Helicopters and periscope.

[aleksey 1]

If you put a helicopter on the map (in flight) with the appointment of a player - Gunner, it is impossible to look through the scope, the image is just as close when holding the right mouse button.

If you get in into a helicopter from the ground then everything works correctly.

[Nicholas 5]

I would recommend that you add this bug to the ArmA 3 feedback tracker.