Post by mrfs42 on Aug 26, 2009 21:09:18 GMT
Non-timetable types look away - you've been warned!
Thanks to ducatisti (TVM) I've not got a copy of the TTN for the '38 run, which has got some times to the ¼ min, like the Central and the Drain.
This got me thinking, so I started digging out various recent TTNs for the Jubilee out of the pile - I have a couple of questions...
I knew that the ¼ min resolution came in with the current WTT, but the only real comparison that I have is the Christmas TTN for last year (yes, there were a few days when the Jubilee ran trains over Christmas) as I've not seen a copy of the current WTT:
Where exactly are the limits of the finer resolution times - JLE only? Looking at what I've got in front of me, it only seems to apply from Canning Town eastward, could someone confirm that please - or if you're feeling generous, could I have an extract of the off-peak running times please?
Developing from that, and rooting around in the bowels of the Christmas TTN, there seems to be something slightly unusual about the S/EB runtimes between the Staff Platform and Stratford.
Now I understand completely about platform weighting and stand time *but* this is something different. During the early part of the morning before 0916 on 24th December and a similar sort of time on the 31st December the runtimes go in an approximate cycle of (all in minutes) 2½, 3¼, 2¾, 4¼ on the S/EB into Stratford. Nothing exceptional really, when you think that this involves waiting at signals for platform clearance/occupancy. Butbutbutbut the pattern isn't constant throughout the day. After 0916 it stablises with only the odd deviance for headway or layover smoothing [1] - is this the case in the current WTT? N/WB runtimes from Stratford are fixed in what I can find. Has anyone noticed that you wait outside Stratford for a platfom more in the morning than in the evening?
[1] Well, I *might* be over-egging the pudding here, perhaps I'm thinking more of transitional runtimes on the shoulders of the busy services - the pattern of deviance is emerging the more I look at the Christmas TTN, and correlate the runtimes to the number of trains in service - this is where tph becomes meaningless especially when you're dealing in multiples of 15 seconds (a small, but occasionally significant time).
;D
The perils of TT modelling and staging several vlookups (one for runtime according to time, then one according to available or destination platform, then another one according to which platfom the departing train that will pass the arrival has departed from) ;D
Thanks to ducatisti (TVM) I've not got a copy of the TTN for the '38 run, which has got some times to the ¼ min, like the Central and the Drain.
This got me thinking, so I started digging out various recent TTNs for the Jubilee out of the pile - I have a couple of questions...
I knew that the ¼ min resolution came in with the current WTT, but the only real comparison that I have is the Christmas TTN for last year (yes, there were a few days when the Jubilee ran trains over Christmas) as I've not seen a copy of the current WTT:
Where exactly are the limits of the finer resolution times - JLE only? Looking at what I've got in front of me, it only seems to apply from Canning Town eastward, could someone confirm that please - or if you're feeling generous, could I have an extract of the off-peak running times please?
Developing from that, and rooting around in the bowels of the Christmas TTN, there seems to be something slightly unusual about the S/EB runtimes between the Staff Platform and Stratford.
Now I understand completely about platform weighting and stand time *but* this is something different. During the early part of the morning before 0916 on 24th December and a similar sort of time on the 31st December the runtimes go in an approximate cycle of (all in minutes) 2½, 3¼, 2¾, 4¼ on the S/EB into Stratford. Nothing exceptional really, when you think that this involves waiting at signals for platform clearance/occupancy. Butbutbutbut the pattern isn't constant throughout the day. After 0916 it stablises with only the odd deviance for headway or layover smoothing [1] - is this the case in the current WTT? N/WB runtimes from Stratford are fixed in what I can find. Has anyone noticed that you wait outside Stratford for a platfom more in the morning than in the evening?
[1] Well, I *might* be over-egging the pudding here, perhaps I'm thinking more of transitional runtimes on the shoulders of the busy services - the pattern of deviance is emerging the more I look at the Christmas TTN, and correlate the runtimes to the number of trains in service - this is where tph becomes meaningless especially when you're dealing in multiples of 15 seconds (a small, but occasionally significant time).
;D
The perils of TT modelling and staging several vlookups (one for runtime according to time, then one according to available or destination platform, then another one according to which platfom the departing train that will pass the arrival has departed from) ;D
. I suppose it would have helped if I had looked through everything beforehand because the preamble to WTT 5 reads: 'quarter-minute resolutional timings have been introduced between West Ham and Stratford. I can't see the wood for the trees!!!
