How long is too long for an absolute block section and where is the longest?

[507020]

Burscough Bridge works TCB to Sandhills - it's not an absolute block section.

I am aware that there must be some sort of connection between Burscough Bridge box and Sandhills because the BB1 and BB2 signals show on the map on Open Train Times. Beyond there are semaphores at Parbold which has no electronic connection to anywhere. Real time trains always shows no report.

when they were rebuilding the WCML for electrification in the 60's, it was said (in jest) trains were signalled county to county rather than block to block!

As in the train is now entering Staffordshire? Would this system have had to have been changed on the creation of the Metropolitan counties in 1974? Additional blocks would have been needed for the West Midlands, Greater Manchester and Merseyside.

Cost of opening an extra signal box vs. resignalling vs. paying out if the cause is determined to be Network Rail…
Guess which wins…

So yes, the length is determined by the planned / required line capacity.

If Network Rail is repeatedly paying out for delays then that must improve the business case for resignalling mustn’t it?

At the risk of kicking the hornets nest here - With modern technology surely there's a better solution?

I believe it’s called ETCS. Correct me if I’m wrong but does ETCS work by determining what a train’s stopping distance will be at the speed it’s travelling at and marking that distance immediately in front of it as occupied, without defined blocks, hence moving block? I can’t help thinking that instead of the European interoperability of obsolete 25 year old GSM technology, we should be developing a new British signalling system fit for the 21st century.

How much resilliance do you factor in, where do you stop, at what point does the cost outweigh the benefits?

The short answer would be “enough”. What is the most common/average length of blocks across the network. There must be a certain level which is sufficient for most lines. 7 mile or longer sections are edge cases and should really be eliminated due to their instability. Other edge cases include running 24tph on Thameslink.

Thats a business decision, surely. A massive delay because of a long section means the railway suffers reputational loss. How you calculate the value of that I dont know.

A very good point.

Are there any single track sections longer than that? Some on the Far North line look to be close to 20 miles.

Again, completely ridiculous. That equals the one on the Bentham line.

Yes it is unsafe as allowing another train into an absolute block section contravenes the fundamental rule of absolute block: one train in one section at one time!
Where the signals are placed though is a different question and there quite possibly are better places for signals to assist with keeping the passenger service running. There is always the option of adding intermediate block signals to sub divide a section, but the cost of that would have to be weighed against the cost of delays/or benefits that splitting the section can bring in purely financial terms.

I am aware of the fundamentals of railway signalling. I am not suggesting that it is safe for a train to proceed into an occupied block under any circumstances.

Do you know the previous train is 7 miles away, or do you suspect it is based on what normally happens? That's how absolute block works - you don't send the next train into the section until the previous one has left. The signallers have no visibility on what's going on until the train reaches them. You resignal if you need more visibility and/or increased frequency.

While it IS safe to proceed if the next train IS actually 7 miles away, of course all signalling only exists because without it, it is not KNOWN if the train IS 7 miles away or 7 feet away (the ML148 signal is on a curve surrounded by trees). The issue of frequency is that inability to differentiate between 7 miles and 7 feet is insufficient for most purposes.

It is nowadays ! (Or at least was pre-Covid). The Far North Line service is more intense now than ever, with as well as the four Wick/Thurso through trains, various short workings. It got to the stage that if the afternoon northbound Wick was late, it would be held for around an hour to avoid delaying the afternoon southbound Wick, because if the latter was late, its crossings with other trains, conflict with the Kyle line trains, and turnround times would wreck the Far North and Kyle line timetable for the rest of the day; Whereas the northbound caused no such issues.

I am confused by Far North line frequencies. As far as I can tell, I don’t believe it’s possible to use the Far North line to visit Thurso/Wick/John O’Groats in a day from anywhere out of Glasgow/Edinburgh/Aberdeen/Inverness and then return that same evening, necessitating at least an overnight stay at the northernmost tip of Great Britain.

Pre Covid trains crossed there every morning.

Sometimes even resignalling isn't the answer. When Nantwich - Shrewsbury was resignalled in 2013, it went from Absolute Block to TCB controlled from Cardiff - but the old AB sections were replicated, meaning there is still a near 10 mile section between Prees and Wrenbury which limits how close the local service can follow the fast, and adds to delays when trains are running late.

