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danfw194 wrote: ↑Mon Oct 16, 2023 14:17
I always wonder how many people get pulled up for offences in average speed camera areas, because a lot of time I've found myself doing exactly the speed limit on a dual carriageway and yet still a steady stream of traffic overtaking me. Do people still not twig how these things work? Do people simply not care? Or do they not prosecute upto say 10% over the limit and people have cottoned onto that?
The latter (I hope!) although some drivers do slow down for each camera so don't understand "average".
I can remember hearing a longish segment on Radio Five Live many years ago that showed how some people have difficulty with this. The presenter - Richard Bacon, if I remember correctly - and several phone-in callers were under the impression that ‘average speed cameras’ meant that two normal speed cameras would take your speed at two locations, say, a mile or two apart and then take the average of those two readings.
While the whole thing was clarified over the course of the discussion, at the beginning they had no idea that what was actually being measured was your average speed between two cameras, rather than the average of your snapshot speed readings at the two cameras.
ravenbluemoon wrote: ↑Mon Oct 16, 2023 18:01
I think it is noted a lot that in 50mph roadworks zones on motorways, most HGV drivers will still be riding the limiter at 56 and get away with it. So you'll often find a platoon of cars cruising along in lane 3 at an indicated 56/57mph, but rarely much faster. Same seems to be the case on the S2 ones around here, if you're not stuck behind a tractor or a Doris in a Yaris.
That is because the ACPO (Association of Chief Police Officers) rules specify a margin which is as I recall 10% plus 3 mph which in practice means that at 57 mph you are unlikely to be prosecuted.
danfw194 wrote: ↑Mon Oct 16, 2023 14:17
I always wonder how many people get pulled up for offences in average speed camera areas, because a lot of time I've found myself doing exactly the speed limit on a dual carriageway and yet still a steady stream of traffic overtaking me. Do people still not twig how these things work? Do people simply not care? Or do they not prosecute upto say 10% over the limit and people have cottoned onto that?
Most average speed installations only have a few of the camera pairs active at any one time. On the A90 between Dundee and Stonehaven, for example, there are only two active pairs but it is not possible for a passing motorist to know with certainty which of the camera pairs are working and which are dummies. However, regular users of the road will know from experience that they can generally push the limit and get away with it most of the time. They know how they work but they also know the chances are that in a 30 mile section of road only a couple of sections are actually enforcing the limit. There was outcry in the local press when the active pairs on the Dunblane to Perth dual carriageway section of the A9 ‘suddenly’ started enforcing the 50mph commercial vehicle limit a few months ago, after several years of operation but only a couple of sections were actually producing tickets.
danfw194 wrote: ↑Mon Oct 16, 2023 14:17
I always wonder how many people get pulled up for offences in average speed camera areas, because a lot of time I've found myself doing exactly the speed limit on a dual carriageway and yet still a steady stream of traffic overtaking me. Do people still not twig how these things work? Do people simply not care? Or do they not prosecute upto say 10% over the limit and people have cottoned onto that?
The latter (I hope!) although some drivers do slow down for each camera so don't understand "average".
I can remember hearing a longish segment on Radio Five Live many years ago that showed how some people have difficulty with this. The presenter - Richard Bacon, if I remember correctly - and several phone-in callers were under the impression that ‘average speed cameras’ meant that two normal speed cameras would take your speed at two locations, say, a mile or two apart and then take the average of those two readings.
While the whole thing was clarified over the course of the discussion, at the beginning they had no idea that what was actually being measured was your average speed between two cameras, rather than the average of your snapshot speed readings at the two cameras.
I think that remains a common misconception, though the number of people who believe it to be true is presumably going down year-on-year because a number of them will learn the truth the hard way. You can see it in action through the average speed cameras on the Westway in London, where there will always be one or two drivers who brake to pass the cameras at or below 30, but then speed up as soon as they've passed them.
ravenbluemoon wrote: ↑Mon Oct 16, 2023 18:01
I think it is noted a lot that in 50mph roadworks zones on motorways, most HGV drivers will still be riding the limiter at 56 and get away with it. So you'll often find a platoon of cars cruising along in lane 3 at an indicated 56/57mph, but rarely much faster. Same seems to be the case on the S2 ones around here, if you're not stuck behind a tractor or a Doris in a Yaris.
