To investigate the prevalence of fatigue and the effects of special service convalescence, and to analyze factors associated with fatigue in helicopter pilots.

A single center observational study was employed, selecting helicopter pilots undergoing convalescence at a rehabilitation and recuperation institution from April 2024 to August 2024. A general information questionnaire and the Chinese version of the Multidimensional Fatigue Inventory 20 (MFI-20) questionnaire were selected to assess the fatigue scores of 437 helicopter pilots. Basic flight and demographic data were collected, and routine blood tests, biochemical tests, as well as relevant imaging examinations were further conducted. Comparisons of demographic and clinical characteristics between fatigued and non-fatigued groups were performed using independent samples t-tests and chi-square tests. Furthermore, data from improved and non-improved subgroups within the fatigue cohort were compared. Multiple logistic regression analysis was used to analyze the factors influencing fatigue improvement among helicopter pilots.

Of the 437 questionnaires retrieved, 379 were valid. A total of 379 helicopter pilots were enrolled, including 150(39.58%) in the fatigue group and 229(60.42%) in the non-fatigue group. Compared with the non-fatigue group, the fatigue group exhibited significantly higher age [32.0(27.5, 38.0)years, 30.0(26.0, 34.0)years, Z=-3.429, P< 0.01], a greater proportion of personnel with flight hours ≥1 000 h [56.67%(85/150), 39.30%(90/229), χ²=10.997, P< 0.01], and a higher prevalence of transport helicopter pilots [59.33%(89/150), 48.47%(111/229), χ²=4.290, P< 0.05]. Significant difference was also observed in the regional distribution across units (χ²=19.717, P< 0.01). Flight personnel with more than one COVID-19 infection or persistent post-COVID-19 symptoms beyond three months exhibited a higher prevalence of fatigue (χ²=6.524, 16.897, all P< 0.05). Following standardized convalescent care, the discharge fatigue score (35.27±12.07) was significantly lower than the admission score (37.60±11.45, t=4.919, P<0.01). Among the fatigued cohort, the proportion of smokers was significantly higher in the non-improved subgroup [75.93%(41/54)] than in the improved subgroup [32.29%(31/96)]. Smoking emerged as a significant independent factor associated with fatigue improvement (OR=0.151, 95%CI: 0.071-0.322, P< 0.01).

Standardized recuperation effectively alleviates fatigue among helicopter pilots. Higher age, extended flight hours, piloting transport helicopters, duty station location, repeated COVID-19 infections, and persistent symptoms 3 months post-COVID-19 represent major risk factors for fatigue. Smoking may significantly impede fatigue recovery.