Spirit System

Hello,

that is very sad.

I guess that some servo or BEC did not survived the load which is very strange. For sure this would happen sooner or later without BEC test too.
Only in case of too high frequency this could happen. But usually with an analogue servos or old Align/Savox servos that are not designed to be used at FBL helicopters.

But it is very strange that everything was damaged. The most probably is I guess BEC failure which then sent too high voltage to the electronics. Just Spirit unit can survive quite high voltages.

Can you write what ESC and servos were used?

I am afraid but these servos are very insufficient for a FBL units. The performance would be very poor in any case.
They should be equipped with coreless motor. For example at least TGY-306G for swashplate.