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PGM
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PGM Posted at 2018-1-10 21:21
Thank you for your assistance in this Case: Case Number: CAS-1375661-C0X0T9

I noticed that on Case Number: CAS-1375661-C0X0T9    it shows, Service Type as: Repair and Data Analysis: Not required. Shouldn’t this show, Service Type: Warranty and Data Analysis: Recommended?
2018-1-10
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The Speed Error is an ESC error and is probably indicating a failing ESC. You should never fly with this error, even if it goes away.
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Jenee 2 Posted at 2018-1-10 22:04
The Speed Error is an ESC error and is probably indicating a failing ESC. You should never fly with this error, even if it goes away.

Agreed, Compass error could also suggest there's something wrong with the ESCs. There was no persistent ESC error ongoing, but I will certainly ground my Phantom 4 Pro Obsidian if I ever see this error again.
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which software you have in obsidian ?
2018-1-11
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which software you have in obsidian ?
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PGM
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Phantom 4 Pro Obsidian With the latest firmware installed.
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Aircraft Firmware : V 01.05.0300 ?
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PGM Posted at 2018-1-10 21:21
Thank you for your assistance in this Case: Case Number: CAS-1375661-C0X0T9

Did you paint the drone or is that the Obsidian?
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Hi PGM,

One of my drones that had just been thru a maintenance check (so it should have had no physical issues) has also crashed on the latest firmware. With the other slew of issues with this upgrade, I am curious if it was actually your drone's fault, or the latest update.
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dkotinsky Posted at 2018-1-11 14:53
Did you paint the drone or is that the Obsidian?

Obsidian Pro
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ROKI Posted at 2018-1-11 11:42
Aircraft Firmware : V 01.05.0300 ?

If Version:V 01.05.0300 is the latest version, then Yes . I kept my Bird up to date. When I received a version update notice, I updated.
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MaintenanceKing Posted at 2018-1-11 15:06
Hi PGM,

One of my drones that had just been thru a maintenance check (so it should have had no physical issues) has also crashed on the latest firmware. With the other slew of issues with this upgrade, I am curious if it was actually your drone's fault, or the latest update.

At this time all evidence points to ESC, Motor failure. I can not really say if the latest firmware update could have caused this. In Design, the firmware most likely interacts with ESC and ESC to the motor but understanding the dynamics of this firmware update would take some study.
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Tracking Phantom 4 Pro:  Scheduled Delivery: To DJI in Los Angeles, California is Monday, 01/15/2018 - by the end of day: via UPS.
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Bashy
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Scary seeing this can happen
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I've been going over the flight data for the past few hours and this one is a doozy.

As an observation, your flight control movements during this flight are very abrupt, quickly going from zero to full deflection.  This results in violent movements, including full acceleration to maximum braking in short order.  This has been known to crack airframes and throw props on various aircraft.  We regularly see your pitch and roll angles at 40° or more quite frequently, which is the limit of controlled flight for P4.

I examined your comments and tried to match them to the flight record.
While Flying I Received Low Battery Warning,
There was a low power Go Home initiated at about 36%.  This would be due to the rate of power consumption, and a calculated safe return home with sufficient reserve from that point.

Returning GO Home initiated,
I Canceled RTH and Manually Returned (sport Mode),

While there is nothing wrong with flying it back home normally, resuming a maximum power Sport mode flight home on a low battery is questionable.  Fortunately you were close enough and the battery didn't go anywhere near critical, but it is something to keep in mind in future.  It would be more sensible to fly it back gently once a low power warning is initiated.
  
High Wind Velocity warning, (not uncommon) it was not a windy day
We hear this one all the time.  You were standing on the ground at the home point.   You can comment on the wind strength at your location.  You are likely to have no idea what the wind is doing at the aircraft's position and altitude.  It is very common to have high winds a few feet above the ground, where it is calm.  I did not see any wind error in the flight record.

Received Warning: Weak GPS Signal,
Received Warning: Ultrasonic System Error: Land as soon as possible,
Received Warning: Motor Obstructed,
Received Warning: Gimble Roll Reached Movement Limit,
The Controls Auto Changed to Atti Mode,
Received Warning: Compass Error: Exit P-GPS Mode:
Received Warning: Weak GPS Signal. Positional accuracy may be compromised.

These warnings are typical of an aircraft that is in the process of tumbling and crashing.
  