That is because the ACPO (Association of Chief Police Officers) rules specify a margin which is as I recall 10% plus 3 mph which in practice means that at 57 mph you are unlikely to be prosecuted.
The guideline is that at 10% +2 mph you will be prosecuted - so in practice the margin is 10% + 1 mph.
AndyB wrote: ↑Mon Oct 16, 2023 16:28
The cameras on the old A1 are no longer listed as active, and nor is the fixed GATSO on the Saintfield Road where one friend of mine got caught three times in the one day.
I wonder if the Saintfield Road one was put out of action when the road was resurfaced to install the pedestrian crossing when the footbridge was removed a couple of years ago, and the calibration lines weren't repainted
AndyB wrote: ↑Mon Oct 16, 2023 16:28
The cameras on the old A1 are no longer listed as active, and nor is the fixed GATSO on the Saintfield Road where one friend of mine got caught three times in the one day.
I wonder if the Saintfield Road one was put out of action when the road was resurfaced to install the pedestrian crossing when the footbridge was removed a couple of years ago, and the calibration lines weren't repainted
Traffic still slows going past it, a useful detterent
In principle calibration lines aren't required if the normal road markings are painted accurately enough. You can see for instance HADECS3 systems on the motorway don't have calibration lines in most areas any more yet you can definitely get a ticket from those.
AndyB wrote: ↑Mon Oct 16, 2023 16:28
The cameras on the old A1 are no longer listed as active, and nor is the fixed GATSO on the Saintfield Road where one friend of mine got caught three times in the one day.
I wonder if the Saintfield Road one was put out of action when the road was resurfaced to install the pedestrian crossing when the footbridge was removed a couple of years ago, and the calibration lines weren't repainted
Traffic still slows going past it, a useful detterent
I think it was decommissioned deliberately because it is now so close to the pedestrian crossing that the likelihood of catching anybody has substantially decreased.
ravenbluemoon wrote: ↑Mon Oct 16, 2023 18:01
I think it is noted a lot that in 50mph roadworks zones on motorways, most HGV drivers will still be riding the limiter at 56 and get away with it. So you'll often find a platoon of cars cruising along in lane 3 at an indicated 56/57mph, but rarely much faster. Same seems to be the case on the S2 ones around here, if you're not stuck behind a tractor or a Doris in a Yaris.
That is because the ACPO (Association of Chief Police Officers) rules specify a margin which is as I recall 10% plus 3 mph which in practice means that at 57 mph you are unlikely to be prosecuted.
The guideline is that at 10% +2 mph you will be prosecuted - so in practice the margin is 10% + 1 mph.
It's usually 10%+ 2 mph, to allow for inaccurate speedometers and to avoid flooding courts with speeding cases. This means so long as you stay below 79 mph, you'll be OK.
danfw194 wrote: ↑Mon Oct 16, 2023 14:17
I always wonder how many people get pulled up for offences in average speed camera areas, because a lot of time I've found myself doing exactly the speed limit on a dual carriageway and yet still a steady stream of traffic overtaking me. Do people still not twig how these things work? Do people simply not care? Or do they not prosecute upto say 10% over the limit and people have cottoned onto that?
I think it is noted a lot that in 50mph roadworks zones on motorways, most HGV drivers will still be riding the limiter at 56 and get away with it. So you'll often find a platoon of cars cruising along in lane 3 at an indicated 56/57mph, but rarely much faster. Same seems to be the case on the S2 ones around here, if you're not stuck behind a tractor or a Doris in a Yaris.
That's my pet hate with lorries. Its 56mph or nothing. Right up your rear end when you are doing 50mph or they go and overtake.