There was a box half way along that section at Whitchurch, but it closed a few years before resignalling, and the opportunity to replace it wasn't taken up.

That is quite clearly another example of where the level of resiliency is insufficient even for the current service. Should modern resignalling projects not also include provision for future frequency increases?

The Southport line has another long absolute block section from Parbold to just before Wigan sidings. Unless both are resignalled, the train wll just end up waiting at Parbold anyway.

The long block sections can cause problems at peak times, when 3 trains an hour use the line as one delay causes a knock on, add in the railhead treatment train that often runs in the afternoon peak during leaffall and delays can mount, whether or not it's worth the cost of resignalling, I'm not sure.

I was thinking about that. That probably explains why the 2tph to Southport run within 15-20 minutes of each other, the minimum permissible by the long sections, but leaving a spare path for a sandite/de-icer MPV in winter in the spare 40-45 minutes.

Interestingly, if the Burscough Curves are to reopen, Southport to Burscough Bridge is going to need to be resignalled to allow about 8tph, including resiliency/railhead treatment and be integrated with the Ormskirk to Preston line which currently lacks any signalling equipment at all. The resignalling could be done out of the budget for that project as a whole.

 

[scrapy]

Interestingly, if the Burscough Curves are to reopen, Southport to Burscough Bridge is going to need to be resignalled to allow about 8tph, including resiliency/railhead treatment and be integrated with the Ormskirk to Preston line which currently lacks any signalling equipment at all. The resignalling could be done out of the budget for that project as a whole.

Even if Burscough Bridge station area were to be resignalled there's no guarantee that the block section would be altered, although certainly possible especially as it's likely it would be combined with box closures.

I very much doubt there would be demand for more than one train an hour from Ormskirk or Preston (they may even be combined), or the paths at Preston to facilitate more than this. 8tph or even 6tph with contingency just won't happen.

 

[507020]

Even if Burscough Bridge station area were to be resignalled there's no guarantee that the block section would be altered, although certainly possible especially as it's likely it would be combined with box closures.

I very much doubt there would be demand for more than one train an hour from Ormskirk or Preston (they may even be combined), or the paths at Preston to facilitate more than this. 8tph or even 6tph with contingency just won't happen.

These 6tph would be 2tph Southport - Manchester as now, 2tph Southport - Ormskirk and 2tph Southport - Preston. Contingency requires 8tph signalling capacity, splitting the 7 mile long block into at least 8 pieces each roughly 7/8 of a mile long. In the event there is only 1tph to Ormskirk and Preston then this would be reduced to 6tph capacity. I would hope there would also continue to be a direct Ormskirk - Preston service. Whether or not this would happen though I can’t tell.

 

[XAM2175]

when they were rebuilding the WCML for electrification in the 60's, it was said (in jest) trains were signalled county to county rather than block to block!

As in the train is now entering Staffordshire? Would this system have had to have been changed on the creation of the Metropolitan counties in 1974? Additional blocks would have been needed for the West Midlands, Greater Manchester and Merseyside.

"In jest" meaning "jokingly" meaning "it was a joke".

I believe it’s called ETCS. Correct me if I’m wrong but does ETCS work by determining what a train’s stopping distance will be at the speed it’s travelling at and marking that distance immediately in front of it as occupied, without defined blocks, hence moving block? I can’t help thinking that instead of the European interoperability of obsolete 25 year old GSM technology, we should be developing a new British signalling system fit for the 21st century.

The new signalling system fit for the 21st century is ETCS. Are you objecting to it purely on nationalistic grounds?
(and as an aside, moving block control is provided for only in ETCS Level 3, the highest level of train control that system provides)

I am confused by Far North line frequencies. As far as I can tell, I don’t believe it’s possible to use the Far North line to visit Thurso/Wick/John O’Groats in a day from anywhere out of Glasgow/Edinburgh/Aberdeen/Inverness and then return that same evening, necessitating at least an overnight stay at the northernmost tip of Great Britain.

Is it a problem that it's the northernmost tip of Great Britain?

