[TORTUGA]

Originally posted by badmanners
a system that has been used in the past on known static positions is for the officer to have 2 prominent landmarks in view, as the vehicle passes one landmark he starts counting, as the vehicle passes a second landmark he stops. Times under a pre equated figure=ok
times over it and you are probably speeding.
not an exact science but it lets him pull ya and can do a character assessment from there. ie: likelihood of person to speed+type of vehicle+time past landmarks=make cheque payable to Chief Constable


The system you describe is called VASCAR. It calculates your average speed over a given distance. Like you say the police will use bridges, shadows or those little white squares painted on the road surface. These are there for that purpose so they can clock you between the 2 points.
www.abd.org.uk