RE: Confusing crash probably Futaba RX related
If it was me I would move the ends away from the servos, they are brushed servos if I am not mistaken.
The brushes if worn may cause excessive sparking under load which may cause RF noise. Random RF noise that close could swamp out the real signal resulting in failsafe, then the servo motors stop moving, the RF noise goes away, signal is now good, regain control. I am not saying this is the problem, just something I would change.
Need more info and debug-testing.
I have tested my 6014's to 3.2v with no problems, fail safe was not set when testing.
All done using calibrated equipment.
There is a reg inside the RX that regulates the input voltage to 3.0v for the RX logic.
Takes quite a dip from 5v to lock every thing out.