Which crossover has the highest speed limit?

[fgwrich]

IIRC, the 90 mph crossovers at Worting Jn - since replaced by new ones with altered geometry - were installed in 1966 as part of the Basingstoke resignalling for the Bournemouth electrification. The 70 mph crossovers at Hanslope on the WCML were installed in around 1971, replacing the original lower speed junction for Northampton at Roade, a few miles to the North.

Yes, and it now comes with some pretty horrible kinks to boot - particularly if you’re coming down from the flyover and onto the up fast, connecting with the line from Salisbury.

I’m surprised no-one has mentioned Dolphin Junction yet too? Didcot East has of course been mentioned but little east of there.

 

[PGAT]

Stoats Nest Junction is also 70mph I believe

 

[craigybagel]

On the approach to Cardiff there's a 75 mph cross over from the Down Main to the Up Relief, and second from there to the Down Relief (it's bi directional from that point, so trains can use one or both crossovers). I usually aim for less than 70 however; there's a bit of a kick if you take them at line speed.

 

[hexagon789]

The A Stock did upto 70mph but I think some said they had been reduced to 50mph many years before scrapping.

The farewell tour got up to about 74mph I believe but yes, I forget the exact reason they were reduced to 50mph, but ISTR that happened around 2000-or thereabouts.

 

[185]

Searchlight Lane (WCML, north of Stafford, where Stoke & Crewe split on the down slow line) is a proper coffee cup ejecter when you're heading for Stoke

 

[CW2]

With the implosion of Railtrack and the subsequent nervous breakdown, in the early years of Network Rail the maximum speeds of diverging pointwork was 60 mph. The Chief Engineer of NR had formally withdrawn all higher speeds from the catalogue. One of the main elements in Railtrack's implosion was the "Deal of Death" it did with Virgin Trains to upgrade the West Coast Main Line and make it fit for tilting trains. The fallout from all that was that Network Rail inherited the West Coast Route Modernisation programme, closely managed by the DfT (and in particular Stuart Baker of map-making fame). To get the route capacity and journey times to be anywhere near the impossible dreams stitched together by Railtrack and Virgin, it was necessary to go back to first principles and produce designs for 75 mph, 90 mph, and 125 mph turnouts. The design, procurement, installation and commissioning of the 125 mph "split equal"* junction at Rugby Trent Valley Junction was very protracted, but an object of great pride once installed. Thankfully it is a relatively smooth junction, and has worked well ever since installation.
*(125 mph applies only to tilting trains, as explained in an earlier post).

 

[Efini92]

Searchlight Lane (WCML, north of Stafford, where Stoke & Crewe split on the down slow line) is a proper coffee cup ejecter when you're heading for Stoke

XC restrict their services to 80 over the junction for that very reason.

 

[Merle Haggard]

Now here's a thought, I may well be shot down in flames!! But it might apply generally to high speed single lead crossovers.

Travelling from Northampton before and after Hanslope was built, I noticed that trains did seem to be more often checked before crossing at Hanslope compared to when they crossed at Roade.

The Roade crossing was slow speed but a double junction. That meant that in, for example when a train crossed Down fast -> Down Northampton the Up fast was only occupied when the train was actually on the diamond. In the case of Hanslope, however, the much longer single leads together with the (not inconsiderable) distance on the Up Fast between the Down Fast -> Up Fast crossing and the subsequent Up Fast -> Down Northampton one meant that, even with the higher speed, occupation of the Up Fast was for a longer time. In addition, if a Down Northampton was brought to a halt for a train on the Up Fast, when moving off the speed would be no higher than at Roade and resulting in a longer delay than before. It seemed to me that the much greater length of a high speed crossover reduces the chance of a path 'across' without being checked, when trains are on a 4 minute headway in the opposite direction. I did measure the time from the first point to the last when crossing over at full speed, but I can't remember what it was - but it was significant compared to the headway.

As I said, I might be wrong in my thoughts!

Interesting that the latest LNw timetable seems to be based around their up and down trains crossing to / from the fast lines simultaneously, though at Ledburn. That seems elegant, but it means all lines are blocked at once for other traffic and does seem to rely on LNw time keeping perfection.

 

[Whistler40145]

What are the speeds at Colwich Junction?

 

[Efini92]

What are the speeds at Colwich Junction?

 

[dan4291]

Colton South is 70, North is 65mph.

Don't know about Colton South as I don't sign it, but you've definitely got to hold tight over Colton North at 65!

