Approach Lighting Aiming Criteria

A method of determining the elevation setting angles for approach lights based upon fundamental principles has been developed.  This method considers the effects of the applicable decision height, the required visual range, the glide slope angle, the distance of the light from the threshold, and the vertical beam spread of the light.

This method, defined as the visual segment method, has been compared with other methods and found to be preferable.

Elevation-setting-angles have been computer for the lights of the MALSR and ALSF-2 approach-light systems when lamped with the types of lamps presently in service.

The suitability of the intensity distribution characteristics of the lights currently used in U.S. approach-light systems has been analyzed and possible changes noted.

Author: Charles A. Douglas