Two visual approach slope indicator lighting systems are in use
in Australasia. These systems are designed to ameliorate and overcome the
visual illusions associated with the approach and landing manoeuvre of
aircraft. Using a flight simulator, 14 student pilot candidates, with little
actual flying experience, ‘flew’ 10 approaches using PAPI and 10
approaches using T-VASIS. The approaches were ‘flown’ in various flight
conditions including low visibility. The visual approach slope indicator
lighting system was randomly assigned to each experimental condition.
Results indicated that overall, there was less deviation from a correct
glidepath when the approaches were ‘flown’ using T-VASIS. A post-flight
survey indicated that participants found T-VASIS to be more intuitive. The
results are discussed with reference to the prevailing preference of PAPI
over T-VASIS by aviation authorities.
