Hoping someone can assist.  I have a Mini pro 3 and haven't had any issues until today.  When I went to launch it, it took a nose dive immediately into the ground and flipped.   I replaced all the props after the crash.  Then calibrated the compass and IMU like 4 times.   I’m not fully taking off when I’m testing it now but I can tell the nose is pushing forward when I give it some power.  

Was this a hand launch? If so read https://forum.dji.com/forum.php? ... 9&page=1#pid3429667, in particular post 10.
If it wasn't a hand launch then have you replaced any of the front props prior to the crash flight ?


If you want further assistance go to
https://www.phantomhelp.com/LogViewer/Upload/
Read the instructions there and follow any relevant links.
Retrieve the .txt flight log and upload it to the webpage.
Post the resulting URL here.
You might also want to retrieve the DAT flight log which should be in the folder named MCDatFlightRecord and will have a similar date and time stamp to the .txt flightlog. Upload that DAT to a file hosting website make the page public and post its URL here
Alternatively you might be able to upload both flight logs as zips to here as attachments.

ok, but that link doesn't seem relevant.  Maybe I should not have said "launch"?  it was a normal takeoff from a flat surface.  

jfk0027 Posted at 10-1 13:00
ok, but that link doesn't seam relevant.  Maybe I should not have said "launch"?  it was a normal takeoff from a flat surface.

Ok, I have edited the my previous post and asked a question regarding the props.

Replaced all props after the crash

jfk0027 Posted at 10-1 13:06
Replaced all props after the crash

Yes I read that, I am asking about prior to the CRASH flight. Ooops I didn't sorry, TYPO, now corrected.

no, nothing changed prior to crash.

jfk0027 Posted at 10-1 13:11
no, nothing changed prior to crash.

Hmmm in that case I'd suggest you follow the instructions for at least the .txt flight log.
The DAT may or may not be readable.

If the drone still push forward, have you checked if any of the settings in the radio have perhaps changed?

Are the left and right props in the correct location?

Burt37 Posted at 10-1 13:29
If the drone still push forward, have you checked if any of the settings in the radio have perhaps changed?

Are the left and right props in the correct location?

I am puzzled, what change of settings do you think could cause this ?

Sean-bumble-bee Posted at 10-1 13:32
I am puzzled, what change of settings do you think could cause this ?

I don't even know which radio he is using, but I was thinking along the line of the setting for the different fly modes,or when you update the firmware and the radio goes back to factory default...

Just a suggestion...

After an accident, you should always check the motors, they should all rotate freely. Can you hover motionless? After a few minutes of hovering, you should check the temperature of the motors, are there any that are getting hotter than others?

Burt37 Posted at 10-1 13:36
I don't even know which radio he is using, but I was thinking along the line of the setting for the different fly modes,or when you update the firmware and the radio goes back to factory default...

Just a suggestion...

OK .........

motors seem fine and props are install correctly.  I'm using the RC controller.  I'm updating firmware because I see a message about some sort of login on error on the controller.  never needed to login before

Sean-bumble-bee Posted at 10-1 13:12
Hmmm in that case I'd suggest you follow the instructions for at least the .txt flight log.
The DAT may or may not be readable.

https://www.phantomhelp.com/LogViewer/202410017I6UJ9TG2T0KDE30OQNYMTYV9NADV7SP

jfk0027 Posted at 10-1 15:43
https://www.phantomhelp.com/LogViewer/202410017I6UJ9TG2T0KDE30OQNYMTYV9NADV7SP

At the moment I see three odd things.
1) up until 2 seconds the drone has a pitch of -5.x degrees, which I think is nose down. It gets more or less level by 2.8 seconds, is that correct ?
2) you didn't give the drone full throttle during what may have been the launch ( that might have been a mistake )
3) the height, as reported by the barometer, went to negative 3ft, meaning the drone thinks it was below the height where the motors started, is that possible ?

jfk0027 Posted at 10-1 13:00
ok, but that link doesn't seem relevant.  Maybe I should not have said "launch"?  it was a normal takeoff from a flat surface.

