The objective of this study is to reveal the optimum condition that makes the longest flight distance for the flight phase of ski jumping. In other words, the question is how a jumper should control their posture such as the body-ski angle (forward leaning angle) from start to finish to achieve the longest flight distance. Our study was in two parts. The first was obtaining experimental data for an aerodynamic database, and the second was then to optimize the flight distance utilizing the aerodynamic database. We solved the fully optimization problem taking account of the equation of motion on the basis of aerodynamic data. Aerodynamic data are acquired for a wide variety of the angle of attack, the forward leaning angle and the ski-opening angle with a full size model of a ski jumper mounted in the 3-meter low speed wind tunnel. In the optimization study, the forward leaning angle is taken as a control parameter for the maximum flight distance. The result is summarized as follows. In order to reach the maximum flight distance, a jumper should keep their deep forward leaning angle, that is about 6° during the flight. The flight distance is more sensitive for the head wind velocity than the jumper's skill.

DESCENTE SPORTS SCIENCE Vol.24/THE DESCENTE AND ISHIMOTO MEMORIAL FOUNDATION FOR THE PROMOTION SPORTS SCIENCE