A driving question for a change!
in [UK Drivers]
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From: DavidR on 12 Feb 2010 19:16 "Nick Finnigan" <nix(a)genie.co.uk> wrote > DavidR wrote: >> "Nick Finnigan" <nix(a)genie.co.uk> wrote >>> 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. Indeed. Please keep up.
From: DavidR on 12 Feb 2010 19:16 "Harry Bloomfield" <harry.m1byt(a)NOSPAM.tiscali.co.uk> wrote in message news:mn.655c7da2c7048a93.106911(a)NOSPAM.tiscali.co.uk... > 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. Yes, that is true so long as you are in L1 during your early approach. It's the ones that you see come round in L2 and move across your intended path into L1 that annoy. > 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. But I don't mind if they do because the space gives plenty of warning. > 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. Hmm. Relying on a lane change to avoid trouble? Very, very dodgy indeed. > As a driver waiting to enter a roundabout, I would personally prefer > drivers taking the exit after my entry point, to be in L1. I think that's weird. >> 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 ;-) Well, thank you. I've never recorded before and I am surprised at the result. The camera was blue-tacked between the dashboard and windscreen and with a post-it-note over the screen to avoid distraction. It might become more of a habit.
From: Nick Finnigan on 13 Feb 2010 11:09 Harry Bloomfield wrote: > 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. No, diagram is perfectly adequate. Changing lanes before exiting is no longer recommended.
From: DavidR on 13 Feb 2010 15:01 "Nick Finnigan" <nix(a)genie.co.uk> wrote > Harry Bloomfield wrote: >> 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. > > No, diagram is perfectly adequate. As I said, the problem is the picture they put in the HC. The scale of the drawing is completely wrong, with road width too wide for the island diameter. Therefore the green arrow shows a car able to straightline from the island to join L1 after the exit without encroaching L1 before the exit. With practical road/island sizes, it is not usually possible to move over before the exit with the neat trajectory shown. > Changing lanes before exiting is no longer recommended. Unfortunately it also says:- "keep to the right on the roundabout until you need to change lanes to exit the roundabout". It's open to misinterpretation by people like Harry.
From: Nick Finnigan on 14 Feb 2010 06:37
DavidR wrote: > > As I said, the problem is the picture they put in the HC. The scale of the > drawing is completely wrong, with road width too wide for the island > diameter. Therefore the green arrow shows a car able to straightline from > the island to join L1 after the exit without encroaching L1 before the exit. > > With practical road/island sizes, it is not usually possible to move over > before the exit with the neat trajectory shown. I don't regard straightlining (as shown) as moving over - the latter would mean driving along the lh lane steering slightly to the right for some distance before steering left again to take the exit. Traffic permitting, you can always straightline the exit (i.e. leave the rh lane steering ahead and pass through the lh lane without steering to the right). |