Roger wrote:
Quote:
And I’d say the only independent means of confirming slip is to ask the driver of the car being targeted what speed he was showing on his Speedo.
Sadly not accurate, because the answer would invariably be 25, 35, 45, 55 or 65 depending on the limit in force.
I was looking at this hypothetically. If a Lti 20-20 was being used to measure the speed of a car, say doing 30mph, the only way you would know if the instrument being used to measure that speed was accurate would be if someone was sitting in the car and driving it at an indicated 30mph (ok allow 10% over for Speedo error) the instrument would have to read between 30-33 mph, if it didn’t then the instrument is either inaccurate, or you are getting slip. Unless you know the true speed of the car you target you would not know if you are getting slip.
You couldn’t use another instrument as collaboration because you wouldn’t know if you where getting slip from that instrument. That’s what I meant when I said you would have to ask the driver of the car (This could be a police officer or whoever) and that’s why some people have complained that they where not speeding, it’s your word against the operators, and the operator would not know if he was getting slip because he does not know the speed of the car.
That’s how they proved they where getting slip when they done the tests with the American version of the Lti 20-20. They had someone in the vehicle keeping it at a constant speed (which I think was 30mph) but the instrument was reading a much higher speed than 33mph.