That is because the ACPO (Association of Chief Police Officers) rules specify a margin which is as I recall 10% plus 3 mph which in practice means that at 57 mph you are unlikely to be prosecuted.
The guideline is that at 10% +2 mph you will be prosecuted - so in practice the margin is 10% + 1 mph.
It's usually 10%+ 2 mph, to allow for inaccurate speedometers and to avoid flooding courts with speeding cases. This means so long as you stay below 79 mph, you'll be OK.
Yes, stay below 79 mph as that's the level at which it's prosecuted.
danfw194 wrote: ↑Mon Oct 16, 2023 14:17
I always wonder how many people get pulled up for offences in average speed camera areas, because a lot of time I've found myself doing exactly the speed limit on a dual carriageway and yet still a steady stream of traffic overtaking me. Do people still not twig how these things work? Do people simply not care? Or do they not prosecute upto say 10% over the limit and people have cottoned onto that?
I think it is noted a lot that in 50mph roadworks zones on motorways, most HGV drivers will still be riding the limiter at 56 and get away with it. So you'll often find a platoon of cars cruising along in lane 3 at an indicated 56/57mph, but rarely much faster. Same seems to be the case on the S2 ones around here, if you're not stuck behind a tractor or a Doris in a Yaris.
That's my pet hate with lorries. Its 56mph or nothing. Right up your rear end when you are doing 50mph or they go and overtake.
The other thing I find on the D2 sections of the A66 is there will be a lorry doing 50 mph and another will overtake and hog the outside lane at 56 mph, meaning overtaking the slower moving lorry is futile, as you'll be stuck behind the lorry in the outside lane until he decides to pull in. I saw one who did this on the Appleby by pass last summer.
Glenn A wrote: ↑Sun Oct 22, 2023 16:27
The other thing I find on the D2 sections of the A66 is there will be a lorry doing 50 mph and another will overtake and hog the outside lane at 56 mph, meaning overtaking the slower moving lorry is futile, as you'll be stuck behind the lorry in the outside lane until he decides to pull in. I saw one who did this on the Appleby by pass last summer.
Thats' remarkably considerate of the two lorries. Usually the slower one is doing about 52 and the "faster" one about 54 so even if they both maintain those speeds (which is unusual) it takes an age for them to complete the manoeuver.
Glenn A wrote: ↑Sun Oct 22, 2023 16:27
The other thing I find on the D2 sections of the A66 is there will be a lorry doing 50 mph and another will overtake and hog the outside lane at 56 mph, meaning overtaking the slower moving lorry is futile, as you'll be stuck behind the lorry in the outside lane until he decides to pull in. I saw one who did this on the Appleby by pass last summer.
Thats' remarkably considerate of the two lorries. Usually the slower one is doing about 52 and the "faster" one about 54 so even if they both maintain those speeds (which is unusual) it takes an age for them to complete the manoeuver.
The overtaking lorry has probably reached its limited speed and it is very annoying for cars wanting to get past the slower lorry to find the other lane is occupied as a queue of cars has built up behind the faster lorry.
Glenn A wrote: ↑Sun Oct 22, 2023 16:27
The other thing I find on the D2 sections of the A66 is there will be a lorry doing 50 mph and another will overtake and hog the outside lane at 56 mph, meaning overtaking the slower moving lorry is futile, as you'll be stuck behind the lorry in the outside lane until he decides to pull in. I saw one who did this on the Appleby by pass last summer.
Thats' remarkably considerate of the two lorries. Usually the slower one is doing about 52 and the "faster" one about 54 so even if they both maintain those speeds (which is unusual) it takes an age for them to complete the manoeuver.
The overtaking lorry has probably reached its limited speed and it is very annoying for cars wanting to get past the slower lorry to find the other lane is occupied as a queue of cars has built up behind the faster lorry.
It's the "design fault" of building two-lane dual carriageways - which begs an interesting question - HGVs and trailers are banned from the outside lane of motorways with 3 or more lanes but no such ban applies to the few non-motorways with 3 or more lanes - so does "elephant racing" occur in the outside lane of such non-motorways?
