Zero-lift drag coefficient

In aerodynamics, the zero-lift drag coefficient C D , 0 {\displaystyle C_{D,0}} is a dimensionless parameter which relates an aircraft's zero-lift drag force to its size, speed, and flying altitude. Mathematically, zero-lift drag coefficient is defined as C D , 0 = C D − C D , i {\displaystyle C_{D,0}=C_{D}-C_{D,i}} , where C D {\displaystyle C_{D}} is the total drag coefficient for a given power, speed, and altitude, and C D , i {\displaystyle C_{D,i}} is the lift-induced drag coefficient at the same conditions.

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