LITCHI crashed my drone!!!!

[Fly Dawg]

but the point is why a brand new drone designed to bear more than 300mt altidute in an anticyclone zone (zero winds) fails like that!

As I ( We ) have been attempting to relay to you there are numerous reasons that this could occur. There is just not enough data to make that determination. It is pure speculation on the cause. A catastrophic power failure ( Which has happened ), a Bird strike and ejected battery ( Which has happened ), If we had the missing 15 seconds of data, it would be a much more educated method of reasoning, but unfortunately we do not. That said, if you do find the aircraft and it will still power up, you can full the flight data from there and we can give you a better explanation and possibly a direct cause.

 

[solentlife]

It would really not make any difference. Had this been a waypoint mission (Which it wasn't ) the results would have been the same, assuming GPS Signal was lost.


See the first answer.

GPS signal was never lost .... see the log.

Nigel

 

[solentlife]

We quite honestly do not know that you did. The data ends in ATTI mode at Zero Altitude which would be normal if the aircraft were on the ground, in the trees, or upside down. You lost signal for 15 seconds before ATTI mode showed up. It could have also been a compass error or any number of issues.

View attachment 107033

There are NO warnings to indicate Compass error or any other for that matter ... other than loss of Link ... then it soon regains link.

The simple fact is the AC entered ATTI mode and that was it. It was doomed from that point as he did not flip it back to P-GPS ... all he did was wait to see if RTH would happen ... which it will not in those circumstances - he HAD control link ...
The most likely scenario is the AC was hovering in ATTI ... and basically left to its own devices ... it likely hit a tree or ground BEFORE battery reduced enough to initiate smart RTH.

Nigel

 

[Fly Dawg]

If you check his Log ... it shows more than enough SATS locked in ... but because the AC regained control link - it stayed there in ATTI mode.
If he had lost control link ... with the 16 SATS - it would have returned home ... there is no warning of no compass or anything ... its showing fine ...

Correct. The issue is the missing 15 seconds, as we do not know exactly when the aircraft wen't to ATTI. It could have been at any time during the missing data. Nor do we know if GPS was lost during that time and by co-incidence re-aquired while at ground level but before the switchover back to P-GPS....which is GPS lock. You can have several sat's aquired but the switchover from ATTI back to P-GPS was not recorded prior to the end of the log. It takes a at least a second for the switchover. The last half second or so was skipping time.

 

[Fly Dawg]

The simple fact is the AC entered ATTI mode and that was it

This was only in the last .5 seconds of data at zero altitude.

 

[solentlife]

Correct. The issue is the missing 15 seconds, as we do not know exactly when the aircraft wen't to ATTI. It could have been at any time during the missing data. Nor do we know if GPS was lost during that time and by co-incidence re-aquired while at ground level but before the switchover back to P-GPS....which is GPS lock. You can have several sat's aquired but the switchover from ATTI back to P-GPS was not recorded prior to the end of the log. It takes a at least a second for the switchover. The last half second or so was skipping time.

Forget all that about GPS lock ... it is NOT P-GPS ..... you can have GPS acquired and working in ALL modes ! Its a question of whether they are helping YOU fly ...

In ATTI mode if SATS are received and Home Point is recorded ... it will RTH if signal lost.

The SIGNAL LOST is the kicker here ... nothing to do with GPS Lock ..

The 15 secs is the loss of 'Download link' ... you cannot have data if there's no link. Once link re-established - it was shown he was in ATTI mode ... (I have sneeky feeling he flipped the switch !! without realising in the panic).

If he had lost Link now - the AC would have RTH ... but he had Link - so it would not RTH. It makes no difference what mode he is as long as SATS and Home Point are there .....

0.6 or 60 secs makes no odds to be honest ... he was doomed by events.

Nigel

 

[Fly Dawg]

Forget all that about GPS lock ... it is NOT P-GPS ..... you can have GPS acquired and working in ALL modes ! Its a question of whether they are helping YOU fly ...

True, but the FC has to have the calculated solution to transmit the "P-GPS MODE" in relation to the data stream.

The SIGNAL LOST is the kicker here ... nothing to do with GPS Lock ..

Competely agree. It has no bearing.

What I am trying to get to here is the fact that of the missing 15 seconds, which we both agree would give a better idea of what occurred. My point is more related to the fact that it appears that this was some sort of a power failure for whatever reason. If the aircraft were in RTH, with or without GPS ( And I still do not see how that is possible ) those last data points indicate that the aircraft is either on the ground or in the trees. Altitude went from almost 1000ft to zero at some point during the missing 15 seconds. It looks to me from that information that RTH never happened.

