Thameslink core ATO into use

[The_Engineer]

Change will be fine so long as it's totally safe, fool proof,

Nothing in life is totally safe or fool proof - we can make the risks as low as reasonably possible though. And fools are very good at inventing new ways of defeating safety systems.....

 

[whoosh]

I'm not entirely sure that the bit about sidelining guards (surely it'd be the motormen who were doing the dawdling) is entirely true. It's a combination of the signalling being set up to allow it (ie very short signal spacing)....

I notice XDMs post seems to have been deleted. How odd to believe it was nothing to do with the reduction in service being necessary through the falling in London's population, or the removal of speed control signals, and the change from 4 tracks to 2 tracks from South Kensington to Gloucester Road. No, it was all the unions?!

#rollseyes

 

[Bletchleyite]

Change will be fine so long as it's totally safe, fool proof, and looks after drivers for the long distant future ensuring the future generation drivers can have as successful a career as those who drive today do.

Why?

I can't see any reason why the ability of people to become train drivers (or any other job, for that matter) in future should be protected in any way. It's those doing the job now who need protection.

 

[Dave1987]

Year 2025-30 train captain sitting in cab as computer drives train. No need for route knowledge or braking points required means £35K a year not £70K.

Right...... that’s very very very wishful thinking on your part. Next......

 

[Dave1987]

Jealousy does strange things to people as this post shows.

Indeed. Totally agree.

 

[AM9]

... Change will be fine so long as it's totally safe, fool proof, ...

So everything that currently isn't 'totally safe, fool proof', (and anything short of perfect) should be stopped/withdrawn/never considered. Mmmm, do you drive a car, use plastics, drink alcohol, go into a public place if you feel unwell etc.? If the answer to all of those questions (and a hundred other normal activities) is NO, then if you are a train driver, you must be a hermit living next to your signing-on point. Of course even train drivers have (thankfully infrequent) failures in their duties which is not in any way a criticism of their performance, - the person who never makes a mistake hasn't been born yet. The railway is there to provide mass transport for the public, and employs people to do just that. It is not a job creation scheme that can carry passengers.
The ATO that will assist drivers in the TL core to meet the requirement of a nominal 24tph (30tph max.) service which is dictated by the demands of mass transport in parts of London and its environs. So far, it has passed its first passenger-carrying test. Any incidental issues arising will be dealt with as this new 'kettle of fish' is implemented over the next few months.

 

[transmanche]

So the system 'offers' to run under ATO, and the driver then has to explicitly accept this and is aware they take full responsibility for this

The system 'offers' to run under ATO in the same sense that a green aspect 'offers' the driver to proceed.

 

[transmanche]

ATO will eventually reduce drivers route knowledge in any case, so they won't necessarily know when you start braking, especially in deep fog, whereas now human route knowledge covers that

I don't see that as being the case. In the example of the 1960s Victoria line ATO, train operators would regularly drive the trains manually during off-peak times in order to retain their 'route knowledge'.

 

[AlexNL]

The system 'offers' to run under ATO in the same sense that a green aspect 'offers' the driver to proceed.

No, a TL driver has to press the "ATO Start" button on their desk. This has to be done after every station.

As long as a driver does not do this, the train will not run in ATO mode.

 

[transmanche]

No, a TL driver has to press the "ATO Start" button on their desk.

You misunderstand me. I was suggesting that the 'offer' isn't in the sense of it being a free choice but in the sense of placing something at someone's disposal. Whether a driver accepts the 'offer' will not be at his or her's whim, but according to the booked schedule.

 

[GB]

Year 2025-30 train captain sitting in cab as computer drives train. No need for route knowledge or braking points required means £35K a year not £70K.

Ignoring your first lot of assertions for a moment. Do you think its a good idea for a race to the bottom with regards to pay? Are you under some illusion that ticket prices will magically and significantly drop if a drivers pay was reduced?

A poorer salary pays less tax, less national insurance, stifles economies and growth and has the potential to increase staff turnover.

 

[HSTEd]

Ignoring your first lot of assertions for a moment. Do you think its a good idea for a race to the bottom with regards to pay? Are you under some illusion that ticket prices will magically and significantly drop if a drivers pay was reduced?

The race to the bottom exists, and nothing can prevent it.
I see no reason why any particular industry has any right to be immune when so many are not.

 

[Clip]

Ignoring your first lot of assertions for a moment. Do you think its a good idea for a race to the bottom with regards to pay? Are you under some illusion that ticket prices will magically and significantly drop if a drivers pay was reduced?

A poorer salary pays less tax, less national insurance, stifles economies and growth and has the potential to increase staff turnover.

I dont think you can infer anything like that from their post - merely that they were stating that with a reduced need of skills like route knowledge then the wage would go down.

Myself id say that route knowledge would simply have to be retained for if they found themselves with a train broken down somewhere and so on and so forth however i probably wont be around nor bother in 30-40 years so im not that fussed about the future

 

[GB]

and to counter that, I see no reason why one industry should suffer just because others have.