I see people guessing what your problem is but all they have to go with is your brief description.
But I don't see any of the recorded flight data that would show what actually happened.
It's important to know what actually happened to be able to solve the problem.

Go to: https://www.phantomhelp.com/LogViewer/Upload/
... where you'll find instructions.
Follow those and you will get a summary report.
You can post a link for the report here.
Or just post the .txt file.

If your controller has a built-in screen, you'll find the file at:
Android\data\dji.go.v5\files\FlightRecord

Labroides Posted at 10-1 17:43
I see people guessing what your problem is but all they have to go with is your brief description.
But I don't see any of the recorded flight data that would show what actually happened.
It's important to know what actually happened to be able to solve the problem.

Look at post 15, the OP provided the link to the log on phantom help, it works and I have both the CSV and txt downloaded.

You were very gentle on the sticks when you launched and only reached full throttle at 2.8 seconds.
The data shows the crash at 3.0 secs.
The only indication that the drone had lifted was VPS indicating 0.3 ft at 2.8 secs.
At 3.0 secs, the data shows the drone kicking backwards (nose-up/tail down) 26° without any related joystick input .

How close to the ground was the drone when things turned bad?
I'm a little puzzled at the way the drone bumped around so much if it was just a few inches above ground.
What was the surface you launched from?
Flat and smooth ... stony .. grass and weeds?
Was there anything that a prop could have contacted while hovering?

I was taking off from an elevated table on my porch.  So when it took off and did its nose dive it went off the porch (probably where the negative 3 ft is being seen).  luckily hit the bushes before hitting the ground.  I have taken off several time from that same spot without issue.  

jfk0027 Posted at 10-2 09:26
I was taking off from an elevated table on my porch.  So when it took off and did its nose dive it went off the porch (probably where the negative 3 ft is being seen).  luckily hit the bushes before hitting the ground.  I have taken off several time from that same spot without issue.

Is the table top tilted ?
Do you have the DAT flight log ? If so can you post it as suggested in post number 2 ?

Sean-bumble-bee Posted at 10-2 09:47
Is the table top tilted ?
Do you have the DAT flight log ? If so can you post it as suggested in post number 2 ?

Now I am on computer I can post the following, produced using CsvView

https://datfile.net/CsvView/downloads.html

jfk0027 Posted at 10-2 09:26
I was taking off from an elevated table on my porch.  So when it took off and did its nose dive it went off the porch (probably where the negative 3 ft is being seen).  luckily hit the bushes before hitting the ground.  I have taken off several time from that same spot without issue.

I have taken off several time from that same spot without issue.  
Have you always been so gentle on the throttle when launching?
You should get the drone up a couple of metres, well away from obstacles, rather than just a couple of inches.

Labroides Posted at 10-2 15:28
I have taken off several time from that same spot without issue.  
Have you always been so gentle on the throttle when launching?
You should get the drone up a couple of metres, well away from obstacles, rather than just a couple of inches.

not sure.  

DAT file:  https://drive.google.com/file/d/1IfExvkYYTEz6WMmy6nVIOP_ZjwB-l5UK/view?usp=sharing

jfk0027 Posted at 10-4 06:55
not sure.  

DAT file:  https://drive.google.com/file/d/1IfExvkYYTEz6WMmy6nVIOP_ZjwB-l5UK/view?usp=sharing

Great,  I will have a look later when I get on to a computer

jfk0027 Posted at 10-4 06:55
not sure.  

DAT file:  https://drive.google.com/file/d/1IfExvkYYTEz6WMmy6nVIOP_ZjwB-l5UK/view?usp=sharing

The DAT is readable, therefore I suggest you post the story including mention of the table top launch site and URLs over on the MavicPilots forum in https://mavicpilots.com/forums/crash-flyaway-assistance.85/
The DAT also indicates that on the tablet top the drone was NOT LEVEL in pitch, -6.64deg.

