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Pick a Motor

I'd love to hear your feedback on this feature. It's new and needs validation.

Use this form to quickly select a list of candidate motors and minimum ESC and battery recommendations  for you airplane. The input required is simply the weight of the airplane and the type of flying you plan to do. The goal isn't to provide a solution for every type of aircraft out there. There are too many types of airplanes out there to really make this work in a generic fashion. But if you have a plane that is advertised as being a trainer, sport, 3D flyer, etc, then chances are the approach outlined below can get close.

The approach the code takes is fairly simple:

1) If the user entered dry weight (no motor, no battery), then the dry weight is bumped up by 40% to arrive at an all up weight.

2) Watts per pound is determined, based upon the selected type of flying. From this, total power P is determined. Additionally, a target thrust T and pitch speed PS are determined, again based upon the selected type of flying.

3) From the wattage figure, a pack voltage is selected based upon packs that are commonly available today. For P<150W 2S is used, for P<275W 3S is used, for P<400 4S is used, for P<600 5S is used, for P<1000 6S is used.

4) ESC rating is P/ + 15%, where V is the pack voltage determined in step 3.

5) The pack capacity, in mAH, is P/V * 100. This will give about 6 minutes of flying at full throttle, which is usually 10-12 minutes of flying for typical pilots.

6) A database lookup is performed, given the V and P targets, to find all motors fitting those targets.

7) Given the target thrust T and pitch speed PS,every prop in the database is tested on each of the candidate motors to see which props will exceed the T and PS targets. When a first prop is found that exceeds the targets, that prop is noted and the next motor is considered.

You can hover over the labels below (eg. "Sedate" and "Sport") to see the targets for P, T and PS.

Suggested weight is 0.5 to 5 pounds

Airplane Weight (pounds)


Unlimited 30 degree climbs, 35-40 MPH cruising speed
Unlimited 45 to 60 degree climbs, 45 to 50 MPH cruising speed
Unlimited vertical at full throttle, cruising speed of 25-35 MPH
Solid vertical performance, but not unlimited. Cruising speed of 65 to 70 MPH on a clean airframe
Unlimited vertical performance at full throttle, hover at 3/4 throttle with 50 to 60 MPH cruising speed
Unlimited vertical, hover at half throttle with 40 MPH cruising speed
Hover at 3/4 throttle, with 60-70 MPH cruise on a clean airframe
100 MPH on a clean airframe. Unlimited 60 degree climb