The "Tangential arc" connects tangential to the first toolpath point of the drive surface. The orientation of the arc is 90° to the tool axis. So the arc orientation also depends on the side tilt orientation of the tool.
In the example the tool is tilted under 45° to the side. So the arc orientation is also 45° to the drive surface. Setting a side tilt angle of 0° the arc would come vertical from below. With 90° side tilt angle the arc comes horizontal from the side.