On Thu, 20 Jan 2005, Dave Arquati wrote:
Dan Gravell wrote:
wrote:
I'd advocate six, but I think 8 is unrealistic - major stations aside
(East Croydon, Wimbledon etc) how many routes have 8tph?
Put simply - build them. You're right that few have 8tph, but the
setting of the waterline at four seems more a decision based on
marketing than it does the semantics of the word "frequent".
I think a 15 minute interval is just enough to qualify - after all,
given that the average wait should be 7.5mins, that's just enough time
at the big terminals to buy a ticket and find the platform if you're
unfamilar with the place.
I think worst-case time is more important than average - i want to know
i'm not going to have to wait longer than a given time.
4tph is also the off-peak frequency to London at Richmond, Ealing
Broadway (District) and Rickmansworth outwards. I accept that that's a
small proportion of stations.
Basically, where NR and LU share (how about the Bakerloo?) - it should be
banned!
And no, Ealing Broadway isn't shared, but that's not important right now.
It is interesting that 6tph is "standard" offpeak Tube frequency on
outer London Tube services like the Central line's West Ruislip branch
or the Piccadilly's Rayners Lane branch, whereas 4tph is deemed
sufficient on National Rail, even at inner London stations like
Loughborough Junction, Streatham Hill, Deptford and St Johns.
This must be some new meaning of the word 'interesting' of which i was not
previously aware - a synonym for 'criminal', i take it
.
Add most of the West Anglia line that list (not Hackney Downs or Tottenham
Hale, though) - in fact, i think it's even less above Hackney (Cambridge
Heath etc).
6 tph should be the benchmark for 'frequent' service. 8 tph should be an
aspiration. 4 tph is absurd.
Also, those six trains should be evenly spaced. Perhaps the rule should
actaually be no more than 10 min between departures; 6 evenly-spaced tph
would satisfy this, but 8 tph would be needed if they weren't even.
Oh, and the map should deal with the multiple-destinations problem by
treating services to different destinations as separate lines; i don't
think a station on two infrequent lines should be count as frequently
served, but i don't think it's entirely clear.
tom
--
Socialism - straight in the mainline!