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Following the fitment in the vast majority of HST cabs and the training of most of the drivers, following a successful trial period since the turn of the year, the DAS system is now in operation.  I was wondering if any of the passengers have noticed anything different about their journey over the last few weeks as a result, or whether the subtle differences are not noticeable unless you're in the cab?

This is an example of the system in operation, which I thought some of you might be interested in.

(http://farm9.staticflickr.com/8147/7137023535_1d1bc16954_n.jpg)

The bottom left hand of the screen show the current time, the time due at the next station and an ETA based on what time the train would arrive if it continued at the current speed.  The bottom left hand side gives the next station (or timing point), the type of train and the current location in miles and chains.

The top part of the screen shows what the driver is being advised to do, together with what should be done next.  So in this example, the system is saying that in order to arrive at the next station on time the driver should not exceed 115mph and then be prepared to coast until told otherwise.

I was a bit sceptical, but I have to say it's a pretty neat system.  It will make allowances for gradient, ruling linespeeds, train performance and TSR's, but not signals.  FGW expects to save a lot of money on fuel over the whole fleet as getting up to 115mph and then coasting for, say, 10 miles, is far more fuel efficient than caning it at 125mph and sitting outside Reading station waiting a platform for 5 minutes!  The unions are also happy with it as it should mean that drivers come up against fewer restrictive signal aspects.  Their support was also secured when the drivers were bribed encouraged to use the system with a bonus payment scheme.

There are a few limitations though as it really needs a gap of at least ten minutes between station stops in order to be effective, so is of marginal use on the Cotswold Line for example.  That being said, having an accurate clock and accurate readout of your location in miles and chains will be welcomed by drivers.

Just shows how lax the schedules are  ;)

Thank you Indiustry Insider for explaining what the DAS does.  Certainly a very useful system eg for identifying where you are on a dark and foggy night down the Costwold line.  Clearly there is a potential conflict with other systems eg TPWS, which may initiate a brake application whilst DAS is advising you to do 125, which is one good reason why we still need a Driver at the front. 

But maybe one day .....

 ::)

I've just been given some new software for my work laptop which will help me do my job more easily. Funnily enough, I'm not being paid a bonus to use it...

Very interesting - thanks IndustryInsider.

One question I have is if the system is clever enough to know when a train needs to speed up to help out a train stuck behind in?  E.g. Two HSTs with one behind the other approaching a junction where their routes divert.  The one behind is running late but the one in front is being told to coast at 115 whereas in actual fact it would be better to do 125.

Thanks,

Boppy.

Can it tell how far the train in front is/ whether there is a clear path ahead? Otherwise, one train could be doing 115 and another doing 125, with one catching up with the other.

Please add my thanks for the article...although sadly on my nightly HST between Reading and Thatcham I don't think it will be of much use but interesting all the same.

You asked if anyone has noticed a change in driving style. I did Reading to Plymouth and return yesterday and more than once was aware that we were coasting for extended periods. First time I have noticed this. I sat in coach D on the way back and tracked progress on the moving map. The driver kept very closely to line limits and made good use of the down hill sections. We ran to time almost all the way to Reading before being held for a couple of minutes at Nelson's hat, for a slightly late arrival at Reading.

I know that what I am about to suggest may not be viable...but I would like to see some of the info on the screens in Coach D...but then I'm a bit of a gadget freak who would probably watch the sat map on a plane than watch a film!

Could of been on a service with Turbo based timings

All Oxford services are Turbo based timings as we're the first to get our HSTs pulled. Even the fasts take a whole hour, which is madness really!

I don't think it does make allowances for gradients as such and as far as Devon and Cornwall is concerned I suspect it still needs a bit of fine tuning. Shutting off at Dauntsey old station going towards Swindon isn't to my mind sound advice.

However I can see why First are bringing the system in and it is actually a very good idea.

At the end of each run it gives the energy for the journey in Gigajoules. The figure on the display being that for the power car concerned and not both power cars.

One Gigajoule = 277.78 KW/hrs which with the 16V4000R41 specific fuel consumption being 195gm / KWhr and allowing for about 91% alternator efficiency equates to 16.4 gallons of fuel.

