P3 inverted and fell from the sky...into a lake :-(

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After approx 35 successful flights with my P3 advanced, today it inverted mid-flight and fell from the sky. I was flying over water and the P3 fell into the water and was never recovered :-( .

There was a bit of a breeze on the day of the flight, not too strong and I was flying into the wind (backwards, see video) when the crash happened. I was high than all obstacles (accept maybe birds?!).

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Any idea what could have happened? I double check all props were tight before take off. However, for the past few flights I've been getting "Motor Idling (Loose or Missing Propeller)" errors but each time I landed and checked they were super tight. Maybe this was a sign of early motor failure? Looking at the flight log it seemed to automatically switch to ATTI mode after "speed error" then there was an MFI error then a "Compass Error" then crash. All happened in 0.2s!

https://www.phantomhelp.com/LogViewer/...

Airdata UAV - Flight Data Analysis for Drones

What can I learn from this? Thanks.
 
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I would have been greatly concerned with those warnings and would not have flown over water until I got to the bottom of it (I'm not talking about the lake here).
 
Like Big said, you should had not flight with all these warnings signals until you found out how to fix this. In my case, I have experienced the strong interference warning but I moved to another area and it fixed the issue. Phantoms drone are not cheap at all, this is an investment that needs to be taking care very well.
 
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Like Big said, you should had not flight with all these warnings signals until you found out how to fix this. In my case, I have experienced the strong interference warning but I moved to another area and it fixed the issue. Phantoms drone are not cheap at all, this is an investment that needs to be taking care very well.
I do not think he needs a lecture, he is asking for help.:rolleyes:
 
Not an engineer but seems like a bunch of error messages(well, a couple that lasted for a few seconds)won't result in a lost prop. And a prop still in one piece would have made a second splash...did you see one? I think that you might have gotten a dose of some of the increased solar activity reported lately. I know that local avionics people are seeing what they call a noticeable uptick in avionics related failures this month. Reading your log reminded me of reading a flight data recorder transcript for a plane with a fire in the avionics bay. As your speed error and prop warnings are from one sensor bank and the compass/magnetic field warnings from another, unrelated sensor set it looks kind of like your bird had a stroke.
 
"I was flying over water and the P3 fell into the water and was never recovered :- ." but still has all video !!!!!!!!!!
 
crash.MOV
<If it will not play click the download arrow instead>

Here is the video of my drone doing the same thing. Flipping upside down and flying full blast from 200 feet into the ground. I had to replace so many things to get it flying again and now I don't have any trust in it. Yesterday I was helping a friend with his P2 vision. It takes off really lop sided but once use to it I had no problem. It would take off, fly for 30 seconds, then flashing red lights and it lands. My friend tries to get his drone to take of and it flips over and starts making a horrible noise.

Now my point.
The noise was one of the motors. I picked up the drone and all but one prop instantly starts spinning. One motor making a loud noise until I spun it's propeller and it starts working. The motors obviously have some sort of clutch to protect them when there are mistakes made by the operator.

My drone never crashed, nothing but perfect flying in all kinds of cool places. When it crashed all I did was maybe take off too hard. Being in a hurry to fly. I feel that one motor on my drone had its safety clutch engage or something. DJI blamed prop failure and I believed them until yesterday. I do not trust my drone now because of what I have had to do to get it in the air again. If I were to buy another drone I would again buy a P3A because of the hours of successful flights and video I've gotten from my drone. My advice to you is to replace motors after 50+ hours of flight. Motors are cheap. Sorry you were unable to recover your drone.
 
Speculation based on my engineering knowledge:

Looks like a short but very strong EM interference. Could be caused by external sources (cosmic radiation?) but that would probably restart GPS (since it's on top). Since GPS didn't restarted with 0 satellites, I'd say the source was internal (short peak in current). Drawing of such a large current could be only caused by high power components - ESCs or motors.
 
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Speculation based on my engineering knowledge:

Looks like a short but very strong EM interference. Could be caused by external sources (cosmic radiation?) but that would probably restart GPS (since it's on top). Since GPS didn't restarted with 0 satellites, I'd say the source was internal (short peak in current). Drawing of such a large current could be only caused by high power components - ESCs or motors.

I think we should be comfortable making a more informed guess here, particularly with the benefit of the log files. If you look at the log you will see that loose rotor is indicated as an issue at commencement if flight and the last reported errors are very telling, motor overspeed is typical of a prop being lost in flight. The following compass errors would almost certainly be as a result of the out of spec yaw rate attributed to the lost prop.

IMG_2869.PNG
 
Speculation based on my engineering knowledge:

Looks like a short but very strong EM interference. Could be caused by external sources (cosmic radiation?) but that would probably restart GPS (since it's on top). Since GPS didn't restarted with 0 satellites, I'd say the source was internal (short peak in current). Drawing of such a large current could be only caused by high power components - ESCs or motors.
Good day, that hypothesis is a super stretch. [emoji44]
 
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If you look at the log you will see that loose rotor is indicated as an issue at commencement if flight and the last reported errors are very telling, motor overspeed is typical of a prop being lost in flight. The following compass errors would almost certainly be as a result of the out of spec yaw rate attributed to the lost prop.