 

[507020]

"In jest" meaning "jokingly" meaning "it was a joke".

I also meant this as a joke but now feel I didn’t make that clear enough.

The new signalling system fit for the 21st century is ETCS. Are you objecting to it purely on nationalistic grounds?
(and as an aside, moving block control is provided for only in ETCS Level 3, the highest level of train control that system provides)

I am objecting to it on grounds that it is 20th century technology and now obsolete. The radio components of ETCS including GSM-R are based on obsolete GSM aka 2G or 2nd generation mobile phone networks from the 1990s. The South Korean railways use a superior 4th generation LTE-R system but this is still obsolete as we are now on to 5G. ETCS also lacks certain UK specific features that could generate revenue e.g. steam railtours now banned from the Cambrian line due to steam ETCS operation being impossible. Technological reasons must come before nationalistic tendencies.

Is it a problem that it's the northernmost tip of Great Britain?

The problem with it being at the northernmost tip of Great Britain is it’s distance from the rest of Great Britain. Of course that is the main reason to visit. London also experiences the same problem being at effectively the southeastern most tip of Great Britain.

As demonstrated by Gareth Dennis on his Railnatter episode 65, the populations of Thurso and Wick alone (excluding any tourism potential) justify a rail link to the rest of Scotland and Great Britain regardless of distance. I would very much like to take a trip on the Far North line but have been so far unable to plan one due to the journey time and frequency necessitating an overnight stay. This would negate any attempt of mine to stay in Edinburgh or Aberdeen for a week as I would be forced to move hotels etc if I chose to visit John O’Groats, something I very much intend to do.

 

[XAM2175]

I also meant this as a joke but now feel I didn’t make that clear enough.

Quite.

I am objecting to it on grounds that it is 20th century technology and now obsolete. The radio components of ETCS including GSM-R are based on obsolete GSM aka 2G or 2nd generation mobile phone networks from the 1990s. The South Korean railways use a superior 4th generation LTE-R system but this is still obsolete as we are now on to 5G.

GSM-R suppliers have given undertakings to support GSM-R products and technologies until 2030 at the earliest, and the UIC is currently working on a 5G-derived successor system (under the working name Future Railway Mobile Communication System). There will be a clear upgrade path to this successor system for all GSM-R users, including those who are reliant on it for ETCS operations.

ETCS also lacks certain UK specific features that could generate revenue e.g. steam railtours now banned from the Cambrian line due to steam ETCS operation being impossible.

This is totally incorrect. For a start; operation with heritage stock is not a "UK specific" [sic] feature - other European countries also have active preservation movements. Secondly; ETCS operation with steam is not "impossible" - it is simply not yet done in Britain. I suspect you will find that this situation changes in the not-too-distant future when ETCS Level 2 operation (the same level as is in use on the Cambrian) is implemented at the southern end of the East Coast Main Line.

Technological reasons must come before nationalistic tendencies.

I'm glad you recognise this, because it's the reason that designing "a new British signalling system fit for the 21st century" is unwise. You would be throwing away a vast amount of work and experience in the pursuit of a system that wouldn't be all that different... except that it would also be completely unproven, and quite probably also tied to a very small number of suppliers who would either charge the Treasury like the proverbial wounded bull, or dump the project at the first sign of even minor upheaval. Or both.

And you'd still be reliant on GSM-R, unless you also propose reinventing that wheel too.

The problem with it being at the northernmost tip of Great Britain is it’s distance from the rest of Great Britain. Of course that is the main reason to visit. London also experiences the same problem being at effectively the southeastern most tip of Great Britain.

As demonstrated by Gareth Dennis on his Railnatter episode 65, the populations of Thurso and Wick alone (excluding any tourism potential) justify a rail link to the rest of Scotland and Great Britain regardless of distance. I would very much like to take a trip on the Far North line but have been so far unable to plan one due to the journey time and frequency necessitating an overnight stay. This would negate any attempt of mine to stay in Edinburgh or Aberdeen for a week as I would be forced to move hotels etc if I chose to visit John O’Groats, something I very much intend to do.

