Stability Issues with APM2.6 Build

Hi All,

We've taken a 3DR Quad and changed it a bit to try and get more payload and more flight time. Here are the current specs:

Motors: T-Motor MT3520-11 400KV

ESCs: Phoenix Edge Lite 50 Amp

Props: APC 13 x 4.7

Battery: Zippy 5S 5000mAH

RC: Spektrum DX8

APM Model: 2.6 with 3.0.1 Firmware. The APM back rail is getting power from motor 4 ESC and the front rail is getting power from motor 1 ESC.



The APM has been mounted on some foam to reduce vibrations. All wiring has been checked, double checked and all calibrations that could be done have been done as well (compass, radio, accelerometer) but we cannot get the thing to fly without doing flips! Here is a video of the issue which shows two of the flights.




I've looked around on the forums and Google and have seen other people with similar problems but theirs were the result of incorrect motor wiring. So my question is... does anyone know what is going on here and how I can fix this?


Thank you!


2013-10-06 18-04 12.log.gpx

2013-10-06 18-04 12.log

You need to be a member of diydrones to add comments!

Join diydrones

Email me when people reply –


  • I have seen this problem two times, once it was due to to much vibrations, second time was due to cold solder joint. Do you use bullet connectors between esc and motors or esc and battery?

This reply was deleted.


Neville Rodrigues liked Neville Rodrigues's profile
Jun 30
Santiago Perez liked Santiago Perez's profile
Jun 21