The Rules of the Air Regulations 2007

General

46.—(1) For the purposes of this Section the horizontal plane of a light shown by 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.

(2) If it is necessary to fit more than one lamp in order to show a light required by this Section because of the physical construction of an aircraft, 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.

(3) If a light is required by this Section 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—

(a)from any point in any vertical plane within those angles throughout angles of 90° above and below the horizontal plane; but

(b)so far as is reasonably practicable, through no greater angle, either in the horizontal plane or the vertical plane.

(4) If a light is required by this Section 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.

(5) Notwithstanding the provisions of this Section the commander of an aircraft may switch off or reduce the intensity of any flashing light fitted to the aircraft if such a light does or is likely to—

(a)adversely affect the performance of the duties of any member of the flight crew; or

(b)subject an outside observer to unreasonable dazzle.