Paragraph 8 General

For the purposes of this section of these Rules the horizontal plane of a light shown in an aircraft means the plane which would be the horizontal plane passing through the source of that light, if the aircraft were in level flight.

Where by reason of the physical construction of an aircraft it is necessary to fit more than one lamp in order to show a light required by this section of these Rules, the lamps shall be so fitted and constructed that, so far as is reasonably practicable, not more than one such lamp is visible from any one point outside the aircraft.

Where in these Rules a light is required to show through specified angles in the horizontal plane, the lamps giving such light shall be so constructed and fitted that the light is visible from any point in any vertical plane within those angles throughout angles of 90 degrees above and below the horizontal plane, but, so far as is reasonably practicable, through no greater angle, either in the horizontal plane or the vertical plane.

Where in these Rules a light is required to show in all directions, the lamps giving such light shall be so constructed and fitted that, so far as is reasonably practicable, the light is visible from any point in the horizontal plane and on any vertical plane passing through the source of that light.