207 good flights and literally fell 400 ft. from the sky.

On a completely unrelated topic...light bulbs exhibit electrical characteristics that would allow predicting failure as well, if one chose to monitor those characteristics he could very easily predict their failure, as well as the controllers that operate the lights
 
I have copied the last flight log files from the app to my desk top. These are the last two entries. Is there anyone that can decipher this or point me in a direction to someone who can? After reading up on others experiences I'm not looking to hear from DJI any time soon.

A little more info now that I've had time to reflect:
• Heading out about 2 minutes in to the flight at 380 feet I remember a strange but slow yaw to the right as I would accelerate forward from a still hover. This was more subtle but similar to the same jerking yaw that then starting spinning on the way back. I thought it maybe wind resistance. I stopped and hovered then checked my IMU mod and battery cell voltages to be safe. I only took a quick look but all appeared ok.
• When I switched to ATTI mode, after the first couple of random yawing 360's, it flew "fairly" straight...then started spinning again. I switched back to GPS at this point but it was on it's way down. Many onscreen alerts at this point about compass, GPS, Atti etc.
• I almost forgot that I was filming when it crashed. Luckily I removed the SD card before packing it up to ship. Checked the footage to analyze the preceding events and downward spiral. To my surprise the camera stopped recording by itself at about 3 minutes into the 7 minute flight. So the bird went down 3 minutes after the camera stopped. This may be nothing but thought I'd mention it.

Thank you.
 

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The text files can be imported to a spreadsheet. The KML file is for google earth

Sent from my SM-G920P using Tapatalk
 
I had a loss the other day. Lost RC signal and didn't have my eye on the bird but on the screen.....never saw again!
No RTH, did the usual pre flight checks but did not check the fail safe, so not sure. I thought it was on RTH on loss of signal....no cache...
Anyhow immediate and final....
Luckily (well sorta) I was over the ocean.....
Me speculating it was battery...but who knows?
So I am moving on to an Inspire but gotta sell my RC and stuff....just added the HDMI board as well....
Ok move on.....
My Inspire1 fell out of the sky in a very similar looking event. Was only 26m high and it just dropped like a stone, into a lake... None of these machines are immune to an elctro-brainfart. Only difference is that if the I1 does it you're outta some serious cash. Makes losing a P3 feel like losing a toy. Enjoy the Inspire! It's a beast compared to the P3 :D
 
I'm very sorry for your loss. I am the developer of healthydrones.com and I just looked at the log. It looks like something happened at 6 minutes 4.4 seconds. There is a severe roll to the left (not a turn – but a roll) and severe pitch forward – in a response to that the aircraft turns to the right to balance. I don't think any compass issue would cause that and GPS looks good at that time. The aircraft still maintains altitude (although it does lose gradually about 2 feet in 4 seconds or so) until you start descending at 6m 15seconds.

When this starts (6:04.4), the airplane doesn’t bump up or down, and the speed remains almost the same – so this looks less like a crash into an object, and more like a problem with motor/propeller, possibly the front-left which could cause such a response, but this is just my preliminary review. Here's more:
  • At 6:07 the same exact thing happens again: strong roll to the left, strong pitch forward, aircraft corrects to the right.
  • At 6:16, about 0.6 seconds after you push the throttle down (and keep it down), the aircraft miraculously balances itself, but it resumes the crazy left roll and forward pitch as soon as you release the throttle at around 6:18.
  • The same ‘healing’ response happens again at 6:20 (again when you push the throttle down for a couple of seconds), and again at 6:25 or so, which continues until 6:31
  • Around 6:31 you slowly bring the throttle back to the center and that’s pretty much sends the aircraft into its death spin.
All this stuff indicate more of a motor/propeller failure and not a GPS/Compass issues. When you descend, the aircraft needs less lift and therefore a partial motor/propeller failure could be more easily compensated by the other properly working motors.

I am also curious - what was the weather like when you were flying? were there any serious winds? Not that I am suggesting that this happened because of winds (it didn't), but it will help me analyze the log better if I know the environment.

I will spend more time on this over the weekend (I'm on a business trip now). A lot of this kind of analysis is on my to do list for future reports and hopefully they will help someone one day.

I hope this is helpful. Again sorry for your loss and I hope you get a new phantom from DJI quickly.
 
I'm very sorry for your loss. I am the developer of healthydrones.com and I just looked at the log. It looks like something happened at 6 minutes 4.4 seconds. There is a severe roll to the left (not a turn – but a roll) and severe pitch forward – in a response to that the aircraft turns to the right to balance. I don't think any compass issue would cause that and GPS looks good at that time. The aircraft still maintains altitude (although it does lose gradually about 2 feet in 4 seconds or so) until you start descending at 6m 15seconds.

