Analysis On Different Flying Mental Stress Correlation With Flight Performance And Personal Factors

Objective：To study HR, HRV and score of pilots with different flying conditions（including two-seater flying exam and first solo flight）, and the correlation betweenmental stress and flying score of pilots, and influencing factors of mental stress. Then toprovide some methods and physiological evidence for evaluation of mental stress andrecruition and training of pilots.Methods：20fighter pilots were randomly selected to wear a equipment testingtheir physiological index to continuously record ECG in30minutes peaceful state onthe day before the flight. On the days of two-seater exam and first solo flight, the pilotswore the equipment to continuously record ECG respectively. HRV was analyzed withData Analysis System applied with the record equipment. The scores of pilots withpeaceful state, two-seater exam and the first solo flight were compared. Meanwhile, thescores of pilots were compared between two-seater exam and the first solo flight. Thenthe relationship between scores and HRV indexes was studies by correlation analysis.Study pilot social-domestic information (BMI, smoking state, residence, andeducational level) was obtained using the questionnaire. The association between studypilot social-domestic information characteristics and mental stress were evaluated usingthe Pearson χ2-test.Results: The change of HR and HRV frequency domain indices with differentflying conditions：(1)Average heart rate of two-seater exam and the first solo flightwere significantly higher than that in peaceful state(P﹤0.01). No significantlydifference was observed between two-seater exam and the first solo flight (p>0.05).(2)HR, HRV frequency domain indices (LF power and LF/HF) in two-seater exam andthe first solo flight phase were significantly higher than those in peaceful state(P﹤0.01), while HF power was significantly lower(P﹤0.01).(3) LF/HF of two-seater exam wassignificantly higher than that of the first solo flight (p<0.05), but no significantlydifference in LF power and HF power were observed(P＞0.05).Correlation between mental stress of student pilots with different flyingconditions and flight performance:(1) Flying score of first solo flight phrase wassignificantly higher than that in two-seater exam phrase (4.70±0.18vs4.565±0.173,P<0.05).(2)LF power was positively correlated with flying scores of two-seater examand first solo flight and the correlation coefficients were0.51and0.56(p<0.05),respectively.(3) HF power was negatively correlated with flying scores of two-seaterexam and first solo flight and the correlation coefficients were-0.655and-0.495(p<0.05), respectively.(4) LF/HF power was positively correlated with flying scores oftwo-seater exam and first solo flight and the correlation coefficients were0.79and0.58(p<0.05), respectively.Personal factors to mental stress:(1) HF power of obesity was lower thanthose of control group in peaceful state (p<0.05), LF power and LF/HF power of obesityin all flying conditions were higher than those of control group, but no significantlydifference was observed (p>0.05).(2) LF power and LF/HF were higher than those ofcontrol group in two-seater exam (p<0.05).(3) No significantly difference was observedamong different residence (p>0.05) and different education level (p>0.05).Conclusions: All the pilots have certain strength mental stress, including activationof sympathetic nervous system and inhibition of parasympathetic one, in bothtwo-seater exam and the first solo flight phrase. The results of this study demonstratethat there were significant correlations between HRV indexes of pilots (LF, HF andLF/HF) and flying score. BMI and smoking had some influences on mental stress.Frequency domain indexes of HRV can be used as a measuring index flight stressintensity.