Rock climbing falls can be safely stopped and are often a routine part of the sport. However, safety may be compromised not only by equipment failure but also due to the climbers’ misjudgment of the situation. Current literature and other resources are either based on laboratory experiments or lacking specific and systematic measurements of the relevant parameters of lead climber falls. Only one recent theoretical paper describes the physics of lead climber falls under realistic conditions. To provide research-based safety guidance for the climber community systematic studies of various scenarios are needed.
In this study experimental data were collected and analyzed from lead climber falls on an actual climbing route, recording all positions prior to and after the fall as well as climber and belayer acceleration data. The data reveal the actual fall height, the forces acting on belayer and climber and the dissipation mechanisms of the fall energy. Two test series were performed, varying the fall height or the belayer mass, respectively. Substantially longer total fall heights are found, in particular for lighter belayers, even for relatively short falls. The major mechanisms to dissipate the energy are the energy losses when accelerating the belayer of the ground and the friction force in the loaded carabiner. The study concludes with recommendations for best practice under various conditions for a safe climbing experience.