 

[Annetts key]

Not a crossover. But maybe still of interest. Many years ago, the plain single lead points at Cogload Junction were said to be the longest and hence had the highest line speed (100mph on the main, 90mph on the Athelney) on the Western Region.

 

[Merle Haggard]

View attachment 125464

It's interesting that the layout relies on trains already being on the right line (apart from the Up Stafford To Up slow crossover) and this is achieved by true crossovers further South. It's a divergence without points, only crossings, if my understanding of the terms is correct (what the railway modellers call a 'point' is actually a point and a crossing).

Pairing by direction also makes these junctions more straightforward in my view. My recollection is that, on the 4 track bit South of Crewe it was changed at the time of electrification but I'm not sure. It's a pity that the otherwise very useful 'Track Atlas' book doesn't indicate use, direction or reversible working, I just have two concentrate when I'm travelling on the line! It does seem that on the West Coast, pairing is by use (counting via Northampton as the slow line) south of Amerton Jct and by direction to the North, with some bi-directional on the 3 track section just North of Rugby.

If the really busy bit of the W.C.M.L. South of Hanslope was paired by direction it would really make regulation easier! Obviously not practicable now, opportunity lost...

 

[Railsigns]

(what the railway modellers call a 'point' is actually a point and a crossing).

It's actually a pair of points and a (common) crossing.

 

[zwk500]

It's interesting that the layout relies on trains already being on the right line (apart from the Up Stafford To Up slow crossover) and this is achieved by true crossovers further South. It's a divergence without points, only crossings, if my understanding of the terms is correct (what the railway modellers call a 'point' is actually a point and a crossing).

The crossovers are the next signal block, that page only really shows half the junction.

Pairing by direction also makes these junctions more straightforward in my view. My recollection is that, on the 4 track bit South of Crewe it was changed at the time of electrification but I'm not sure. It's a pity that the otherwise very useful 'Track Atlas' book doesn't indicate use, direction or reversible working, I just have two concentrate when I'm travelling on the line! It does seem that on the West Coast, pairing is by use (counting via Northampton as the slow line) south of Amerton Jct and by direction to the North, with some bi-directional on the 3 track section just North of Rugby.

Paired by Use Euston to Rugby, where the flyovers switch it to Paired by direction through to Colwich (apart from the 3-track between Brinklow and Amington). After the 2-track near Colwich it's paired by use again to Crewe, then by direction to Winsford. The 4-track near Wigan and Preston is also paired by use, the only true 4-track paired by direction north of Winsford is Warrington BQ-Winwick Jn.

If the really busy bit of the W.C.M.L. South of Hanslope was paired by direction it would really make regulation easier! Obviously not practicable now, opportunity lost...

It would also make terminating stopping trains harder.

 

[LNW-GW Joint]

There's also the oddity since WCRM of the down fast line being outside the slow between Rugby-Brinklow and around Hartford Jn, where the rebuilt slow lines have become the fast.
From what I gather, the HS2 junction at Handsacre will be with the "slow" TV lines, although all four TV4 tracks are 110/125EPS.
Apparently the SRA did give some thought to making Milford-Stafford-Crewe paired by direction during WCRM, but baulked at the implications that would impose on the layout at Crewe.
Golborne-Wigan is another awkward layout, paired by use but with an slow line underpass at Bamfurlong.
Wigan NW itself is badly aligned with very slow turnouts to/from the 2-track main line further north.

 

[Merle Haggard]

The crossovers are the next signal block, that page only really shows half the junction.

Paired by Use Euston to Rugby, where the flyovers switch it to Paired by direction through to Colwich (apart from the 3-track between Brinklow and Amington). After the 2-track near Colwich it's paired by use again to Crewe, then by direction to Winsford. The 4-track near Wigan and Preston is also paired by use, the only true 4-track paired by direction north of Winsford is Warrington BQ-Winwick Jn.

It would also make terminating stopping trains harder.

Thanks for all that, very informative.

I did appreciate that the crossings were just off the map to the South, just thinking that the actual diverging point is quite simple; not like the old junctions that coped for every combination at one spot, double slips within double junctions and very impressive (and, as serious mishaps showed, confusing) semaphore signals. A lot more efficient for train running nowadays, no longer crashing over all those imperfectly aligned, cant-less p&cs at 20, and the whole junction doesn't fall down if there's just one crucial points failure.

I hadn't appreciated the reversing stoppers problem, which on that part of the W.C.M.L. would be very relevant. A big factor was the L&NW just added the slow lines (initially just one, later even interlaced through Watford tunnel before complete quadrificatioin) by laying alongside the existing route so that was uninterrupted and that's how it's stayed.

