25.1.8.270 Single-Beam Road Lighting Equipment

Head lamps arranged to provide a single distribution of light shall be permitted on rotor vehicles manufactured and sold prior to July 1, 1953, in lieu if multiple-beam road lighting equipment herein specified if the single distribution of light complies with the following requirements and limitations:

(a) The head lamps shall be so aimed that when the vehicle not loaded none of the high-intensity portion of the light shall at a distance of 25 feet ahead project higher than a level of 5 inches below the level of the center of the lamp from which it comes, and in no case higher than 42 inches above the level on which the vehicle on which the vehicle stands at a distance of 75 feet ahead.