Mini 2 simply vanished in thin air, now what?

[singram]

Hello all! Long story short, than I'll get to the questions.

Yesterday afternoon, my Mini 2 seems to have catastrophically failed in mid air over water. I went thru the typical start up process, waited for the GPS locks, got the Take off Permitted prompt, then took off about 65ft above the river in my backyard deck planning on getting some pics/vids of boats and jet skis. This is something I've done daily since buying it 2 yrs ago. Nothing unusual. About 20ft away, I got a weak GPS warning. By the time I turned it around to come home, I got the "homepoint updated, check it on the map" prompt, so I assumed whatever glitched, settled itself and proceeded with my flight. 3-4 minutes into the flight down the river, I again got the weak GPS signal. I proceeded to manually fly it back home, but a second later, I got the dreaded "aircraft disconnected" error, and I never seen the drone again.

I attempted the find my drone option just for the heck of it, even though I'm 100% sure its in/under the water by now. Surprisingly, the app located it as being in a neighborhood yard maybe a mile away. I drove to the location, and no drone. Gone. I took a look at the video at the time of the failure, and there was no tumbling out of the sky like you'd expect if you hit something(bird, whatever). It was filming, then black out.

Soooo, now what? I didnt buy the Refresh plan for the Mini 2 (only my new Mavic 3), but I assume either way without the drone, I'm SOL? I understand the Flight Records are stored on my iphone. Do they include error logs that I could use to open a case with DJI. If this was due to user error, I'd be fine with eating it, learn from it and moving on. Having no closure though really bothers me, and frankly, I am now deathly afraid to put the Mavic in the air.

Any thought appreciated!

 

[waynorth]

The only way somebody can help you is to see your flight log.
Here is how to find it on your phone and upload it to Phantomhelp:

DJI Flight Log Viewer | Phantom Help

Upload and view flight logs from your DJI drones

www.phantomhelp.com

 

[Droning on and on...]

The GPS issues are a concern. If you had an outright GPS hardware failure, it would not be able to return home automatically.

Also, did you check the map when it locked a home point while in flight? That would be my first place to look, not wherever it was when it disconnected (find my drone feature).

 

[singram]

The only way somebody can help you is to see your flight log.
Here is how to find it on your phone and upload it to Phantomhelp:

DJI Flight Log Viewer | Phantom Help

Upload and view flight logs from your DJI drones

www.phantomhelp.com

Wow, that was quick! Thanks, I'll work on that and report back my findings!

 

[singram]

The GPS issues are a concern. If you had an outright GPS hardware failure, it would not be able to return home automatically.

Also, did you check the map when it locked a home point while in flight? That would be my first place to look, not wherever it was when it disconnected (find my drone feature).

Apologies for the confusion. I didnt attempt an Auto Return Home. I typically only fly and return home manually.

I did not check where the drone locked the home point since I never rely on the Return Home feature. I only brought up the "homepoint updated.." prompt in my story as I use this prompt to assure me I'm good from a GPS standpoint.

 

[waynorth]

Wow, that was quick! Thanks, I'll work on that and report back my findings!

Just remember to share your log for others to see. There are some persons here that can do a very thorough analysis of the flight log and it is amazing what they can find.

 

[Cafguy]

knowing the story beforehand I think the weak GPS warning should have been your stopping point but I can't say I wouldn't have done the same as you thinking the weak signal would surely improve. As to What to do after you find out what actually happened Well Mini 2s are reasonably priced on eBay right now so I guess you could get a Drone only deal.

 

[Yorkshire_Pud]

If the drone still had a GPS 'error' when it disconnected then I am sorry to say I think it will have descended WHERE IT WAS.

If the drone got GPS back then the drone will possibly have started an RTH when it disconnected.

I am not sure what would happen if GPS was re-established whilst it was in the previously mentioned descent and there is another corollary, what was the setting of the failsafe option, normally that would be RTH ( it is recorded in the log you have been asked for ) and if that was the case then it might have started an RTH.
HOWEVER it is likely that the homepoint it might have returned to was wherever "About 20ft away," was.

 

[Droning on and on...]

Apologies for the confusion. I didnt attempt an Auto Return Home. I typically only fly and return home manually.

I did not check where the drone locked the home point since I never rely on the Return Home feature. I only brought up the "homepoint updated.." prompt in my story as I use this prompt to assure me I'm good from a GPS standpoint.

I wasn't clear.

When you lost connection, the Failsafe RTH (I think that's what they call the lost connection RTH), would have kicked in, and the drone would have executed the mode you had set in Fly – return to home, hover, or land.

Assuming you had it set to RTH, the default, it would have returned to that HP that it told you it set while you were in flight. That's where you should look for it.

That HP is in the logs, so you can still determine it and go look there.

 

[singram]

Understood. I'll have a look there as well. For what its worth, I've attached a copy of the flight logs.

 

[Yorkshire_Pud]

Could you post the URL for the phantomhelp page please?
The failsafe option was set to go home, column DL or 116.

