Article,
Optimization of the flight technique in ski jumping: The influence of wind
Journal of Biomechanics, (May 2019)
DOI: 10.1016/j.jbiomech.2019.03.023
Abstract
Ski jumping performance is strongly affected by wind. Flight technique optimization for maximizing jump length is a highly complex motor-control task that also depends on the wind. Pontryagin's minimum principle was used in this study to gain a better understanding on how wind influences flight technique optimization. Optimum time courses of the angle of attack $\alpha$ of the skis and of the body-to-ski angle $\beta$ were computed for seven realistic wind scenarios on the large hill and on the flying hill. The optimum values of $\alpha$ were smaller at headwind, and larger at tailwind when compared to the optimum time course at calm wind. The optimum values of $\beta$ were the smallest possible ones at the given flight technique constraints, except for the last part of the flight. Optimum adjustments of $\alpha$ increased the jump lengths between 0 and 1.8 m on the large hill, and between 0 and 6.4 m on the flying hill. Maximum jump length increases were achieved at the highest headwind speed. Even larger jump length effects can be achieved by using smaller $\beta$-angles, which might be possible in headwind conditions, but this is associated with increased problems to keep the flight stable.