Phantom 4 Pro goes into a Sudden uncontrollable clockwise spiral inverting several times and Registered horizontal speed of 108.2 mph, 128 Ft. off the ground.
I notice at around 18 minutes into the flight, your incident occurs.  There appears to be a clockwise spiral, however there is a distinct manual left stick right and right stick down command issued and held for seven seconds and consistent with the flight path recorded.

Spinning and crashing, all control over the Phantom 4 Pro was lost, The Phantom 4 pro crashed down into cedar trees in a vacant lot next to us, sustaining damage to housing, props, Camera, gimbal, ex. I was in complete Shock that this could ever happen. There were no obstacles or collisions, no bird strikes, weather was clear blue skies, no wind ex. Just sudden uncontrollable clockwise spinning. All of the Errors and crash happened within seconds of each other and the video and control inputs show hover, descending and then sudden loss of control.
The issue is what initiated this crash sequence.  Up until 18 min the flight was pretty normal and predictable.  The flight log shows you held maximum down, rotate right, and move backwards on the sticks at all times during the crash.  That is 3 stick positions out of 4 on the way to a CSC by the way.

spreadsheet.png

Referring to the flight record alone, I'd question the accuracy of the altitudes recorded.  It started in sync with the VPS altitude, but drifted further and further apart during the flight.   The last GPS location recorded does not line up with the last point of the kml data.  It seems to continue on further into the trees and comes to rest against a fence.  Can you confirm on the map/picture where the aircraft was recovered?   

crash.png
The post-crash altitude appears to go to around -92ft, which is impossible.  The land changes only a couple of feet between home and the crash site, and is typically flat.  This is in contrast to your claim of "horizontal speed of 108.2 mph, 128 Ft. off the ground".  Typically the crash speed was no more than 40mph for short instances whilst tumbling.  We can see the tree line is no more than 10-20ft.

north.png south.png

I'm going to suggest that the aircraft was far closer to the ground than indicated, maybe 20 feet?  If we reduce the indicated altitude by 100feet, to account for the "negative altitude" recorded in the crash, things start to look more natural and explainable.  We can see around 17 min the VPS sensor records an altitude of about 10-12 ft while zooming along at 40mph, while the barometer records 438feet!  As expected the VPS sensor readings cut out when the altitude increases beyond its (40ft?) limit.  To me, the VPS sensor is providing more reliable readings than the barometer.

If we extend this to 18 minutes and the crash starts, and looking at the map, I suggest the aircraft clipped and "bounces off" the side of the house at the back corner at 10-20ft altitude.  This resulted in a sudden violent nose pitch down at -40° briefly upon impact, followed by a reactionary +40° nose pitch up to counter.  At the same time we see the airframe roll +25° through -35° over the next 3 seconds. (See pitch/roll columns from 18:00 onwards, this is recorded exactly as the described "bump" would react).  The rest of the path and various rolls and tumbles would coincide with clipping and crashing into the tree tops in the image.  At the reported altitudes, there is nothing to hit, clip or fall through that would cause these rolls and tumbles.   It is more reasonable and rational to attribute them to interaction with the trees themselves, as the movements correspond with locations of treelines.  
It is possible a prop blade  or tip could have snapped off at the initial location, initiating a spiral tumble -- try a thorough search  at the corner of the house, and inspect the wall for impact damage.  

From the pilot's perspective, it would appear the flight was normal followed by an inexplicable spin and crash, especially if he believed he was flying at hundreds of feet and not close to the ground.  In reality, the aircraft clipped something and tumbled out of control.

I'd suggest the reason for the incorrect altitude needs to be investigated.  It started in sync at takeoff, but was wildly incorrect at the point of the crash.  Had the aircraft been taken out of an airconditioned/pressurised environment immediately before flight?  Was the temperature wildly different?  This could explain a drifting barometric pressure and a change in reported altitude.

Normally I'd consider this to be a case of pilot error, having flown it into the side of his house on the way home.  However his instrumentation seems to be faulty and misrepresenting the true altitude.  Perhaps if it were left to its own devices to perform it's Go Home or RTH by itself, this wouldn't have happened (or if it did, it would be 100% a DJI responsibility).  I would suggest DJI should provide warranty if the crash is due to faulty instruments.  You are fortunate that you can fall back to your own insurance if you are not satisfied.  If DJI repair it or replace it with a refurbished item, you will still have 100% warranty and it should be no different than a brand new one.  It may be replaced with a brand new one due to it's rarity and age.  If you are particularly concerned with this, make an insurance  claim and get paid out or get it replaced by a brand new one.