Whether the race to the bottom or is preventable or not is one thing...we shouldn't be rolling over to make it easier.

 

[AlexNL]

You misunderstand me. I was suggesting that the 'offer' isn't in the sense of it being a free choice but in the sense of placing something at someone's disposal. Whether a driver accepts the 'offer' will not be at his or her's whim, but according to the booked schedule.

That is true. And with a timetable which will be as tight as Thameslink's, a driver not running under ATO can probably expect a call from control even before having left the tunnels.

 

[Tim M]

Another thought, if the technology makes an error, or there is wheelslip or leaf mulch on the line in ATO which couldn't be visually seen, and the brakes are either applied too late or don't stop the train in time of an obstruction such as a bay, and contact is made, who is liable? The driver? The train manufacturers? The software systems? The signallers?

If a train gets dangerously close to the one in front and the driver realises the brake hasn't applied, two seconds pass while his brain processes and presses the brake but the train is already too close and it's like a spad in the traditional sense, who gets the blame? The train?

This has been partially answered by others but the following may be of interest. The use of Automatc Train Protection (ATP) of which ETCS is one example, and Automatic Train Operation (ATO) has been well understood since the 1960’s, ATP in the form of cab signalling since the 1930’s. The alagorithms required for the design of such systems is therefore well understood including allowances for poor rail conditions. For example a lot of effort was expended by my colleagues at Chippenham in the early 1990’s to overcome issues with wet rails on the above ground areas of the Central Line.

Speed and location are measured in three ways, 1. an axle end mounted speed tachogenerator, usually two off, 2. Doppler radar and 3. recalibration of distance travelled at each ETCS track mounted Ballise. On Thameslink these will tend to be close together whereas on the Cambrian these are much further apart. All this data is integrated to ensure the train knows where it is and actual speed adjusted for wheel slip or slide.

It is worth pointing out that ATP is a safety critical system with ATO safety related, SIL4 and SIL2 respectively in accordance with the CENELEC Standards EN50126, 50128 and 50129.

The ATO interstation run can be varied subject to required service performance at the time. Often in order to save energy the run profile will include an element of coasting which can be adjusted or removed if required to catch up a bit of time. I don’t know the specifics of the Siemens ATO or control centre intervention protocols for Thameslink but this sort of facility is core to the regulation of the Victoria Line and many other mass transit railways worldwide.

The application of Temporary Speed Restrictions is part of the ETCS as this is a safety critical function.

The driver is still responsible for looking ahead for incursions on the railway that might require emergency brakes to be applied, with the ETCS looking after safe spacing between trains and at junctions etc. in conjunction with the signalling interlocking. The ATO is subservient to the ETCS and cannot create an unsafe situation, the ETCS being subservient to the interlocking.

In principle the Thameslink and Crossrail cores are being treated as mass transit railways with uniform train sets and calling patterns. ATO ensures uniform interstation run profiles, thus maximising throughput.

 

[Tim M]

If a train running under ATO performs a SPAD while a driver is on board, I assume that it would still be the driver who is held accountable for the SPAD. While under ATO, the driver is there to supervise the machine and to intervene if the situation so required.

A short anecdote may help here. In the early days of Hong Kong MTR when trains were being tested with ATP and ATO reports came in that trains were overshooting station platforms. It was only when one of my colleagues noticed the driver panicking (if that’s the word) and taking the train out of ATO mode at the last minute any trying to stop the train manually that the issue was resolved.

In any case the ATP (ETCS) will have intervened well before a SPAD takes place, irrespective of whether the ATO or the driver is driving. Remember ATP provides safety with the ATO/driver being subservient.

In other words, leave it to the ATO, driver intervention may as demonstrated in Hong Kong create a situation that isn’t there.

 

[Tim M]

There needs to be some clear national guidelines on what happens during an incident when the train is in ATO.

The whole point of this exercise is that the computer can supposedly drive closer to and brake later than a human driver, so a human driver cannot be expected to second guess what the computer is going to do. ATO will eventually reduce drivers route knowledge in any case, so they won't necessarily know when you start braking, especially in deep fog, whereas now human route knowledge covers that.

If the computer messes up in ATO, then the computer gets put on a support anmoniyoring plans removed from driving duties if it space. The driver cannot be the fall guy for a computer says no mess up.

Essentially there are three computers, in hierarchical terms these are 1. the signalling interlocking, 2. the ETCS (which is an Automatic Train Protection system - ATP) and 3. the ATO. If the ATO messes up the ETCS will intervene and stop the train, just as it would if the driver messed up. ATO messes up, its an equipment fault, driver messes up its their fault.

1 and 2 are safety critical and 3 is safety related, or SIL4 and SIL2 as defined in the international standards. Each safety critical system will have its own means of managing safety and availability by duplication, triplication or true and complementary software techniques, these have all been in use for over thirty years in the U.K.

ATO on Thameslink and Crossrail core and many other mass transit railways around the world is used to optimise interstation run times achieving better performance than a human driver can achieve. But yes, it’s a good idea to let drivers drive from time to time or use cab simulators to maintain their knowledge.

