Problem in Loiter and Auto

Hello everyone.

I have a quadcopter and it flies in stabilize or acro mode so good, but in loiter or auto mode it flips. The motors are spinning different in those modes. Motor rotations and order are true. Props are true. GPS seems good. What could be the problem and how can I fix it?

Thank you.


Thanks for using AP. Could you include an onboard log file?

2021-07-15 16-20-43.tlog (672.5 KB)


ok, not a tlog but a .bin file. This can be downloaded from the autopilot. Please check the link I posted above, txs!

The file was so big. Therefore I share a drive link.

Can you reach the file @rmackay9 Is this a true file ?

Thank you for your help.

@rmackay9 I am so sorry I have uploaded the wrong log and I just noticed it. Now there is the true one in the same link. Sorry for that. Can you check the new file? Thank you.

that file needs access granted, see if you can open it up to everyone

Thank you for warning @xfacta . I opened it to everyone. Can you access it now?

I see no evidence that this craft is “flying good” in this log. It barely flying.

Other observations:
You are on default parameters and have ignored the Initial Pre-flight Tuning Parameters.
You have no battery logging.

Describe the components on this craft and it’s Take-off-weight with the battery.

Upload a log and I’ll take a quick look also.

The log is there, it’s what the graph was created from… It’s a Thrust Loss-athon, then crash, repeat.


Could you do the motor test to confirm that the motor order and direction is correct?

When you push the “A” button the front right propeller should spin. “B” should make the back-right propeller spin. “C” should make the back left propeller spin. “D” should make the front-left propeller spin.

Also make sure that the direction matches the image for your frame. This autopilot is configured as a Quad X so the front-right propeller should spin in the counter clockwise direction.

Also make sure that you don’t have any propellers on upside-down.

Please also check that the arrow on the autopilot is pointing towards the front of the vehicle. The servo connections on the Pixhawk should be pointing towards the back of the vehicle.

@dkemxr I made the battery voltage calibration. How can I describe components and take-off weight? I have searched but could not find anything about it.

What motors, props and battery power. And take-off weight (weight including battery).

Sorry, I thought I should describe them to Pixhawk. SunnySky x2814. 1155 propellers. 3.7kg. The trim value of motor3 was 1140 and I made it 1500 then it was fixed. So now it fly in loiter or auto mode. Thank you for your attention @dkemxr

I made al of those things. I do not know was it about that, but the trim value of motor3 was 1140 and I made it 1500 then it was fixed. So now it fly in loiter or auto mode. Thank you for your attention @rmackay9

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