On certain trains it isn't actually neccessary to run the train at anywhere near line speed to keep time. The drivers you will find are aware of this and drive accordingly. 1A74 being a case in point. If it passes through Newbury at its booked passing time the driver can close the controller and roll the entire way to Southcote Jn and still pass that point early despite being down to around 75mph passing through Theale.

DAS is adaptive however and doesn't attempt to advise drivers to coast etc when the train is running late. Once the train becomes around 6 or more minutes late the DAS will display 'Advice not available, late running' and the driver will then drive the train in the normal way driving the train to make best use of the line speed parameters. Economy being of secondary importnace to punctuality.

DAS is a 'stand alone' system in the power car (although it must be linked to the power controller / engine MDEC box to give a 'Gigajoules used' figure) using GPS technology, the receiver head being mounted behind the horn grille. Therefore it isn't possible to feed it back down the 36 way control cable for display in the passenger coaches.

The Volo screens only show the moving map for about a minute or so before going back to default so you'd need to be pretty keen to follow progress that way. 

Not anymore! A message pops up and asks 'Is the screen still in use' You just tap the screen to remove this and the map remains.

I travelled Bristol to Plymouth with FGW the other day. The Volo moving map was stuck permanently just outside Reading. One hopes the accuracy of this Driver Advisory System is a little more robust.

There can also be a case of 'too much information' sometimes. There are well documented accounts of airline pilots getting into to serious trouble because they relied too heavily on the technology and not their common sense.

For some reason I notice the other day what I assume is the GPS receiver on the top of coach D. Look like is has been borrowed from the roof of a well known German car!

Seems useful, especially in an age when cheap fuel isn't even available to public transport. After passing a certain price per litre of fuel, I realised when driving that coasting to a junction is cheaper than hurtling to it in top, then braking. I'm guessing a train driver doesn't always have the visual cues to help judge the best economy / speed balance, and this looks a good aide. It's not just fuel either - my brake pads on my car are now into their third year, whereas a colleague with a similar car has changed his twice in the same period.

I suppose the optimum economy will only ever come with a fully traffic-controlled railway system, where a driver never meets a red light, because the path has been so precisely calculated to fit in with other trains. Maybe in a couple of hundreds years....

So if a train is 5 minutes late, it will still tell the driver to coast? >:(

How often will the speed update? Do we want drivers constantly looking at the screen and not at the rails?

This being one of the issues raised by the incident with the wheel falling off the Meridian on the MML recently.

http://www.raib.gov.uk/cms_resources.cfm?file=/120130_R012012_East_Langton.pdf (http://www.raib.gov.uk/cms_resources.cfm?file=/120130_R012012_East_Langton.pdf)

Too much garbage being displayed on the TMS screen, driver attempted to interrogate screen and understand / make sense of what was going on rather than actually stopping the train promptly.

The system is an aid and not a mandatory driving requirement. There is therefore no expectation that drivers will gawp at the DAS screen instead of looking where they are going or at the other instruments in the cab. Having driven a few power cars with DAS on I have found that the degree of coasting advised is in respect of the degree of lateness and the time allowed to the next intermediate point or station.   

I have it from a reliable source that its not great and doesn't take into account trying to make it to the destination on time

Although it is better than the 180s which apparently feel the need to inform the driver if, for example, the toilets are out of order!

There are equally well documented accounts of disorientated aircrew relying on what they thought was their "common sense" instead of reading their instruments, and flying plane into the ground  :-\

That depends of course how slavishly you follow the instructions displayed on the DAS screen.  ;)

Its rather like satnav in a car, it requires a degree of interpretation. Rather than following to the letter which tends to end up with HGV's stuck on narrow roads or old dears turning right onto railway lines at level crossings....

The incident with the Jumbo Jet getting into mega problems in high cloud years ago being a case in point. Pilot became disorientated to the point where he believed the 'artificial horizon' instrument had failed and only managed to regain control when the plane had fallen several thousand feet to the point where he could see the sea, reorientate himself and effect a recovery.


There is however a point where too much information and gadgetry in a driving cab or cockpit can be counterproductive though.

They must have changed that since I last travelled any distance in a Volowagon then....

But we should be identifying slack and tightening the schedules not driving slower! This will just make early running a thing of the past, and the slack will never be axed.