 

[jfollows]

It's interesting that the layout relies on trains already being on the right line (apart from the Up Stafford To Up slow crossover) and this is achieved by true crossovers further South. It's a divergence without points, only crossings, if my understanding of the terms is correct (what the railway modellers call a 'point' is actually a point and a crossing).

Pairing by direction also makes these junctions more straightforward in my view. My recollection is that, on the 4 track bit South of Crewe it was changed at the time of electrification but I'm not sure. It's a pity that the otherwise very useful 'Track Atlas' book doesn't indicate use, direction or reversible working, I just have two concentrate when I'm travelling on the line! It does seem that on the West Coast, pairing is by use (counting via Northampton as the slow line) south of Amerton Jct and by direction to the North, with some bi-directional on the 3 track section just North of Rugby.

If the really busy bit of the W.C.M.L. South of Hanslope was paired by direction it would really make regulation easier! Obviously not practicable now, opportunity lost...

Layout post electrification, then post WCML upgrade (following the four-tracking from Tamworth to Armitage) more recently, both at #5 if you're interested. Post electrification the down fast was on the left side of the formation from Armitage to Colwich.

 

[Big Jumby 74]

Yes, and it now comes with some pretty horrible kinks to boot

Rings bells with me, as far back as the early 80's. Was riding shotgun on 33048 on a Poole to LM service, and being a type 3, horses were not being spared coming down off Battledown on to the USL, and it was quite surprising how 'one' was thrown about the cab on hitting those points. No doubt a much smoother ride was had on type 4's!

Edited: I should add, authorisation was in place (for riding s-gun) on the date/train concerned, and speed was within line limits/location etc., but I stand by the rough ride nature that was encountered across Worting Junction. The very fact I noted it at the time, with a view to reporting same to Control, is why I still have my notes relating to same.

 

[zwk500]

I hadn't appreciated the reversing stoppers problem, which on that part of the W.C.M.L. would be very relevant. A big factor was the L&NW just added the slow lines (initially just one, later even interlaced through Watford tunnel before complete quadrificatioin) by laying alongside the existing route so that was uninterrupted and that's how it's stayed.

Paired by use also has the advantage that junctions can be made simpler, as you only need a double junction on one side. The Victoria-East Croydon section shows this quite nicely. It can make it easier to organise traffic rather than all the flyovers as the ECML and SWML use.
Although yes, the practical arrangements for building the extra tracks usually determine the choice.

 

[Merle Haggard]

Layout post electrification, then post WCML upgrade (following the four-tracking from Tamworth to Armitage) more recently, both at #5 if you're interested. Post electrification the down fast was on the left side of the formation from Armitage to Colwich.

Thanks for the link; I have been following the thread but somehow missed that post.

As far as the Colwich mishap, the report mentioned a second, unauthorised person in the cab of the Down train and (as with many of the accident reports of the B.R. period) the significance is not set out but perhaps one is left to 'join the dots'. I expect that many railway people knew people who were passengers on both trains, I'm sure I'm not alone.

Paired by use also has the advantage that junctions can be made simpler, as you only need a double junction on one side. The Victoria-East Croydon section shows this quite nicely. It can make it easier to organise traffic rather than all the flyovers as the ECML and SWML use.
Although yes, the practical arrangements for building the extra tracks usually determine the choice.

Another advantage of pairing by use is that you don't need platforms on the fast line at stations with only a stopping service. The centre islands at some stations at the South end of the West Coast have very elaborate fencing and gates to stop access from the Down slow platform to the Up fast.

 

[The Planner]

Another advantage of pairing by use is that you don't need platforms on the fast line at stations with only a stopping service. The centre islands at some stations at the South end of the West Coast have very elaborate fencing and gates to stop access from the Down slow platform to the Up fast.

Pairing by use makes two track railways for engineering work harder as you need bi-directional signalling as per the Trent Valley.

 

[zwk500]

Another advantage of pairing by use is that you don't need platforms on the fast line at stations with only a stopping service. The centre islands at some stations at the South end of the West Coast have very elaborate fencing and gates to stop access from the Down slow platform to the Up fast.

Tbf it's perfectly possible to not build FL platforms when paired by use, with just an island between the slow lines. Platforms are generally provided on the FL for emergency use or during engineering works but there's nothing stopping them leaving them out.

Pairing by use makes two track railways for engineering work harder as you need bi-directional signalling as per the Trent Valley.

Paired by direction (parallel running), surely? Alternate running in Paired by Use makes 2-tracks easier, I'd have thought.