 

[Berzuo]

If this can help you, and I really really appreciate how much interest and competence you are putting in the matter, before the mess Litchi showed an error, it was red on the right/upper side of the screen, something about "drone movement detected....if problem persist call DJI" something like that

 

[Fly Dawg]

@solentlife I think I just determined what our RTH discrepancy is: If you manually switch to ATTI and RTH is required it will do so. Alternatively, if the aircraft auto-switches to ATTI, RTH will not work. That makes more sense.

 

[Fly Dawg]

"drone movement detected....if problem persist call DJI" something like that

That's a new one. Never heard of a message like that before. Are you sure that's what it said?

 

[Berzuo]

Yes I stared few seconds in order to understand why the drone disconnected and no RTH was prompting, i was using LITCHI in his last iOS version

 

[Fly Dawg]

Yes I stared few seconds in order to understand why the drone disconnected and no RTH was prompting

If you are disconnected, you will not get a prompt because the RC can't receive it from the aircraft.

 

[Berzuo]

it was at the same moment, i clearly seen the gimbal going awry and poiting flat(i could see the blades going) from the 45°, i had the impression something was going on and then it disconnected

 

[Fly Dawg]

it was at the same moment, i clearly seen the gimbal going awry and poiting flat(i could see the blades going) from the 45°, i had the impression something was going on and then it disconnected

If that is true, that would "inititially" confirm some sort of catastrophic failure, of unknown origins, as was previously mentioned. Without additional data, this is about as far as we can go with these "speculations". Not much more that can be added, unfortunately.

 

[Berzuo]

If that is true, that would "inititially" confirm some sort of catastrophic failure, of unknown origins, as was previously mentioned. Without additional data, this is about as far as we can go with these "speculations". Not much more that can be added, unfortunately.

indeed is that, i really hope to find the remnants of the drone and retrieve the missing data, in any case thank you very much for the insights provided in this matter

 

[Douggieboy]

indeed is that, i really hope to find the remnants of the drone and retrieve the missing data, in any case thank you very much for the insights provided in this matter

Once you realize that you’re in trouble, whether that is caused by out of range or pilot error, to engage the return to home function, you must immediately flip the flight mode control switch back to P. This will enable the gps and execute return to home as soon as you press and hold the button on your transmitter

If you lose signal in any mode, the drone should stop and hover in place if return to home has not been set as the default action. It should not lose altitude unless land immediately has been selected in the event of signal loss

 

[epx]

I was around 1km at cruising speed quite high, but didn’t anything very reckless, I was using litchi on iOS after switching to FCC with an android phone (which was shut and disconnected as well as rc/ac rebooted) the prior day I did a similar flight not more than 1km with the Android phone and dji 3.1.18 and all was fine, rth on dc etc. I don’t think this was a very reckless flight, perfect weather, full battery , drone almost new,no wind... I’m appalled!

”Quite high” is too high. Flying out of sight is dangerous for people and things under it. Like kids, pets, cars — you can’t afford that.
Do not blame the drone, the software or anything else. Blame the pilot who think this is some kind of autonomous robot. It is not.
You should see the drone from your ground position, not just the video because, as we learn all the time, video transmission is very very unreliable.
So do not set distance or height records.
I suppose you had put your name and phone number on your drone? Then maybe someone finds it. Good luck!

 

[timholyoake]

There is a reason why there is P mode. It makes it easier and safer. There is a reason why the flight rules state 400 met high 500 m distance as a MAX and always in VLOS.
That reason is so you can control your drone and keep it.
Also flying over populated areas increase the likely hood of interference and is also illegal .
You lost your drone because you were reckless. Sorry , plain and simple.

 

[sar104]

it was at the same moment, i clearly seen the gimbal going awry and poiting flat(i could see the blades going) from the 45°, i had the impression something was going on and then it disconnected

There was gimbal movement at the end because you were applying gimbal control input after the downlink re-established. There's no indication of a problem there.

 

[Antwarrior]

I believe I had also had a crash because of Litchi. I experienced a problem on a P4Pro with the gimbal vibrating when in POI mode using Litchi to control the height for the camera to point at. I tried to repeat the issue under more controlled conditions in the fields near my house. I managed to do a perfect orbit of an old barn with the gimbal pointing ate same height as I ascended and descended, I then tried on another old barn and this time experienced severe vibration. I attempted to fly home manually but the drone would not respond, I tried pushing return to home, no joy: quit out of litchi and relaunch, no: quit out of litchi and launch DJI Go, no: switched controller off and drone fell out of sky.
Black Box flight record proved inconclusive, even to the guys at Drone Doctor, Litchi swear blind that Litchi will not cause a crash, but I haven't felt confident enough to use it since. Anyone else experienced anything similar

Paul