Acceleration and Braking Performance of Snowmobiles on Groomed/Packed Snow 2011-01-0287

There are limited scientific data available on the acceleration and braking performance of modern snowmobiles. In this study we investigated the acceleration and deceleration characteristics of four modern snowmobiles of varying engine size (500 to 1000 cc) and style (2-stroke and 4-stroke) on groomed/packed snow conditions. The acceleration tests were performed at quarter, half and full throttle. The deceleration tests were performed using full braking with locked tracks and rolldown with power both on and off. Target test speeds ranged from 20 to 60 km/h. Snow condition parameters were measured throughout the tests. The results of the acceleration tests showed that at higher speeds, higher horsepower rating generally corresponds to higher acceleration rates, with a maximum observed average acceleration of 0.70g. The results of the full braking deceleration tests found no significant difference between snowmobiles or test speed, with the range of deceleration rates ranging from 0.32 to 0.42g. Rolldown tests showed that deceleration increases with speed and that there is no significant difference between rolldown deceleration in the power on and power off conditions. These test results will allow accident reconstructionists to better quantify vehicle speeds in snowmobile incidents in similar snow conditions.