Enter the aspect ratio of the wing into the Oswald Efficiency Factor Calculator. The calculator will evaluate the Oswald Efficiency Factor. 

Oswald Efficiency Factor Formula

The following two example problems outline the steps and information needed to calculate the Oswald Efficiency Factor.

e = 1.78*(1-.045*AR^{.68})-.64

Variables:

  • e is the Oswald Efficiency Factor ( )
  • AR is the aspect ratio of the wing

How to Calculate Oswald Efficiency Factor?

The following steps outline how to calculate the Oswald Efficiency Factor.

  1. First, determine the aspect ratio of the wing. 
  2. Next, gather the formula from above = e = 1.78*(1-.045*AR^.68)-.64.
  3. Finally, calculate the Oswald Efficiency Factor.
  4. After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

aspect ratio of the wing = 13

e = 1.78*(1-.045*AR^.68)-.64 = ?