195, Route de l'Aviation
ZI Aérodrome de Sisteron
04200 VAUMEILH - France

The best way to reach our team is by email : helices@e-props.fr


Propeller Efficiency Calculator

The following program calculates the efficency of a propeller according to some parameters.
This program does only apply to the carbon E-PROPS propellers, with their specific profiles and their fine chords.
Those values cannot be reached with other propellers.

Replace the values given for example with your own data, and click on button CALCULATE : you obtain the efficiency of the prop and the speed on the blades' tips.

Be careful :
- the decimal sign is the point (.)
- the engine's power must be a real power (not a "commercial" power)

  Diameter of the propeller : meters
  Number of blades :
  Engine speed : RPM
  Reducer ratio :       (direct drive engine : reducer ratio = 1)
  Engine power :

  Flight speed : km/h
  Air density : kg/m3     (1.225 kg/m3 @ see level)





Thrust : Newton kg

Speed of the propeller slipstream : km/h 

Diameter of the propeller slipstream : m 

Torque : N.m 

Absorbed power : Watt

Usefull power : Watt

Peripheral Mach : Mach
=> do not exceed 0,65 Mach or the propeller would be too noisy

Efficiency : %



This simplified modelization allows a first approach for information purposes. It does not take into account the mechanical aspects imposing on blades a certain geometry. It calculates the propeller's efficiency at a specified point of functioning.

This modelization is precise @ + / - 5%.

E-PROPS engineers realize more pushed calculations and more detailed analysis to define the aerodynamic geometry and the mechanical behavior of the blade under load, as well as the precise performances in the various points of functioning. The LmPTR© software has been finalized in this purpose. Every E-PROPS propeller is realized for a specific configuration and engine, and naturally according to the pilot's specifications.

E-Props does not offer propellers with diameter less than 115 cm.


English Francais
Fixed Props for engines 7-50 kW dia 115 to 160 cm
Adjustable Props for engines 50-115 kW dia 145 to 205 cm