Iris lands badly by itself

Strange end of auto mission today.

I wanted to trig the battery failsafe at 10.5V and check reaction while Iris+ was loaded with a 250 grams camera. So I gave him a mission with 18 very close parallel lines, 200m long.

When turning for the last line, sudden lost of altitude while telemetry was still given 10.8. And finaly badly land and flip over. One of the last turns I saw also a lost of altitude, but Iris recovered.


Battery log shows no error, but I observe a lot of max values for ThrOut. Max throttle did not keep Iris in the air.

3691181652?profile=originalNot even a crash event was logged

Only change I made from previous satisfactory config is update to 3.2.1 and EKF enabled.

Any idea of what happened ?

I put log in next post

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

Join diydrones

Email me when people reply –


  • Based on the log of the motors it was too heavy to keep it in the air.  Motor 3 was pinned both times it lost altitude.


    • 3702549622?profile=originalparameter comparison between previous values (in the "new value" column) when Iris was flying correctly. Any of these discrepencies can cause the misbehaviour ?

    • Thanks for your answer Michael

      300 gram with support being too heavy for Iris+ ?

      The point is that I used to fly like this before without problem. Having a problem on motor 3 only can be a calibration issue ?

      BTW, the motor 3 activity indication is RCOU / Chan3 ?

      • Right, upper left motor.  They all clamped at 1950.

        The IRIS is rated at 400 grams so don't know why it had a hard time.


  • the log file

    2015-02-19 15-27-52.bin

This reply was deleted.


Liam left a comment on Agricultural UAVs
I'm Liam from T-MOTOR. I would like to reach out to see if there is any possibility for us to work together.
We are a propulsion system manufacturer who offers motors, propellers and ESCs for all kinds of drone applications which vary from secur…"
Jun 30
Richard Cox left a comment on Australia
"Anyone in the DIYDRONES Australian subgroup based in Alice Springs, NT?
I am experimenting with Ardupilot (standard Arduplane), Pixhawk 4 FC in a 4-ch
RC "AXN Floater Jet" foamy plane..."
Jun 29
Omar Sykes left a comment on Australia
"Hi everyone, I am looking for someone who is good at drone building, repair and software in Adelaide. Please give me a call on 0477 319 219."
Jun 29