A driving question for a change!
in [UK Drivers]
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From: DavidR on 12 Feb 2010 12:23 "Nick Finnigan" <nix(a)genie.co.uk> wrote in message news:hl1far$upk$1(a)news.eternal-september.org... > DavidR wrote: >> >> Oh, to you and Harry in particular, notice that there are 4 vehicles >> exiting >> east which are not following the Highway Code's (daft) suggestion to >> spiral >> out.. > > They are following Highway Code rule 186 to: > keep to the right on the roundabout until you need to change lanes to exit > the roundabout > > even though it would be quicker and shorter to move change lane just as > they exit. Where does the HC say to spiral out? The picture in the HC shows a not very common roundabout layout, drawn to an unrealistic scale, with some arrows on it. The arrows look convincing at first sight except that on a true scale it rarely works as drawn. Some people take the arrows as a suggestion that a spiral is the preferred option.
From: DavidR on 12 Feb 2010 12:35 "Harry Bloomfield" <harry.m1byt(a)NOSPAM.tiscali.co.uk> wrote > DavidR expressed precisely : >> In other words, all 4 cars should have circulated throughout in L1. > > I did not say that! No, but it is the only logical conclusion of saying:- "Occupying any other lane than L1 without good reason is poor lane discipline." I took this for my amusement http://www.david.eazyrider.co.uk/public/camera/AVI_0083.AVI shows a sequence of three roundabouts (27MB) http://www.david.eazyrider.co.uk/public/camera/AVI_0083_0001.AVI is the roundabout in question - being the middle of the three (9MB) I will refer to this one in the timings. > Unless there is good reason not to, the lead car in that picture should > have moved over to L1 - there was no reason for him/her not to. Using L1 > when going 3/4 way round would be wrong, Stop the video at 10 seconds. You will notice the roundabout symbol has thick lines showing the main route and thin lines showing minors. That's normally a pretty good indicator to "use either lane". > but we don't know where these cars actually entered the roundabout from. Doesn't matter. When passing the N junction, someone going W-E is in exactly the same position as someone going S-E. Similarly, if someone was to go S-N in L2 they would be in no different a position from someone going E-N in L2. There is no particular logic why a particular lane must be associated between an entry and an exit. Besides, as we know from the signs, S-E is the main route so that is where the majority of traffic will be going so we have a safe assumption that that is what you are seeing. > Holding onto L2, without a good reason to do so, Keeping a distance from an entry point is a very good reason. No different from trying to avoid making leftward lane changes next to slip roads on motorways or going L3 to L2 in the blindspots of drivers in L1 (which can be a source of varying degrees of frustration to faster drivers behind). Stop the video at 34 seconds. The Focus is between the N entry & exit. Using the cross hatching on the right you can place us on the aerial view. Is this where you think a lane change should occur? I know the camera's view is limited but left hand apex is clearly too far to the right to steer smoothly. Move on to 36 seconds. I'm now roughly where the fourth car is in the aerial view and am only now aligned to apex. It could possibly be straightlined from here but it would still eat into rolling space for anybody entering left. The first reasonable opportunity to make the change would be when aligned to the road ahead at 40 seconds. When are you going tell us where the point of conflict is by staying in L2? > is a constant source of frustration on the road. The sequence between entry and exit was 9 seconds. I was in L2 for just 5 seconds after this but had the Focus changed lane I would have overtaken it. Keeping to lane on a roundabout for a few seconds has nothing to do with lane hogging. If you look at the longer video and move to the third roundabout, had L2 been best lane on entry, then again, I would have held it through the exit (look at the car waiting left). It's possible I might have moved to L1 briefly before the next queue.
From: Nick Finnigan on 12 Feb 2010 15:29 DavidR wrote: > "Nick Finnigan" <nix(a)genie.co.uk> wrote in message > news:hl1far$upk$1(a)news.eternal-september.org... >> DavidR wrote: >>> Oh, to you and Harry in particular, notice that there are 4 vehicles >>> exiting >>> east which are not following the Highway Code's (daft) suggestion to >>> spiral >>> out.. >> They are following Highway Code rule 186 to: >> keep to the right on the roundabout until you need to change lanes to exit >> the roundabout >> >> even though it would be quicker and shorter to move change lane just as >> they exit. Where does the HC say to spiral out? > > The picture in the HC shows a not very common roundabout layout, drawn to an > unrealistic scale, with some arrows on it. The arrows look convincing at > first sight except that on a true scale it rarely works as drawn. Some > people take the arrows as a suggestion that a spiral is the preferred > option. There is no hint of a spiral, absolutely no suggestion of changing lane before passing the previous entry, and no indication that straightlining from the rh lane of the roundabout to the lh lane of the exit is preferred to the option adopted by the 4 vehicles shown on google maps.
From: Harry Bloomfield on 12 Feb 2010 17:52 DavidR formulated the question : > Keeping a distance from an entry point is a very good reason. There trade offs to using both L1 and L2. L1 means you will be closer to them as you pass them, but their vision of your vehicle will often be better because there is less liklehood of their A frame hiding your approach. Your eye contact with them is also improved from L1. As I have already suggested, your using L2 can often tempt them out into your path and if you are looking to take the next exit - that can be the point of conflict you mentioned. In L1, assuming you have nothing to your right, you still have the option to move to your right if they fail to stop or drift forward. As a driver waiting to enter a roundabout, I would personally prefer drivers taking the exit after my entry point, to be in L1. > Stop the video at 34 seconds. The Focus is between the N entry & exit. Using > the cross hatching on the right you can place us on the aerial view. Is this > where you think a lane change should occur? Difficult to tell from a video or a map view - I would need to be behind the wheel to make a definitive reply. http://www.david.eazyrider.co.uk/public/camera/AVI_0083.AVI Nice, fast and smooth progress BTW ;-) -- Regards, Harry (M1BYT) (L) http://www.ukradioamateur.co.uk
From: Harry Bloomfield on 12 Feb 2010 18:01
Nick Finnigan was thinking very hard : > There is no hint of a spiral, absolutely no suggestion of changing lane > before passing the previous entry, and no indication that straightlining from > the rh lane of the roundabout to the lh lane of the exit is preferred to the > option adopted by the 4 vehicles shown on google maps. Agreed - The only way they could fully explain it with diagrams, would be via a series of diagrams covering each possible option of passage through a roundabout. -- Regards, Harry (M1BYT) (L) http://www.ukradioamateur.co.uk |