Mechanics of the bob skeleton and analysis of the variation in performance at the St. Moritz world championship of 2007

The skeleton bobsled is a relatively new discipline of winter sports that competes in the winter Olympic Games. It is a sport with high speeds where fearless determination of the individual slider is required to achieve a winning margin which can be a 100th of a second. Skeleton bobsled requires the athlete to sprint, board a sled (weighing upto 43kg) and slide down a bobsleigh track with their chin just millimetres from the ice at speeds up to 130kmph in a head first position. This paper explores the basic physics that underlie the sport comprising the physics of ice friction, the aerodynamics of the slider, the dynamics of the descent of a curved track, control of direction and position on the track. The rules that govern the sport have a significant impact on the methods whereby performance can be improved and in effect determine the upper limits of achievable speeds. The relative differences in performance between the various competitors are analysed with respect to the published data for the male and female sliders who competed in the 2006/2007 World Championship in St Moritz. It is difficult to identify actual optimum body height and weight but interesting to note that the victors in both the men’s and women’s event were of similar size.