I still have the DAT file to examine.  It has a greater number of parameters and data points to examine so it may take a while...  I'll see if it reveals any clues.

EDIT: I just got the video to download and play, this does NOT support my altitude theory at all, although it does look a lot closer to the ground than 200 feet, and it doesn't explain the negative altitude during the crash.



I've examined the DAT file recovered from inside the aircraft.  It shows a failure of the right front motor immediately prior to the spiral commencing.  I haven't been able to see what caused the stoppage, although it does not look like a prop failure.  The associated ESC temperature dropped and was cooler than the others, so we can assume it was not feeding the motor like the remainder were.  This suggests the motor was not rotating;  with a damaged prop it would still be trying to rotate.
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endotherm Posted at 2018-1-11 23:29
I've been going over the flight data for the past few hours and this one is a doozy.

As an observation, your flight control movements during this flight are very abrupt, quickly going from zero to full deflection.  This results in violent movements, including full acceleration to maximum braking in short order.  This has been known to crack airframes and throw props on various aircraft.  We regularly see your pitch and roll angles at 40° or more quite frequently, which is the limit of controlled flight for P4.

Endotherm as usual extremely thorough and detailed

Based on your updated info are you still keeping with the assertion that it hit the house?  If so, would this have contributed to or caused the motor failure?
Thanks
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New Case Video's and Links

Phantom 4 Pro Correct Takeoff Location
https://www.dropbox.com/s/xm7hg3 ... 20Location.mp4?dl=0


Phantom 4 Pro Malfunction and Recovery Location
https://www.dropbox.com/s/mw8pk4 ... alfunction.mp4?dl=0

Phantom 4 Pro Live Video of Crash slowed for viewing
https://www.dropbox.com/s/b1akbp ... %20Failure.mp4?dl=0
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endotherm Posted at 2018-1-11 23:29
I've been going over the flight data for the past few hours and this one is a doozy.

As an observation, your flight control movements during this flight are very abrupt, quickly going from zero to full deflection.  This results in violent movements, including full acceleration to maximum braking in short order.  This has been known to crack airframes and throw props on various aircraft.  We regularly see your pitch and roll angles at 40° or more quite frequently, which is the limit of controlled flight for P4.

An excellent analysis as always, I am impressed again with the amount of time and effort you must put into these. You have more or less proven what I suspected with the DAT file.

My only comment would be that on the P4 series now the CSC does not stop the motors in flight. This is done left stick down and towards centre and hold RTH button operated, and there may even be a three second delay built in.
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endotherm Posted at 2018-1-11 23:29
I've been going over the flight data for the past few hours and this one is a doozy.

As an observation, your flight control movements during this flight are very abrupt, quickly going from zero to full deflection.  This results in violent movements, including full acceleration to maximum braking in short order.  This has been known to crack airframes and throw props on various aircraft.  We regularly see your pitch and roll angles at 40° or more quite frequently, which is the limit of controlled flight for P4.

Thank you for your detailed analysis,
I do have personal insurance on the Phantom 4 Pro Obsidian, I can assure you that if I would have clipped any obstacle and Pilot error was the cause, then I would have just hung my head and filed an insurance claim and Purchased a new Phantom 4 Pro Obsidian; but this simply is not the case.
I do feel confident in my ability to fly the drone and did not fly the phantom 4 Pro outside of its performance spec’s.  The battery was at 25% at the Home point before the malfunction and any stick input after flight time 18:00 I feel was covered by FAA part 91, in short (trying to get control of an uncontrollable aircraft.) People trust in their equipment and should feel confident in its ability’s and their ability to control it. This malfunction could a have been a lot worse. The Diagram you provided from the DAT file shows that all pitch and roll angles were within DJI performance range, below (Max Tilt Angle S-mode: 42°) before the malfunction occurred. In the future I will heed your advice about RTH and DJI’s responsibility when using RTH. At this point, I show more evidence of ESC, Motor Failure and I appreciate you chiming in to Help.

Endotherm: “I just got the video to download and play, this does not support my altitude theory at all, although it does look a lot closer to the ground than 200 feet, and it doesn't explain the negative altitude. I've examined the DAT file recovered from inside the aircraft.  It shows a failure of the right front motor immediately prior to the spiral commencing.  I haven't been able to see what caused the stoppage, although it does not look like a prop failure.  The associated ESC temperature dropped and was cooler than the others, so we can assume it was not feeding the motor like the remainder were.  This suggests the motor was not rotating; with a damaged prop it would still be trying to rotate.”

