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hughster wrote:[Compare the reduced-to-S2 A149 (first) with an S2+1 example of apparently equal width on the A47 near Wardley (second):
But if you compare the width of a lorry on it with a decent standard of S2, you can see it is basically the same lane width, just slightly wider hard strips, it's not really near WS2 width so not really much room for three lanes.
It can either be a low standard of one layout or a high standard of another layout - and the latter is going to make a better road for the majority of drivers.
davemase wrote:Coming back from Devon on Saturday and about 1 mile west of Minehead I was amazed to find a section of S3 road with a blind spot halfway along it due to a large 'hump' obscuring the road further on.
Are there any other examples of S3's with blind spots on them still about? Or have they all been removed now.
It was a lovely straight section of road, just perfect for
I wouldn't want to try using the small sections still left on the A6 between Kendal and Shap. The road isn't very busy so you'd probably be OK, but "probably OK" is not good enough to risk your life on!
Helvellyn wrote:I wouldn't want to try using the small sections still left on the A6 between Kendal and Shap. The road isn't very busy so you'd probably be OK, but "probably OK" is not good enough to risk your life on!
I don't know if it's just that I have long experience of these and others don't, but there really is no issue here. It's just like overtaking on a normal S2 road, you need to judge your visibility and relative speeds. On the original location here, on the A39 in Somerset, you can very likely come behind a farm tractor, in which case you can readily nip round it, or someone just a bit slower than you are, which requires more.
I did read a while ago that the Institute of Advanced Motorists found there was an increasing lack of "normal" overtaking opportunities nowadays for them to even test people out on. But if you live somewhere like Hereford, long A-raad S2s in all directions, it's a necessary ability.
Glen wrote:But if you compare the width of a lorry on it with a decent standard of S2, you can see it is basically the same lane width, just slightly wider hard strips, it's not really near WS2 width so not really much room for three lanes.
It can either be a low standard of one layout or a high standard of another layout - and the latter is going to make a better road for the majority of drivers.
I can understand where you're coming from, but I would only agree that a wider S2 is always better than a narrower S2+1 if the road is not over capacity. If it needs more capacity, the road should be widened where physically possible and affordable.
In the case of the A149, based on my own observations, the road is certainly woefully over capacity for much of the year, and because to increase capacity would only involve white paint and catseyes and the resulting standard of S2+1 would match plenty of other examples in successful use on busy trunk routes elsewhere, it seems only natural to me that the road should be widened.
Additionally, any safety risks due to narrower lanes should be balanced against the likely reduction of dangerous overtakes.
South Africa does suicide roads quite well. This is the major highway from Joburg east and the speed limit is 75mph so the traffic speed is more like 85. I wasn't driving so I was able to shut my eyes!
Glen wrote:It can either be a low standard of one layout or a high standard of another layout - and the latter is going to make a better road for the majority of drivers.
Well, the majority of drivers are probably numpties who daren't overtake anything quicker than a tractor. But does that mean that overtaking opportunities should be deliberately removed for those who can?
“The human race divides politically into those who want people to be controlled and those who have no such desire.” – Robert A. Heinlein
drm567 wrote:South Africa does suicide roads quite well. This is the major highway from Joburg east and the speed limit is 75mph so the traffic speed is more like 85. I wasn't driving so I was able to shut my eyes!
David
That's not really a suicide road though is it in the true sense that there is no centre lane that vechicles travelling in opposing directions can use. There are some rare similar stretches like this in the UK - the A1085 past the steel complex near Redcar has a S2+2 with NSL (last time I looked!). With the exception of the speed limit, its lining makes it more dangerous, as the centre line is broken not solid as above, so in theory you could overtake someone overtaking someone else by using one of the two oncoming lanes!!)
For the sake of an extra 3-4m strip of tarmac, many WS2's could have been S2+2s which would be safer. In practice WS2's don't work as most traffic just selfishly sits in the middle of the wide lane rather than tucking themselves on the left side of the lane to allow others to pass.
A42_Sparks wrote:Was there ever any official guidlines or 'etiquette' to using S3 roads when they were more commonplace? They do seem an incredibly risky arrangement to modern eyes, particularly your example Truvelo.
I have a book, dated from the 60s, that goes into great detail how to use an S3. It comes with me to Awaydays, and at least Truvelo and Geo have seen it.
As for S3s, I don't think they're that bad. The recently downgraded one near M5 J26 was certainly never in the local news for accidents, whilst nearby S2 roads frequently were.
It is on a hill climbing towards the Junc 1b of M25/A282.
Problem here is that most people coming uphill seem to think they have a devine right to the centre lane. I overtook someone coming downhill the other day, to be greeted by an oncoming motorist (with no vehicle in inside lane) flashing headlights furiously,with accompanying hand gestures. What a plank.
dartanian wrote:There is still one on the A225 in Dartford.
It is on a hill climbing towards the Junc 1b of M25/A282.
Problem here is that most people coming uphill seem to think they have a devine right to the centre lane. I overtook someone coming downhill the other day, to be greeted by an oncoming motorist (with no vehicle in inside lane) flashing headlights furiously,with accompanying hand gestures. What a plank.
