INTRODUCTION: The authors have developed the measuring system which detects both ski deflection and ski-snow contacting pressure during the actual turn on the snow surface. The detail is described in another paper in this Conference. In this study, measured result on a long turn is shown and the relation between the ski deflection and the ski-snow pressure is investigated. METHOD: A skilled skier performed a long turn at the snow slope using the ski that has a deflection sensor beam on the upper surface and pressure sensors installed along the ski edge, The length of the ski was 1750mm with side curve radius 24m.The slope angle was about 20degrees. The distance between the turn changes was 40m and the half width amplitude was 6m. The skiing speed was about 20m/s. RESULTS: An example of the deflection profile of the outside ski during the turn is shown in Fig.1. Minor vibrating deflection combined in the main change. The change in the value of the deflection well agreed with that of foot load. The frequency of the minor deflection vibration was near the free Vibration frequency of the ski. The deflection in the front part of the ski had a good relation with the pressure applied on the bottom surface in the front part of the boot center. Pressure increases around the boot center from 350mm front to the 150mm behind. DISCUSSION: Using the data on the shape of the cross section of the snow groove in the turn trajectory, the contacting Situation between the edged the deflected ski and the snow surface is estimated. The deflected ski crushes to the snow surface to make a trajectory groove. The increase of the pressure on the ski causes the increase of the ski deflection. CONCLUSION: The deflection of the ski, foot load and the pressure applied on the bottom surface of the ski had good relations with each other in the long turn.
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