Hi All,
      I am facing flipping issue while taking off the quadcopter. I have calibrated the ESCs, Set the layout as Quadcopter X. Also tried various PI settings but still I am facing the  same issue. Can anyone let me know how to solve it?  Below are quad specs

Frame = F450
Motor = A2212 1400KV
Props Used = 8x4.5 , 10x4.5(Face same issue in both sizes)
Esc Rating = 30A

Please refer below link for the video.
https://drive.google.com/file/d/18U53p5Lt-kgvyOd_bNsuWkZ1PH54APcQ/view?usp=drivesdk

I watched the video. Couldn't exactly judge whether the motors are spinning in the right direction. If you confirm there is no issues like that, then the problem could be any of the 2 things.
1. ESC problem (generally which comes after a hard crash)
Any crashes recently? Whether the quad struck anywhere and you applied throttle continuously for few time?

2. Motors
In your case, i guess just 1 motor should have the problem (if the problem is not esc related)

I suggest you to do this first 


If this didn't work out, you should carry the other tests.

And I forget to ask. The video you posted, you are giving atleast half throttle. Right?

I don't see this as flipping issue. Rather if you watch closely, the quad is trying to take off.  But only one leg is not willing to fly and trying to stay its best on the ground. when you apply more throttle, the quad goes sideways and then it is automatically gets disarm (If I am right)

I once faced this kind of problem. I ended up replacing 1 motor.

As far as I can make out, the direction of rotation of the motors, as well as the fitment of CW/CCW props seems to be correct.

So try this simple solution first:
1. Put 3-4 clicks of LEFT RUDDER trim
2. Put 5-6 clicks of RIGHT AILERON trim.

It may or may not solve the problem.
But if there is any improvement, it will at least help you in figuring out why it flips.

Best of luck.

Thanks all for you reply...I tried changing the FC's direction(Arrow Sign between the two arms) and now I could see a drastic improvement.

Previously the arrow was facing towards the From Left Arm of Quads Forward Position. (But the Off-Set was still set to -45)


However one thing I noticed was the quad is more stable when I switched off the Self Level Setting and it is oscillating more when the Self Level settings is ON.

KK Flight Controller with Self Level settings On  -


KK Flight Controller with Self Level Settings Off -



I think I have to do some corrections in PI ...Will keep you posted. Thanks all for your time