I agree that the populations of Thurso and Wick merit decent and reliable connections to the rest of Scotland (which contains the airports I expect most of them would use to get to anywhere south of the Tyne) - but I would suggest that the connections should be designed first and foremost around their needs, which - regrettably - will not necessarily align with those of aspiring tourists from Sefton.

I would further suggest that you would be making a greater contribution to the local economy in Caithness if you did happen to make an overnight stop there.

 

[Annetts key]

I am objecting to it on grounds that it is 20th century technology and now obsolete.

You clearly don’t understand U.K. railway signalling systems. This topic is discussing an Absolute Block section between traditional mechanical signal boxes and you are talking about ETCS as being obsolete!

The railway only changes and upgrades signalling systems when it sees a need to do so and they find the money to do so. Safety and reliability of the signalling systems were both of prime importance in the technology that was used.

The recently resignalled (recontrolled) parts of the GWML with 125MPH trains controlled from TVSC uses SSI track side modules based on those designed originally for the Leamington Spa resignalling scheme. Which is 1980s technology…

So nearly all U.K. railway signalling equipment could be classed as obsolete. That’s what you get when you want tried and tested technology…

 

[norbitonflyer]

I am confused by Far North line frequencies. As far as I can tell, I don’t believe it’s possible to use the Far North line to visit Thurso/Wick/John O’Groats in a day from anywhere out of Glasgow/Edinburgh/Aberdeen/Inverness and then return that same evening, necessitating at least an overnight stay at the northernmost tip of Great Britain.

It's not frequency, but distance, that would make this difficult. In any case, it is possible to do the round trip from London in one day (and two nights).
Euston dep 2115
Inverness arr 0842, dep 1041
Thurso arr 1424,
Wick arr 1456, dep 1600
Inverness arr 2010, dep 2045
Euston 0800

If you want to visit John O Groats, a taxi should be able to take you the 36 miles from Thurso to Wick via JO'G well within the 90 minutes between arrival in Thurso and departure from Wick

 

[LSWR Cavalier]

I It is worth spending a week at Wick or Thurso. What about Georgemas Junction, how long are the three blocks from there? Do trains perform interesting manoeuvres there?
When I went there the trains from the south called at Wick, reversed, terminated at Thurso.

 

[norbitonflyer]

I It is worth spending a week at Wick or Thurso. What about Georgemas Junction, how long are the three blocks from there? Do trains perform interesting manoeuvres there?
When I went there the trains from the south called at Wick, reversed, terminated at Thurso.

When I went there, the train divided at Georgemas Junction, with a Class 26 waiting there to take the Thurso portion. There was no realistic way of getting between Thurso and Wick other than the local bus (or a very long wait at Georgemas).

Yes, it was a very long time ago

 

[Bletchleyite]

I It is worth spending a week at Wick or Thurso. What about Georgemas Junction, how long are the three blocks from there? Do trains perform interesting manoeuvres there?
When I went there the trains from the south called at Wick, reversed, terminated at Thurso.

These days they go Georgemas-reverse-Thurso-reverse-Wick-reverse-Thurso-reverse-Georgemas-reverse-south!

 

[marsker]

Back to the original topic - in the dying days of the Great Central main line, I believe that it was one block section from Leicester Central to Woodford Halse, or maybe, even Culworth Junction, that's in the order of 35 miles. Signal arms had been removed at all the intermediate stations and the boxes closed. I believe that there was another very long block section to the south of Culworth Junction.
I was told by a loco crew that the'd had to get across fields to a farmhouse to report a failure by telephone.

 

[Falcon1200]

Again, completely ridiculous. That equals the one on the Bentham line.

(Regarding 20 mile single line sections on the Far North Line)
Not ridiculous, simply all that is required for the normal level of service.

I am confused by Far North line frequencies. As far as I can tell, I don’t believe it’s possible to use the Far North line to visit Thurso/Wick/John O’Groats in a day from anywhere out of Glasgow/Edinburgh/Aberdeen/Inverness and then return that same evening, necessitating at least an overnight stay at the northernmost tip of Great Britain.

