ADUK Archive

I was driving through the roadworks on the M6 in the Midlands where it's being converted into a smart M-way. The work goes on for 6.5 miles and straddle a junction so I passed Average Speed cams at the start of the roadworks and a 2nd set immediately after the junction before reaching the final set at the end.

I wasn't speeding but wondered if the average speed is calculated over the entire 6.5 miles or for each section ie from the start to the junction and a second time from the junction to the end?

TIA

I think they just calculate average speeds between the cameras rather than as a whole section.

I agree - I think they are in adjacent pairs but I suppose there is nothing to stop them linking up ones that are further along. Why do you ask?

There is a stretch of road about a mile from where I live that's 30mph residential. The total length is approximately 1 mile. There are three average speed cameras spaced out at intervals of about 500yds. To be honest I wouldn't know whether they're linked or not.

Surely it would be pointless to link them. You can't speed over the entire stretch without speeding on at least one individual section........

Makes them more effective if one camera cannot read a plate, for example, if other vehicles in the way.

I work on the basis that if any two cameras record your registration then your speed can be calculated.

Re why I asked the question, I set cruise control to the 50 limit and was in a line of cars but was passed by several others going at least 5mph faster. As the 2nd section is shorter, it didn't seem long enough for them to slow down to average 50.

If you are basing on your speedo then it is possible you were actually going a slow as 45 mph most over-read by around 10% so they may have been a lot closer to the limit than you thought. Several of the satnags offer a speed camera database and the device calculates your average speed over the whole area warning you if you are exceeding the limit.