I do not know if that is normal for the Mini 3 nor if it is significant
Attached are plots of the motor speeds and pitch and roll angles recorded in the DAT, note that the DAT akso covers the period before the motors were started.

jfk0027 Posted at 10-4 06:55
not sure.  

DAT file:  https://drive.google.com/file/d/1IfExvkYYTEz6WMmy6nVIOP_ZjwB-l5UK/view?usp=sharing

You don't remember if you usually just lift the drone an inch or two rather than sending it  feet off the ground?

Sean-bumble-bee Posted at 10-4 11:17
The DAT is readable, therefore I suggest you post the story including mention of the table top launch site and URLs over on the MavicPilots forum in https://mavicpilots.com/forums/crash-flyaway-assistance.85/
The DAT also indicates that on the tablet top the drone was NOT LEVEL in pitch, -6.64deg.

well I recalibrated again (IMU, Compass).  This time when I did the RC calibration (but did NOT do the RC compass calibration).   

So after that, I tested it and it didn't seem to push forward much (when providing ascent input).  So i got the guts up to take off and it was fine.  I really appreciate all the help.  

Labroides Posted at 10-4 15:06
You don't remember if you usually just lift the drone an inch or two rather than sending it  feet off the ground?

depends if I have an overhead environment (like the porch I was taking off from this time).  

jfk0027 Posted at 10-5 07:24
well I recalibrated again (IMU, Compass).  This time when I did the RC calibration (but did NOT do the RC compass calibration).   

So after that, I tested it and it didn't seem to push forward much (when providing ascent input).  So i got the guts up to take off and it was fine.  I really appreciate all the help.

Questions.
1) can you confirm that the table is absolutely level?
2) If so then I suggest that you set the drone on the table and start the drone's motors using the CSC.
DO NOT ATTEMPT to take off, rather let the motors idle for 30 to 60 seconds then stop the motors and switch the drone off.
Upload the .txt flight log for that motor run to phantomhelp and post the URL here, so that the drone's pitch can be checked.
As I have already mentioned, the .txt and I believe the .DAT that you have already provided indicate that the drone is tilted in pitch.
I do not know if this is normal for a Mini 3.

If the new .txt shows 0 or near 0 pitch and teh table WAS level then it might be that erroneous indicated tilt was the cause of the crash but that is just speculation on my part.
You need the likes of JJB*, Budwalker or the log readers over on mavic pilots to have a look at your logs, they are much better at log reading than I am.

One other suggestion, in subsequent flights do not gradually increase the throttle in order to launch the drone, go straight from neutral throttle to full throttle, get the drone safely in the air then, if wanted, ease off the throttle. BUT DONT slam the throttle fully open, you might damage the joystick's gimbal.



When ground launching my drone I guess I go from neutral throttle to full throttle in less than 1/5th of a second.
It's a dangerous zone in which to be hesitant.

Burt37 Posted at 10-1 13:29
If the drone still push forward, have you checked if any of the settings in the radio have perhaps changed?

Are the left and right props in the correct location?

That's what I was going to say, I inadvertantly put one set of props on the wrong way once with my old drone and they behaved just like he describes.

Cheers

Burt37 Posted at 10-1 13:29
If the drone still push forward, have you checked if any of the settings in the radio have perhaps changed?

Are the left and right props in the correct location?

Are the left and right props in the correct location?
In post 7 the OP indicates that the props had not been changed prior to the crash and I assume it flew perfectly well in flights prior to the crash.

However the point of this post is to ask if you would look at
https://forum.dji.com/forum.php? ... 8&page=1#pid3435030
and contribute a suitable log, via PM of a Phantom help URL if you want to, I think you have a Mini 4 Pro.
If you do contribute I would ask that you first verify, with the likes of a spirit level,  that the surface IS LEVEL.
Any log sent via PM will be kept private.

I started that thread because of the tilt evident, whilst the drone was  on the table top, in the logs of this thread and the failure of the OP  to answer my question about whether the table top is level and whether  there is a change following their calibration of the IMU.

