That is the same for me, except the drone was only 6meters horizontal and perhaps 8meters directly from me! Drone just went into RTH (I believe due to loss of signal).
Fausto
P4P Complete Loss of control, til crash
- Thread starter Fausto
- Start date
Fausto
Apologies for being a bit late to the discussion. This was an unusual case, in that what happened appears to be a loss of uplink data to the FC at around 720 seconds. As a result, at 725 seconds, the FC initiated RTH (OutOfControlGoHome) which immediately converted to autolanding because the aircraft was too close to the home point. The landing point was unsuitable and so the FC switched to "hover". The downlink was mostly continuous, with just a few gaps, but there was no further uplink to the FC, hence the "command timeout" messages from the RC, and the aircraft eventually went to forced landing due to low battery.
I've not seen such a case of uplink loss - especially where the downlink was good.
I've not seen such a case of uplink loss - especially where the downlink was good.
I saw it once just like this, as documented in the thread I linked to above. Don’t recall if you were on that thread at the time. It definitely seems like a pathological case. I would lean toward the A/C going deaf rather than the RC not sending. Because restart of the RC (and GO4) didn’t help.
RodPad
Premium Pilot
I had that thread on "watch" but I didn't analyze the incident. It does sound similar, with the "command timeout".
Thank you sar104 for taking the time to look at these files. It makes me feel better that it appears that basically there was nothing I could have done differently.
One point though, it was not a complete loss of uplink as I could still control the gimbal (i.e. tilt).
ALSO, (something I have not mentioned previously) I noticed that when I applied rudder inputs while there was no flight reaction / change the gimbal did move slightly in the same direction. I assume this is part of the mixing process to absorb the movement of the camera? Mind you this happens while the drone is sitting on the ground without the motors even started... To me this means the ac was receiving stick inputs, of sorts.
Cheers,
Fausto
That's why I referred specifically to the FC uplink. The gimbal was responding, at least at some times:
RodPad
Premium Pilot
This is where I was on Post #17
"What Is interesting that you had live video from the Phantom and the data from the camera (ISO, SD card capacity, etc) and remote control controlling the camera (Still had a two way link).
But no aircraft data, which I assume should have been in the same signal as the camera data.
Does anybody know if the two data streams should be in the same signal?
@quaddamage,
I think your the P3A/P guy, on camera and communication from the gimbal. Could this happen on a P3, would you know about the P4?"
Why I asked @quaddamage, if he had any info on the communications of a P4.
Have a look at the communications on a P3S.
P3S block diagram.
Post #17 Second part
"The disconnect message you have a video of, what does it show in your flight log?
I assume you can play your flight back in GO, have you done that?"
I was wondering if you were to playback your flight in DJI-Go.
Does the "Aircraft Disconnected warning" show up again.
Both times when you were downloading the .dat files and when your flying, well trying to fly.
And what now,
What would you do if this happens again, anybody got some ideas?
Rod
Hi Rod,
I think I need to apologise as I may have incorrectly identified the recording as being the same issue. The recording was taken while the drone was on my desk connected to my laptop to download the DAT files, not being flown. It was taking a long time so I left the room for a while. When I returned I noticed the disconnection warning and that I still had gimbal control, that's when I recorded. Following that recording when I subsequently tried to retrieve the DAT file as requested, I noticed that when I went into the upload mode in DJI Assistant, the drone once again disconnected from the app / RC. As soon as I quite Assistance and removed the USB connection the RC / AC connection was restored.
Sorry for the confusion...
BTW, when I was trying to download the DAT files from the drone for the actual incident I discovered there were no files for that day on the AC, flights before and after (when the drone was started) were there though.
I think I need to apologise as I may have incorrectly identified the recording as being the same issue. The recording was taken while the drone was on my desk connected to my laptop to download the DAT files, not being flown. It was taking a long time so I left the room for a while. When I returned I noticed the disconnection warning and that I still had gimbal control, that's when I recorded. Following that recording when I subsequently tried to retrieve the DAT file as requested, I noticed that when I went into the upload mode in DJI Assistant, the drone once again disconnected from the app / RC. As soon as I quite Assistance and removed the USB connection the RC / AC connection was restored.
Sorry for the confusion...
BTW, when I was trying to download the DAT files from the drone for the actual incident I discovered there were no files for that day on the AC, flights before and after (when the drone was started) were there though.
RodPad
Premium Pilot
All good,
I started a simply reply then I added some stuff, then some more, I think still important, but not tonight.
Rod
RodPad
Premium Pilot
You should be able to play back any of your flights in DJI-Go.
I think anytime Phantom and DJI-Go is active, a flight log is being saved, whether you start the motors or not.
Rod
I think anytime Phantom and DJI-Go is active, a flight log is being saved, whether you start the motors or not.
Rod
Only the aircraft .dat. The device files begin at motor start.
RodPad
Premium Pilot
Thanks,
Wasn't sure about P4's and haven't flown with GO for a couple of years.
But if he played back the problem flight, I was wondering if this "Aircraft Disconnected" would show up in the playback?
Also, was this "Aircraft Disconnected" that happen as he was downloading the Phantoms .dat file. Was actually related to a timeout transferring the file(s)? Since the files are so large.
Anyways, I will give this thread a rest.
Rod
Also the mobile device DAT - that begins as soon as the app connects following aircraft power up.
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