Spin & crashed!

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What went wrong? Compass or Motor/esc failure
After 18 months of hibernation i woke up P3 Adv for a flight.. I didn't re-calibrate compass..
1st flight was ok, changed battery, off for a second flight, after a few seconds noticed the drone camera sudden erratic move. let it in standby, then it started spinning and losing altitude.
Managed to salvage the puppy on a roof, its position was upside down, broken propellers and 1 motor practically not spinning when starting up:

Flight logs show "Motor Blocked" warnings of on both flight. It started spinning out of control when log shows error "Motor is Blocked. Not Enough Force/ESC Error "
Crashed flight however also have compass error..
DJI Go app show ESC error What is the cause of crash? what needs to be changed?
Crashed flight:
 
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Meta4

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What went wrong? Compass or Motor/esc failure
After 18 months of hibernation i woke up P3 Adv for a flight.. I didn't re-calibrate compass..
1st flight was ok, changed battery, off for a second flight, after a few seconds noticed the drone camera sudden erratic move. let it in standby, then it started spinning and losing altitude.
Managed to salvage the puppy on a roof, its position was upside down, broken propellers and 1 motor practically not spinning when starting up:
A short version of the flight data looks like this:

The first indication of a problem is at 0:17.7.
The drone is climbing and the drone starts to rotate clockwise despite the rudder being centred.
The rotating slows and almost stabilises around 0:21.
At 0:34.2 with the rudder still centred, the rotation pauses and then speeds up.
The highest point on the flight is 91 ft at 0:42.4 when the drone starts to lose height despite the throttle being centred and later, pushed upwards.
The fall becomes faster, it spirals, rolls and pitches as it tumbles and falls to earth.
It crashes at approx 0:49.4 and all data after that is garbage because of the crash.

The battery voltage was good and shows that it was not a battery issue.
The spining and falling indicates the loss of a prop or motor.
If all props were attached to the drone (and complete), that suggests a motor (or an ESC that controls the motor.
Broken or unattached props might have happened in the crash.
 
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Gizmoh - any chance of the .DAT file from. the drone itself Much more information in that.

You didn't calibrate the compass after 18 months:(
 
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A short version of the flight data looks like this:

The first indication of a problem is at 0:17.7.
The drone is climbing and the drone starts to rotate clockwise despite the rudder being centred.
The rotating slows and almost stabilises around 0:21.
At 0:34.2 with the rudder still centred, the rotation pauses and then speeds up.
The highest point on the flight is 91 ft at 0:42.4 when the drone starts to lose height despite the throttle being centred and later, pushed upwards.
The fall becomes faster, it spirals, rolls and pitches as it tumbles and falls to earth.
It crashes at approx 0:49.4 and all data after that is garbage because of the crash.

The battery voltage was good and shows that it was not a battery issue.
The spining and falling indicates the loss of a prop or motor.
If all props were attached to the drone (and complete), that suggests a motor (or an ESC that controls the motor.
Broken or unattached props might have happened in the crash.
thanks for investigating. Props were & still solidly attached , any way to know if its ESC or motor issue?
 
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Gizmoh - any chance of the .DAT file from. the drone itself Much more information in that.

Looking at your flight (over so many houses??) there were several battery deviation errors starting at 45.8 where there was a sudden drop in unevenly in voltage.
Then at 49.6 your compass packed up and the battery cells dropped in voltage quite significantly possibly the cause of the speed error.
From that point on the battery was what I think is below their ability to power the drone adequately and unbalanced.

View attachment 115454
The DAT file for the event is most probably erased. As i managed to get the drone the next day only. It stayed powered up until the battery died,so DAT was over-written with newer data whilst wrecked on ground.

Yea it may be the battery, as the 1st flight with another battery had no issue(apart from motor blocked!)
1st flight log:
 
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No that would not erase the .DAT files, in fact they are almost impossible to delete as I've found out recently
- have a look as in there are motor, ESC and every other data.

In Maritious - lucky you!
 
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Fly Dawg

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The DAT file for the event is most probably erased. As i managed to get the drone the next day only. It stayed powered up until the battery died,so DAT was over-written with newer data whilst wrecked on ground.
The .dat's are only overwritten when the aircraft storage is full. However, in this instance I might suspect that the .dat may be corrupted ( Not closed properly due to battery power ).
 
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The .dat's are only overwritten when the aircraft storage is full. However, in this instance I might suspect that the .dat may be corrupted ( Not closed properly due to battery power ).
Storage was full as the drone remained ON for over 2 hours 30 min after crash .
 
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The storage will always show full, about 4Gb, as oldest files are overwritten by new ones. Not sure how much data 2½ hours would generate? FD will know. If more than 4Gb then yes the flight file will probably have been overwrite!
 

Fly Dawg

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Storage was full as the drone remained ON for over 2 hours 30 min after crash .
That question aside. Going back for a closer look at the data, I am starting to wonder if this was an actual aircraft alone issue at all. It could be a combination of the two. The RC looks to be off calibration. Notice below the values of the right stick. Specifically the aileron. It is not enough I don't think to cause a serious issue, however it is possible that being that the offset of the elevator recovered during the flight, the aileron remained offset the entire time. It never went to zero as it should when you release the sticks. Which in turn would provide false inputs to the aircraft. Just throwing that out there as something to consider.

1573141505381.png
 
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That question aside. Going back for a closer look at the data, I am starting to wonder if this was an actual aircraft alone issue at all. It could be a combination of the two. The RC looks to be off calibration. Notice below the values of the right stick. Specifically the aileron. It is not enough I don't think to cause a serious issue, however it is possible that being that the offset of the elevator recovered during the flight, the aileron remained offset the entire time. It never went to zero as it should when you release the sticks. Which in turn would provide false inputs to the aircraft. Just throwing that out there as something to consider.

View attachment 115463

Yes. right stick of my RC is partly broken (pushes inside) while i was modding since earliest days of ownership.. I have been able to use it several times, I doubt this alone would make it spin erratically downwards and lose altitude.
 

Fly Dawg

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I doubt this alone would make it spin erratically downwards and lose altitude.
As do I, but it was worth pointing out. That is all I was doing.
 
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I have flown around 1800m altitude and over 10km distance(not counting return) with this baby..
20191107_201116.jpg
 

Meta4

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You didn't calibrate the compass after 18 months:(
There's no problem with that.
The drone's own magnetic fields don't change unless you modify or rebuild the drone so there shouldn't be any need to recalibrate.
I still haven't calibrated anything on my 3 year old P4 pro.\ and it flies perfectly.
 
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I've just had mine back after an argument with the tree and the repairer insisted that I calibrated everything before flying.
 

Fly Dawg

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You didn't calibrate the compass after 18 months
As mentioned by META4....No need to do so unless necessary. It's been almost 3 years for my bird. No issues.....
 
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Your drone was repaired. It required calibration. In OP's case it did not.
I have to say that after 18 months lying on a shelf I would calibrate. In fact t I calibrate at any new location I go to. It's an individual choice.]
]
At no time was he flying above 90 feet over all those houses. I wonder if there was some sort of interference somewhere along the route?
He started to lose height at 0.43 and just steadily dropped to the ground.
At the latter part of the flight the battery cells were showing some deviation but still at 95% capacity.

I'd still like to see the data file if it is still there.
I am in a steep learning curve analysing data and would be interesting to see what the ESC's and motors were doing.
 
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