Speed on entrance and exit from termini

[800002]

Lowestoft used to/may still be, 60mph straight out of some of the platforms I believe.

NESA implies this still is the case.
There is a '55' marked, on the Up, between Lowestoft SB and Oulton Broad North Jn, between 23m 16c and 22m 58c.

 

[hexagon789]

NESA implies this still is the case.
There is a '55' marked, on the Up, between Lowestoft SB and Oulton Broad North Jn, between 23m 16c and 22m 58c.

The 55 is new I think, if I'm remembering correctly the Lowestoft line was 60 throughout (with a few 10 mph points in the station itself) except for the two swing bridges and the approach to Reedham.

 

[800002]

The 55 is new I think, if I'm remembering correctly the Lowestoft line was 60 throughout (with a few 10 mph points in the station itself) except for the two swing bridges and the approach to Reedham.

Here is the relevant NESA page (1-April-2019).
(apologies if it is a tad small in the writing)

Yes, to the 10 mph points, at the station end.
I don't know what the 55 mph restriction might be for.

 

[The Planner]

On numerous occasions I've stopped in the station throats of Paddington; Kings Cross; and Euston - mostly due to running a minute or two early, and thus having to either wait for the platform to become available or to allow a departing service to clear the route forward into the platform.

If trains arrived quicker (in succession / time) at certain stations, they wouldn't be able to be accommodated due to having full platforms. By slowing things down on the approaches there is more time to turn the previous arrivals around and get them departed before the next wave of arrivals.

Additionally, if there is a red aspect (signal) at the last gantry before the terminus - for conflicting departures for example - they will have to start slowing on the approach to the Double Yellow (about 1.5 miles out in the case of paddington). If there is a lot of point work to negotiate in the throat, this could be another reason to be going slowly - passengers standing in the vestibules are more easily thrown about than those in seats.

Its the nature of the beast to arrive slightly early as the vast majority of terminii will have engineering/box time on the approach. You shouldn't be planning trains without an eye on the platforming anyway and if it does cause an ongoing problem then the turnaround times should be challenged.

 

[hexagon789]

View attachment 67924 View attachment 67924
Here is the relevant NESA page (1-April-2019).
(apologies if it is a tad small in the writing)
View attachment 67924
Yes, to the 10 mph points, at the station end.
I don't know what the 55 mph restriction might be for.

That's definitely changed, it used to be 60 throughout.

 

[800002]

Its the nature of the beast to arrive slightly early as the vast majority of terminii will have engineering/box time on the approach. You shouldn't be planning trains without an eye on the platforming anyway and if it does cause an ongoing problem then the turnaround times should be challenged.

With places like Paddington, a lot of the time additional padding is required to make the conflict margin of a departing service across the path of the incoming service.
In the Dec 19 timetable it's all been validated near perfectly, as it stands at the moment with the planned LTP diagrams.
Once the operator starts to amend these, STP alterations make it very difficult to platform everything compliantly without adding time to the incoming service. All the turnaround time / max dwell times are within the rules, but it's the sheer quantity of services which makes it difficult.

GWR, especially, issue their amended diagrams about 7-10 days out (when they've bid something completely different, ie without amended diagrams, at T-18.
NR have to plan on what the Operator bids, when the operator doesn't know with certainty what they diagrams will look like.

The issue being NR offer the paths the operator wants, at T-14, and then the operator tells NR at T-2 when the diagrams are, and then NR amends the platforming for them. (speaking of GWR, here). If there isn't enough space, tuff! Make room...

 

[The Planner]

I know how it works, ive done it for long enough...

 

[carriageline]

It may also be down to how tight station throats are. Keeping the speed low means you can have sharper curves and pointwork.

Increase the line speed, and the points and curves have to be shallower, thus making them longer, moving the throat further from the station. This will then eat into capacity.

Lower speeds also mean you get shorter signal sections, which can help improve capacity.

 

[306024]

It may also be down to how tight station throats are. Keeping the speed low means you can have sharper curves and pointwork.

Increase the line speed, and the points and curves have to be shallower, thus making them longer, moving the throat further from the station. This will then eat into capacity.

Lower speeds also mean you get shorter signal sections, which can help improve capacity.

Compare Liverpool St with Paddington as an example of what you are saying. Platform reoccupation at Liverpool St is far sharper than at Paddington.

It would be interesting to know how the design for the current layout at Paddington was arrived at, and whether if the designers had their time again they would do anything different, even without the Ladbroke Grove crash.

 

[MarkyT]

Compare Liverpool St with Paddington as an example of what you are saying. Platform reoccupation at Liverpool St is far sharper than at Paddington.

It would be interesting to know how the design for the current layout at Paddington was arrived at, and whether if the designers had their time again they would do anything different, even without the Ladbroke Grove crash.

Paddington throat is much longer and wider than that at Liverpool Street, which is constrained in a deep retained cutting and a parallel tunnel on a very tight curve. There was much less scope for speed increases at Liverpool Street for approach and departure when the layout was renewed. With the revised speeds at Paddington after the Ladbroke Grove review, it's possible that some of the turnouts, especially those very close to the ramp ends, might have been specified marginally slower and cheaper than in the initial 1990s remodelling, but overall the new layout is still highly fit for purpose.

 

[800002]

Compare Liverpool St with Paddington as an example of what you are saying. Platform reoccupation at Liverpool St is far sharper than at Paddington.

I don't think I am able to comment on what goes on at Liverpool Street.

It would be interesting to know how the design for the current layout at Paddington was arrived at, and whether if the designers had their time again they would do anything different, even without the Ladbroke Grove crash.

Orginally, the steamers arrived into the topside (high numbers) and we're dragged out to Old Oak to be serviced, etc. The empty stock then came back over the ECL into the bottom side (low number) for boarding.
There wasn't really a need for crossing the whole throat to the low side, as there is now.
As it started off with Brunel, room for change was fairly limited, which is probably why it is as now. Little modification after little modification slowly makes an increasingly used railway evermore difficult to navigate and improve without ripping the whole thing up and relaying it.

 

[trebor79]

The train frequently trundles into Liverpool Street, and can take an inordinate amount of time to cover the short distance from Stratford or Bethnal Green, particularly if running early.
Likewise it's not uncommon to trundle out until some point after Stratford, presumably due to all the suburban stoppers and conflicting moves.
A few weeks ago I observed a queue of 6 or 7 suburban services stacked for miles out of Liverpool Steet.
It's a much more crowded railway than ever before. Presumably if we were building these stations and their approaches from new, we wouldn't have throats where 4 or 6 tasks fan out to serve 18 platforms, you'd start widening the formation several miles break with flying junctions and diveunders.
As a passenger the solution is to stay sat in my seat until we have arrived. I can live with it taking me 30 seconds longer to get to the tube.

 

[Meerkat]

I travel off peak. It’s more than 30 seconds - if you don’t get to the doors early you get trapped by families putting themselves back together again for five minutes and people with seemingly their entire possessions packed into suitcases!
Particularly off peak (commuters know the drill generally) I think it is good PR for staff to add in an explanation if there is one. “We got here a bit early so need to wait for a platform” is a positive thing and tells people they aren’t really being held up.