You can indeed 'do' the Far North from Inverness, Aberdeen, Edinburgh or Glasgow in one day, albeit in the latter three cases with not very long in Wick, and not enough time for a worthwhile visit to John O'Groats, but certainly not from anywhere further south. It is worth remembering that the rail distance from Glasgow to Inverness is 180 miles, with Inverness to Wick a further 161 miles.

The only time I travelled the full route was 1979, when it was in some ways more difficult, as no train served both Thurso and Wick, but in others easier, as the overnight Glasgow and Edinburgh/Inverness trains still ran.

To get back on topic, block and single line sections are organised based on the planned level of service; Additional facilities to account for late running are nice but not always justifiable, and it is doubtful whether the delay penalties incurred (only) when trains run late would ever pay for the provision, staffing and maintenance of such.

 

[Meerkat]

Ps John o’Groats is rubbish and not even the real extremity.
Duncansby and Dunnet Heads are much more impressive!

 

[sw1ller]

Pretty long one between Holyhead and Gaerwen. Off the top of my head I think it’s 17 miles.

Ty Croes doesn’t count by the way. Before anyone mentions it.

 

[craigybagel]

Pretty long one between Holyhead and Gaerwen. Off the top of my head I think it’s 17 miles.

Ty Croes doesn’t count by the way. Before anyone mentions it.

No but Valley does 14 ¾ miles between those two.

I'm sure they've been talking about turning Ty Croes into a block post for years, but perhaps they're just waiting for the whole island to get resignalled instead?

 

[ItsGrimUpNorth]

The West Cumbrian line between Wigton and Maryport has a long block section, not sure on exact distance but it’s a good length.

If the mine proposed near Whitehaven goes ahead, then Network Rail want to do something to rectify it’s size as the line would be much busier and such a long section would be counter productive.

There was a 2019 Cumbrian Coast Study by Network Rail which mentions it, it’s easily found via Google.

 

[Watershed]

The West Cumbrian line between Wigton and Maryport has a long block section, not sure on exact distance but it’s a good length.

Just under 16 miles. It takes passenger services approximately 21 minutes to traverse, so given that with Absolute Block timing you need to allow 2 minutes' margin, it effectively means each train occupies the block for 23 minutes at a time. Certainly not the longest block section out there but with a near hourly passenger service it doesn't allow much leeway for delays.

 

[craigybagel]

I think its been said on here before, but that resignalling was a shocker.

Indeed - though I think it may well have been me that said it hopefully lessons have been learned....

 

[sw1ller]

No but Valley does 14 ¾ miles between those two.

I'm sure they've been talking about turning Ty Croes into a block post for years, but perhaps they're just waiting for the whole island to get resignalled instead?

Haha. Oh yeah. Completely forgot about valley. I’ve read just today in the BOP that work on the signals starts in august.

Indeed - though I think it may well have been me that said it hopefully lessons have been learned....

It has been a shocker. Do you know if the bi-di has ever been used? And designing a signal that needs a pilotman to use it is just stupid.

 

[ChiefPlanner]

Yes - but even main lines used to have long sections with intermediate boxes switched out to save money - viz St Albans (South) used to work to Mill Hill overnight on Saturdays / Sunday am - as Napsbury , Radlett and Elstree had gone to bed . Doubtless many others.

One has to say that the cost effective resignalling on the HoW and especially the Cambrian undoubtedly helped save those lines in the bad days of the 1980's and before - Hendy to Craven Arms under one signalman is impressive -let alone a couple of people at Machynlleth doing Pwllheli / Aberystwyth to Sutton Bridge Junction. Ditto the Scottish examples.

Slightly off topic I know - but ERTMS is not the affordable answer to everything.

 

[Bald Rick]

I am objecting to it on grounds that it is 20th century technology and now obsolete. The radio components of ETCS including GSM-R are based on obsolete GSM aka 2G or 2nd generation mobile phone networks from the 1990s.

On a point of order, ETCS doesn’t have GSM-R. ETCS is purely the signalling component of ERTMS, which uses GSM-R as the carrier. GSM-R can be replaced (as is proposed) whilst ETCS stays as it is.

 

[InOban]

Quite.


GSM-R suppliers have given undertakings to support GSM-R products and technologies until 2030 at the earliest, and the UIC is currently working on a 5G-derived successor system (under the working name Future Railway Mobile Communication System). There will be a clear upgrade path to this successor system for all GSM-R users, including those who are reliant on it for ETCS operations.


