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Age characteristics of the formation of fatigue in military helicopter pilots

ISSN 2223-6775 Ukrainian journal of occupational health Vol.19, No 2, 2023

Age characteristics of the formation of fatigue in military helicopter pilots

Kalnysh V.V.1,2, Trynka I.S.2, Pashkovskyi S.M.3, Bohush H.L.3, Koval N.V.3, Pashkovska O.V.4
1State Institution «Kundiiev Institute of Occupational Health of the National Academy of Medical Science of Ukraine», Kyiv
2Ukrainian Military Medical Academy, Kyiv
3Military Medical Clinical Center of the Central Region, Vinnytsia
411th regional military medical commission, Vinnytsia

Full article (PDF): ENG / UKR

Introduction. In the modern war, aviation occupies a leading place, therefore, all issues that increase the quality of the professional activity of the State Aviation acquire primary importance. During the operation of the aircraft, the pilot develops a state of fatigue, which integrally reflects the influence of a complex of harmful factors and the deterioration of the quality of information processing, reduces attention, the speed of their reactions, and thus the risk of fatal errors arises. A new modern factor that burdens the functional condition of flight crew and aviation personnel is the time awake at night, due to the active use of their mobile phones and tablets to connect to Facebook, Twitter, Instagram and other social networks. Today, fatigue is not considered a condition that is a contraindication to flight clearance. This is due to the lack of reliable methods for assessing the level of fatigue, especially in people of different ages, the absence of approved legal acts for determining acceptable levels of fatigue, the lack of trained specialists for assessing the level fatigue, etc. Now when martial law is in force, there is an urgent need to assess the level of fatigue of flight crew members and aviation personnel who are actively performing combat tasks. The importance of the discussed problem increases due to the involvement in flights of pilots of various ages, qualifications and experience of working in combat conditions, which is reinforced by the shortage of personnel and the state policy, aimed at the maximum protection of life and health of servicemen. Considering the above, the study of the age-related features of the formation and development of fatigue in military pilots is an urgent issue today.

The purpose of this study is to generalize the experience of psychophysiological reactions associated with the development of fatigue in military helicopter pilots of various ages, taking into account their professional activities in a real theater of war.

Research materials and methods. In order to identify the age-specific features of the development of fatigue in military helicopter pilots, 573 relevant specialists aged 22 to 59 years were selected during the period of inpatient medical-flight examination based on the Department of Psychophysiology and Psychology of the Military Medical Clinical Centre of the Central Region. The examination was carried out with help of the “PFI-2” software and hardware complex for psychophysiological research. The organization and methods of examinations were developed on the basis of theoretical and practical approaches.

The results. An external indicator, which to some extent is reflected in the development of fatigue in military helicopter pilots, from the moment after the end of vacation to the moment of the examination, excluding the initial phase of training and stabilization of the level of work capacity, reflects the tendency of the loss of functional reserves of the pilots` body. It is worth noting that in helicopter pilots of different ages, the process of fading functional reserves and increasing the level of fatigue can occur at a fairly different speed. In order to exclude the influence of fatigue mechanisms implemented in other age groups, four separate age ranges were analyzed: 20-29, 30-39, 40-49 and 50-59 years old. In the age range of 50-59 years, the largest number of informative indicators is observed, 8.75% of which refer to speed characteristics. The remaining parameters relate to concentration of attention (12.5%) and short-term visual memory (12.5%). The coefficient of multiple correlation in this case is R=0.62 (p=0.005). The next age range 40-49 years has a smaller number of informative indicators (6). Among them, 33.3% are speed characteristics, 50.0% are indicators of reaction to a moving object, and 16.7% are indicators of short-term visual memory. The multiple correlation coefficient between these psychophysiological parameters is R=0.27 (p=0.04). The development of fatigue in helicopter pilots in the age range of 30-39 years has 5 informative indicators. Among them, 60.0% refer to speed characteristics and 40.0% to spatial orientation indicators. The multiple correlation coefficient between these psychophysiological parameters is R=0.29 (p=0.013). The age range of 20-29 years is represented by 6 informative indicators. An interesting fact is that among these indicators, only 16.7% belong to the group of speed reactions, 50.0% of indicators characterize spatial orientation, and 33.3% of psychophysiological characteristics relate to the assessment of short-term memory. The multiple correlation coefficient between these psychophysiological indicators is R=0.32 (p=0.006). Summarizing the obtained results for all age groups, it is worth noting that the percentage of use of fast reactions associated with fatigue tends to decrease in helicopter pilots from older to younger age. This trend is especially noticeable in the 50-59 and 20-29 age groups. It turns out that at an older age, speed reactions suffer the most. Therefore, fatigue, which manifests itself to a greater extent at the age of 50-59, is closely related to the speed reactions that are most vulnerable for this age, and vice versa, qualitative and stable speed reactions are more characteristics at a young age. The contribution of cognitive functions in the discussed range of age groups has the opposite trend. That is, with a decrease in age in the analyzed groups, there is an increase in the contribution of cognitive functions associated with the development of fatigue. Both noted trends are proof of the fact of a gradual decrease in speed characteristics with age and an increase in the contribution of cognitive functions in young helicopter pilots. Another important feature of the development of fatigue emerges from the conducted multiple stepwise correlation-regression analysis. The calculated correlation coefficients are structured in the following series: 0.62 (50-59 years), 0.27 (40-49 years), 0.29 (30-39 years), 0.32 (20-29 years). Such a profile of the change in correlation coefficients can be explained by greater intensity of fatigue formation processes in older age groups of helicopter pilots, when the reduction of their speed capabilities is more closely related to a violation of the functional state; the degree of connection of psychophysiological functions with pronounced fatigue is approximately the same in all other age groups and is at an average level, which indicates the presence of significant compensatory capabilities in helicopter pilots aged 20-49 years. Thus, each age group of helicopter pilots has its own specifics of the development of fatigue, but the general pattern of changes in a number of individual psychophysiological characteristics with age is maintained.

Conclusions. Specific features of the development of fatigue in military helicopter pilots who directly participated in hostilities have been determined. It is shown that each age group has a specific connection for this group with a complex of psychophysiological functions aggregated with the state of fatigue. This effect is especially evident in older (50-60 years) by speed functions and younger (20-29 years) by cognitive functions. A complex of informative indicators related to the development of fatigue in helicopter pilots of various ages was identified, on the basis of which equations were constructed to estimate the level of fatigue. Ways of practical application of the invented psychophysiological effects in practice by assessing the level of fatigue in military helicopter pilots to determine the strategy for restoring their psychophysiological status and training the relevant psychophysiological functions, taking into account their age criteria, are discussed.

Keywords: age characteristics, fatigue, psychophysiological characteristics, military helicopter pilots, speed reactions, cognitive functions.


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