 

[D6130]

As far as the Colwich mishap, the report mentioned a second, unauthorised person in the cab of the Down train and (as with many of the accident reports of the B.R. period) the significance is not set out but perhaps one is left to 'join the dots'. I expect that many railway people knew people who were passengers on both trains, I'm sure I'm not alone.

I am aware of identity of the unauthorised person in the cab of the down train - it was an off-duty footplateman. I'm not going to name any names as they are probably still alive, although no longer working on the railway. Having spoken to them some time after the accident, I can categorically state that their presence did not contribute to the accident. If it had, that would have been stated prominently in the report. The sole cause of the accident was the Manchester driver's misinterpretation of the very badly-written rules for the then recently-introduced flashing aspect signalling sequence approaching high-speed junctions. Peter Rayner - then Regional Operations Manager for the London Midland Region - was on the scene 50 minutes after the accident and interviewed the driver of the Manchester train in the presence of a senior BT Police officer. I quote from his book of remniscences "On and Off the Rails", which is an excellent read if you can get hold of a copy.

Driver **** told me in the space of a few minutes what his belief and perception of the signalling was and at no time during that interview, nor in the next six months which I spent from time to time in his company, did he attempt to lie to me or tell me other than the truth. I won't go into the detail of the Colwich accident now, but I knew the cause and I knew that we, the railway, had led an honest man into a trap and that within our arrangements for signals showing flashing double yellow lights, there were issues that we should look at with some considerable care.

 

[Merle Haggard]

I am aware of identity of the unauthorised person in the cab of the down train - it was an off-duty footplateman. I'm not going to name any names as they are probably still alive, although no longer working on the railway. Having spoken to them some time after the accident, I can categorically state that their presence did not contribute to the accident. If it had, that would have been stated prominently in the report. The sole cause of the accident was the Manchester driver's misinterpretation of the very badly-written rules for the then recently-introduced flashing aspect signalling sequence approaching high-speed junctions. Peter Rayner - then Regional Operations Manager for the London Midland Region - was on the scene 50 minutes after the accident and interviewed the driver of the Manchester train in the presence of a senior BT Police officer. I quote from his book of remniscences "On and Off the Rails", which is an excellent read if you can get hold of a copy.

Driver **** told me in the space of a few minutes what his belief and perception of the signalling was and at no time during that interview, nor in the next six months which I spent from time to time in his company, did he attempt to lie to me or tell me other than the truth. I won't go into the detail of the Colwich accident now, but I knew the cause and I knew that we, the railway, had led an honest man into a trap and that within our arrangements for signals showing flashing double yellow lights, there were issues that we should look at with some considerable care.

Thanks.

The doubt raised in my mind by the wording of the report was whether the person was really a trainee footplateman or just someone who gave that impression to the driver, working elsewhere on the railway.

I do have the book but I unfortunately didn't recall that particular section.

 

[D6130]

The doubt raised in my mind by the wording of the report was whether the person was really a trainee footplateman or just someone who gave that impression to the driver, working elsewhere on the railway.

He was a secondman/driver's assistant working elsewhere on the railway....and still in uniform after finishing his shift.

I do have the book but I unfortunately didn't recall that particular section.

Pages 340-343.

 

[Shimbleshanks]

Stoats Nest Junction is also 70mph I believe

It had a TSR to 60mph for years though; not sure if it's since been lifted.

 

[The Planner]

Paired by direction (parallel running), surely? Alternate running in Paired by Use makes 2-tracks easier, I'd have thought.

Yes, that's what I meant.

 

[civ-eng-jim]

Can any active perway operatives help out us old retirees by adding what euipment is used at these speeds, eg F24 or G28 or even split G28? (Probably old method of describing P&C in this modern world)

NR60 Mk2 H (32.365 - 34.5. Not sure on the Xing angle adopted) was being developed a few years back

 

[Bald Rick]

Can any active perway operatives help out us old retirees by adding what euipment is used at these speeds, eg F24 or G28 or even split G28? (Probably old method of describing P&C in this modern world)

H switches have been in use for a while.

Interesting that the latest LNw timetable seems to be based around their up and down trains crossing to / from the fast lines simultaneously, though at Ledburn. That seems elegant, but it means all lines are blocked at once for other traffic and does seem to rely on LNw time keeping perfection.

Whilst the lines are blocked for other traffic during te time of the crossing movements, that’s fine as the trains crossing need paths on both Fast and Slow lines, therefore by definition there can be nothing else around, by plan or otherwise!