That's a permissive S2+1 marked out for uphill priority, so you should only enter the centre lane going downhill if you are quite certain that there's not going to be anything in it coming the other way.
PeterA5145 wrote:That's a permissive S2+1 marked out for uphill priority, so you should only enter the centre lane going downhill if you are quite certain that there's not going to be anything in it coming the other way.
No it's not - in fact no such markings exist.
These markings just specify that uphill traffic is prohibited from going across into lane 3 to do a double overtake. I know that some have an erroneous perception that they are indicating centre lane priority, but if you look at the markings fully, and in accordance with the Highway Code examples, you will see I am correct.
In theory downhill traffic could take all three lanes, at least according to the markings.
WHBM wrote:No it's not - in fact no such markings exist.
These markings just specify that uphill traffic is prohibited from going across into lane 3 to do a double overtake. I know that some have an erroneous perception that they are indicating centre lane priority, but if you look at the markings fully, and in accordance with the Highway Code examples, you will see I am correct.
In theory downhill traffic could take all three lanes, at least according to the markings.
Yes, that is the strict legal position, but the fact is that this particular marking scheme was widely used in the past to give the psychological impression that the 2 side (very often uphill) has priority, and that is something that most drivers seem to recognise even if the Highway Code doesn't lay it out in words of one syllable. For example here and here.
Unfortunately this is now strongly deprecated for new installations, although in my view in most circumstances it is vastly preferable to the likes of this which prohibit overtaking on the +1 side even when there is entirely adequate forward visibility.
“The human race divides politically into those who want people to be controlled and those who have no such desire.” – Robert A. Heinlein
PeterA5145 wrote:That's a permissive S2+1 marked out for uphill priority, so you should only enter the centre lane going downhill if you are quite certain that there's not going to be anything in it coming the other way.
No it's not - in fact no such markings exist.
These markings just specify that uphill traffic is prohibited from going across into lane 3 to do a double overtake. I know that some have an erroneous perception that they are indicating centre lane priority, but if you look at the markings fully, and in accordance with the Highway Code examples, you will see I am correct.
In theory downhill traffic could take all three lanes, at least according to the markings.
I don't know whether or not this literal interpretation is true, but for whatever reason, my own understanding of 'permissive' S2+1s has always been that 'downhill' traffic should not overtake unless the whole 'uphill' side, both lanes 1 and 2, is clear ahead. The logic is that uphill traffic has priority and should be able to overtake at any point without having to worry about downhill traffic in the middle lane; from a distance, a vehicle heading uphill might be obscuring a following vehicle directly behind it that might at any moment try and overtake without looking for opposing traffic. Just because you can't see any uphill traffic already in the middle lane doesn't mean that it might not appear there halfway through your overtake.
I agree with Peter that the downhill lane should always be separated behind a double white line to remove any ambiguity.
Last edited by hughster on Wed Nov 02, 2011 23:49, edited 1 time in total.
PeterA5145 wrote:That's a permissive S2+1 marked out for uphill priority, so you should only enter the centre lane going downhill if you are quite certain that there's not going to be anything in it coming the other way.
No it's not - in fact no such markings exist.
These markings just specify that uphill traffic is prohibited from going across into lane 3 to do a double overtake. I know that some have an erroneous perception that they are indicating centre lane priority, but if you look at the markings fully, and in accordance with the Highway Code examples, you will see I am correct.
In theory downhill traffic could take all three lanes, at least according to the markings.
I don't know whether or not this literal interpretation is true, but for whatever reason, my own understanding of 'permissive' S2+1s has always been that 'downhill' traffic should not overtake unless the whole 'uphill' side, both lanes 1 and 2, is clear ahead. The logic is that uphill traffic has priority and should be able to overtake at any point without having to worry about downhill traffic in the middle lane; from a distance, a vehicle heading uphill might be obscuring a following vehicle directly behind it that might at any moment try an overtake without looking for opposing traffic. Just because you can't see any uphill traffic already in the middle lane doesn't mean that it might appear there halfway through your overtake.
I agree with Peter that the downhill lane should always be separated behind a double white line to remove any ambiguity.
I strongly disagree that the downhill lane should be separated behind a double white line if there is sufficient visibility to overtake and no traffic coming in the other direction. Stocksbridge bypass is a classic example....
WHBM wrote:No it's not - in fact no such markings exist.
These markings just specify that uphill traffic is prohibited from going across into lane 3 to do a double overtake. I know that some have an erroneous perception that they are indicating centre lane priority, but if you look at the markings fully, and in accordance with the Highway Code examples, you will see I am correct.
In theory downhill traffic could take all three lanes, at least according to the markings.
No, you are incorrect, the "uphill" lanes on a S2+1 are divided by lane divider markings (2m/7m), not centre lines (3m/6m), the same marking as used on dual-carriageways - ie they separate two lanes travelling in the same direction.
Therefore the middle lane is an "uphill" overtaking running lane, whereas traffic on the "downhill" side has to cross a centre line (a DWL broken on their side) to overtake in the same way as overtaking on an S2.
The Highway Code advises against driving in the rightmost lane of a three or more lane single carriageway in any case.
