






Enter the specifications of the model










Name of the plane 



mm 
Specify span 



dm2 
Specify wing area 



g 
Specify weight 




Specify a shape factor 



m/s 
Specify the required climb 









Recommended maximum wing loading for a combustion motor model 

g/dm2 


Recommended maximum wing loading for a electric motor model 

g/dm2 


Wing loading for configuration specified 

g/dm2 


Minimum sink rate 

m/s 


Watts required for level flight 

W 


Watts required for requested climb 

W 


Minimum watts based on 100W per kg rule 

W 


Maximum Watts required for takeoff 

W 


Watts required for adjustment of 1 m/s 

W 

W 
With this power the further calculations will be done 




Prop diameter (Minimum) 

inch 


Prop diameter (Recommended) 

inch 

inch 
With this propeller diameter the further calculations will be done 




Prop pitch (Minimum) 50% of diameter used for a dragger 

inch 


Prop pitch (Recommended) 

inch 


Prop pitch (Maximum) 90% of diameter used for a hotliner 

inch 

inch 
With this propeller pitch the further calculations will be done 









Name of the motor 



Ohms 
Specify Ri 



A 
Specify Iopen 



RPM/V 
Specify Kv 




Specify Pri (Maximum motor load) 



gram 
Specify weight of the motor 



A 
Requested nominal motor Amps 









Calculated number of cells 




With this number of cells the further calculations will be done 









Stall speed 

km/h 


Maximum speed (stall speed *3) 

km/h 


Rm required (WS figure out next formula!!) 

Ohms 


Output power 

W 


Prop RPM 

RPM 


Motor RPM 

RPM 


Gear ratio 




Select the proper gear ratio





With this selected gear ratio the further calculations will be done 




Based on the selected values the model will have the following performance










Corrected real prop RPM 

RPM 


Calculated real maximum
model speed 

km/h 


Calculated output power, corrected for selected prop 

W 


Motor efficiency. Some work to do to find out how to calculate at this stage 




Real current 

A 


Motor losses 

W 


Maximum motor current 

A 


Maximum Power 

W 


Input Power 

W 


Output Power 

W 


Efficiency calculated 

% 


Copper Losses 

W 


Iron Losses 

W 


Current for maximum efficiency of motor 

A 