RC Aircraft Thrust-to-Weight Calculator

Thrust-to-weight ratio (T/W) is total static thrust divided by all-up weight (AUW), both in the same units. A T/W of 1.0 means the motor produces exactly enough thrust to sustain hover or level flight. Anything below 1.0 and the aircraft cannot fly under full power.

T/W = total static thrust (g) / all-up weight (g)

For a multi-rotor, total thrust is the sum of all motor/propeller combinations at full throttle. For a fixed-wing plane, use the propeller static thrust figure. Note that in-flight thrust is lower than static bench numbers — sometimes 20–30% lower at cruise speed. Build in that margin.

Benchmark ranges: Under 0.8: underpowered, may not fly at all 0.8–1.0: gliders, powered sailplanes, very slow fliers 1.0–1.3: trainers — stable, forgiving, good for beginners 1.3–1.8: sport fliers — responsive, capable of basic aerobatics 1.8–2.5: aerobatic aircraft — loops, rolls, inverted flight Over 2.5: 3D capable — hover, harriers, extreme agility

For a first plane, aim for 1.1–1.3. Higher T/W means faster and twitchier, which punishes mistakes during landing.

All-up weight must include everything: airframe, motor, ESC, servos, battery, and receiver. Weigh the finished aircraft on a kitchen scale rather than estimating. Motor and battery weights vary more than beginners expect, and being off by 50g can shift T/W enough to change the flying character.

Multi-rotor specifics: stable video quads typically run 2:1 to 3:1. Racing quads run 6:1 to 10:1. FPV freestyle is usually 4:1 to 6:1.