Note that Glyn suggested this is probably not the case. But I agree it is possible. The short video glitch before falling could be attributed to sudden change in motor load. But I consider HW failure to be more probable.
 
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Note that Glyn suggested this is probably not the case. But I agree it is possible. The short video glitch before falling could be attributed to sudden change in motor load. But I consider HW failure to be more probable.
I'd put prop loss in hardware failure, motor overspeed is more indicative of this than a motor failure (rate) or ESC (which would be reported as ESC error). We can be confident it wasn't cosmic rays.
 
Not an engineer but seems like a bunch of error messages(well, a couple that lasted for a few seconds)won't result in a lost prop. And a prop still in one piece would have made a second splash...did you see one? I think that you might have gotten a dose of some of the increased solar activity reported lately. I know that local avionics people are seeing what they call a noticeable uptick in avionics related failures this month. Reading your log reminded me of reading a flight data recorder transcript for a plane with a fire in the avionics bay. As your speed error and prop warnings are from one sensor bank and the compass/magnetic field warnings from another, unrelated sensor set it looks kind of like your bird had a stroke.

Can you link to these reports of recent solar related avionics failures or anomalies? I couldn't find any.

What sensor bank are you referring to?
Until then I call such speculation BS.
 
Thanks guys, lots in interesting insight.

Yup, the video was from the DJI app. Sadly, I'm not making it up! I would much prefer my drone back rather than some low res video and a marginally interesting logfile..

On the day of the incident the wind was about 15mph and I was flying backwards into the wind at pretty much full speed. As mentioned maybe the extra load on the motors caused a prop failure or current spike which affected the GPS. The crash into the lake was wayy to far for me to able to too is there was one or two splashes due to a propellor failure.

Hopefully I will be able to draw some conclusions next weekend; I've gathered together a team of friends with dones and scuba gear, we're gonna try and retrieve the drone based on the last reported location. The lake should only be 5-10m at the depth. I wonder if any of the electronics will be salvageable? I very much doubt it, however it's a freshwater lake therefore the SD card should be ok and maybe some props!

I'm quite new to drone flying; out of interest is this sort of incident common with P3's? How many of you have randomly lost a drone? Should a risk buying another P3? Or maybe a p4 / mavic are more reliable? My confidence to invest more money in drones has been dented somewhat...however they are so much fun! I very much enjoyed my 7 days of flying! Here's some more successful video I made a couple of days before:

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Your right, watching the video again the slight jerk in the video just before inverting does look to indicate a prop failure. Could flying fast on a windy day cause a prop to loosen? I'm certain I checked the props were tight before launch. I had been successfully flying for over 6 min at the time of the incident.
 
Well I guess if your mates can locate and retrieve your drone, all will be revealed. The video and WTBs idea makes a lot of sense giving the multiple warnings in the log file. I've read of similar failures on threaded props which may explain why the P4 prop locking mechanism was updated. You may had a cracked hub on one or more of your props and you hadn't noticed it when tightening them. I flew my P3S and now P4 in relatively high winds with never an issue so I doubt it would be a design fault from DJI.
 
After approx 35 successful flights with my P3 advanced, today it inverted mid-flight and fell from the sky. I was flying over water and the P3 fell into the water and was never recovered :-( .

There was a bit of a breeze on the day of the flight, not too strong and I was flying into the wind (backwards, see video) when the crash happened. I was high than all obstacles (accept maybe birds?!).

To view this content we will need your consent to set third party cookies.
For more detailed information, see our cookies page.

Any idea what could have happened? I double check all props were tight before take off. However, for the past few flights I've been getting "Motor Idling (Loose or Missing Propeller)" errors but each time I landed and checked they were super tight. Maybe this was a sign of early motor failure? Looking at the flight log it seemed to automatically switch to ATTI mode after "speed error" then there was an MFI error then a "Compass Error" then crash. All happened in 0.2s!

https://www.phantomhelp.com/LogViewer/...

Airdata UAV - Flight Data Analysis for Drones

What can I learn from this? Thanks.
I too just started getting that same error message [Loose or Missing Propeller] and no, it had nothing to do with the props. I landed with no issue but saw that error message when preparing for take off. Matter of fact, I get a lot of errors and every time they go away. Frankly, I believe the software is the culprit 90% of the time.
 
You have a good chance of repairing the AC if it is in fresh water. The PCB's are all coated. A full disassembly and wash everything in IPA and you might be suprised- salt water and I'd say don't even bother trying to find it.

Where you using the standard DJI props? It is rare for them to spin off but not unheard of. If you search threads here you will find that the overspeed error and what was depicted in your video do correlate with others experience (where the bird was recovered missing a prop and/or the operator was close enough to see it fly off in flight).
 

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