The Usefulness of the Proximate Status Indication as Represented by Symbol Fill on Cockpit Displays of Traffic Information

Traffic Alert and Collision Avoidance Systems (TCAS) displays depict traffic advisories, resolution advisories, and information on other aircraft. Symbols for other aircraft include the proximate status indication where the symbols of “proximate” (close) aircraft are filled and the symbols of “non-proximate” (more distant) aircraft are not filled. This web-based study examined the value of the proximate status indication as represented by symbol fill to assess implications for Cockpit Displays of Traffic Information (CDTIs), and found no advantage for it, only a disadvantage. Pilots viewed videos of traffic displays. Analysis of the data failed to show a benefit of the proximate status indication for estimating threat and potential for visual acquisition of traffic. Analysis did find a decrement in performance for identifying the greatest traffic threat, when the proximate status indication was depicted. In contrast to their performance, most pilots say the proximate status indication is useful. However, results indicate that pilots overemphasize proximity and underemphasize closing speeds when assessing threat levels. This bias may account for the pilot preference for displaying proximate status. Results of this study are intended to be of use to the Federal Aviation Administration in developing guidance material for CDTIs.

  • Record URL:
  • Corporate Authors:

    Research and Innovative Technology Administration

    Volpe National Transportation Systems Center, 55 Broadway
    Cambridge, MA  United States  02142

    Federal Aviation Administration

    800 Independence Avenue, SW
    Washington, DC  United States  20591
  • Authors:
    • Zuschlag, Michael
    • Chandra, Divya C
    • Grayhem, Rebecca
  • Publication Date: 2013-6


  • English

Media Info

  • Media Type: Digital/other
  • Edition: Final Report
  • Features: Appendices; Figures; References; Tables;
  • Pagination: 106p

Subject/Index Terms

Filing Info

  • Accession Number: 01490000
  • Record Type: Publication
  • Report/Paper Numbers: DOT-VNTSC-FAA-13-03, DOT/FAA/TC-13/24
  • Contract Numbers: FA6YC1 HD5RG; FA6YC3 JT532; FA6YC3 KT532
  • Created Date: Aug 1 2013 10:40AM