Tilting

[Bald Rick]

Will the arrival of GSM(r) and possible thing like ETCS Level 2 make tilting cheaper to implement?

Yes, but not perhaps in the way you think.

Stating the obvious, tilt is used purely to increase linespeeds. To do that you have to check the (almost) 100 factors that can affect linespeed, and do work on any of them where required. Some of these relate to signalling, eg signal sighting and signal spacing, and these are more easily resolved with ETCS L2 than with conventional signalling.

The ETCS balises could be doubled up as a TASS balise if their positions were coincident, but frankly the cost of a balise is next to nothing in the wider context.

 

[Carlisle]

With regards to the tilting section between Banbury and Oxford. There was never any speed differential for tilt or non tilt unlike some sections between Stoke and Macclesfield for example. So there was no timing benefit to the tilting section. It was more about being used as a proving ground

Yes I think there were two initial proving grounds set up around 2002 Oxford -Banbury and Carnforth-Carlisle

 

[Muzer]

Yes, but not perhaps in the way you think.

Stating the obvious, tilt is used purely to increase linespeeds. To do that you have to check the (almost) 100 factors that can affect linespeed, and do work on any of them where required. Some of these relate to signalling, eg signal sighting and signal spacing, and these are more easily resolved with ETCS L2 than with conventional signalling.

The ETCS balises could be doubled up as a TASS balise if their positions were coincident, but frankly the cost of a balise is next to nothing in the wider context.

IIRC TASS basically uses the "user defined extension" message type for ETCS, right? So yeah, presumably ETCS balises would work fine.

 

[thenorthern]

I think there were plans to install in cab signalling on the WCML to allow trains to reach 140 but Network Rail decided against it because of cost.

What was the first Virgin Trains route to use Pendolinos? I can't remember if it was London to Manchester via Crewe or London to Birmingham. I think London to Glasgow was last.

 

[Manchester77]

Think it was the manchester services in time for the 2002 commonwealth games

 

[Domh245]

For some reason, I think that those initial services were run without TASS because it hadn't been fully installed yet, so it was essentially a new train running at old speeds, but I may be wrong, and am interested to find out if this was the case

 

[edwin_m]

HS2 have already talked bout upgrading to ETCS 3 to get more out of the system. HS2 will only be the start of ETCS3 it offers advantages everywhere, long after I'm dead something similar will cover the entire network. Part of HS2 use will to be increase redundancy. Being able to move freight over for even a short time would enable work on other lines. Having a known route to self verification would be a lot cheaper the actually installing it.

Maybe so, but if capacity for passenger trains is increased still further it makes it even less likely that freight will be able to run. And it's not really a matter of freight hopping on and off the network either - the connection at Euston would probably be unusable without shunting a freight up against the buffer stops, and the next one will probably be at the infrastructure depot in Calvert with the one after that being near Lichfield. With the engineering access issue to worry about as well, it's hardly going to make a big difference to shifting freight.

The problem with the smart tail light how do you actually know it is at the end? You also need a cable connection all the way through the train. Then of course if your reordering a train or deleting or adding wagons, how do you know it's at the end? It sound simple but the deeper you look the more complex.

A smart tail lamp could be designed to block the brake pipe and coupling so preventing anything being coupled behind it. It could then be programmed with the train's reporting number and transmit "pings" by radio as long as it was healthy and detecting pressure in the pipe. Non-receipt of these at the loco would send some kind of an alarm to the Level 3 system to stop any following trains. Thinking about this, it might be possible just by monitoring the pipe pressure at the loco and dispensing with the smart tail lamp altogether.

However you're never going to get away from the human element, as you rely today on people connecting and testing the brakes to avoid a disastrous runaway.

Does anyone know if ETCS3 allows closer running for slow trains? Is the block size based on velocity and braking power?

Yes. But this doesn't make much difference on a route like HS2 where trains are running at a uniform speed. It would simply allow trains to queue up closer together if there was a blockage ahead. Nor will it help with the terminal capacity at Euston which is also a limiting factor on the capacity of HS2.

 

[thenorthern]

For some reason, I think that those initial services were run without TASS because it hadn't been fully installed yet, so it was essentially a new train running at old speeds, but I may be wrong, and am interested to find out if this was the case

I think that may be right I think TASS started becoming operational in 2003. Its weird to think that before Pendolinos the trains used used on the WCML before the upgrade only had a top speed of 110 MPH.