Blackbuckone Posted at 10-6 05:31
That's what I was going to say, I inadvertantly put one set of props on the wrong way once with my old drone and they behaved just like he describes.

Cheers

see post 7 and earlier posts.
Additionally, props on the wrong motor tend to pin the affected motors to the floor and the drone doesn't take off it tend to flip.
https://forum.dji.com/forum.php?mod=viewthread&tid=217527
demonstrates the symptons.

With regards to 'wrong props.'

I don't know if the mini 3 & 4 have the capability but, with the FPV, I once made a mistake and put the wrong prop on one or probably two motors.
When I gave the drone throttle there was an increase in RPM but the drone almost immediately shut down all the motors and the goggles gave a warning that props were incorrectly installed.
A Duuuh, Homer moment.
I was somwhat disappointed that it was actually possible to do that with the FPV, the Mavic 2 prevents it, so, rhetorical question, why doesn't a later drone?

It might be an interesting experiment with a mini 3/4 and partial throttle to see if the drones detect the mistake and shut down the motor but I would NOT do it on a table top where there is a confined flipping area ......... but I like semi crazy experiments lol.


But if the FPV includes the programming to detect such a mistake I see no reason that it couldn't be included it firmware updates for the mini 3/4.

Sean-bumble-bee Posted at 10-5 08:30
Questions.
1) can you confirm that the table is absolutely level?
2) If so then I suggest that you set the drone on the table and start the drone's motors using the CSC.

Hi Sean,

Thanks for my name in your post.

Log is really short, only very short UP stick...bc i think OP saw drone already got nose down and roll to one side.
This only happens with blades at incorrect motors.
If you put your drone on a slope, at take off it will level horizontal direct after take-off.

cheers
JJB

JJB* Posted at 10-6 07:07
Hi Sean,

Thanks for my name in your post.

You are welcome.

But if you note, early on in the thread I asked the OP, by implication, if there was a chance that the props were on the wrong motors.
His post 7 reply suggests that the props had NOT been changed prior to the crash and I assume it flew perfectly well during the flights prior to the crash.

My concern is the tilt/pitch-angle showing, whilst the drone was on the table top, 5.x deg in the .txt flight log and 6.y deg in the DAT.
I do not know if this tilt stems from the table top NOT being level or there being a sensor/IMU error or offset.
I think you have participated in a few DAT discussuions so perhaps you can make more of the .txt and DAT than I can.

I also wonder if you would care to contribute to the thread
https://forum.dji.com/forum.php?mod=viewthread&tid=319979&page=1#pid3435065

If you do contribute I would ask that you first verify, with the likes of a spirit level,  that the surface IS LEVEL.
Any log sent via PM will be kept private.

I started that thread because of the tilt evident, whilst the drone was on the table top, in the logs of this thread and the failure of the OP to answer my question about whether the table top WAS/IS level and whether there is a change in the indicated tilt following their calibration of the IMU.

Sean-bumble-bee Posted at 10-5 08:30
Questions.
1) can you confirm that the table is absolutely level?
2) If so then I suggest that you set the drone on the table and start the drone's motors using the CSC.

Table top - perfectly level side to side.  but there is a pitch down forward.  not sure how many degrees  

JJB* Posted at 10-6 07:07
Hi Sean,

Thanks for my name in your post.

props were on the correct motors.

Sean-bumble-bee Posted at 10-6 07:29
You are welcome.

But if you note, early on in the thread I asked the OP, by implication, if there was a chance that the props were on the wrong motors.

Hi,

My AIR3 on flat table shows + 6.3 pitch up, roll flat values.
Normal values as the front legs are too long  ;-)  

But will put my drones on 2 spirit levels to get really correct values.

cheers
JJB

jfk0027 Posted at 10-6 11:23
props were on the correct motors.

oke, did you had another try to take-off?  after calibration of the IMU.
Nice to make a video to show this forum

cheers
JJB