Can't Get Y6 to Land on RTL or with Land command in MP

Hi all!
I’ve recently completed my Y6 and have been having a great time with it. It flies amazing. All the PIDs are stock. I took it to the beach several days ago a flew a few missions with RTL after a few waypoints and it came back and landed perfectly. I did this at home as well. I used the RTL = 0 to get it to land as the final waypoint in the mission.

Last night when I got home, I added my GoPro and the OSD devices, so I put a little more weight on the Y6. I flew it with the identical mission by loading the saved waypoints from the previous successful mission.

For some reason, I CAN NOT get the copter to land now. It just hovers above the launch/home point and won’t come down until I switch it back to ‘Stabilize’ mode from ‘Auto’.

I’ve even gone so far as to add an additional ‘Land’ Waypoint right after the RTL command. What am I doing wrong?


It’s likely that it’s getting stuck at 10m. It’s been reported and it’s high on the list to fix for AC3.2…but basically when it’s doing the LAND it first comes down to 10m above home, then it descends to the ground using the LAND_SPEED. What can happen though is it can get stuck at this 10m transition point. We haven’t actually totally figured out why it happens (it shouldn’t happen really). Normally if you leave it long enough it will eventually break through the 10m barrier.
Because we’re not totally sure on the cause I can only guess how to fix it…but maybe increasing the Throttle Accel IMAX value to 10 (default is 5). Increasing the Altitude Hold P to 1.5 (default is 1.0) may also help.
You’ll also probably find that if the copter is below 10m when LAND starts it won’t have this problem…so if you generally fly low you could set the RTL_ALT to 9m or if it’s during a mission put a waypoint above home at 9m before the LAND command.
Sorry, it’s a bug and we will sort it out for AC3.2.

It would be really helpful if you could post your log file so we could analyze it and see if we can understand better what is going on.

Thanks for the suggestions. I’ll try and work on the log file. I think I did one a very long time ago, so I’ll scour the forums for a tutorial and see what I can come up with.

An interesting thing happened though, I removed the extra LiPo battery for the OSD and also the GoPro to see if I could get the copter to land. Sure enough it did. I think this problem is likely due to the Throttle Mid Point being to low or high. In other words, with the additional weight, it has to work harder to stay aloft. I’m going to put the equipment back on and increase the Throttle Mid Point and see if that works.

Does my thought process make sense?

[quote=“rmackay9”]but maybe increasing the Throttle Accel IMAX value to 10 (default is 5). Increasing the Altitude Hold P to 1.5 (default is 1.0) may also help.

Hi !

That works for me, but the Hexa looks a bit nervous while going from loiter to land, will fiddle with the two parameters a bit and report.

Greetings & thx for the workaround.


We just did a bunch of testing with arducopter RTL and land modes with firmware 3.1.2 . We found that if we set the RTL final altitude to 5 meters (rather than 0), letting it come down to loiter at 5 meters, and then commanding the land mode from mission planner, the vehicle would perform auto-land flawlessly every time. Furthermore we quickly realized the advantage of doing this, as it gave us the opportunity to ensure that the area under the vehicle was clear and that it was going to land where we wanted it to before commanding the land function. This does require making “land” one of the modes on your RCTx mode switch, or bring mission planner with you in the field, but I think that it is worth doing it this way anyway.