This is totally incorrect. For a start; operation with heritage stock is not a "UK specific" [sic] feature - other European countries also have active preservation movements. Secondly; ETCS operation with steam is not "impossible" - it is simply not yet done in Britain. I suspect you will find that this situation changes in the not-too-distant future when ETCS Level 2 operation (the same level as is in use on the Cambrian) is implemented at the southern end of the East Coast Main Line.


I'm glad you recognise this, because it's the reason that designing "a new British signalling system fit for the 21st century" is unwise. You would be throwing away a vast amount of work and experience in the pursuit of a system that wouldn't be all that different... except that it would also be completely unproven, and quite probably also tied to a very small number of suppliers who would either charge the Treasury like the proverbial wounded bull, or dump the project at the first sign of even minor upheaval. Or both.

And you'd still be reliant on GSM-R, unless you also propose reinventing that wheel too.


I agree that the populations of Thurso and Wick merit decent and reliable connections to the rest of Scotland (which contains the airports I expect most of them would use to get to anywhere south of the Tyne) - but I would suggest that the connections should be designed first and foremost around their needs, which - regrettably - will not necessarily align with those of aspiring tourists from Sefton.

I would further suggest that you would be making a greater contribution to the local economy in Caithness if you did happen to make an overnight stop there.

The fact that we have 3g, 4g, and in some places 5g doesn't make 2g obsolete. It is perfectly adequate for the rate of data transfer required. Even the mobile masts will locate the train to within a mile or two. It's high time that signalling on secondary lines moved out of the 19th century.

 

[craigybagel]

It has been a shocker. Do you know if the bi-di has ever been used? And designing a signal that needs a pilotman to use it is just stupid.

I've used it myself! But only from Prees back to the crossover at Wem (the signalling had failed at Crewe and there was a queue of trains in front of us so we were sent back to Salop). It's been used a few times when trains or signals have failed and units need turning. I'm not aware of anything ever going bang road all the way to Salop and needing the pilotman to get into the station though.

 

[RT4038]

Back to the original topic - in the dying days of the Great Central main line, I believe that it was one block section from Leicester Central to Woodford Halse, or maybe, even Culworth Junction, that's in the order of 35 miles. Signal arms had been removed at all the intermediate stations and the boxes closed. I believe that there was another very long block section to the south of Culworth Junction.
I was told by a loco crew that the'd had to get across fields to a farmhouse to report a failure by telephone.

I don't think this is can be quite right. Rugby Central signalbox was operational right up to the last day in 1969 when the residual Nottingham (Arkwright Street) - Rugby (Central) trains finished.

A glance in the 1964/5 timetable shows the 10.22pm York-Swindon / 2.18am from Leicester Central arrived Woodford 3.10am and passed Culworth Junction about 3.15am, whilst the 11.5pm Manchester Central-Marylebone departed Leicester Central at 3.0am. In the reverse direction the 9.55pm Marylebone-Manchester departed Woodford 11.58pm and was due in Leicester at 12.36am. Closely following was the 9.50pm Swindon-York due away from Woodford at 12.17am. So an intermediate box, most likely Rugby Station, must have been open to permit such a timetable. Rugby Station box was also required in the morning and evening to turn/stable local trains to & from Nottingham.

 

[geoffk]

When I lived in Worcester, the section between Droitwich Spa and Worcester Tunnel Junction (5 miles 18 chains according to RTT) was one block section, not as long as some mentioned above but a busier section of line. At some time since 2003, a new Intermediate Block signal was put in just north of the former Fernhill Heath station site. This must be the signal referred to as Droitwich Signal 68 on RTT but it appears to be only in the Worcester-bound direction.

 

[Pigeon]

Yes. Up side only, between Infernal Heath ex-station and the first overbridge north of it, with the distant between that bridge and the next one. (Also, Droitwich down home is now a colour light.)

