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HS2 VIPs…very important passengers

It is people who form High Speed 2’s greatest challenge. But not those in the Chilterns worried about a 225mph line running through their area of outstanding beauty, or those of the Westminster Village who oppose the scheme simply because it’s the political game they play.

No, the people forming HS2’s greatest challenge are its passengers. They are some way off - the line isn’t expected to be running until 2026 - but they are occupying an increasing amount of time for the team designing the network, according to Chief Engineer Andrew McNaughton.

The challenge comes in unloading and loading 1,000 passengers in the 20-minute turnaround each train will be allocated at terminus stations such as Euston.

As McNaughton relates: “We’re not designing a bit of infrastructure, we’re designing an operational system that includes the trains (that’s the easy bit), and we are designing around people.

“We have to be able to demonstrate an operational system that will work, not just an engineering system that will work. There has been some talk about how do you accommodate 18 trains per hour on a line - that’s a bit interesting, and not that difficult. We’ve said our specification is two-minute station stops, so how do you create a station design that enables you to allow people to board or alight in that time?

“We’ve said 20-minute turnarounds at Euston because if you have longer turnarounds you need more platforms, and if you need more platforms you need more space, and you have a bigger land-take and a bigger impact. So we’re saying: ‘right, you’ll have this much space for bigger platforms, how are we going to load and unload those trains in a 20-minute turnaround’? So that’s part of our system design of our whole system - it’s not just about tracks and trains.”

The 18tph figure comes from work McNaughton’s team has done to examine what capacity the proposed high-speed line can realistically deliver. The figure comes from a combination of train speed (100 metres per second), train length (up to 400m), braking performance, driver reaction times, and the time it takes for radio signals to be delivered and processed between the train and the signalling system.

The arguments about the line’s capacity come from viewing HS2 from the experience of existing railways. Says McNaughton: “There’s nothing in that we don’t have a proven technology to use. ERTMS Level 2 will work 18 trains per hour - I’d love to have a better system because it will work it easier and it will be less demanding. Nobody runs 18tph with ERTMS Level 2 because they never set out to. We’ve set out a whole system - it has acceleration lanes, deceleration lanes and what the guys from Arup call ‘roll-in, roll-out’ at stations, so you roll one train in as you roll another out.

“If you design your whole system you can achieve your 18 trains per hour. If you just say ‘we’ll buy a fancy control system’ then you can’t.

“Years ago, on the West Coast Main Line, when the whole debate was about train control systems, I remember that I made myself very unpopular when I said: ‘I don’t care what train control system you have here, your timetable demands two Down trains stopping at Watford within a minute of each other, but there’s only one platform’. There is no control system on Earth that can put two trains on one platform simultaneously.

“So that’s your engineering system design, of which your control system is just a little bit. You come down to what’s the speed of the turnout, and all that operational stuff that you have to do to demonstrate that you could run 18 trains per hour.”

Still musing on the 18tph topic, he argues: “You couldn’t do 18tph if you just had turnouts at the stations. You don’t turn off the motorway at 20mph, you turn off at speed and then you slow down. That’s system thinking, not railway design thinking.

“You cannot think of this as a traditional railway. It irritates some traditional railway people when I say this is a new transport system that happens to be steel wheel on steel rail.

“But it’s the way you think about it for the 21st century, when you have all the privileges of not being hamstrung by what you’ve been given by your father, your grandfather and your great-grandfather. Which is why you’ll never get this capacity out of the existing railway, because the existing railway is configured the way the existing railway is configured.”

At Euston, HS2 is constrained by the station’s surroundings. The plan to expand the station from its current size is expected to lead to homes being demolished - a clear example of what McNaughton describes as the “impact” of HS2. Once again, impact is all about people, and those impacts will form a major part of the Hybrid Bill process that should start next year.

McNaughton explains: “A lot of the Hybrid Bill is about why you need someone’s land. The Hybrid Bill is not a set of construction drawings - I think many people understand that, and many people don’t. The Hybrid Bill gives you rights to take land and build a railway. It doesn’t give you the rights to take land and build a 12.00m this or a 14.00m that.”

