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+---- Thread: 3 to 4 aspects and 4 to 3 aspects braking distance definition?? (/showthread.php?tid=1982)
3 to 4 aspects and 4 to 3 aspects braking distance definition?? - railkim - 28-09-2015
May I know my understanding of 3 to 4 aspects and 4 aspects to 3 aspects braking distance definition is correct or not?
The definition is in the attachment for comment. Thanks
RE: 3 to 4 aspects and 4 to 3 aspects braking distance definition?? - PJW - 28-09-2015
(28-09-2015, 05:10 PM)krailkim Wrote: May I know my understanding of 3 to 4 aspects and 4 aspects to 3 aspects braking distance definition is correct or not?
The definition is in the attachment for comment. Thanks
The important thing is the aspect sequence displayed; your diagrams are rather too simplistic for meaningful comment.
You need to think about a Red in each of the signals and what signal is at braking distance from it that gives the first warning. For 3 aspects transitioning onto 4 aspects there is the problem that for one signal there is no signal positioned a braking distance on its approach- there is "no one always best" solution, but several possible "workaround" options and the skill is choosing the best for the site circumstances.
suggest you look at Bite Sized Revision Notes 05extra in the Mod 3 Signalling Principles Queries area of this website.
RE: 3 to 4 aspects and 4 to 3 aspects braking distance definition?? - railkim - 29-09-2015
Hi PJW
The material is useful. Thanks for pointing me in the right direction.
Kim