Paraglider Reserve Parachute Deployment Under Radial Acceleration

INTRODUCTION: The paragliding reserve parachute system is safety-critical but underused, unstandardized, and known to fail. This study aimed to characterize reserve parachute deployment under radial acceleration to make recommendations for system design and paraglider pilot training.METHODS: There were 88 licensed amateur paraglider pilots who were filmed deploying their reserve parachutes from a centrifuge. Of those, 43 traveled forward at 4 G simulating a spiral dive, and 45 traveled backward at 3 G simulating a rotational maneuver known as SAT. Tests incorporated ecologically valid body, hand, and gaze positions, and cognitive loading and switching akin to real deployment. The footage was reviewed by subject matter experts and compared to previous work in linear acceleration.RESULTS: Of the pilots, 2.3 failed to extract the reserve container from the harness. SAT appeared more cognitively demanding than spiral, despite lower G. Participants located the reserve handle by touch not sight. The direction of travel influenced their initial contact with the harness: 82.9 searched first on their hip in spiral, 63.4 searched first on their thigh in SAT. Search patterns followed skeletal landmarks. Participants had little directional control over their throw.CONCLUSIONS: Paraglider pilots are part of the reserve system. Maladaptive behaviors observed under stress highlighted that components must work in harmony with pilots natural responses, with minimal cognitive demands or need for innovation or problem-solving. Recommendations include positioning prominent, tactile reserve handles overlying the pilots hip; deployment bags extractable with any angle of pull; deployment in a single sweeping backward action; and significantly increasing reserve deployment drills.Wilkes M, Long G, Charles R, Massey H, Eglin C, Tipton MJ.