Controlling head-lamp aim. Paper resented at the 50th Annual Meeting of the Highway Research Board HRB, Washington, D.C., January 1971.

In his study of vehicular head lamps, the author found that high percentage of in-service vehicles have lamps that are improperly aimed. Lamps installed and aimed properly are found to become misaligned rather quickly, even in normal routine operation of the vehicle. the author has also identified faults in new lamp units that preclude proper aim if installed and adjusted according to standard practice, as well as lamp housing features that are inherently unstable.