NoYou said you were flying over a frozen lake. How cold was it? Is it possible that the batteries in the controller were too cold?
Yeah. I found that setting later. Next time I’ll do that. Hope there isn’t a next time.Turn off landing protection in vps settings u wont have that thing stopping at 9 ft up saying its unsuitable place to land....i hate that feature. Beside u will always know where you took off from anyway. Plus it makes hand catching way easier and it will not fight u back
TLDR; Running Go4. Lost connection momentarily and RTH initiates. Thereafter the AC would not take ANY commands - from app (command timeouts) or RC. Returned to home but stopped landing at about 9+ ft due to “unsafe landing area.” Had to wait for batt to get to basically zero before it came down low enough to catch. Whew.
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The whole story plus logs...
Flew my P4P out from a lake shore out over the (frozen) lake to a little over 16,000 feet and turned to come back when battery was about 60% (a minute or two before that I got a warning that it was returning to home due to low batt. I was heading out on a headwind. So coming back would be a tailwind and I knew I’d have plenty of batt to get back. I was right).
On the way back it lost connection momentarily. Not sure if I ever lost downlink. Connection came back but it was R’ingTH. I wanted to take control back so I hit the X in Go4 to cancel RTH so I could continue to fly back manually. I got a “Command Timeout.” I kept trying multiple times with command timeout every time. Video and telemetry were fine. I tried to use the sticks to speed up or drop altitude - no response. I tried to cancel RTH with the button on the controller. It stopped beeping for about 5 seconds, then started beeping again. RTH continued. So I let it come back. (I hacked the RTH speed to be faster than stock so I was feeling that would help.)
My concern was what would happen when it came back and did autoland. I wasn’t in an open field. I was on the edge of a lake with benches and a road. And some grass. Could I take control and land it myself?
No.
It got overhead at about 350 ft or whatever alt it was flying at last I had control and started autoland. It was coming down in an OK spot. Not over the bench I launched from but a few feet away over some grass. I still wanted to catch it if I could because some rock sticking out of the ground a foot away. But I had no control.
It got to about 9 ft (eyeball estimate) off the ground and stopped - warning that it was an unsafe area to land. And it wouldn’t land. And I couldn’t force it to. I figured I’d wait for critical battery to force a land and I’d catch it because the ground below wasn’t perfect. edit: obstacle avoidance was off. There may be a setting to disable the safe landing. I’ll have to check and memorize that.
I waited for it to hover from about 25% battery all the way down below 10%. Then 5%. I got warnings saying it was landing due to critical battery.
It wasn’t landing.
It continued to hover. I killed the app and restarted. I restarted the RC. It reconnected fine as far as downlink. But still no control.
Continued to hover. So I figured it would hover till the battery died and shut the motors off. Didn’t think it would completely survive a 9+ ft fall so I waited to catch it in free fall.
Much to my relief it start a slow descent at 1% batt or less. So I gently caught it by the landing gear and it shut off.
The drone had a mind of its own. I’m just glad it was a sane mind. But now I need to figure out what happened.
Any ideas would be appreciated. I’m charging the battery now to see if the problem persists.
Here is the airdata link of the main flight (there is a separate one for the landing but I doubt it’s interesting):
Airdata UAV - Flight Data Analysis for Drones
Here is the phantomhelp upload of the main flight from Go4:
DJI Flight Log Viewer - PhantomHelp.com
I’ll post more info from the power up when that happens.
I think it won't go as he had no response to RC inputs.When all else fails, throw the RC in ATTI mode. 100% of the time this has allowed me to take over the AC when apps wouldn't "let go."
Unfortunately, I'm afraid your instructions from DJI support staff have been what may be considered a default response to questions they have no factual resolve.
If not too much of a bother, could you provide the present f/w versions on both controller and model, as well as the DJI GO version used, out of curiosity.
Maybe, there is some correlation there between you and the OP, particularly if using a recent f/w update, and see how now there are more than one pilot this issue has shown its ugly face to. : )
I tried switching modes. I left that out of my initial post but did mention it in post #7. The AC simply was not taking commands or the RC wasn’t sending them. I also killed and restarted the app so it wouldn’t have held on to the RC.When all else fails, throw the RC in ATTI mode. 100% of the time this has allowed me to take over the AC when apps wouldn't "let go."
How/where can I find out what RC version was tested together with my AC version (the 509 version).I always recommend updating when possible. The issue is to go on the DJI site and determine ALL the latest levels ... firmware/software, drone/controller/DJI Go 4 App ... and keep them in sync. If you decide not to update or to fall back to a previous level, you also need to assure that the levels in ALL devices are at the level they were when tested together and released.
Meanwhile, 16,000 feet VLOS ... amazing ... but incredible.
Thank you for the advice. I am aware of the theoretical risk of running back level code. I am also aware of the very real risk of updating to newer versions due to bugs introduced by DJI - as I have not only read numerous experiences here but have been bitten myself. (Ask the people that lost drones due to the bug introduced in a firmware update that set the home point a couple miles away.) If DJI had better QC I’d be far less hesitant to update.I usually keep all levels up to date. Then it is easy to assure that all levels are in sync and were tested. If you want to fly with back level code, I would advise going to the manufacturer to get documentation on what back levels were tested together. The only thing that I feel is true is that manufacturers don't test ALL combinations of code between drone, RC controller and display device. If you decide not to maintain currency or to take on item's code and back-level it, you are at your own risk. My guess is that many of the "accidents" reported on the site may have been due to inconsistent code levels and that the risk of inconsistent release levels is real.
When all else fails, throw the RC in ATTI mode. 100% of the time this has allowed me to take over the AC when apps wouldn't "let go."
When the aircraft burps, not a thing you can really do. The app is only a conduit and if the RC mode changes between P, Atti or Sport modes aren't having an effect the bird is hung at that point.Switching to ATTI mode didn't work. I switched several times. I had time to quit the DJI app, restart it, etc. Nothing worked.
It wasn’t really hung in the way that I think of software hanging. It was performing all its normal autonomous functions. Just wasn’t taking any inputs.When the aircraft burps, not a thing you can really do. The app is only a conduit and if the RC mode changes between P, Atti or Sport modes aren't having an effect the bird is hung at that point.