Sector 2 Plan
So I've managed to make this thing work, except that to make it work, the patterns are not spread out evenly. This is going to be a wall of text, representing today's more polished edition of last night's working out.
This edition is based on the City Circle being able to cope with 20tph, which I believe it can, and Sector 2 being able to handle the occasional two-minute headway. It also relies on the use of both the Lidcombe and Homebush turnbacks as well as the Macdonaldtown sidings.
With that declared, this is how it works. Coming out via Museum, we have five patterns of 4tph - two Bankstown, two Airport & East Hills and one East Hills. Coming out via Town Hall, we have four patterns of 4tph. The 4tph that 'vanishes' tips out at Central and reverses Macdonaldtown.
Out via Museum is pretty straightforward, but the headways are not equally spaced out. This is where that occasional two-minute separation is required, because gaps have to be built in to allow an Inner West stopper coming out the other side, forcing the uneven headways onto this side.
This allows us to work with repeated fifteen-minute blocks. Patterns are stated in the down direction because my local station is Central, so I think better in terms of down services, rather than up services.
The patterns are:
- Revesby via Airport
- Liverpool via Bankstown
- Campbelltown via Sydenham
- Macarthur via Airport
- Lidcombe via Bankstown
in that order. Spacing in minutes (leaving Central) is indicated in the numbers in the brackets between patterns.
Out via Town Hall is a little more complicated. Firstly, the Campbelltown via Sydenham expresses are detrained at Central and reversed Macdonaldtown. This opens a seven-minute gap, which allows a stopping train to lag by five minutes; thus, the stopper can take an additional five stops.
The patterns are:
- Glenfield via Granville
- Homebush via Ashfield (this is the stopper)
- Campbelltown via Granville
- Liverpool via Regents Park
in that order. The first value for the first two separations indicates the gaps at Redfern, and the second value the gaps at Ashfield.
By giving the three semi-fast patterns the same number of stops as far as Ashfield (five less than the stopper), they can travel as a 'flight' of three consecutive services, separated by two three-minute gaps. The result is the stopper just being able to fit in, while still permitting the majority of services on the Locals to be semi-fast.
(I have, however, distributed the four remaining less-major stops past Ashfield - Croydon, Burwood, Homebush and Flemington - evenly across the four patterns; this is due to there only being five stops to skip outright. This made for some interesting iterative working-out, but I've managed to make them just fit. The Glenfield service takes an additional stop at Clyde to even its spacing with the Campbelltown service, giving a nearly-even 8tph on the Fairfield branch.)
The specific patterns are:
Out via Musuem
Revesby via Airport
- Central, Green Sq, all to Wolli Ck, all to Revesby
Liverpool via Bankstown
- Central, Redfern, St Peters, Sydenham, Campsie, all to Bankstown, Birrong, all to Liverpool
Campbelltown via Sydenham
- Central, Redfern, Sydenham, Revesby, all to Glenfield, all to Campbelltown
Macarthur via Airport
- Central, Green Sq, all to Wolli Ck, Kingsgrove, Riverwood, all to Glenfield, all to Macarthur
Lidcombe via Bankstown
- Central, Redfern, Erskineville, Sydenham, all to Campsie, Bankstown, Yagoona, Regents Park, Berala, Lidcombe
Out via Town Hall
Glenfield via Granville
- Central, Redfern, Newtown, Ashfield, Strathfield, Flemington, Lidcombe, Auburn, Clyde, Granville, all to Glenfield
Homebush via Ashfield
- Central, Redfern, all to Ashfield, Strathfield, Homebush
Campbelltown via Granville
- Central, Redfern, Newtown, Ashfield, Croydon, Strathfield, Lidcombe, Auburn, Granville, all to Liverpool, all to Campbelltown
Liverpool via Regents Park
- Central, Redfern, Newtown, Ashfield, Burwood, Strathfield, Lidcombe, Berala, Regents Park, Chester Hill, Villawood, Cabramatta, Warwick Farm, Liverpool
I think I've got something here, but please feel free to criticise constructively.
This is a very tight set of patterns - I freely admit this is running it on the edge - but it appears to achieve the goal of nesting a stopper between flights of semi-fast trains, as well as the goal of a more direct service for Liverpool. It achieves this with minimal collateral damage to existing services, and with absolutely no new infrastructure other than that already built as part of Clearways.
It is, however, nearly saturated to begin with and leaves very little 'wiggle room', especially between Sydenham and Homebush via the City Circle.
Congrats on the attempt itself, can be pretty frustrating I imagine. Off-peak perhaps I'd have:
C'town via Sydenham express: Town Hall, Wynyard, Circular Quay, St. James, Museum, Central, Redfern, Sydenham, Beverly Hills, Revesby, Glenfield, all to C'town.
Liverpool via Regents Park express: Museum, St. James, Circular Quay, Wynyard, Town Hall, Central, Redfern, Ashield, Strathfield, Lidcombe, Regents Park, Chester Hill, Cabramatta, Warwick Farm, Liverpool.