Psychomotor Alertness and Subjective Fatigue in Helicopter Pilots

Fatigue poses a significant safety risk in helicopter operations; however, subjective assessments of fatigue based on an individual's perception, awareness, and insight, such as self-perceived tiredness, may not accurately reflect objective performance impairment as identified by standardized tests or measurement tools. In this context, the present study investigated the relationship between subjective drowsiness and objective alertness performance among helicopter pilots during operational tasks using a computerized psychomotor vigilance task (PVT).

This observational field study initially included 20 helicopter pilots. Complete pre- and postflight measurements were available for 15 pilots and were included in the final analysis. Subjective sleepiness was assessed before testing using the Karolinska Sleepiness Scale. Objective alertness was measured pre- and postflight using a PVT; mean reaction time (ms) was used as the primary outcome variable.

The mean subjective sleepiness score was 3.98 ± 1.27 (range: 2.0-6.9). Mean PVT reaction time increased from 461.2 ± 118.1 ms preflight to 516.3 ± 100.8 ms postflight (an 11.9% increase), reaching statistical significance with a medium-to-large effect size (Cohen's dz = 0.65). Considerable interindividual variability was observed. Correlation analysis revealed a weak association between subjective sleepiness and postflight PVT reaction time (r = 0.16, P = 0.573), with prolonged reaction times observed in some pilots reporting low subjective sleepiness.

Combining objective alertness measures with subjective scales may improve fatigue risk management. Gevrek I, Eroglu C. Psychomotor alertness and subjective fatigue in helicopter pilots. Aerosp Med Hum Perform. 2026; 97(8):633-637.