So having driven the length and breadth of the country over the last week can somebody tell me how the average speed cameras work? Might seem a dumb queston and hey, its friday, so it probably is … but … do they:

A: take a snapshot of your speed at camera one and then do the same at camera two, then compare the two and calculate the average between each shot

OR

B: do they do the above and time you between the shots and work out the total average

record your registration with a time stamp at different positions. So long as they know how far apart they are, they know if you have got between them faster than you should have done.

OR

C: Just make you think they do……..

😀

Stumpy has it – they effectively time you errr time between two known positions, figuring out the average over the distance. Thats why I have to laugh my bits off at people who sail along until they think they are in the range of the sensor and then slam on, then speed up and do the same at the next.

Given the speed people drive through those average speed things, only to slow down for the camera, i don't think your the only one confused.

Does it matter if you change lane?

Apparently you used to be able to beat them by changing lanes, but they've fixed that now.

That's what I read on te interwebz, anyway.

I know somebody (not mentioning any names) who thought that they averaged out the speed of all the cars on the road so "I'm OK because there are loads of people going slow so it will balance out", they must have got lucky because they've never had a ticket. Not sure who would get the ticket if that was the way they worked anyway.

Does it matter if you change lane?

Yes. That was the very early systems, it was rapidly fixed AFAIK.

ed80

By the same token, if everyone drove at the acceptable limit and one bloke went through at 80 (like they do, I'm getting enough miles in through JN25-28 on the M1 currently to know that), knocking the group average over then do we all get tickets as a result. In which case, I'm less than gruntled.

Tell your 'friend' he's a chump, fact.

So if the road is clear, what is to stop you going through the first camera, slow right down for say 90% of the distance, then blast it for the last 10%?

apart from breaking the law, being an ass 😉

"Thats why I have to laugh my bits off at people who sail along until they think they are in the range of the sensor and then slam on, then speed up and do the same at the next."

Probably people trying to get next to a lorry to avoid the camera seeing them.

a few months ago i had to pick someone up from East Midlands airport at 10-ish in the evening – i was coming back northbound through the roadworks on the M1 and a Sainsbury's wagon overtook me as i was sticking to the speedlimit…

given that the lorry driver's job may be at risk should he get any points, i came to the conclusion that he knew something about the average speed camera's on that stretch of motorway that I didn't…

or your speedo is out of calibration.

i know mine is bang on at 50mph and i'm always overtaking people in those zones.

You expect that sort of behaviour from Tesco's and Morrison's, not Sainsbury's. 😡

ski – it was once said that they have the ability to identify speed at a set location too, meaning if you're vastly over they could catch you at one, but I personally dont think they do – having seen the way they work to identify reg numbers.

So if the road is clear, what is to stop you going through the first camera, slow right down for say 90% of the distance, then blast it for the last 10%?

it would be utterly pointless?

you could tank it up to the camera, then sit under it until the time passed, then pass into its FOV.

they do work and are turned on, my company had a van nicked the other day, the thieves disabled the tracker (which is very suspicious, its not apparent it even has one from looking at it or sitting in it, but they disposed of it within seconds of breaking in according to the log)
but the police had records of it passing through the motorway systems so they know roughly where it is.

i believe the reg is taken on all those camera, including the non yellow ones.

the difference is whether they bother to act on the information?

i think they are great, they clearly work.
if they wanted to slow people down, they could just make every gantry mounted camera a speed camera.

or maybe ive got the wrong end of the stick?

The cameras don`t ever need to work to be effective.
I personally do not know of anyone ever caught by one.

WTF I was just wondering and thinking that I've never met anyone that has been caught out by average speed cameras! What happens if you tank it at speed then go off at junction change drivers and tank it through rest of the "run" surely that would totally fox them!

WTF – I dont know anyone who has been caught by an averager either!?

Maybe that's the point of them deceptive and they are nowt!! who knows .. anyone got the balls to tank through a 40 doing say 80 and see what happens 😆

lend me your car then…

Olly, there are plenty of fixed ANPR cameras dotted around the country on motorways (I used to work on the systems), so it's likely they detected the vehicle. I don't know if the speed cameras currently feed into a database the police can search – though there's no technological reason they couldn't.

Quite a few of them are not actively prosecuted by plod. They are generally there to enhance the safety of the people working on the road – and yet a few of them still get killed each year by impatient self important halfwits who think that getting to their golf club 5 minutes earlier is more important than the someone else's life.

Earlier this year Mrs P attended the scene of a guy who'd lost it in a controlled 50mph zone and had ended up with his car pointing the wrong way impaled on the scaffold over a bridge parapet, with one of the tubes going clean through his (fortunately empty) passenger seat. The other good thing is that he did it around 10 mins after the site team had been there checking the scaffolding over.

who think that getting to their golf club 5 minutes earlier is more important than the someone else's life.

While it's good for headlines or shock tactics, that's not the way people think, is it. In all fairness, most people speeding are not thinking "I'm more important, move out of the way" – they're just trying to get somewhere fast without fully appreciating the consequences of a possible (statistically fairly unlikely) event.

I came across a FOI act whilst looking at something at work which referred to the number of people done by the average speed cameras on the M27, asking how many people got done.

I forget the exact figures, but it's something like:

70000 cars/day on that stretch of road
9 months of roadworks/cameras

So… Nearly 2 million cars in the period. Guesses on how many got done for speeding?

1%?
0.1%?

22 people. That's it. I reckon you can go pretty quickly through the cameras without getting done!