Standard 3. On take off it rose to 4 feet and started doing small circles which kept getting wider and wider. Shut it down. Recalibrated compass. Tried again. This time it did the same thing only I lost total control and could not land. Grabbed it out of the air, reached up and pulled the battery.
Next day recalibrated compass and IMU. Launched and it rose to 4 feet, started circling as before, Tried to shut down and it took off across the yard and crashed.
Recalibeated everything again. This time I launched it while gently hanging on to it. It rose to 4 feet and was not flying level then suddenly one motor quit. I suspect this is what happened when it flew away.
Any thoughts?
Thanks in advance.
Ron

Was a motor hotter than the others?

Where is this happening?
What you describe is what happens if you fly 4 ft above a steel roof or a pile of reinforcing steel on a construction site.
Calibrating the compass isn't the solution.
Moving away from what's upsetting the compass is.

Thanks for the replys.

No, the motor wasn't hot. That's the first thing I checked. It was cool and spun freely.
Blades were correctly installed.
We are in the country and away from buildings and it's flown here a few times without incident.
What really worries me is that I lost all control when it flew away. Couldn't land, shut it off, steer, nothing. This is what it did the time I had to reach up and disconnect the battery because I had no control. (Incidentally, that's scary reaching up between the blades and trying to slide the battery out enough to kill it. Batteries are hard to remove.)
We will be going to our river property in a couple days and I'll try it again.
Although I've had this drone for a couple years it has only flown about a dozen times.

Hello and good day Ron. I am sorry to know about what happened. Did you check if the propellers if they are properly installed in correct motors? If there's a damage on your drone, I would recommend sending the drone into our repair facility for further evaluation. Please contact DJI support at https://www.dji.com/support for further help on this issue. Thank you.

It rose to 4 feet and was not flying level then suddenly one motor quit. I suspect this is what happened when it flew away.
It can't fly away on 3 motors.
If one motor stops, the drone spirals into the ground.

Your description is confusing but the recorded flight data probably won't be.
Go to http://www.phantomhelp.com/LogViewer/Upload/
Follow the instructions there to upload your flight record from your phone or tablet.
Come back and post a link to the report it gives you.

This should be an interesting read.



RedHotPoker

Hi,
I looked for the flight records. There is a record of a flight about a month before the problems happened. It shows everything ok except for the last few entries shows a "Compass Error". There are NO flight records for when it took off on it's own or for when I was hanging on to it.

Here is a link to the last recorded record. https://www.phantomhelp.com/LogViewer/S1O6PUWROCHVOKGI995A/
Could the issue be with the controller and not the drone?
Incidentally, I was flying around my house checking for roof damage from raccoons.

Boomologist Posted at 1-7 10:15
Here is a link to the last recorded record. https://www.phantomhelp.com/LogViewer/S1O6PUWROCHVOKGI995A/
Could the issue be with the controller and not the drone?
Incidentally, I was flying around my house checking for roof damage from raccoons.

Nothing unusual about that flight until the very last moment, when you get a compass error.  When a compass error occurs, the aircraft will automatically switch to ATTI mode, and unless you are aware of that, and know how to fly in ATTI mode, it might seem like it has lost control. What surface are you starting the aircraft on, and flying from?

Boomologist Posted at 1-7 10:15
Here is a link to the last recorded record. https://www.phantomhelp.com/LogViewer/S1O6PUWROCHVOKGI995A/
Could the issue be with the controller and not the drone?
Incidentally, I was flying around my house checking for roof damage from raccoons.

The compass error in that flight only shows when you have landed.
The most likely explanation for that is not a problem with your compass at all, but a perfectly working compass warning you that there's something magnetic close by.
Where did you land?  On steel or reinforced concrete perhaps?

I was flying around my house checking for roof damage from raccoons.
And this is when you had the issue you are asking about?
Read post #3 again and see if this fits.

The surface it was taking off and landing on was dirt/gravel driveway that did have a little snow on it. I've flown from this spot and around the roof before few times without issue. The house is wood with 3 tab roof. There are a couple vehicles in the driveway that were about 35 feet from the drone.
I have located another controller and will be trying it later in the week.

Boomologist Posted at 1-7 15:46
The surface it was taking off and landing on was dirt/gravel driveway that did have a little snow on it. I've flown from this spot and around the roof before few times without issue. The house is wood with 3 tab roof. There are a couple vehicles in the driveway that were about 35 feet from the drone.
I have located another controller and will be trying it later in the week.

Lets try again.
Did you get the spiraling when you were flying above the roof?
Is the roof made of steel?
How high above the roof was the drone?

