This SAE Aerospace Recommend Practice (ARP) is intended to cover the external lights on fixed wing aircraft for illuminating the wing leading edge and engine nacelles and the upper surfaces of the wing. The addition of an ice detection system should be implemented when the areas to inspect are not visible from the aircraft cockpit. It is not intended that this Recommended Practice require the use of any particular light source such as Halogen, LED or other specific design of lamp.
Rationale: This document complements current FAA regulations on wing icing detection lights by specifying the light levels and the wing area that is required to be illuminated. Information contained herein has been expanded from ARP4087B in the areas of measurement conditions, lumen maintenance, and the inclusion of specific information relative to the use of Light Emitting Diode source technology. It provides minimum requirements for night operation. However, the Wing Inspection Lights shall be capable of daytime operation as well.