Quadcopter flips and falls out of the sky


Junior Member
The title pretty much sums it up..

I have a Flip FPV Pro quadcopter frame. (which is now broken..)
4 iPower motors
4 ESC's from ready to fly quads with SimonK firmware
Flip 1.5 multiwii flight controller from ready to fly quads

I have calibrated my ESC's and done all the necessary setup to fly.

Whenever I go out and fly, everything works fine for 5-10 minutes. However, at some random point during the flight, the quadcopter will flip itself upside down and fall straight out of the sky. I try to give it throttle to recover, but nothing happens and I crash. It is pretty frustrating because some flights the quadcopter works perfectly and other flights it will fly for a few minutes, flip itself and fall to the ground.

Any help/advice would be greatly appreciated!



Faster than a speeding face plant!
Does the copter always flip and fall in the same direction? This may indicate that a motor or ESC is shutting down and would tell us which one.

Do you have multiple batteries? If so, is it always on the same battery when it falls? Do you use a voltage monitor on the copter? How much voltage do you have left in the battery after a crash?

Does the lipo or any of the ESCs or motors feel hot after a flip and dump?

What are the mAh and C rating of your lipo and the kv of your motors?


Junior Member
It could be desync. I've had issues with SimonK ESC's desynchronizing with aggressive throttle changes and/or high PIDs, they take a while to recover usually. If you're flying slowly with low PIDs and it's still happening, this is probably not it though.
I second the motor/ESC thought, I had the same problem on my first quad when I tried to use HK Red brick ESC's. I assumed the esc was overheating, I have since switched to Turnigy Plush series with no further issues.