What are the vehicle to vehicle distance ( V2V ) behaviors of drivers in your ski
region when driving on mountain highways when there are enough vehicles on a
road that cars back up end to end in a chain and road surfaces contain variable amounts
of snow and ice? In other words not when such highway road surfaces are either dry or
simply wet but rather contain ice and or snow?
Of course when vehicles on slippery road surfaces follow too closely or
tailgate, if a leading vehicle brakes there is a possibility a following
vehicle might cause a rear end collision if they react too slowly and or
braking is not adequate to stop. Generally on level dry pavement surfaces the 2
second rule suffices:
The two-second rule is useful as it can be applied to any speed. It is
equivalent to one vehicle-length (15 feet) for every 8 km/h (5 mph) of the
current speed, but drivers can find it difficult to estimate the correct
distance from the car in front, let alone to remember the stopping distances
that are required for a given speed, or to compute the linear equation on the
fly. The two-second rule gets around these problems, and provides a simple and
common-sense way of improving road safety.
For instance 40mph/5mph = 8 car lengths. 60mph/5mph = 12 car lengths (180
feet). And obviously when road surfaces are icy/snowy the safe distance increases. V2V distance also decreases more as downhill gradient increases as well as when roads bend and turn. And V2V distances increase as uphill gradient increases.