For jet driven aircraft , the thrust to weight ratio to meet FAR 25.121 One Engine Inoperative, Approach Climb requirements is plotted using the following relationship:
The lift coefficient is found from:
Th e drag coefficient is calculated from:
The zero lift drag coefficient during approach is dependent on the value of the change in zero-lift drag due to approach:
The 'B' of the aircraft drag polar is calculated from:
See Matching Plot Guidelines: Jet Driven Airplanes
For propeller powered aircraft , the weight to power ratio to meet FAR 25.121 One Engine Inoperative, Approach Climb requirements is plotted using the following relationship:
The lift coefficient is found from:
The Drag Coefficient is described above.
See Matching Plot Guidelines: Propeller Driven Airplanes
Note: Equations used in this topic assume the British unit of the parameter used in the program. For the SI unit system, appropriate conversions must be made.