A drag polar, also known as a drag coefficient curve, is a graphical representation of the relationship between an aircraft’s lift coefficient (“Cl”) and its drag coefficient (“Cd”) at various angles of attack. It is a fundamental aerodynamic concept that provides valuable information about an aircraft’s performance characteristics and efficiency.
- CD is the total drag coefficient of the aircraft.
- cd is the zero-lift drag coefficient, which represents the drag when the aircraft is producing zero lift.
- CL is the lift coefficient, which is a measure of the lift generated by the aircraft’s wings.
- e is the Oswald efficiency factor, which accounts for the deviations of the aircraft’s lift distribution from that of an ideal elliptical wing. It quantifies the efficiency of the aircraft’s wings in producing lift.
- AR is the aspect ratio of the wings, defined as the square of the wingspan divided by the wing area.