Glenn A wrote: ↑Sun Oct 22, 2023 16:27
The other thing I find on the D2 sections of the A66 is there will be a lorry doing 50 mph and another will overtake and hog the outside lane at 56 mph, meaning overtaking the slower moving lorry is futile, as you'll be stuck behind the lorry in the outside lane until he decides to pull in. I saw one who did this on the Appleby by pass last summer.
Thats' remarkably considerate of the two lorries. Usually the slower one is doing about 52 and the "faster" one about 54 so even if they both maintain those speeds (which is unusual) it takes an age for them to complete the manoeuver.
I once sat behind two lorries on the A14 eastbound for about 10 minutes going near identical speeds. At one moment, one would edge slightly further forwards, but then later that advantage would be lost.
We need a "considerate overtaking" law. If you can't pass within 30 seconds, don't pass. Failure to do so would imply points and a fine. It's not going to make that much of a difference in the long run, if you can't pass within 30 seconds then the speed difference is negligible. Assuming total passing distance is 40 metres, that would be 1.2m/s or about 3 mph. Over a 10 hour shift that's 30 miles of extra progress in the best case. I swear some lorry drivers get off on slowing all traffic down to their speed.
I would quite happily ban elephant racing, but the 30 second rule has a logistical problem.
Say the left hand lane is travelling at 65mph. Am I entitled to lawfully overtake? Yes. Can I do it within 30 seconds without breaking the law? No. Even worse on a 60mph road overtaking a lorry.
Ruperts Trooper wrote: ↑Sun Oct 22, 2023 19:36
It's the "design fault" of building two-lane dual carriageways - which begs an interesting question - HGVs and trailers are banned from the outside lane of motorways with 3 or more lanes but no such ban applies to the few non-motorways with 3 or more lanes - so does "elephant racing" occur in the outside lane of such non-motorways?
I'm only a few fields away from the A46 south of Coventry which is one of those dual carriageways with 3 lanes so I use it quite a lot. I have never seen elephant racing in the outside lane - indeed I don't even recall ever seeing a HGV in the outside lane.
Ruperts Trooper wrote: ↑Sun Oct 22, 2023 19:36
It's the "design fault" of building two-lane dual carriageways - which begs an interesting question - HGVs and trailers are banned from the outside lane of motorways with 3 or more lanes but no such ban applies to the few non-motorways with 3 or more lanes - so does "elephant racing" occur in the outside lane of such non-motorways?
The real problem these days is that most HGV's have a limiter fitted which means they cannot exceed 56 mph which is the result of an EU directive so yes I have seen elephant racing on the A1(M) between Alconbury and Peterborough. HGV's usually just Lanes 1 and 2 but I have had issues with cars towing caravans and large motorhomes in lanes 2 or 3.
I haven't elephant racing in lanes 2/3 on the D3 section of the D3 A19 between Portrack and Norton and its a route I have driven frequently.
Ruperts Trooper wrote: ↑Sun Oct 22, 2023 19:36
It's the "design fault" of building two-lane dual carriageways - which begs an interesting question - HGVs and trailers are banned from the outside lane of motorways with 3 or more lanes but no such ban applies to the few non-motorways with 3 or more lanes - so does "elephant racing" occur in the outside lane of such non-motorways?
The real problem these days is that most HGV's have a limiter fitted which means they cannot exceed 56 mph which is the result of an EU directive so yes I have seen elephant racing on the A1(M) between Alconbury and Peterborough. HGV's usually just Lanes 1 and 2 but I have had issues with cars towing caravans and large motorhomes in lanes 2 or 3.
Elephant racing can be a problem on any motorway - as a caravanner myself I obey the ban on HGVs or trailers in lane 3 of 3 so I'm often blocked by an HGV at 56 mph on their limiter in lane 2 - I've never seen a caravan in lane 3 but plenty of cars/vans towing commercial trailers either ignoring the law or ignorant of it - both the outside lane ban and the reduced speed limit for trailers.