I remember taking the train to Oxenholme Lake District in 2001 which did an engine change at Preston which now seems obsolete. When I did the same journey again in 2002 the old had been replaced by voyagers but London to Glagow trains were still using loco-hauled trains. If I remember correctly Virgin Cross Country had finished replacing its fleet before Virgin West Coast.

 

[flypie]

Yes. But this doesn't make much difference on a route like HS2 where trains are running at a uniform speed. It would simply allow trains to queue up closer together if there was a blockage ahead. Nor will it help with the terminal capacity at Euston which is also a limiting factor on the capacity of HS2.

No but it might on commuter services like Merseyrail.

It is possible to send digital signals down hydraulic lines, so you might be able to establish 2 way comms between Loco and Light. You don't want to use radio as it can be hacked and get lost in tunnels. This downwell system is a bit extreme.http://www.halliburton.com/public/wd/contents/Data_Sheets/web/H06965_Digital_Hydraulics.pdf

 

[Carlisle]

I think that may be right I think TASS started becoming operational in 2003. Its weird to think that before Pendolinos the trains used used on the WCML before the upgrade only had a top speed of 110 MPH.

I remember taking the train to Oxenholme Lake District in 2001 which did an engine change at Preston which now seems obsolete. When I did the same journey again in 2002 the old had been replaced by voyagers but London to Glagow trains were still using loco-hauled trains. If I remember correctly Virgin Cross Country had finished replacing its fleet before Virgin West Coast.

Yes I remember Operation Princess was Oct 2002 which meant cross country from then on became an all Voyager operation plus about I think 4x 5 coach HST sets they called Challangers that lasted for about another year, it must have been around 2004 before the pendilinos were in full service

 

[61653 HTAFC]

Yes I remember Operation Princess was Oct 2002 which meant cross country from then on became an all Voyager operation plus about I think 4x 5 coach HST sets they called Challangers that were about for another year, it was a couple of years later before pendilinos were in full service

The proposed 2+5 HSTs never happened. The plan was to re-engine the power cars, refurbish the trailers, and the sets were AIUI planned to revert to fixed(ish) DEMU (255) classification.

 

[edwin_m]

No but it might on commuter services like Merseyrail.

It is possible to send digital signals down hydraulic lines, so you might be able to establish 2 way comms between Loco and Light. You don't want to use radio as it can be hacked and get lost in tunnels. This downwell system is a bit extreme.http://www.halliburton.com/public/wd/contents/Data_Sheets/web/H06965_Digital_Hydraulics.pdf

Moving block is used on some Underground lines so might be suitable for Merseyrail, although there is the added complication that if there is an incident you are probably better keeping following trains back rather than having three or four queued up in the tunnel where if evacuation is needed it will be much more difficult.

Secure radio communications has been used to authorise train moves on RETB for several decades and is used in many other environments too. ERTMS level 3 itself will not work without a reliable fast secure radio protocol that maintains continuous contact with the train anywhere along the line. So it is not reasonable to insist that the train integrity proving element has to have a cable.

But I thought we were discussing high speed lines, and we're getting a long way from the topic of tilting anyway!

 

[The Planner]

Which considering GSMR is still a bit flakey in places isnt going to be for a while yet.

 

[Carlisle]

The proposed 2+5 HSTs never happened. The plan was to re-engine the power cars, refurbish the trailers, and the sets were AIUI planned to revert to fixed(ish) DEMU (255) classification.

Ok cheers so it must have been a 2+6 HST I went on then shortly after operation princess, I remember how very worn the interior looked and I think it was down to only one working power car

 

[sprinterguy]

The proposed 2+5 HSTs never happened. The plan was to re-engine the power cars, refurbish the trailers, and the sets were AIUI planned to revert to fixed(ish) DEMU (255) classification.

Not as "Challengers" as you describe, but:

Ok cheers so it must have been a 2+6 HST I went on then shortly after operation princess, I remember how very worn the interior looked and I think it was down to only one working power car

Virgin Crosscountry’s HSTs did operate as 2+5 formations in the final year of operation from October 2002 until September 2003, so that they could keep to Voyager timings following the introduction of Operation Princess. It is just that they were never refurbished and designated as “Challengers” as proposed. I think there were more than about four sets still extant as well, in an increasingly run down condition (They were in a right old state by the last day).

 

[flypie]

Moving block is used on some Underground lines so might be suitable for Merseyrail, although there is the added complication that if there is an incident you are probably better keeping following trains back rather than having three or four queued up in the tunnel where if evacuation is needed it will be much more difficult.

