another crash today, seems that one motor stopped


Quad X, all up weight 4kg, apm 2.6 with ac3.1.2, external compass, MN3110 470kv, T motor esc 30 amp, 17*5.8 t motor carbon prop, 4s2p 5000mah.

i had a crash today, it sounds that motor 4 stopped, i was tunning my quad.

tunning : fly with radio, land, change pid on my computer with radio link, write, then fly again to test and do the loop again.

I unscrew everything and follow each wire from motor to apm and everything was good.

is the autotune issue with low kv a bug in the code or a thing that happens even in normal stabilize flights?

i attached the log if someone could give me clue.

what does mean : error check 1?


2014-03-11 13-29.log

2014-03-11 13-29.log.gpx

2014-03-11 13-29.kmz

You need to be a member of diydrones to add comments!

Join diydrones

Email me when people reply –


  • You didn't toggle Autotune while in the air did you?  That can cause an immediate loss of power.

    • no, i did before but as it is written in the wiki, my low kv motors make it crash.

      so i only do manual tunning now.

      • It looks like you built your copter as a heavy lifter -- powerful motors and big props -- it also looks extremely lightweight. Trying to tune such a powerful machine without a payload could make it behave unstable and overreact to your inputs. If that's the case I would add some additional weight as ballast until you're comfortable enough to hang your DSLR on it. 

        • thx,

          you are right, it could over react, i m already using a ballast wich is as heavy as my dslr.

          • If you don't mind my asking, what motors are you using and how much does your copter weigh all-up. Batteries plus DSLR, etc., and what size props are you flying with?

            • no prob,

              batterie 2*4S 5000maH =1100g

              frame+motor+props+gimbal : 2000g

              motor :t-motor mn3110-26 470kv

              prop : t motor 18*6 cf prop

              esc t motor 30A

              dslr :1000g

              all up weigh 4100g

              pictures bellow are not totally right as i upgrade motors props and esc from rctimer to t-motors.



              • Ah. I ran your numbers through eCalc and came back with the attached.  The results are just the opposite of what I expected.  I believe you are a bit overweight and over-propped for those motors.  

                I re-ran the numbers with aggressive 18x4 e-prop and a single 4S battery (up to 8000mA) and eCalc said that combination is nearly ideal.


This reply was deleted.


Laurie J. Troy liked Jasper Kueppers's profile
Apr 1
Timothy Miller liked Joseph Udofia's profile
Mar 18
Joseph Udofia liked Joseph Udofia's profile
Mar 3