 

[Tim M]

For maximum safety positively, i.e. the train can only exceed, say, 5mph, if it has received a positive balise signal saying it can and how long for.

Just a quick correction. The Balise is a passive device that is interrogated as the train passes over it, and is used by the train ETCS to recalibrate distance travelled data. All train movement data is transmitted to the train from the trackside Block Processor using the GSM-R Radio.

 

[Tim M]

Out of interest, can anybody say how a failed, (i.e. dead with no signal emitted) balise is dealt with. If the on-board equipment doesn't sense it, does it expect there to be one at that position and consequently drop into some safety mode, or would it continue operating according to the last authorisation which may have a time or distance validity, (not a particularly safe situation if a string of them are inoperative owing to a signalling power failure)?

Simple answer, the system allows for a dead Balise and waits for the next Balise to be seen by the train. I think that if two Balise are missed this will cause the train to stop and a restricted mode of operation with speed safely limited to say 20km/h until the next working Balise is found.

 

[Clip]

and to counter that, I see no reason why one industry should suffer just because others have.

Whether the race to the bottom or is preventable or not is one thing...we shouldn't be rolling over to make it easier.

Is that in reply to me as I said no such thing

 

[Tim M]

Yes the Underground has been mentioned but as has been said this is the first use on the mainline which is a new kettle of fish for the first time.

Well not really if you consider both the Thameslink and Crossrail cores are in reality mass transit railways that extend onto other lines out of the core. Apart from the use of ETCS outside the core I don’t see a huge imperative to extend the use of ATO, but it could if the business case stacked up.

Your comment “Yes the Underground has been mentioned” as if it’s some minor network. Remember the Underground carries more passengers than train Operating Companies on Network Rail, hardly minor.

 

[Bald Rick]

It's possible that German driving policies allow Deutsche Bahn to run 28tph without thinking it's necessary to use ATO, this might be due to their driving policy. In my experience with German drivers they can be quite... aggressive, coming into a station at a high speed and only slowing down at the last moment.

The combination of LZB and AFB indeed allows a train to run on its own, and it will accelerate and slow down according to the information received from the infrastructure. However, as the AFB driving style can be pretty harsh so drivers prefer to brake a bit earlier or accelerate a bit slower than AFB would for comfort reasons.

The Münich S Bahn core operates at 30tph, it has a form of ATO, and also has short dwell times (30 sec) enabled by ‘Spanish’ platforms at the busiest core stations.

I think this is where the DAS system comes in and is supposed to ensure trains arrive in the right sequence at the entry to the core.

Anyone know what stage of development it has reached?

It’s the Traffic Management system that will help get the trains in the right (or best) sequence. The core is just like a pipeline, a train goes in one end, and comes out the other 9 mins later.

Almost all trains have 2 minutes recovery time approaching the core, plus 1 minute leaving, plus extra in dwells at some stations on approach (especially London Bridge and Finsbury Park). This will deal with all the minor late running. It will also deal with trains out of path - they will retain their lateness through the core (not recovering, nor getting any earlier) however the following train will be 2 minutes later than it otherwise would be. The pathing time on core exit recovers half of this.

 

[Bromley boy]

It’s the Traffic Management system that will help get the trains in the right (or best) sequence. The core is just like a pipeline, a train goes in one end, and comes out the other 9 mins later.

Almost all trains have 2 minutes recovery time approaching the core, plus 1 minute leaving, plus extra in dwells at some stations on approach (especially London Bridge and Finsbury Park). This will deal with all the minor late running. It will also deal with trains out of path - they will retain their lateness through the core (not recovering, nor getting any earlier) however the following train will be 2 minutes later than it otherwise would be. The pathing time on core exit recovers half of this.

Interesting, thanks for this.

 

[SPADTrap]

I see no reason why any particular industry has any right to be immune when so many are not.

Unionisation, sorry .
Let us know what it is like at the bottom, survival of the fittest and all that.

 

[Bald Rick]

Unionisation, sorry .
Let us know what it is like at the bottom, survival of the fittest and all that.

Oh the irony!

 

[ComUtoR]

One of the problems with 'The Core' is the dwell times and passenger loading. Considering the Driver controls when to depart, I do wonder how much those decisions will impact the benefits of ATO. Before the man with the cunning plan jumps in; I am aware of the benefits of FASDO and 700 PTI.

 

[3141]

Without reading through all five pages I don't know if anyone's posted about the item on this subject on the BBC News website yesterday. It said that the RMT had expressed concern about the railways becoming faceless.

 

[AlexNL]

That's why the 700s don't just have ATO, but are also equipped with a Driver's Advisory System (DAS), this Network Rail presentation on the IRSE website has some pictures of it: http://www.irse.org/knowledge/publi..._Seminar_Oct_2014_v5_[Compatibility_Mode].pdf

 

[HSTEd]

Unionisation, sorry .
Let us know what it is like at the bottom, survival of the fittest and all that.

Worked out fine for coal miners.... and for guards didn't it?
The trade union movement is spent as a significant force - even ASLEF will succumb eventually.