IME it was pretty rare to ever get held at Droitwich going north, but not that uncommon to be held outside the north end of Worcester tunnel waiting for something else to finish messing about on the single line sections, especially the one through Foregate Street, or at Tunnel Junction going north, waiting for something to cross in front coming the other way. I guess now there are more trains on the route those checks have attained greater significance so it's an advantage to not have the section approaching TJ so long.

At any rate, it makes an interesting example of a section where "how long is too long" depends on which way you're going (for reasons other than obvious gradienty ones).

 

[Gloster]

The really long section working between boxes tended to be on Saturday night and early on Sunday. There were pretty well no goods, parcels or mail trains, but some lines would remain open for night trains, sometimes only one in each direction. If there was no engineering work, then just about every box with a switch would be closed, but those without a switch (and sometimes others for some specific reason) would have to stay open if the line was to remain open to traffic.

 

[Ianno87]

How long is too long?

Depends how many trains you want to run.

 

[507020]

GSM-R suppliers have given undertakings to support GSM-R products and technologies until 2030 at the earliest, and the UIC is currently working on a 5G-derived successor system (under the working name Future Railway Mobile Communication System). There will be a clear upgrade path to this successor system for all GSM-R users, including those who are reliant on it for ETCS operations.

This is very good to hear, 2030 being well into the 21st century, with GSM-R nearing 40 years old at this point.

other European countries also have active preservation movements. I suspect you will find that this situation changes in the not-too-distant future when ETCS Level 2 operation is implemented at the southern end of the East Coast Main Line.

How long will it be before this is completed? Are all trains which regularly run on the southern end of the ECML now fitted with ETCS Level 2? The problem of steam with ETCS seems more likely to be solved when a substantial majority of lines are equipped for ETCS.

I'm glad you recognise this, because it's the reason that designing "a new British signalling system fit for the 21st century" is unwise. You would be throwing away a vast amount of work and experience in the pursuit of a system that wouldn't be all that different... except that it would also be completely unproven, and quite probably also tied to a very small number of suppliers who would either charge the Treasury like the proverbial wounded bull, or dump the project at the first sign of even minor upheaval. Or both.

And you'd still be reliant on GSM-R, unless you also propose reinventing that wheel too.

It is now a proven technology internationally, but rather than adopting European interoperability in the first place, I do believe it would have been a better solution to have designed, entirely in house of course, “a new British signalling system fit for the 21st century” that didn’t necessitate ripping out all of the existing signalling infrastructure in the whole country at some point in order to implement the changes. ETCS, while it is now the future, draws no lineage from what is already in place in much of Great Britain, which makes it all that harder to implement.

I agree that the populations of Thurso and Wick merit decent and reliable connections to the rest of Scotland (which contains the airports I expect most of them would use to get to anywhere south of the Tyne) - but I would suggest that the connections should be designed first and foremost around their needs, which - regrettably - will not necessarily align with those of aspiring tourists from Sefton.

I would further suggest that you would be making a greater contribution to the local economy in Caithness if you did happen to make an overnight stop there.

*from Southport.

I strongly believe that all railways should primarily be there to cater for the local residents, who’s homes they serve. Unfortunately, Southport is a good example of a place where it’s rail services are designed to cater more for people from Liverpool and Manchester coming into Southport, rather than people who live in Southport travelling to places they want to get to, either locally or long distance. The quality of the Merseyrail service being equal in both directions, getting to Liverpool is not a problem, although getting to Lime Street adds an hour onto any long journeys, but the direct services from Stalybridge and Alderley Edge are much more use for people travelling from extremities of Greater Manchester to visit Southport, than anyone from Southport wanting to get to Manchester Airport for example.

At least one overnight stop in Caithness is the most likely outcome of my journey on the Far North line in the future.

You clearly don’t understand U.K. railway signalling systems. This topic is discussing an Absolute Block section between traditional mechanical signal boxes and you are talking about ETCS as being obsolete!

The railway only changes and upgrades signalling systems when it sees a need to do so and they find the money to do so. Safety and reliability of the signalling systems were both of prime importance in the technology that was used.

