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https://nap.nationalacademies.org/catalog/27432/critical-issues-in-transportation-for-2024-and-beyond

AIMING FOR BETTER HEADLIGHTING

DYNAMIC TESTS WERE CONDUCTED OF THE NIGHT DRIVING SITUATION USING OBSERVER-DRIVERS. TEST METHODS ARE DESCRIBED ALTHOUGH IT IS CONCLUDED THAT A DYNAMIC TEST OF THIS KIND IS STILL NOT FULLY REPRESENTATIVE OF A TYPICAL DRIVING SITUATION. PART OF THE VARIANCE IS THAT OBSERVER-DRIVERS KNOWINGLY ENGAGED IN A TEST, AND THEREFORE THEY WERE PAYING MORE ATTENTION THAN WOULD THE NORMAL DRIVER. THE IMPORTANCE OF PROPER HEADLIGHT AIMING IS EMPHASIZED. TWO RECENT IMPROVEMENTS HAVE RECENTLY BEEN MADE BY MANUFACTURERS: IMPROVED SEALED BEAM LAMPS INSTALLED ON 1956 CARS, AND THE DUAL-UNIT SYSTEM. A CONSIDERABLE INCREASE IN SEEING DISTANCE CAN BE ACCOMPLISHED BY HAVING HEADLIGHTS AIMED EXACTLY RIGHT. ALL SEALED BEAM HEADLIGHTS ARE NOW MANUFACTURED WITH THREE AIMING PADS ON THE FRONT SURFACE OF THE LENS. THE FRONT SURFACES OF THESE PADS ARE CORRECTLY ALIGNED WITH RESPECT TO THE AIM OF THE BEAM. THIS PERMITS THE USE OF SIMPLE, INEXPENSIVE MECHANICAL AIMERS TO SEAT ON THE FRONT SURFACES OF THESE PADS AND TO ALIGN THE LAMPS CORRECTLY WITHOUT THE NEED FOR A DARKENED AREA.

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  • Supplemental Notes:
    • No 191, pp 49-52, 7 FIG, 2 REF Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved.
  • Authors:
    • Roper, Val J
  • Publication Date: 1958

Media Info

  • Media Type: Digital/other
  • Pagination: 4p
  • Monograph Title: Night visibility, 1958
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00220272
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: Sep 12 1994 12:00AM