Please see new videos added as they may also lend aid.
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Genghis9 Posted at 2018-1-12 08:39
Endotherm as usual extremely thorough and detailed

Based on your updated info are you still keeping with the assertion that it hit the house?  If so, would this have contributed to or caused the motor failure?

The Phantom 4 pro did not come into contact with any obstacle this flight or any other flight I have taken.
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Note to Self and All Drone Pilots, It is good practice to record your takeoffs and landings as they will lend aid if anything like this ever happens to you.
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Genghis9
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PGM Posted at 2018-1-12 17:31
The Phantom 4 pro did not come into contact with any obstacle this flight or any other flight I have taken.

Well the analysis is not complete, and he has asked for clarification on where the drone impacted the ground (i.e. final landing spot) as compared to the info he has.  However, regardless the science of matching the data with the environment is not exact, but thus far I stand by his understanding of what he is seeing in the data.  Whether it happened as he is surmising, based on the data, or the way you experienced it, it appears there was something that caused an obstruction.  Since the altitude is off by a significant amount that could possibly be throwing off the overall analysis too.  
Ultimately it will come down to what DJI thinks and determines.  Endotherm is one of the best at this and the most thorough, however, there are others that can either corroborate or dispute his findings.  Labroides is another that I would trust if you really want a second opinion.
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Aardvark Posted at 2018-1-12 14:19
An excellent analysis as always, I am impressed again with the amount of time and effort you must put into these. You have more or less proven what I suspected with the DAT file.

My only comment would be that on the P4 series now the CSC does not stop the motors in flight. This is done left stick down and towards centre and hold RTH button operated, and there may even be a three second delay built in.

Aardvark after much discussion on this issue, I did a test of each on my P4P (not in flight of course).
Indeed CSC still works on a P4P as well as the stick rth combo method, and while I found an ever so slight difference in motor cutoff time (I would not want to live on it or bet my drone on it) both cutoff the motors nearly as fast and the CSC did not show a 3 second delay.  Based on some further research it seems the 3 seconds only occurs for left stick full down and hold in shutting down the motors.  The manual v1.4 page 59 still supports CSC use on P4Ps too.
Respectfully

EDIT: While I did not test this in fligth (for obvious reasons) I'm certain the CSC will still work in flight.  I will devise a test that fools the craft in thinking it is airborne and get back to you, just to be certain.
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Genghis9 Posted at 2018-1-12 17:41
Well the analysis is not complete, and he has asked for clarification on where the drone impacted the ground (i.e. final landing spot) as compared to the info he has.  However, regardless the science of matching the data with the environment is not exact, but thus far I stand by his understanding of what he is seeing in the data.  Whether it happened as he is surmising, based on the data, or the way you experienced it, it appears there was something that caused an obstruction.  Since the altitude is off by a significant amount that could possibly be throwing off the overall analysis too.  
Ultimately it will come down to what DJI thinks and determines.  Endotherm is one of the best at this and the most thorough, however, there are others that can either corroborate or dispute his findings.  Labroides is another that I would trust if you really want a second opinion.

Please see #57 and #60 Endotherm's EDIT to initial analysis. I believe he finds motor failure to be the cause as we all initially suspected based upon the facts, including the video, thanks again for your help.
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PGM Posted at 2018-1-12 17:52
Please see #57 and #60 Endotherm's EDIT to initial analysis. I believe he finds motor failure to be the cause as we all initially suspected based upon the facts, including the video, thanks again for your help.

Yes saw that, this is what I meant about analysis not complete.  There is a tremendous amount of data there and it is tedious, to say the least, to go over in just a few hours.  I'm sure once he goes over it some more he will refine his findings, he always does.  The altitude error is one aspect that needs to be resolved at least to the extent it can provide a logical explanation or malfunction or both.
Agreed motor failure is in your favor, if no mitigating cause can be determined.  DJI will cover the history of your bird's flight ops that is available on board to check and see if you ever did anything that should not have been done or that may have contributed to the error/malfunction(s) that are determined.
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Genghis9 Posted at 2018-1-12 17:47
Aardvark after much discussion on this issue, I did a test of each on my P4P (not in flight of course).
Indeed CSC still works on a P4P as well as the stick rth combo method, and while I found an ever so slight difference in motor cutoff time (I would not want to live on it or bet my drone on it) both cutoff the motors nearly as fast and the CSC did not show a 3 second delay.  Based on some further research it seems the 3 seconds only occurs for left stick full down and hold in shutting down the motors.  The manual v1.4 page 59 still supports CSC use on P4Ps too.
Respectfully

