are the phases of flight? Takeoff Climb Cruise Descent Loiter Landing What is aerodynamic centre? Aerodynamic center is the point in the aerofoil where the pitching moment is constant even though if we change angle of attack. To solve flight dynamics problem it is the pivotal point. What is center of pressure? Centre of pressure is the point where the pitching moment is zero. When angle of attack varies cop varies. So it is tedious if we try to solve dynamics of flight by taking COP as reference.