When this starts (6:04.4), the airplane doesn’t bump up or down, and the speed remains almost the same – so this looks less like a crash into an object, and more like a problem with motor/propeller, possibly the front-left which could cause such a response, but this is just my preliminary review. Here's more:
  • At 6:07 the same exact thing happens again: strong roll to the left, strong pitch forward, aircraft corrects to the right.
  • At 6:16, about 0.6 seconds after you push the throttle down (and keep it down), the aircraft miraculously balances itself, but it resumes the crazy left roll and forward pitch as soon as you release the throttle at around 6:18.
  • The same ‘healing’ response happens again at 6:20 (again when you push the throttle down for a couple of seconds), and again at 6:25 or so, which continues until 6:31
  • Around 6:31 you slowly bring the throttle back to the center and that’s pretty much sends the aircraft into its death spin.
All this stuff indicate more of a motor/propeller failure and not a GPS/Compass issues. When you descend, the aircraft needs less lift and therefore a partial motor/propeller failure could be more easily compensated by the other properly working motors.

I am also curious - what was the weather like when you were flying? were there any serious winds? Not that I am suggesting that this happened because of winds (it didn't), but it will help me analyze the log better if I know the environment.

I will spend more time on this over the weekend (I'm on a business trip now). A lot of this kind of analysis is on my to do list for future reports and hopefully they will help someone one day.

I hope this is helpful. Again sorry for your loss and I hope you get a new phantom from DJI quickly.

Thank you so very much for taking the time to look at this. I've also signed up to healthydrones.com and viewed my data. What a great resource!
The weather was beautiful. Almost too perfect. Pure sun with no clouds. 80º and supposedly a 5mph wind. But even at 2pm in the afternoon you couldn't even see leaves moving on the trees.
 
Eran's interpretation of the data, makes total sense. With the counter-rotating motors, a failure of one motor will cause the spin of death, until it hits the ground, a spin right, clockwise in other words would be a failure of the motor or ESC counter-clockwise...unless of course it is a completely confused flight controller.
Considering 207 flights I would tend toward the energy to work converter...the motor, the odd noise detected is another significant clue here....a real bummer, sorry to hear about all this.
 
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Eran's interpretation of the data, makes total sense. With the counter-rotating motors, a failure of one motor will cause the spin of death, until it hits the ground, a spin right, clockwise in other words would be a failure of the motor or ESC counter-clockwise...unless of course it is a completely confused flight controller.
Considering 207 flights I would tend toward the energy to work converter...the motor, the odd noise detected is another significant clue here....a real bummer, sorry to hear about all this.

Yes I'm leaning toward this also. I hope DJI sees it the same way.
 
Oh just realized I should have said clockwise motor ...a failing CW motor makes the copter spin clockwise and the opposite for counter clockwise spin...very interested in the DJI's response to this
 
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Eran's interpretation of the data, makes total sense. With the counter-rotating motors, a failure of one motor will cause the spin of death, until it hits the ground, a spin right, clockwise in other words would be a failure of the motor or ESC counter-clockwise...unless of course it is a completely confused flight controller.
Considering 207 flights I would tend toward the energy to work converter...the motor, the odd noise detected is another significant clue here....a real bummer, sorry to hear about all this.


There's so little to go wrong with the motor though.
3 coils, permanent magnets, and some bearings.

Foreign material, workmanship (solder joint, etc.) or ESC seems most likely. No???
 
Yes true...but there is the mechanical component to any motor as well, but that being said, I agree ESC is just as likely, and a faulty ESC motor signal could cause strange noises from the motor.
 
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I feel sorry for you Frederick. Hopefully you get it sorted out and keep up the good work with the video tutorials you are making!
 
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I AM BAFFLED. 207 Flights and never had this happen. All was well as I was flying back. No issues.... then simply spun out of control to the ground. Thankfully it slammed into the neighbors yard... and not their kids or house.

I've called DJI, they sent an RMA and it's been FedExed to DJI in California for diagnostics of the "problem". We'll see I guess. Fingers crossed.

Any input form you guys is welcome as I'm speechless as to exactly what happened. Has anyone had to get a replacement or repair? I'm assuming it'll be quite a while.

Before flight:
Compass: Good
IMU Mod: 1500-ish
Battery Cell Voltages: Equal and Good

Video from the app here:
http://youtu.be/sXzBsKHcBI4View attachment 29341 View attachment 29342 View attachment 29343
Similar thing happened to me the other day. I was flying at 60 feet and p3 just fell out of sky doing top speed. Landed in soft sand right next to family fishing. No damage except for slightly bent gimble arm. Flight recorder showed it spinning out of control. Guy fishy said a black bird came out if nowhere and hit it! Making me paranoid about birds now.
 

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Probably a bad motor or an ESC gone bad . So if you have flied 1 or 1001 flights it does not matter the ESC can fail equally.
 

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