Pitch rotations > 90 in blueprint Transform vars
Rotation is limited by euler angles, kinda complicated stuff but its effects are easy to see - and its probably what you noticed.
wiki on it: https://en.wikipedia.org/wiki/Euler_angles
If you have a 3d program installed you can check this working a bit easier by setting your rotations in the program to enforcing euler angles, usually referred to as using "gimbal rotations", or "gimbal lock" etc.
Hope that cleared it.
answered May 31 '17 at 08:35 PM
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