P3 Pro Fell From Sky Today

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Ugh! Terrible! Was hoping someone smarter than me could look at my flight log and see anything out of the ordinary. The drone is pretty busted up right now.

I lifted off with a Safe to Fly message and a green GPS icon with lots of signal strength in the P mode. Flew about 35 feet up and switched to F mode. Tried to put it in follow me mode but got an error saying the GPS signal wasn't strong enough to enable follow me mode. I tapped the icon a few more times to try again, hoping each time it had achieved a lock.

Then, for no apparent reason (at least, to me!) the drone pitched to one side, spun in wild circles, and spiraled downward and crashed. 3 props were on and 1 was nowhere to be found. The gimbal is bent and the camera is broken off entirely with a torn ribbon cable.

When I put a battery in the drone, it powers on but I get a weird buzzing noise from the bottom (maybe that was there before and I didn't notice... now I'm a bit paranoid) and also, if you try to turn the drone off by tapping the battery once and then again and holding down, the second "hold down" just leaves the battery blinking red. You have to hit it again to turn it off.

If I look at my flight record in the DJI Go app, at the moment the drone starts spiraling out of control, I see a red dot on the bottom right of the screen, whereas before the crash it was blue and up at the top of the screen. I am not sure what this means.

I did pull the sticks down but I did so after the drone hit the ground, in order to keep the motors from burning out in the bush it hit (I don't know if it stops automatically or not). Either way, I wasn't touching the controls AT ALL when the Phantom started spiraling.

I did hand tighten the props, but I kind of think a propeller flew off, given that I can't find it and that it didn't just fall straight down.

I should also note that the firmware is totally updated. I had a perfectly normal flight a few hours beforehand.

Here is the Healthy Drones link: HealthyDrones.com - Innovative flight data analysis that matters

Any thoughts are much appreciated. Getting in touch with DJI tomorrow.
 

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I see from your log that you did not engage follow me mode at least on one occasion because you where below 10 meters, also you have a few warnings about a motor being obstructed. But best wait for the more experienced guys to come along and have a look at your log.

Flack
 
Thanks for the input! I climbed up higher because I was under the ceiling and then tried but got the GPS warnings. The motor obstruction warnings came when it was on the ground trying to spin but stuck in foliage.

I see from your log that you did not engage follow me mode at least on one occasion because you where below 10 meters, also you have a few warnings about a motor being obstructed. But best wait for the more experienced guys to come along and have a look at your log.

Flack
 
Was it windy? The wind speed on healthy drones shows a max wind gust of 68.8 MPH, 110.8 kmh with avg speeds of 19 mph, 30.6 kmh. I am not sure how accurate that is.
 
Yeah, the wind speed gust would have blown me over and was not indicative of the wind levels at all. The first wind speed reading was 14mph, which is probably more accurate, but even then it wasn't that windy. I think the average wind speed of 26 mph or something is a measurement of the first one and the "gust," and the gust reading was taken a second or two AFTER the drone started spinning, so I think it was influenced by a sudden change in position of the Phantom.

Why do props spin off and is damaged caused by that something that's ever covered under warranty?

Another question is, even if it lost GPS signal, shouldn't it just switch to ATTI and hover and be blown by the wind? Because it didn't hover, it rotated like I had the left stick pushed all the way to one side, and then fell toward the ground in spirals. As far as I can tell, nothing about GPS signal strength would cause this...?
 
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Was it windy? The wind speed on healthy drones shows a max wind gust of 68.8 MPH, 110.8 kmh with avg speeds of 19 mph, 30.6 kmh. I am not sure how accurate that is.
Not an expert on reading healthy drone but possibly bad GPS signal could have created a bogus wind speed. But, it is next to the water.
 
pitched to one side, spun in wild circles, and spiraled downward
sounds like prop off to me. what about props? did you maybe just mounted props before flight?
 
I had mounted the props just before flight, spun them down, and gave them a little bit of hand tightening. The machine was about 5 days old or so, with 4:45 of total flight time.

Here are DropBox links of the DAT files that were created at the time of the crash:

Dropbox - FLY054.DAT
Dropbox - FLY055.DAT
Dropbox - FLY056.DAT

For some reason, there are several DAT files at the time of the crash, which I don't understand.

Thanks guys. I can't believe the amount of technology in these little machines.
 
Thanks for posting the Dat files:
For some reason, there are several DAT files at the time of the crash, which I don't understand.
Each time you turn on and off the batteries in the P3 it will record a Dat file. The crash log is FLY054 and FLY056 is where you turned on the battery to retrieve the DATs .
In below graphs its quite clear that just before you lose altitude (1st chart) the Right Front Motor load goes to 0 (2nd chart).
At that same time the Right Front Motor speed increases to 1000 (3rd chart). Thats typical of a prop that has flown off.
All other motor loads (graphs 4 to 6) are at that time point still indicating normal values. Their load increases at impact (due to the props still on) where altitude graph is horizontal again.
upload_2016-1-8_21-13-30.png


Here's video of that log
 
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what are you using for the charts and the youtube video to get the data shown like that ?
 
Sorry about your crash. I see you are using an iOS device. Is it GPS enabled? If a wifi only iPad, that would be your "weak GPS" issue when trying to engage Follow Me.
 
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Mine did the the same thing on Christmas Eve. Only 5 flights on the drone.

I could not retrieve the the dat files, the p3p was too damaged from 200' landing onto rocks.

Being new to this hobby can I get any helpful data off the controller or iOS app?

Is a parachute an option that can help prevent some major damage in the event a motor stalls or a prop falls off?
 
Hand tight is no good. Due to numerous prop issue I have seen others have, I always use the prop tool and tighten the props past the snug point trying to stay consistent with each one.

I also spent a lot of time looking over your data. Your problem of coarse should not have happen, but it did. The reasons I believe contributed to it was trying to do follow me at the height it was, no compass calibration, too close to home point. Other then that everything appeared just as you said it did. Your A/C did not drop that far. A compass issue will also drop the a/c to one side. If a prop comes completely off the a/c will drop and not fly in circles.
 
Why don't just use metal hub props? I think the problem is the new dji props with plastic hubs don't lock in as the metal hub ones.
 
Why don't just use metal hub props? I think the problem is the new dji props with plastic hubs don't lock in as the metal hub ones.
Terrible recommendation. DJI changed the PS3 to composite because of active breaking. Metal does not contract as well as composite so it will allow the prop to spin off under active braking.

Ever try to spin a nut off of a bolt? Easy. Ever try to spin a look locking nut off?
 
Terrible recommendation. DJI changed the PS3 to composite because of active breaking. Metal does not contract as well as composite so it will allow the prop to spin off under active braking.

Ever try to spin a nut off of a bolt? Easy. Ever try to spin a look locking nut off?
It was a question not a recommendation ;)
 

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