HexaCopter with 5 or 4 motors


With the right PID and the right motor power, an Hexacopter could hold the drone with 5 or 4 motors (with 4 motors, i understand have to fail motors oposites)? .

I have seen fail one motor on one of my drone, and it hold it, but with other of my drone it didnt and starts spining until the motor recovered.

What do I have to be caution to be sure it can hold it?


It needs to be massively overpowered to fly well…

this is the log of the drone I have told you before flew with 5 motors, may be you can checkit and see what the drone did too well to stay in the air.

fallaMotor.bin (1.8 MB)

@robomatic - can you provide the motors/esc/battery configuration you are using? A Hex will absolutely be able to fly with 5 motors as long as they can make up the difference for the lost motor. I have personal experience with early DJI Naza-M V2s being able to handle this. I keep one switch position in Poshold and Super Simple mode for just this emergency on my Arducopter Hexas.

This is an older video by Marco Robustini who is pretty well known in the AC community: https://www.youtube.com/watch?v=peE7W6ZwT3k

Here is a github thread on the topic:

Hope this helps.


The Drone was able to hold has Arris 4010 motors, 2,2KG per motor full th.
ESC 30Amps (motor only draw 16Amp max, measured on my benchtable).
15x55 props carbon fiber
6S 20Amp, 10C discharge

The one couldnt handle well is:
Tarot Motors 5008, 340KV , 3KG per motor
ESC FlyColor 50Amp (motor only draw 19Amp max, measured on my benchtable)
18*55props carbon fiber
6S 22Amp, 10C discharge

There are some pretty significant differences between those builds. How exactly did the build with the 5008 motors not handle it well?

May be my PID wasnt setting very well?

About the weight distribution there was a big difference, may be could be te problem?

This is the one hold the missing motor

An this is the one who couldnt

As you can see, in the first one the weight is all in the middle, meanwhile in the second, the camera on the front, and the battery is compensanting the camera weight. May be that can be the problem? Or a bad PID setting?

The main question maybe will be in one of the PID is more related with the weight in this case, the P on the yaw?

Here is the video of the spinning, minute 3:57

I would expect the spinning in most cases. They key is being able to land safely after a motor failure, which it appears you were able to do. Review the link from Github from my previous post, in particular Tridge’s thoughts on the the AP’s configuration, and it may give you some idea of what to expect and what may help to mitigate motor failure.

The motor failure was detected after that, was a signal cable lose…

The safety landing in the video was becuase the motor start working again… if not,
would have crashed… I culdnt handle the landing until the motor start again…