No need to risk your aircraft, try it on the 'Academy' flight sim', it works well. DJI Go 4 also has an choice (at least on the P4) where the option to cut off the motors in flight can be enabled or disabled. When enabled there is a three second delay to motor cut out using left stick & RTH method. Whereas both sticks down and in (or out) merely descends the aircraft in a nice spiral until you let go of sticks, at which point it hovers.
The combined stick command will cut the motors if aircraft on ground (that's what P59 refers to, 'when the aircraft has landed').
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Aardvark Posted at 2018-1-12 18:29
No need to risk your aircraft, try it on the 'Academy' flight sim', it works well. DJI Go 4 also has an choice (at least on the P4) where the option to cut off the motors in flight can be enabled or disabled. When enabled there is a three second delay to motor cut out using left stick & RTH method. Whereas both sticks down and in (or out) merely descends the aircraft in a nice spiral until you let go.
The combined stick command will cut the motors if aircraft on ground (that's what P59 refers to, 'when the aircraft has landed').

Well I see that as suspect, because...
1st I actually had to use the left stick rth button while my first P4P was still in the air getting caught up in a tree, shutdown happened immediately, no 3 second delay...not sure what rule set the sim is using but it is not following what is true in real practice

2nd pg 59 only says after landing, not that you must have landed, for it to work.  Yes, it may be splitting hairs but I'm not so convinced.  I will proceed with my test, securely for sure, to determine exactly what is what here.

Respectfully
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PGM Posted at 2018-1-12 17:52
Please see #57 and #60 Endotherm's EDIT to initial analysis. I believe he finds motor failure to be the cause as we all initially suspected based upon the facts, including the video, thanks again for your help.

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Genghis9 Posted at 2018-1-12 18:41
Well I see that as suspect, because...
1st I actually had to use the left stick rth button while my first P4P was still in the air getting caught up in a tree, shutdown happened immediately, no 3 second delay...not sure what rule set the sim is using but it is not following what is true in real practice

Another one to try is (props off) with motors idling turn P4 aircraft upside down, should be immediate motor shut down.
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Aardvark Posted at 2018-1-12 18:47
Another one to try is (props off) with motors idling turn P4 aircraft upside down, should be immediate motor shut down.

Excellent idea, I will consider it and do so if possible
As long as I can be convinced that it is reflecting reality I will conduct the test
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It was a clear, Calm, Beautiful Day for flying

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Genghis9 Posted at 2018-1-12 08:39
Endotherm as usual extremely thorough and detailed

Based on your updated info are you still keeping with the assertion that it hit the house?  If so, would this have contributed to or caused the motor failure?

I am absolutely convinced it did not hit the house!  That description was based solely on examining the flight path and the position relative to the house, followed with pitching and rolling consistent with a "bump" and clipping the top of the treeline.  I felt it was a reasonable hypothesis in the circumstances, considering there were doubts with the altitude data and final GPS coordinates.  Initially there was some sort of technical problem that prevented me from downloading and seeing the flight video, but I was able to view it after posting the analysis.  It clearly shows it was well above the house, and my hypothesis of it being close to the ground was wrong.  I tried to highlight this revised observation as a footnote.  I perhaps should have edited the post to remove the theory, but there still remained doubts as to the accuracy of the altimeter, and I left it.

Analysing the DAT file clearly shows a problem with the front right motor/controller.  I have no doubt DJI would cover this under warranty.  They will analyse exactly the same file and come to the same conclusion.  I'd put it down to dumb luck -- some new electronic components like the ESC will fail after a short time.  Following the "bathtub curve of failure", some components will fail early in life or perform faultlessly for considerable time, with high failure rates at end of life.
bathtub.png

Forgive me if I miss some of the nuances of the P4 firmware (e.g. inverted flight, CSC operation etc) as I don't own one.  However 99% of the operation is similar throughout the Phantom series, which allows me to analyse and understand their records.
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Genghis9 Posted at 2018-1-12 17:41
Well the analysis is not complete, and he has asked for clarification on where the drone impacted the ground (i.e. final landing spot) as compared to the info he has.  However, regardless the science of matching the data with the environment is not exact, but thus far I stand by his understanding of what he is seeing in the data.  Whether it happened as he is surmising, based on the data, or the way you experienced it, it appears there was something that caused an obstruction.  Since the altitude is off by a significant amount that could possibly be throwing off the overall analysis too.  
Ultimately it will come down to what DJI thinks and determines.  Endotherm is one of the best at this and the most thorough, however, there are others that can either corroborate or dispute his findings.  Labroides is another that I would trust if you really want a second opinion.

