APM 2.9.1 Alt-Hold (Scary!..)


I just set up my APM board for a quad. I flew a few times already in stabilize mode and it seems working just fine. Today, I wanted to try the "Alt-Hold" mode. 

I have read here a few times that the board has a tendency to shoot off when alt-hold is engaged. Knowing this, I wanted to test it. I raised the throttle (in Stabilize mode), till the craft gets to a hover. (I was holding the quad). I flipped the switched to "Alt-hold" and as I guessed, all 4 motors started running at full power till I flipped the switch back to stabilize mode.

I did it a few times with the same result:( 

Currently I didn't do any PID tuning. I flew the quad for about 30 minutes total. It is holding the heading pretty well. Responses are good. It hovers almost at mid throttle. But alt-hold is scary!!!

What should I do? I cannot even try the Loiter if I can not fix this issue.


P.S. Did the "altitude" test in CLI window. Did not get any negative value...

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  • I am having altitude issues. Are you running telemetry? Can you tell your altitude when in the air? Does it seem right? Maybe these issues are related!

  • Why is my thread still under "Unassigned" category?

    Is it not clear that it should go to APM 2.x (Multicopter) section?

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Shivchand Jaysaval liked Shivchand Jaysaval's profile
Aug 25