Your controller is unlikely to have been involved.
The Phantom slowly spinning is because your compass was affected by the magnetic field of something close by.

Boomologist Posted at 1-7 10:15
Here is a link to the last recorded record. https://www.phantomhelp.com/LogViewer/S1O6PUWROCHVOKGI995A/
Could the issue be with the controller and not the drone?
Incidentally, I was flying around my house checking for roof damage from raccoons.

Is that flight record from the day that the issue you are posting about occurred?

There is no flight record from the day it first did this and no record after that which I find strange. It's like the controller lost connection with drone.
The drone started the circling thing as soon as it got 4 feet off the ground.
Roof is wood with asphalt 3 tab shingles.

Well, made it to our river property. Tied the drone to a chunk of 6x6 with 10 feet of shroud line. Re-did the IMU. Took off and rose to about 4 feet. Didn't do the circling thing but did drift slightly and return intermittently (not over 3 feet). I'm thinking this could be from backwash from the props. Took it up about 7 feet and while it drifted a little it wasn't too bad. After a few minutes I would hear a short "squeal" sound. Kind of like a dry bearing. Short and intermittent. Controls seemed good. That one prop did not slow and quit as it did before.
I'm thinking that prop may have got some snow/water in it before and made it weak before stalling it out. Once dried out it works as it should.
Questions:
Do these motors have bearings or bushings?
Is it ok to put a drop of WD40 on the motor shafts?
Thanks in advance,
Ron

I have read in posts that these are "shielded" bearings which is to say it is possible to lube the bearings if you use the correct oil and if you use a very small amount - much less than a drop.  You would apply this miniscule amount of oil to the obvious place near the shaft with an appropriate tool (such as maybe a tooth pick) and allow the oil to "wick" its way into the bearings.  However, this is not a recommended procedure and usually unnecessary.  I personally have never lubed a motor or had a motor (or ESC for that matter) fail during flight.  I have at times heard a minor squeaking sound as I hover before a flight, but I fly anyway and nothing ever happens.  If the motor isn't overheated, I would not worry about it.  I would not attempt to lube it without an overheating problem because it could potentially attract dirt and create a motor problem whereas before you had no motor problem.  MHO.

I think it's likely Labroides was right above and you had metal or iron or something (car keys? cell phone?) interfering with the compass earlier.  I also think it's possible your flight controller is bad.   In other words, you could have had two problems.

Are you sure you're doing the IMU calibration correctly?  That is, are you making sure the AC motors are all perfectly level in all directions before you start the IMU calibration?  

When you hover it at eye level, are all four motors perfectly level with each other?

If the answers are yes and no, you probably have a bad FC.  

If the answers are yes and not sure, you probably have a bad FC.  

Good luck

Boomologist Posted at 1-19 13:57
Well, made it to our river property. Tied the drone to a chunk of 6x6 with 10 feet of shroud line. Re-did the IMU. Took off and rose to about 4 feet. Didn't do the circling thing but did drift slightly and return intermittently (not over 3 feet). I'm thinking this could be from backwash from the props. Took it up about 7 feet and while it drifted a little it wasn't too bad. After a few minutes I would hear a short "squeal" sound. Kind of like a dry bearing. Short and intermittent. Controls seemed good. That one prop did not slow and quit as it did before.
I'm thinking that prop may have got some snow/water in it before and made it weak before stalling it out. Once dried out it works as it should.
Questions:

Any luck yet finding your flight record?  
See post #7 for instructions
It's hard to believe that there is none.

Just found one flight record. https://www.phantomhelp.com/LogViewer/WJMYTCUKRVFOS2EADR22/
This is from the time I hung on to it. It was leaning then one motor quit. Seems a few things were out of balance. The heavy draw on that cell could indicate a stuck motor.
For some reason the flight record from today isn't there.

I have flown four times yesterday with the aircraft tied to shroud line in case it decided to fly away (added 30 feet to the 10). It did ok except I did see one message saying it had regained connection with the controller. Either it got water/snow inside that messed with the circuits or there was some radio frequency interference that caused it to fly away that day. I'll try it again when we return home tomorrow.

I've done everything to locate the record from when it flew away. It's just not there. I did not have any control over the aircraft during that flight although I had enough control to get it off the ground.  I won't trust it for awhile so flights will be close in and I do have a small GPS tracker that I can attach to it.
Thanks for all your help and advice.

Light bulb just came on!
If there was a little water from snow in the motor pod is it possible that as the blades pushed air across the motor it created ice? Similar to what happens when conditions are right with a carburetor and carburetor ice forms on the throttle plate and after it dries out it goes back to normal operation?