The clarification required for the final resting place is no longer required.  I am confident it ended up against the fence where I have placed the drop pin.  The reason it looks odd is that the flight path continues "uderground" due to those negative altitudes, and we don't see the continuation of the line to the drop pin.

Rather than a motor obstruction, I'd suggest it was an ESC failure.
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endotherm Posted at 2018-1-13 03:34
I am absolutely convinced it did not hit the house!  That description was based solely on examining the flight path and the position relative to the house, followed with pitching and rolling consistent with a "bump" and clipping the top of the treeline.  I felt it was a reasonable hypothesis in the circumstances, considering there were doubts with the altitude data and final GPS coordinates.  Initially there was some sort of technical problem that prevented me from downloading and seeing the flight video, but I was able to view it after posting the analysis.  It clearly shows it was well above the house, and my hypothesis of it being close to the ground was wrong.  I tried to highlight this revised observation as a footnote.  I perhaps should have edited the post to remove the theory, but there still remained doubts as to the accuracy of the altimeter, and I left it.

Analysing the DAT file clearly shows a problem with the front right motor/controller.  I have no doubt DJI would cover this under warranty.  They will analyse exactly the same file and come to the same conclusion.  I'd put it down to dumb luck -- some new electronic components like the ESC will fail after a short time.  Following the "bathtub curve of failure", some components will fail early in life or perform faultlessly for considerable time, with high failure rates at end of life.

While, as usual, I don't fully understand the technical elements, I understand your explanation.  Thanks for making some sense of the complicated!
2018-1-13
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Genghis9
Captain
Flight distance : 961 ft
United States
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endotherm Posted at 2018-1-13 03:57
The clarification required for the final resting place is no longer required.  I am confident it ended up against the fence where I have placed the drop pin.  The reason it looks odd is that the flight path continues "underground" due to those negative altitudes, and we don't see the continuation of the line to the drop pin.

Rather than a motor obstruction, I'd suggest it was an ESC failure.

OK not necessarily motor failure but ESC failure.
I need to ask, I have a kindergarten level understanding of what an ESC is and that is pushing it and the manual does not explain it if at all.
SO, what in the Sam Hill is an ESC and what does it do?
What does it stand for?
Thanks!
2018-1-13
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ROKI
lvl.4

Croatia
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Which is the maximum distance you have reached obsidian ? PGM
2018-1-13
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endotherm
Captain
Flight distance : 503241 ft

Australia
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Genghis9 Posted at 2018-1-13 06:00
OK not necessarily motor failure but ESC failure.
I need to ask, I have a kindergarten level understanding of what an ESC is and that is pushing it and the manual does not explain it if at all.
SO, what in the Sam Hill is an ESC and what does it do?

https://www.dji.com/newsroom/news/inside-a-drone-esc

In a nutshell, the Electronic Speed Controller is a silicon chip that takes a low voltage command signal and amplifies and translates it into the correct voltage and high current  to control the motor.  Each motor has one.   Theoretically, an ESC could fail but the motor can still be monitored for rotation speed, therefore leading to the conclusion the controller failed, and the motor was not seized or obstructed until it hit a tree.
2018-1-13
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PGM
lvl.3
Flight distance : 57146 ft
United States
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endotherm Posted at 2018-1-13 18:01
https://www.dji.com/newsroom/news/inside-a-drone-esc

In a nutshell, the Electronic Speed Controller is a silicon chip that takes a low voltage command signal and amplifies and translates it into the correct voltage and high current  to control the motor.  Each motor has one.   Theoretically, an ESC could fail but the motor can still be monitored for rotation speed, therefore leading to the conclusion the controller failed, and the motor was not seized or obstructed until it hit a tree.

Is there any way to prevent ESC failure from happening in the future with my New Phantom 4 Pro Obsidian?  What should I be on the lookout for. Can DJI provide Analysis on this forum for drone checkups thru DJI Assistant?
2018-1-13
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