The flow field in the near wake of a 1:5.5 bobsleigh model was investigated by means of stereoscopic particle image velocimetry. The time-averaged flow field revealed two counter-rotating vortices and a strong downwash between them. From the velocity field, the aerodynamic drag was retrieved invoking the conservation of momentum. This approach enabled relating the aerodynamic loads with the flow structures responsible of the loads. Measurements were repeated with different front-cowling rotations between 0° and 20°. It was found that small nose rotations allowed a drag reduction by approximately 5%, whereas for nose rotations exceeding 10° the drag coefficient remained approximately constant.
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