Effect of long flights on the cognitive performance of air crew.

The cognitive performance of groups of subjects was tested after flights lasting between 7.5-9.5 hours to the north, east and west of Sydney (ns = 10, 12, and 12) and compared with the performance of a ground-based control group (n = 12). Analysis showed an impairment in performance of the flight groups following the flights. The analysis suggests that part of the performance change following transzonal flights may result from stress induced during the flight rather than adjustment to new time zones.