Subjective evaluation of the performance of alpine skis and correlations with mechanical ski properties

Abstract

The competition between ski and binding manufacturers is very strong. The purchase decision of customers is occasionally based on ski testing by the customer himself, but often the purchase decision mainly relies on published results of commercial ski tests. In this study we analysed evaluation methods and results of five important ski tests for the winter season 2004/2005, whose results were published in skiing related media. All of those tests are very extensive, but they differ strongly in their evaluation methods, in the skiing skill of their testers, and, hence, in the results and purchase recommendations they give. From our point of view it is a shortcoming of all of these ski tests that while they established a very sophisticated testing procedure, they neither evaluated mechanical properties of the tested skis, nor did they record the snow conditions during their tests. Whether a ski exhibits a good performance or not, depends not exclusively on the properties of the ski, but rather on the properties of the whole system athlete-binding-ski and the interaction of this system with the type of snow present during the test. To analyse these interrelations we conducted a ski test with five testers and five pairs of skis. The ski testers were all experienced, sport-orientated skiers. The snow conditions during the tests were hard snow with a good grip. Subsequent to the subjective evaluation of the ski performance in the field tests all ski-binding combinations were tested in the laboratory for their bending and torsional properties. On the one hand, the results of our study underline the strong differences in the subjective assessment of the ski performance. On the other hand indications for correlations between bending and torsional stiffness of the skis and the grades they achieved in the subjective assessment for the specific conditions were found. We also analysed that changing external conditions affect strongly the outcome of the subjective ratings. © 2006 Springer-Verlag New York.