Secure radio communications has been used to authorise train moves on RETB for several decades and is used in many other environments too. ERTMS level 3 itself will not work without a reliable fast secure radio protocol that maintains continuous contact with the train anywhere along the line. So it is not reasonable to insist that the train integrity proving element has to have a cable.

But I thought we were discussing high speed lines, and we're getting a long way from the topic of tilting anyway!

I'm assuming that they will insist on direct communications with the Cab rather than via an intermediate.

It part of the technology that will make tilting more common/cheaper.

 

[DownSouth]

The problem with the smart tail light how do you actually know it is at the end? You also need a cable connection all the way through the train.

No you don't. Wireless ETD/SBU units have been in regular use on thousands of trains every day across many countries including the USA and Australia where trains over three times the length of a British freight train run on tightly curved routes carved into hilly terrain.

Longer term, a shift towards introducing ECP on all new freight rolling stock (and subsidising a retro-fit program) would be desirable, in order to upgrade the handling of freight trains so they have braking performance more like a multiple unit and can then run at higher speeds. In that case, you would have data cables linking each wagon.

Then of course if your reordering a train or deleting or adding wagons, how do you know it's at the end? It sound simple but the deeper you look the more complex.

If using a ETD/SBU, you would know it's at the end because you'd have the ground staff take it off and put it on the end each time a change is made to the train length.

It would be just as simple if ECP rolling stock was in use, except that it would be plugged into the last wagon's data connector instead of being completely wireless.

It would not be complex, purely because the hard work of resolving the complexity was done back in the 1980's.

 

[MarkyT]

For variable train length confirmation in a moving block system one could use a hybrid system combining data from a fixed train detection system (track circuit or axle counter) and front cab position sensing using well proven combinations of odometry, satellite positioning and balises. I have a firm belief that around junctions some conventional train detection will always remain to confirm absolutely the absence of vehicles before moving the points. When a train has passed over such a junction and cleared the dead-locking section the position of the cab relative to the known fixed position of the section boundary can give an accurate determination of the train length, which can then be used in calculating the safe spacing of following trains on the plain line beyond.

 

[flypie]

For variable train length confirmation in a moving block system one could use a hybrid system combining data from a fixed train detection system (track circuit or axle counter) and front cab position sensing using well proven combinations of odometry, satellite positioning and balises. I have a firm belief that around junctions some conventional train detection will always remain to confirm absolutely the absence of vehicles before moving the points. When a train has passed over such a junction and cleared the dead-locking section the position of the cab relative to the known fixed position of the section boundary can give an accurate determination of the train length, which can then be used in calculating the safe spacing of following trains on the plain line beyond.

It may be that in places extra protection is required but why stick with the existing stuff. The equipment available for detecting objects has got a lot better and cheaper recently radar or lidar could be used.
--- old post above --- --- new post below ---
This Blog I asked the question in order to finish is here http://peterirate.blogspot.com/2014/09/liverpool-to-norwich-via-1980s.html

 

[MarkyT]

It may be that in places extra protection is required but why stick with the existing stuff. The equipment available for detecting objects has got a lot better and cheaper recently radar or lidar could be used.

I say stick with axle counters through junctions. These are significantly more reliable than track circuits, detect only trains rather than other objects and have long standing safety approval for the application. To cover a complex junction with radar/lidar technology fully without leaving any gaps and being able to distinguish between a train and say a maintenance man seems a tall order, and difficulty with such technology at obstacle detecting level crossings does not augur well for its wider use. Whilst I concur that fixed signals in the form of lights on sticks are becoming hopelessly out of date in the communications age, other elements and concepts of the historic signalling toolkit are very well suited to the rail environment, and continued deployment within more modern systems. The axle counter product is also no longer the sole preserve of a small number of higher priced European manufacturers, with Asian companies now also supplying similar equipment.

 

[flypie]

I say stick with axle counters through junctions. These are significantly more reliable than track circuits, detect only trains rather than other objects and have long standing safety approval for the application. To cover a complex junction with radar/lidar technology fully without leaving any gaps and being able to distinguish between a train and say a maintenance man seems a tall order, and difficulty with such technology at obstacle detecting level crossings does not augur well for its wider use. Whilst I concur that fixed signals in the form of lights on sticks are becoming hopelessly out of date in the communications age, other elements and concepts of the historic signalling toolkit are very well suited to the rail environment, and continued deployment within more modern systems. The axle counter product is also no longer the sole preserve of a small number of higher priced European manufacturers, with Asian companies now also supplying similar equipment.

It is not the tall an order and telling the the junction is blocked by a anything is not good.