This may also increase delays. Let's say there are a couple of bikes and a passenger that requires assistance at X station. Instead of driving at 125mph and arriving a few minutes early, the train will only turn up on time.

Nothing wrong with getting to stations early IMO!

Except for the benefits already mentioned when aiming to arrive on time, namely reduced fuel consumption which is cheaper and better for the environment.

Yes but at certain stations on the GWML getting into stations early is impossible. If you get a green on the signal on the down main at Kennet Bridge Goods Loop / Oracle indicating route clear into platform 7 at Reading its either a Sunday, your running mega late or theres a major signal fault. Its the same as trying run early towards West Drayton on the up main, you know your going to get two yellows on UM13B (while the HEx goes first) so why bother.

With DAS, you can now let the train run from somewhere round Maidenhead and still get into Reading on time rather than ranting the thing along at 125mph and then dribbling in on yellows from Sonning, thus saving fuel and brake pad wear.

I doesn't seem to be perfect on the gradient front, but it definitely does take gradients into account, at least that what I was told, and in my own (fairly limited) experience it tells you when to coast (virtually to the second) at the summit of hills near Culham and Chipping Campden.


Valid points, though the data can be interpreted and you can see how much coasting is going on and still work out where the slack still is of course.  And to answer earlier questions the system has no interface with the signalling system so there is no allowance for signals and proximity of other trains.

Not sure who your reliable source is, but the sole purpose of the system is to take into account trying to make it to the destination on time!

It seems to be ok on routes East of Exeter but it gets into a right tizzy West of there to be honest. I find that I can usually out-DAS the DAS on the economy front on the Exeter - Plymouth section. In general on the B&H I find that its sugested course of action and what I do (based on what drivers taught me when I learnt the road) pretty much coincide exactly. I know one of the drivers who was co-opted to work with the DAS engineers while the system was being set up so that doesn't unduly surprise me.

Let's hope the situation west of Exeter is tweaked then - though the proximity of the stations, especially when you get into Cornwall might limit its usefulness anyway.  I can see how on the B&H it would come in very useful with the extended gap between station stops.  Thanks for the analysis on the fuel consumption by the way.

DAS doesn't have that capability. What it should do is assuming both trains are running correctly in their booked paths is advise the driver on the second train to also run at 115mph which allows both trains to reach their next calling point on time. If the second train is out of course / late and running off its booked path behind the first one, DAS on the second train will be showing 'Advice unavailable late running' anyway.

You can't really drive trains on the basis of what you think might be behind you, you have to concentrate on driving the one your sat on. Train regulation is the signallers responsibility.

Which means that if you have a HST with power notches locked out or worse still running on one engine you garantee that the train will run late and be much later than it would if a degree of recovery / pathing time was allowed. As well as Pway TSR's, signal checks etc etc.

The 10:06 PAD-PNZ will keep time (or at least not loose further time) Reading - Exeter on one power car providing traction power. I know, I've done it....

Yes, but power cars locked out should be a rarity. Do the WCML schedules assume the tilt will be broken? No, they assume the train will run at 125mph. FGW should timetable the trains to assume no technical problems. Obviously some is needed for recovery time, but 60 minutes to Oxford is a joke!

That fact about the B&H is shocking. How much slack is there?

I bet if you went into the specifics of WCML timetabling you'd find you were wrong and the 390's don't have to run flat out everywhere to keep time. Last one I went on, Warrington BQ, right away Euston contrived to get into EUS about 12 early which suggests there might be a bit of slack in their timetabling too. Customers prefer a railway that gets them there right time (or early) most of the time than some half assed numpty railway that delivers them right time about 10% of the time and with varying degrees of lateness the rest of the time. It's easier to plan your life around that...

I'm afraid if you assume that there will never be power cars missing power notches, Temporary Speed Restrictions or signalmen with finger trouble and timetable on the basis of full bifters everywhere you will end up with a raliway with shocking punctuality / relaibility figures and one which uses about 15% more fuel as the drivers charge around flat out.

Sounds a good system and thanks IndustryInsider for posting it and to The SprinterMeister for adding to it.  A fair few times I was on the 15:00 from Plymouth to London Paddington when it used to have a restaurant on it and it would belt up the Berks & Hants only to sit outside Reading because it was up to 10 minutes early and there wasn't a platform for it.

