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Just put my drone in the lake now I'm trying to find it need help

here you are then... hopefully this will shed some light so others may learn from my f up
 

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here you are then... hopefully this will shed some light
Here's what that data looks like: DJI Flight Log Viewer - PhantomHelp.com
A quick look shows one disturbing thing in the data.
Towards the end of the flight, you climbed from 44 ft to 107 ft and left the throttle untouched from 1:08.5.
The Mavic held altitude (as it should) while you went fast forward and used left and right rudder until 1:32.1 when the Mavic started steadily losing height.
Five seconds later the height was showing 43.6 feet and the data stops.
I don't believe the rudder movement caused the issue as the drone held altitude for 24 seconds of similar movement just before this.
The pitch, yaw and roll data doesn't show any sudden change which would indicate a sudden onset problem.

The yaw data is tricky to follow because of the on/off rudder inputs so it's not clear if it was tending to spin as it lost height.
The sudden end of data corresponds to a sudden loss of power.

@sar104 likes a challenging puzzle.
This one might be something for him to look closer at the data.
 
Would this matter?? at the beginning of the flight?

**warnings:Mobile device CPU fully loaded. Related performance will be affected.**
 
Did you see your Mavic nosedive into the lake or are you assuming that's what happened?
 
I did not see the last 10+ seconds of the flight, that was my "distracted" pilot failure. My last split second look at the iPad were ripple's of water just before I realize I made a fatal mistake.

I actually thought I was high enough to just let go of the sticks and it would stop and hover and I would go back to "P" mode and finish off a lazy flight.

I never thought I was out of control by any means.
 
I was hoping someone with lots a flight data knowledge could shed some light. when I looked at it, I didn't see much differance than what I thought I experienced. BUT! I have very little to no experience reading that data... wait... NONE is what I have.
 
Did you see your Mavic nosedive into the lake or are you assuming that's what happened?
Given that it lost 63 feet of altitude in 5 seconds despite no throttle input, it's pretty clear that it entered the water.
I did not see the last 10+ seconds of the flight, that was my "distracted" pilot failure. My last split second look at the iPad were ripple's of water just before I realize I made a fatal mistake.
What fatal mistake?
The data shows no operator input that would have caused the incident.
I would think it is a good case for a warranty claim.
Maybe it collided with something?
A collision would show in the data, but the pitch, roll and yaw data show no evidence of a collision.
They do show 5 seconds of uncontrolled descent following steady controlled flight.
 
iven that it lost 63 feet of altitude in 5 seconds despite no throttle input, it's pretty clear that it entered the water.
Yep, it entered the water for sure. I was just wondering if the OP saw it go down.
 
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I was hoping someone with lots a flight data knowledge could shed some light. when I looked at it, I didn't see much differance than what I thought I experienced. BUT! I have very little to no experience reading that data... wait... NONE is what I have.
Looking more closely at your flight data, I see another anomaly.
The last few seconds of the flight track shows an erratic fine sawtooth pattern rather than smooth curves.
Just another indication that something was not at all normal.
I'm not sure what would cause it.
Maybe losing a propeller blade ?? (just a guess)
This shows in the last 73 metres of the flight - about 3 seconds.
i-256qpr2-L.jpg
 

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I was hoping someone with lots a flight data knowledge could shed some light. when I looked at it, I didn't see much differance than what I thought I experienced. BUT! I have very little to no experience reading that data... wait... NONE is what I have.
If you were looking to recover the drone, the point of impact is probably another 150 feet (approx) further to the west/southwest of the last recorded location - almost halfway back to shore from the last data point.
 
Unfortuinitly that part of the lake is around 30'. Lots of florida's smaller lakes are sink holes and have depth and the water below the15' mark is DARK. I feel recovery would be futile.

WARRANTY? never thought that was an option
 
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WARRANTY? never thought that was an option
If the drone is less than 12 months old and there is evidence of a DJI issue, warranty should be an option.
I once had a Phantom replaced even though the drone was lost in deep water.
The logs clearly showed the cause of the incident and DJI sent me a new drone.
 
The IMU completely lost the plot here. If you compare what I think is basically barometric altitude (OSD_height) with what the FC/IMU thought was happening vertically, by integrating the vertical velocity with respect to time, you get the following:

altitude.png

These track pretty well (as they should) until 92 seconds, at which point the IMU vertical speed goes in the wrong direction. Thinking that it is in an uncommanded ascent, the FC cuts motor power (inferred) and the aircraft goes into rapid descent, reaching around 10 m/s before the IMU looks like it starts to recover. That's too late to prevent splashdown.

Summary - the IMU or the FC failed in the vertical plane. There was no throttle input and this was not pilot error. Should be covered under warranty.
 
It's about as old as my membership here about 4 months.

So... in your opinion (yes just an opinion) it was not pilot error?
 
It's about as old as my membership here about 4 months.

So... in your opinion (yes just an opinion) it was not pilot error?

If you are asking me, it's not an opinion - it is a clear conclusion from the log data. Not pilot error. This was equipment failure, either hardware or software.
 
If you are asking me, it's not an opinion - it is a clear conclusion from the log data. Not pilot error. This was equipment failure, either hardware or software.


I just shared that news with my bride.... "you need to thank those guys, I was going to make you suffer" :)
 
It's about as old as my membership here about 4 months.

So... in your opinion (yes just an opinion) it was not pilot error?

Looks like very good news dude. I would hope a new drone will be making its way to you in the near future. DJI will see the same flight data and that is that as they say as your warranty will stand firm.

A great outcome for a very unlucky event!
 
Well I just made first contact with DJI... we will see how it plays out.

AND! in the words of my lovely bride... THANK YOU ALL SO MUCH!
 
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