 

[singram]

knowing the story beforehand I think the weak GPS warning should have been your stopping point but I can't say I wouldn't have done the same as you thinking the weak signal would surely improve. As to What to do after you find out what actually happened Well Mini 2s are reasonably priced on eBay right now so I guess you could get a Drone only deal.

Yeah, will probably go the Ebay route for a replacement.

 

[singram]

Could you post the URL for the phantomhelp page please?
The failsafe option was set to go home, column DL or 116.

DJI Flight Log Viewer | Phantom Help

Upload and view flight logs from your DJI drones

www.phantomhelp.com

 

[Yorkshire_Pud]

DJI Flight Log Viewer | Phantom Help

Upload and view flight logs from your DJI drones

www.phantomhelp.com

How accurate do you think the early flight track is, up to the moment in time where the home point was set?

 

[singram]

How accurate do you think the early flight track is, up to the moment in time where the home point was set?

I'd say very accurate, unfortunately

 

[Yorkshire_Pud]

So were you stood under that clump of trees adjacent to that promontory?
Did you check in and under the trees where it went missing? What height are those trees?
It's not often I will say this but additional height might have been a better option before trying to fly it home, it might have also given you a better signal but if you remained in the wooded area that is questionable.
Hindsight is a wonderful thing.
How soon after disconnection did you go looking for it? Whilst you remained around the launch site where in the sky were you looking for the drone?
If the drone RTH'ed it would have waited for around 11 sec before starting the failsafe behaviour, then flown backwards for 50m (say 5 or 6sec), climbed 80ft (8sec ?) then flown to the homepoint 50sec, with the home point being out over the river.

 

[slup]

This wasn't anything else than a plain pilot error I'm afraid.

You launched without a recorded HP... it was then later recorded 33.45sec into the flight when the GPS level reached 4 out of max 5 (out over the river). You then flew (without any GPS problems) 1779ft away on a 55,7ft height... & when the RC connection was lost at 183,47sec into the flight you mainly had a whole forest in between the RC and drone.

This was just an exercise in flying out of line of sight until the connection was lost ... what complicated thing's was the late recorded HP over the river & what it seems, the crash in the tree tops just in the end. (Lat 41.9616 Lon -88.3166).

Here the relevant data regarding # of locked satellites, GPS level, heights & distances, up/down link & when the HP was recorded.



Here the uncommanded attitude changes just before the RC connection is lost which indicate a crash... (dashed is stick commands, the rest pitch, roll & yaw)



And here a view to depict the out of line of sight... showing the sudden height change just before the red cross.

 

[singram]

This wasn't anything else than a plain pilot error I'm afraid.

You launched without a recorded HP... it was then later recorded 33.45sec into the flight when the GPS level reached 4 out of max 5 (out over the river). You then flew (without any GPS problems) 1779ft away on a 55,7ft height... & when the RC connection was lost at 183,47sec into the flight you mainly had a whole forest in between the RC and drone.

This was just an exercise in flying out of line of sight until the connection was lost ... what complicated thing's was the late recorded HP over the river & what it seems, the crash in the tree tops just in the end. (Lat 41.9616 Lon -88.3166).

Here the relevant data regarding # of locked satellites, GPS level, heights & distances, up/down link & when the HP was recorded.

View attachment 163836

Here the uncommanded attitude changes just before the RC connection is lost which indicate a crash... (dashed is stick commands, the rest pitch, roll & yaw)

View attachment 163837

And here a view to depict the out of line of sight... showing the sudden height change just before the red cross.

View attachment 163838

Wow, thanks for taking the time to compile and explain all that, Slup. I suppose I'm inclined to agree with you. I'm still very much unclear as to why I was good to go on initial take off till I got over the water. But yeah, bringing it back home and landing to require sats hence building a proper RTH location could have avoided all this for sure. Thanks all!

 

[rwilliam99]

Wow, thanks for taking the time to compile and explain all that, Slup. I suppose I'm inclined to agree with you. I'm still very much unclear as to why I was good to go on initial take off till I got over the water. But yeah, bringing it back home and landing to require sats hence building a proper RTH location could have avoided all this for sure. Thanks all!

If I've learned one thing from reading this forum, it is that you need to pay attention to ALL the warnings and messages coming from the controller/drone. GPS warnings are nothing to disregard.

I've learned a lot of stuff the hard way unfortunately. Sorry about your drone....

 

[slup]

... I'm still very much unclear as to why I was good to go on initial take off...

Waiting until you hear that lady voice announce that the HP has been recorded is somewhat voluntary (but highly recommended)... you can take off indoors without a GPS lock for instance. It's all up to you as a pilot to know how to handle your craft & what risks you're willing to take in different circumstances & what the consequences can be if you lose the RC connection like in your flight.

But your flight ended in a crash... so that the HP was recorded in the wrong place didn't matter, either you were confused right there close to the tree tops or you were flying half blind with a really sketchy video link... or you didn't pay attention.