Turn-back Sidings

[bramling]

Rather than at a busy station, I would have thought that a turnback one station beyond a busy station would be more useful - that way the train can 90% empty out at the busy station, and then at the quiet station it would be a much easier process to empty the train fully at a quieter platform. I'd always thought that might be one of the reasons why Hyde Park Corner is the central station with a crossover on the Picadilly line, as it would be one of the quieter places to reverse a train if one end of the line is blocked, rather than doing it at Green Park or another busy interchange.

Yes that may work well in certain cases, however your Hyde Park Corner example is more coincidence by design. Unfortunately in reality many people nowadays take no notice of publicly or announcements, so your quiet station may still find itself overwhelmed by people suddenly finding the train is terminating.

There’s little evidence to suggest any of this has been taken into account - for example the Jubilee Line Extension’s reversing points are London Bridge, Waterloo and Canary Wharf - not exactly the quiet stations!

 

[Enthusiast]

...and Canary Wharf - not exactly the quiet stations!

Indeed not. One of only two stations outside Zone One to be in the top ten busiest stations (the other being Stratford - which entered the charts in 2012) and the busiest station served by a single line.

 

[AlbertBeale]

Indeed not. One of only two stations outside Zone One to be in the top ten busiest stations (the other being Stratford - which entered the charts in 2012) and the busiest station served by a single line.

Served by a single line - Stratford? What about the tuppeny tube?

 

[Enthusiast]

Sorry, possibly my poor construction. Canary Wharf is the busiest station served by a single line. Cut out the bit in brackets about Stratford and it makes sense.

 

[AlbertBeale]

Sorry, possibly my poor construction. Canary Wharf is the busiest station served by a single line. Cut out the bit in brackets about Stratford and it makes sense.

Hi - sorry - as much my rushed reading as your poor construction!

 

[philthetube]

Yes that may work well in certain cases, however your Hyde Park Corner example is more coincidence by design. Unfortunately in reality many people nowadays take no notice of publicly or announcements, so your quiet station may still find itself overwhelmed by people suddenly finding the train is terminating.

There’s little evidence to suggest any of this has been taken into account - for example the Jubilee Line Extension’s reversing points are London Bridge, Waterloo and Canary Wharf - not exactly the quiet stations!

Indeed, on Met trains reversing at Moorgate drivers usually make PA announcements at Barbican advising people to change there, avoiding having to cross platforms, but many arrive at Moorgate, and some remain on the train and end up travelling back to Farringdon and changing there, despite announcements and visual info

 

[Rogmi]

I created a separate thread regarding a change to the Carto Metro address. As there are links to the Carto Metro site on this thread, I'll repeat the new address here:

Cartes détaillées - Metro, Tramways et funiculaires de France, Suisse et d'Italie (Plan des voies, ateliers, ...)

cartometro.com

If you try and access the original site address using Firefox, you will probably get a Warning message from Google about it being unsafe. Franklin doesn't know what the problem is, but the new address works fine as the site is now with a new host.

 

[edwin_m]

for example the Jubilee Line Extension’s reversing points are London Bridge, Waterloo and Canary Wharf - not exactly the quiet stations!

There's a crossover at Canary Wharf but unless it's changed recently any short turnbacks use the third platform at North Greenwich. That's a much quieter station unless there's an event going on.

 

[bramling]

There's a crossover at Canary Wharf but unless it's changed recently any short turnbacks use the third platform at North Greenwich. That's a much quieter station unless there's an event going on.

I was ignoring North Greenwich as that’s a scheduled reversing point.

However interestingly as regards the original question, I believe it supports the notion that placement of these facilities tends to be coincidental to passenger numbers, as the main reason North Greenwich got the third platform I suspect was because it’s a “box” station so the cost of providing the extra platform was limited to the cost of excavating the extra space (minimal for a box station) and fit out. I have a suspicion it couldn’t have been done so easily at Canary due to the way the station was fitted in a dock. I suspect that if they could have done it narrowing the two main platforms would have been a result.

The North Greenwich reversing works well, although I believe there is an aspiration to minimise or even eliminate it at peak times due to heavy leadings to Stratford. If the Jubilee had enough trains to run as intensely as they would ideally desire then there probably wouldn’t be any North Greenwich reversing at all.

As an aside, the Jubilee has become awkward to operate due to the way nearly all their turn back sidings are now required for the regular service!

 

[edwin_m]

I was ignoring North Greenwich as that’s a scheduled reversing point.

However interestingly as regards the original question, I believe it supports the notion that placement of these facilities tends to be coincidental to passenger numbers, as the main reason North Greenwich got the third platform I suspect was because it’s a “box” station so the cost of providing the extra platform was limited to the cost of excavating the extra space (minimal for a box station) and fit out. I have a suspicion it couldn’t have been done so easily at Canary due to the way the station was fitted in a dock. I suspect that if they could have done it narrowing the two main platforms would have been a result.

The North Greenwich reversing works well, although I believe there is an aspiration to minimise or even eliminate it at peak times due to heavy leadings to Stratford. If the Jubilee had enough trains to run as intensely as they would ideally desire then there probably wouldn’t be any North Greenwich reversing at all.

As an aside, the Jubilee has become awkward to operate due to the way nearly all their turn back sidings are now required for the regular service!

Are turnbacks at Canary Wharf ever done, other than in a fairly dire situation? With reversal having to be in one of two platforms or running tunnels I would have thought blocking one for tipping out and changing ends would cause more trouble than it was worth, especially with the much better facility one stop away.

I assume part of the reason for the third platform being at North Greenwich was to allow extra workings for post-event crowds at the Dome (as it then was). The provision for a never-built branch to Thamesmead may also have had something to do with it, as the Underground preferred to have separate platforms for converging branches, such as Baker Street in the days when the Bakerloo had two branches.

 

[bramling]

Are turnbacks at Canary Wharf ever done, other than in a fairly dire situation? With reversal having to be in one of two platforms or running tunnels I would have thought blocking one for tipping out and changing ends would cause more trouble than it was worth, especially with the much better facility one stop away.

I assume part of the reason for the third platform being at North Greenwich was to allow extra workings for post-event crowds at the Dome (as it then was). The provision for a never-built branch to Thamesmead may also have had something to do with it, as the Underground preferred to have separate platforms for converging branches, such as Baker Street in the days when the Bakerloo had two branches.

Good point about Thamesmead, I’d forgotten about that. Certainly there’s blind tunnels for both directions at the Stratford end of the box (they definitely exist, it’s not an urban myth!). I think that was probably more of the reason than the dome - indeed I seem to recall at the time a big thing was made that North Greenwich station wasn’t designed for the dome but on the contrary the dome came there because of the Jubilee Line.

You’re right Canary isn’t used except during emergency - I think it’s been used occasionally during engineering work. For the latter it’s a better option than North Greenwich as two trains can reverse at the same time - but there’s a catch, which is that North Greenwich is better from a crewing perspective as there’s a depot there. I suspect the crossovers were provided again at least partly opportunistically as there was space at the end of the station “box”.

 

[Dstock7080]

The North Greenwich reversing works well, although I believe there is an aspiration to minimise or even eliminate it at peak times due to heavy leadings to Stratford. If the Jubilee had enough trains to run as intensely as they would ideally desire then there probably wouldn’t be any North Greenwich reversing at all.

The current working timetable in operation before the current emergency has eliminated peak reversing at North Greenwich.