As for Power Cars not being at full efficiency there is a timing run on the newly doubled Coltswold line reported in the latest Railway Magazine using a Turbo and an HST - with the HST driver reporting that notch 5 seemed to perform the same as notch 4.   If there was no slack in the timetable the temptation would be to cancel such a service to prevent it delaying other trains.

That explains a lot as to why the other week between Paddington and Reading on the 8am to Bristol on a Saturday morning instead of thrashing it to Reading we cruised and I was wondering why this was. Now I know.

That would probably be due to N5 being locked out on one or both power cars.

There are maintenance procedures which require N5 to be locked out, ie traction motor issues such as worn brushes or for a period of 24 hours after the brushes are replaced to allow them to bed in.

The Didcot Herald, courtesy of 'WillC' has published an article:

http://www.heraldseries.co.uk/news/hsdidcotnews/9690476.Hi_tech_device_puts_train_operator_on_track_to_fuel_savings/ (http://www.heraldseries.co.uk/news/hsdidcotnews/9690476.Hi_tech_device_puts_train_operator_on_track_to_fuel_savings/)

Definitely a good thing!

Does anyone know where in the cab these new screen are situated?

Out of curiosity are these only fitted to HSTs? At the other end of the scale I have noticed the journeys on the north downs line seem to involve alot of coasting . I remember noticing this before this (very interesting) article on DAS was posted.

Just HST's (and eventually the 180s).  Though more and more emphasis is being made to drivers to coast where possible to save fuel as a general good driving technique.  Depending on the profile of the route there are many occasions where coasting has to be done to avoid speeding anyway.  The North Downs line, whilst not having many really sharp gradients still has a number of areas where the gradient and prevailing linespeed mean that coasting is a sensible thing to do.

Right hand side between traction ammeter and Driver guard handset  / ATP data entry keyboard.

Or ocean in the case of the tragedy with the Air France A330.

Instruments help a bit. I learned to fly light aircraft. Part of the training, even if you are only ever going fly in clear sky, involves learning what to do if you end up in cloud. You use instruments to do a 180 degree gentle turn, without losing height, on the grounds that if you didn't hit anything on the way in, you probably won't on the way out. First time I tried it, with an experienced instructor on board, I concentrated on the instruments, making what I could tell from the seat of my pants and the instruments was a slow, level descent. Came out of the cloud at a crazy angle, some distance from where I thought I was, with much guffawing from the right-hand seat... so much for seat of the pants!

As any lorry driver who has jammed a 40-foot artic in a country lane will tell you, instruments are a servant, not a master, and need to be practised  to be understood. You also need to know what to do when they go wrong, and I guess DAS is another aid to the driver, not a substitute for learning the route. But, whilst knowing little about driving a train, I am willing to bet that there are old-timers who will snort at the very idea that this "black box" knows better than them, but will have a crafty glance anyway, and someone who won't speed up / slow down because "computer says no". Then there will be someone who throttles back to coast, or powers up again, less than a millisecond before DAS tells him to. He will be an annoyingly good driver, despite his tender years, and will win "Driver of the Month" or whatever, to the applause and chagrin of his longer-serving colleagues.

Still one or two issues to be ironed out as DAS doesn't seem to recognise the concept of Set Down Only trains (like 1C32 beyond Bristol TM) which don't have to wait for a booked time as they are not picking up passengers. Seem to be one or two issues with the GPS reception between Tilehurst - Goring and Streathley due to the trees now being in leaf.

(Top tip for all you GPS-ists, do not get lost in a forest with masses of wet leaves overhead as you'll loose the signal ;))

Very interesting five page article on DAS in the August Railway Magazine which, like most magazines, is out in July!

It's like any GPS based gadget, DAS is an aid but requires a degree of interpretation to get the best out of it. The issues with gradients West of Exeter haven't quite been ironed out yet and it's possible to coast more on certain stretches than DAS would have you think. It's possible in fact to roll all the way from Wrangaton to Lipson Jn with no loss of speed / time and you will in fact reach Plymouth albeit not very fast, you won't have to brake much for the 25mph in Mutley Tunnel...

On the easier gradients East of Exeter the system works fine, FGW /  TTG had a very experienced driver on light duties at that time who input his considerable experience into the system, certainlyt as far as the Berks and Hants line was concerned.