Anybody who wants to know why you feel like you are flying level in a commercial plane when turning could look up 'Coordinated flight".  The tl;dr simple explanation is that if the pilot just rolls a plane to the left you feel a force to the left (as 'down' is now to your left), if the pilot just yaws to the left you feel a centrifugal force to the right (as you are changing your direction of momentum which otherwise would carry on straight ahead).  Using the right balance of roll, yaw and pitch results in a coordinated turn that is most comfortable and aerodynamically efficient.  A tilting train achieves much the same thing by controlling its roll angle.