Pixhawk Y6B 3.5.3 flip at tafeoff

Hello all,

Two years ago, i built an Y6. It fly good and have a heavy presence in the sky with its 1 meter.

My first GPS was a droteck with high precision but it takes him a long time to get it. I decide to switch it with an SE100. I don’t plug it’s external compass because the SE100 was turn by 180° thanks to the cable and the internal compass to the job.

This drone don’t flight often, three or four times in the year, the initial project was aborted and I’m flighting with planes and smaller quads.

So last week I decide to do an annual upgrade and the autotun to have better PID.
But at take off it roll on right and finish on it’s back. I test an second take off in stabilized mode but it to the same…

I have check the motors plugs and their rotations with the Y6B schema. I used mission planner motor test and have this sequance :
• motor A pluged 5
• motor B pluged 1
• motor C pluged 6
• motor D pluged 4
• motor E pluged 2
• motor F pluged 3

I haven’t found the mapping between motor’s letter and the pixhawk output for an Y6. Can you validate the previous results ?

Other information on the motor test : When I request all motors with the “Test all motors” button. B and C motors don’t turn and change the “throttle %” change nothing. B and C are working individually. When I request “Test all in Sequence”, the motor A spin during the duration and that’s all, B C D … stay fix.

Other informations on what I have done between a working flight and my last crashing take off :

• I changed my RC remote. My Frsky horus is in reparation so i pluged my last hitec Aurora. This is the same compatible receiver. I have done the calibration.
• Plug-in and remove the external compass of the SE100. I don’t find the appropriate rotation. I have done the compass and accelerometer calibration when I remove the compass.
• I update the firmware version to the 3.5.3. I don’t remember the latest version. I made the last update six or eight months ago.

How to add the logs in this topic?

Thanks for your help :slight_smile:

throw the letters out
Use the numbers and don’t worry if the test slots don’t match
just make sure the position and direction of props are correct.
Using this reference, I have my rail numbers matched to these numbers on the motor position, and then make sure the direction of the props are correct