Abstract

The jumper's surface area and velocity vector have a relationship with aerodynamic force with respect to the flight length. Therefore, it is important to know how aerodynamic force affects the athlete and skis during the flight phase. Three forces act on jumpers: aerodynamic force, moment force, and gravity in the flight phase. A jumper's surface area and his velocity mainly decide the aerodynamic force. The surface area is calculated from the attack angle of the velocity vector during the flight phase. The jumper's action in the flight phase can vary the attack angle. Changes of the body position in the flight phase affect aerodynamic factors. A jumper's height and ski length are two of the factors that determine the frontal surface area. This is an important factor for individual jump performance. It is important for jumpers to decide an adequate ski length. Furthermore, eddy and turbulence are created behind the jumper in relation to his body shape and the air flow. Perhaps resulting from the eddies, the aerodynamic force acting on the jumper varies. These variations dominate changes in the jumper's velocity vector. These velocity vector variations occur in a periodic fashion. It is important to study the basal relationship of the jumper and aerodynamic force during flight. The purpose of this study is to clarify the substantial behavior of aerodynamic force on jumpers. Einleitung (gekürzt)