P4 Hard Roll on Take-off

Phantom 4
1

A friend gave me a Phantom 4 after he had an incident with it. Upon inspection I found one of the motors overheated (melted the mount) and cracks in the skids and upper and lower shells. I replaced all of these items, calibrated the compass and IMU, and went for a test flight. Upon commanding take-off it ascends about 3 inches then rolls hard right contacting the ground. I checked propellers and ensured the motors were spinning in the correct direction. I tried taking off several times, all with the same results. I attached the link to the log below. I did not see anything related to how the aircraft reacted. Any help would be appreciated.

https://www.phantomhelp.com/logviewer/C9J082RL7KDQ7RCCSH04

Mark W

2

You may want to re-check your wiring. Also the .dat file for this would help. According to the event log, this is why:

27.6,MOTOR IS IDLING (LOST OR MISSING PROPELLER).

3

Here is a link to the DAT file.
https://drive.google.com/file/d/1WsJlFcnkp6I1J_58473lp1ypB1lPhzr3/view?usp=sharing

4

Here is a link to the DAT file

https://drive.google.com/file/d/1WsJlFcnkp6I1J_58473lp1ypB1lPhzr3/view?usp=sharing

5

First question. During your replacement of the motors, did you use splices anywhere between the motor and ESC? If so, that could be the issue. The wires need to be directly solder replaced. It could be the ESC itself, assuming from your statement of “melting the mount” it appears to be the right rear.

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6

Thanks for the analysis. Yes, I did splice the wires but I soldered and ohmed them out afterwards. I was trained in high reliability soldering in the Air Force so I am pretty confident in my soldering job. But I have seen enough cold solder problems that I am never 100%. I will try the ESC first. If that is not it I will get new motors and get rid of the solder joints.

I think I found the DAT file from when he had the problem. I didn’t realize he had the proplem in 2019and just left it in the case all this time. I’ll upload it and send a link when I get back to my laptop if you want to compare.

7

Hi @radarman141, I have more or less the same issue. They has changed two motors I can see the thread are new. Everything runs fine still take off.

It will not hover but break out, every time the side where the shell is cracked.

I have also flyxxx.dat files but I don’t know how to open this file`s. I think motors and ESC can be the problem.

I hope you find the problem,let us know and hear it.

Best,