Usability of Light-Emitting Diodes in Precision Approach Path Indicator Systems by Individuals with Marginal Color Vision

Details

• Creators:
  Milburn, Nelda J. ; Gildea, Kevin M. ; Perry, Deborah L. ; Roberts, Carrie A. ; Peterson, Linda
• Corporate Creators:
  Civil Aerospace Medical Institute
• Subject/TRT Terms:
  • Color blindness
  • Vision tests
  • Light emitting diodes
  • Human subject testing
  • Approach
  • Landing aids
  • Feasibility analysis
• Publication/ Report Number:
  DOT/FAA/AM-14/6
• Resource Type:
  Tech Report
• Geographical Coverage:
  United States
• Corporate Publisher:
  United States. Office of Aerospace Medicine
• Abstract:
  To save energy, the FAA is planning to convert from incandescent lights to light-emitting diodes (LEDs) in ; precision approach path indicator (PAPI) systems. Preliminary work on the usability of LEDs by color vision-waivered pilots (Bullough, Skinner, & Milburn, 2012) indicated that red weak (protan) individuals made a few ; errors identifying red. Hence, this follow-up study explored whether clustering LEDs of different chromaticities ; of the same hue would aid users with color vision deficiencies (CVD). ; Participants, aged 18-33 years, included 45 with normal color vision (NCV). Additionally, 48 were diagnosed ; using the Colour Assessment and Diagnosis (CAD) test as 27 deutans (including five subjects with potential ; deutan deficiencies), 11 protans, two tritans, and eight subjects evidencing both red-green and yellow-blue ; deficiencies. Participants completed the Dvorine pseudoisochromatic plate test, the Signal Light Gun Test (which ; is the secondary test for issuing color vision waivers), the Cone Contrast Test, and a simulation of the PAPI ; system. Participants were asked to name the colors of a 4-light, color-coded PAPI simulation using typical red (R) ; and white (W) light configurations resulting in five possible patterns (WWWW, WWWR, WWRR, WRRR, and ; RRRR) composed of either incandescent lights, or clusters of three monochromatic or three heterochromatic ; 5mm cylindrical LEDs. ; Analyses did not indicate any significant differences between the incandescent, monochromatic, and ; heterochromatic conditions. A between-group analysis found that a group comprised of those with both red-green ; and yellow-blue deficiencies performed significantly worse than all other color vision groups. Performance was ; not significantly different among all other groups. The protan group performed perfectly on all light sources, even ; on the 16 trials without comparative color luminance cues. ; This finding suggests that color vision-waivered pilots will perform the same on red and white LED PAPI ; systems as with the current incandescent system.
  More +
• Format:
  PDF
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/27427/dot_27427_DS1.pdf
• File Type:
  [PDF - 1.11 MB]
• Collection(s):
  FAA Civil Aerospace Medical Institute ; US Transportation Collection
• Main Document Checksum:
  urn:sha256:c8c529257219113b3aefe290f8a33b1f9eb1f8564c150f6ca59a7df92f53b06c