The recently resignalled (recontrolled) parts of the GWML with 125MPH trains controlled from TVSC uses SSI track side modules based on those designed originally for the Leamington Spa resignalling scheme. Which is 1980s technology…

So nearly all U.K. railway signalling equipment could be classed as obsolete. That’s what you get when you want tried and tested technology…

I think there is a general consensus that these long signalling sections originated from closures of intermediate boxes in the days of Absolute Block, with several adjacent sections being merged into a single unreasonably large one, whether this section is now still worked by Absolute Block or not.

The original mechanical signal boxes of the 19th century are the definition of tried and tested technology, while GSM-R counts as tried and tested now, it will start showing it’s age sooner or later. I have no trust that 20th century technologies such as GSM-R will survive anywhere near long enough to be approaching 200 years old. The concept of Solid State Interlocking likely will in some evolved form and a version of ETCS carried by a more modern radio system is likely the way forward.

I believe the British Rail Research Department of the 1970s and 80s was by far the greatest loss of privatisation. One of its aims was to develop new technology which maintained compatibility with what was already in situ, something ETCS can’t do. Surely the best way forward for some lines will be to move directly from the 19th century to the 21st century and it’s 5G ETCS, with no intermediate step of obsolescence.

It's not frequency, but distance, that would make this difficult. In any case, it is possible to do the round trip from London in one day (and two nights).
Euston dep 2115
Inverness arr 0842, dep 1041
Thurso arr 1424,
Wick arr 1456, dep 1600
Inverness arr 2010, dep 2045
Euston 0800

If you want to visit John O Groats, a taxi should be able to take you the 36 miles from Thurso to Wick via JO'G well within the 90 minutes between arrival in Thurso and departure from Wick

Of course I will not be starting at Euston, I will be starting at Southport, so any detour via Euston will effectively double the journey time. London is over 30 miles further away from here than Edinburgh!

When I went there, the train divided at Georgemas Junction, with a Class 26 waiting there to take the Thurso portion. There was no realistic way of getting between Thurso and Wick other than the local bus (or a very long wait at Georgemas).

Yes, it was a very long time ago

Surely a direct local service between Thurso and Wick with a reasonable journey time, which doesn’t even require any reversals as the junction is facing the right way, is the pinnacle of the Far North line being for the residents of Thurso, Wick and Georgemas Junction, above the service to the rest of Scotland taking several hours.

These days they go Georgemas-reverse-Thurso-reverse-Wick-reverse-Thurso-reverse-Georgemas-reverse-south!

Akin to the Glossip-Hadfield-Glossop services on what’s left of the Woodhead Line.

Back to the original topic - in the dying days of the Great Central main line, I believe that it was one block section from Leicester Central to Woodford Halse, or maybe, even Culworth Junction, that's in the order of 35 miles. Signal arms had been removed at all the intermediate stations and the boxes closed. I believe that there was another very long block section to the south of Culworth Junction.
I was told by a loco crew that the'd had to get across fields to a farmhouse to report a failure by telephone.

Would you say this counts as unreasonably/ridiculously/too long if the driver couldn’t even get to a telephone? This of course highlights the importance of GSM-R today. Any failure caused by the system’s age could result in the same situation.

You can indeed 'do' the Far North from Inverness, Aberdeen, Edinburgh or Glasgow in one day, albeit in the latter three cases with not very long in Wick, and not enough time for a worthwhile visit to John O'Groats, but certainly not from anywhere further south. It is worth remembering that the rail distance from Glasgow to Inverness is 180 miles, with Inverness to Wick a further 161 miles.

The only time I travelled the full route was 1979, when it was in some ways more difficult, as no train served both Thurso and Wick, but in others easier, as the overnight Glasgow and Edinburgh/Inverness trains still ran.

To get back on topic, block and single line sections are organised based on the planned level of service; Additional facilities to account for late running are nice but not always justifiable, and it is doubtful whether the delay penalties incurred (only) when trains run late would ever pay for the provision, staffing and maintenance of such.

I would only consider a worthwhile journey. What about the lost revenue from passengers who refuse to travel by train again when their trains are frequently delayed because of infrastructure constraints?

Ps John o’Groats is rubbish and not even the real extremity.
Duncansby and Dunnet Heads are much more impressive!

Just like the Lizard is better than Land’s End and it’s rampant commercialism. Any idea how to get to Duncansby and Dunnet Heads?