Hello guys. I have a problem. I have a t-rex 600 helicopter and a pixhawk px4 helicopter. When I change flight mode from stabilize to althold then the swashplate goes down to -3 degrees just like I have set the bottom range of the swashplate movement. The same happens in the loiter mode. Does anyone know what it is caused by? Can you help me?


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  • Hi,

    I did it that way, I changed pixhawk 1 to pixhawk 2. I had the same settings as before, and the problem in alt hold was no longer like pixhawk 1. I do not know what was the reason. It is possible that the version of the mission planner, but I do not have certainty. After many attempts to solve the problem, I gave up and changed the controller.


  • Hi Marcin,

    Did you get help feom anybody ? I have the same problem. When switching from stabilize to alt hold, the collective pitch decreases by 3-5 degrees.

    I searched all the parameters in Mission Planner, but can't find a relevant parameter. My set up is Align 450 flybar, Pixhack, Copter V3.5.7.

    I have another set up Align 450 FBL, APM 2.6, Copter  3.2.1. With this setup, the collective pitch does not change when I switch from stabilize to Alt hold. Cannot upgrade to Copter 3.5 becasue Copter 3.2 is the last version which supports APM2.6.

    Let me know if you have clue to solve this problem.



  • Here is the link to logs

    2018-07-10 12-45-43.bin

This reply was deleted.


Shivchand Jaysaval liked Shivchand Jaysaval's profile
Aug 25