Please help my P4 crashed

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My P4 went up to 35' ft then dropped like a rock. I hope I load the log correctly. Can anyone explain please.
 

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For everyone's convenience, here's the result of putting it through Phantomhelp's log viewer.


Seems to have been a GPS problem. You can read a lot of comments about this error with this search (magnifying glass, top right). Some say the error message is nothing to worry about but quite a few people have lost control simultaneous to seeing it.

 
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Meta4

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Seems to have been a GPS problem.
You can read a lot of comments about this error with this search (magnifying glass, top right). Some say the error message is nothing to worry about but quite a few people have lost control simultaneous to seeing it.
It was not a GPS problem.
Even if GPS is lost completely that has no effect on the drone's ability to hold altitude.
The GPS Position No Match message is a common meaningless false alarm and had nothing to do with the incident.
My P4 went up to 35' ft then dropped like a rock. I hope I load the log correctly. Can anyone explain please.
There is something unusual in your flight data.
Your barometric sensor (the main altitude sensing device) is showing no data at all.
The VPS (downward facing sensors for close range height measurement) shows the drone climbed to 35 ft and then came down.
The motors stayed on and there was no spinning which would indicate a failure of a motor or ESC.

It appears that the failure of the barometric sensor prevented the drone from holding altitude.
You launched and gave a little left stick down which started the descent, but without altitude holding, the drone kept descending.
You made no corrective moves with the left stick which might have arrested the descent.
 

ianzone

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Much damage,,me had battery fail and could only watch,if the house was not in the way I would have tryed to catch it,,hey also were you using new set up metion in range extenders,,just curious or original remote
 
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ianzone

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I'm sure [?......i just notice on stick inputs it only show stick start and no input as its going g up,,,,this is the users problem,,we found out why it came down but why did it go up in the first place,,,,,,USER=6114]@Meta4[/USER] hit this on the head,,yellow arrow I draw show the 2nd stick input down,,unsure why no GPS match,,,would letting home point set prevent this or ?why would it change to atti mode and drift ? It should have regained sats dont you think ?,something at play mayby to do this or lead in the clouds to block satellites or got solar flared ? These questions bug me,,,also why did it continue to drop even when stick let go it should drift with wind not continue down,another curious question,,,,also a question for the OP,,,did you give any stick input to go up,it shows a slight input but mayby the remote wasn't calibrated at 100% on the stick input,,you should check your rc ,,your left stick might not be centered which will make it rev past idle speed
Screenshot_20200915-173404_Chrome.jpg
 
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I'm sure [?......i just notice on stick inputs it only show stick start and no input as its going g up,,,,this is the users problem,,we found out why it came down but why did it go up in the first place,
... also why did it continue to drop even when stick let go it should drift with wind not continue down,another curious question
His left stick inputs were:
Left stick up​
0:03.2 - 0:05.2​
Left stick down​
0:00.4 - 0:00.5​
0:06.1 - 0:06.3​
0:06.7 - 0:07.1​
Without any sensor input from the barometer, his drone was acting like "vertical atti mode".
With a little left stick up, the drone would go up but when the sticks were centred, it would continue going upwards until there was some left stick down.
But with left stick down, the drone would continue going down even when the stick was centred.

Perhaps it might have been recovered with some gentle up/down moves to get control of the altitude, but any pilot would have been confused to have their drone act this way and there wasn't much time to work it out.
unsure why no GPS match,,,would letting home point set prevent this or ?why would it change to atti mode and drift ? It should have regained sats dont you think ?,something at play mayby to do this or lead in the clouds to block satellites or got solar flared ? These questions bug me
,also a question for the OP,,,did you give any stick input to go up,it shows a slight input but maybe the remote wasn't calibrated at 100% on the stick input,,you should check your rc ,,your left stick might not be centered which will make it rev past idle speed
Looking closer at the data, I see there was an issue with GPS and perhaps the Position NoMatch message meant something after all (but 99% of the time you see this it's meaningless).
Although his GPS was receiving up to 17 sats for the flight, the Flight Controller rated the GPS health as 0/5 for the whole time.
No home point was recorded but his position was being recorded every 1/10th of a second even though the data was not used for navigation.
There was nothing blocking sats so no need to consider left field ideas about lead in clouds (? never heard that one before) or solar flares (which have never had any measurable effect on drones).
It probably didn't drift much on the breeze because there wasn't much breeze.

But none of that had any effect on the real problem which was the Phantom's inability to hold altitude.
There is no hint of any issue with his controller or its calibration either.

Short Version .. there was a serious issue with the IMU (including barometer) that prevented altitude data from showing and caused the rejection of GPS data.
 
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New setup
I sent it up to 35' and wanted to bring it back to around 20' will it just dropped like a rock, and before I could react, it hit my deck. Camera and g8mble ate ok, I am now getting an IMU and GPS errors. Landing gear took a bad beating.
 

ianzone

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I sent it up to 35' and wanted to bring it back to around 20' will it just dropped like a rock, and before I could react, it hit my deck. Camera and g8mble ate ok, I am now getting an IMU and GPS errors. Landing gear took a bad beating.
Oh bummer,you probably have to open shell up,some boards have ribbon cables and boards on rubbers that only stretch so far ,I would get a ribbon set as back up for these occasions, most parts cheap so that's bonus,mine tore esc ribbon cables on impact and some others ,,
 
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Left stick up might prevent descending and might not. We don't know that.
But he had less than one second to react so that was almost impossible.
Luckily nobody was hurt.
 
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I'm sure [?......i just notice on stick inputs it only show stick start and no input as its going g up,,,,this is the users problem,,we found out why it came down but why did it go up in the first place,,,,,,USER=6114]@Meta4[/USER] hit this on the head,,yellow arrow I draw show the 2nd stick input down,,unsure why no GPS match,,,would letting home point set prevent this or ?why would it change to atti mode and drift ? It should have regained sats dont you think ?,something at play mayby to do this or lead in the clouds to block satellites or got solar flared ? These questions bug me,,,also why did it continue to drop even when stick let go it should drift with wind not continue down,another curious question,,,,also a question for the OP,,,did you give any stick input to go up,it shows a slight input but mayby the remote wasn't calibrated at 100% on the stick input,,you should check your rc ,,your left stick might not be centered which will make it rev past idle speed View attachment 120015
I did nothing, it suddenly launched straight up. All I did was push down 1/2 way twice to try and arrest the accent. 1.8 seconds later it crashed onto my deck. I calibrate my controller a few times a week. And had done it that morning. I took a 2 mile flight, landed to change batteries, and it went demonic
 
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I did say b3fire that I sent it up to 35', I misspoke. The **** thing had a mind of it's own
 

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I calibrate my controller a few times a week.
That's an unusual thing to do.
Have you been having problems with the controller?
I did nothing, it suddenly launched straight up. All I did was push down 1/2 way twice to try and arrest the accent. 1.8 seconds later it crashed onto my deck.
I took a 2 mile flight, landed to change batteries, and it went demonic
The yellow highlighted numbers from your data indicate the left joystick being pushed up.
Blue = non-functioning barometer data
Green = VPS altitude increasing after left stick input.
i-xbhssnw-L.jpg
 
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ianzone

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I delete post cause seems my English version cant be understood,,we know why it went up and down but why did this error occur,faulty product,under warranty still,,
 
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That's an unusual thing to do.
Have you been having problems with the controller?

The yellow highlighted numbers from your data indicate the left joystick being pushed up.
Blue = non-functioning barometer data
Green = VPS altitude increasing after left stick input.
i-xbhssnw-L.jpg
The only thing I can think of, is the super-patch 2.0 was at fault.
 

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