Problem with AltHold / PosHold - dropping altitude!?


i have a strange problem with my copter: it flies just great in stabilize mode and it stays on point pretty ok when using poshold. Now the strange thing: whenever i have it in poshold or alt hold and move the copter in any direction it will drop a lot of altitude! 

I first realized problem, when trying to do autotune: i does start autotune, but soon drops so much height, that i have to quit and get it back to altitude by going back to stabilize. 

The Software i am using is: APM:Copter V3.4.2-rc2 (179a7f57). The first time i realized this Problem was almost a year ago but with Firmware 3.3.2. But i had so much other stuff to do so the copter was just laying around...

The hardware is a Pixfalcon. The copter itself was used before with a Pixhawk and flew extremely well.

If someone could please look into the logfile and direct me to any direction where this Problem could come from? (

Thank you so much!!!!

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  • Fixed IT: good old Vibrations... ;)

    What i habe done:

    not using the provided gel pads anymore. Now using tiny rubber balls and added some weight to the Pixfalcon (Receiver, ppm Converter, GPS)

    New Props (aeronaut CAM carbon light)


  • Any idea would be just awesome!! Thank you so much!

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