Commercial pilots endure multiple stressors in their daily and occupational lives which are detrimental to psychological well-being and cognitive functioning. The Quick coherence technique (QCT) is an effective intervention tool to improve stress resilience and psychophysiological balance based on a five-minute paced breathing exercise with heart rate variability (HRV) biofeedback. The current research reports on the application of QCT training within an international airline to improve commercial pilots\' psychological health and support cognitive functions. Forty-four commercial pilots volunteered in a one-month training programme to practise self-regulated QCT in day-to-day life and flight operations. Pilots\' stress index, HRV time-domain and frequency-domain parameters were collected to examine the influence of QCT practice on the stress resilience process. The results demonstrated that the QCT improved psychophysiological indicators associated with stress resilience and cognitive functions, in both day-to-day life and flight operation settings. HRV fluctuations, as measured through changes in RMSSD and LF/HF, revealed that the resilience processes were primarily controlled by the sympathetic nervous system activities that are important in promoting pilots\' energy mobilization and cognitive functions, thus QCT has huge potential in facilitating flight performance and aviation safety. These findings provide scientific evidence for implementing QCT as an effective mental support programme and controlled rest strategy to improve pilots\' psychological health, stress management, and operational performance.

This study investigates the effect of quick coherence technique (QCT) on commercial pilots\' resilience to the unprecedented impact of a pandemic. Eighteen commercial pilots voluntarily participated in a 2-day training course on QCT followed by 2 months of self-regulated QCT practicing during controlled rest in the flight deck and day-to day life. There are subjective and objective assessments to evaluate the effects of QCT on commercial pilots\' psychophysiological resilience. Results demonstrated that QCT training can significantly increase pilots\' psychophysiological resilience thereby improving their mental/physical health, cognitive functions, emotional stability and wellness on both subjective (PSS & AWSA) and objective measures (coherence scores). Moreover, pilots who continued practicing self-regulated QCT gained the maximum benefits. Current research has identified great potential to enhance pilots\' mental/physical health via QCT training. Operators can develop peer support programs for pilots to increase resilience and maintain mental and physical health using the QCT technique. Practitioner summary: QCT breathing has been proven to increase commercial pilots\' resilience by moderating psychophysiological coherence, strengthening mental/physical capacity and sustaining positive emotions to deal with the challenges both on the flight deck and in everyday life.HIGHLIGHTSPilots have suffered from the impact of the Covid-19 pandemic across many factors including social, economic, mental, physical, emotional, and operational issuesBiofeedback training can increase commercial pilots\' resilience by moderating psychophysiological coherence, strengthening mental and physical capacitySelf-regulated practicing QCT to form a habitual behaviour is required to sustain the maximum benefits either in the flight or day-to-day lifeQCT is an effective intervention for aviation authorities and airline operators to develop peer support programs to increase pilots\' fatigue resilience.