Evaluating the Impact of Flight Hours on Pulmonary Function in Military Pilots

Military pilots are routinely exposed to environmental stressors such as hypoxia, dry air, and G-forces, which may affect pulmonary function. Although spirometry is performed regularly to assess flight fitness, the long-term effects of flying on lung function remain unclear.

This retrospective study analyzed data from the Center for Man in Aviation of the Royal Netherlands Air and Space Force, encompassing two parts. First, all medical assessments from 2012 to early 2025 were reviewed to determine how often pilots were declared unfit to fly due to abnormal spirometry. Second, a Generalized Estimating Equation model was used to assess the effect of cumulative flight time, smoking status, and age on the forced expiratory volume in 1 s/vital capacity (FEV1/FVC) ratio using data collected between 2012 and mid-2019 (before the adoption of standardized Z-scores).

Out of 9182 assessments, 3 pilots were deemed unfit to fly solely due to an abnormal spirometry. In the Generalized Estimating Equation analysis of 4558 assessments, flight hours showed a nonsignificant trend toward a positive, albeit clinically irrelevant, association with FEV1/FVC. There was no significant difference between aircraft types or between former and never-smokers. FEV1/FVC declined significantly with age and was significantly lower in current smokers compared to never-smokers.

Pulmonary abnormalities rarely led to unfit declarations and no evidence was found for a negative long-term effect of military flying on pulmonary function. Age and smoking status were significant predictors of FEV1/FVC decline. These findings may inform future refinement of pulmonary assessment protocols for military pilots. Konings M, Wiekenkamp AC, Wingelaar-Jagt YQ, Wingelaar TT. Evaluating the impact of flight hours on pulmonary function in military pilots. Aerosp Med Hum Perform. 2025; 96(12):1079-1083.