He adds that the Hybrid Bill will not specify HS2 as an 18tph railway - rather, the 18tph forms the basis from which HS2 calculates the impacts and benefits of its railway.

Along the route, noise is considered to be one of the impacts. HS2 models its noise impacts around this number of trains for the purposes of the Hybrid Bill. If better design over time cuts the noise that trains produce, and signalling advances allow a higher line capacity, then more trains could run provided noise limits are not breached.

Says McNaughton: “We’re modelling the noise and the benefits on 360kph (or in old money 225mph), with a provision that as technology develops you could run a little bit faster (which gives greater benefits) but at no worse impact.

“So if you took the same trains and ran them at 250mph you’d have a greater noise envelope. If you had a train that could run at 250mph and emit the same noise as ours at 225mph then you could run it because you’re not impacting people any more. So the Bill is about the maximum impact.”

For Euston, HS2 could ease its work by planning an even larger station to give itself more platforms. But this would increase the number of demolished buildings and the impact on local communities, as British Rail found to its cost when it first planned to sweep away much of the King’s Cross area for its Channel Tunnel Rail Link (before revising plans to focus on St Pancras station, giving the HS1 we see today).

It’s here that HS2 as a network comes into play, because the Hybrid Bill for the first phase (London-West Midlands) must include provision for land needed for the second phase. And here lies a trap that HS2 must not fall into if protesters argue against the Hybrid Bill on the grounds that it proposes to take more land than it needs for the first phase.

McNaughton notes: “The technical challenge is that we’re creating a new network. We’re being asked to develop a Bill for a first stage. So this is not building a new London to West Midlands railway, for which there is probably now a whole suite of people focused on the best way of mitigating noise at ‘x, y and z’ locations, and is the alignment quite right as it passes ‘x or y’, and do we have the right amount of land and the right construction sites.

“The technical challenge, and the focus, is on creating the ultimate network (which initially could be described as the Y network because that’s what the Secretary of State has articulated). So London-West Midlands is built as the first stage of the network, not as a standalone entity that you then try to bolt something onto.

“You could say that for London-West Midlands you don’t need the full Euston or Old Oak Common, or you don’t need the full Birmingham Interchange. You certainly don’t need the full-size Birmingham central station at Curzon Street, because the first stage only has trains to London. It’s only in the second stage that you have trains to Manchester, Leeds and maybe Glasgow. Therefore as a technical directorate our job is to specify what the full scheme needs, which the London-WM team then works up into drawings.

“Similarly, the first phase does not require a capacity of 18 trains per hour, but it’s jolly hard to build half a control system or to say ‘we don’t need a deceleration track at Birmingham… we’ll just come along and build that in later - oh, but we need the land for it, so it has to go in ’.”

McNaughton is determined to break away from current railway thinking, which is necessarily constrained by the railway it has rather than the one it might want.

Chief among this thinking is how passengers will reach HS2 trains, and here he is clear: “We start with ‘You’re not end-loading and unloading’. You’re not going to have a trolley dash like Euston on a Friday night. Therefore you are designing a system where, by lifts and escalators, you put people in the right places on the platforms, or they’re very close to where they’re going to sit on the train.”

He dismisses the railway concept of platforms, in favour of airport gates or the systems that sports stadiums use to guide spectators to their seats. You might walk to a gate, or take a travelator, but it will be positioned close to the carriage where your seat is.

“So you don’t actually have a ticket for the train, you have a travel permit that lets you through a particular gate to go to a particular seat. This is not how we’ve done railways in the past. But it’s not science fiction either.”

He continues: “So when you travel on HS2 you are travelling on an HS2 system, you are not just travelling on another bit of a railway. That’s really important. And to get to your gate - you might walk it or you might be some place like Curzon Street where the entrance might well be at one end and so you use a travelator to get 300m up the track.

“But think of somewhere like Blackfriars at the moment, where you have two entrances. At Curzon Street, when they develop the area there may well be a northern concourse and a southern concourse. But people may want to be at the other end of a 400m train, so you get your travelators to the place where your escalator takes you to the platform. And then you’re within two coach lengths - a maximum of 50m - of your seat.

“You’re going to have to provide support for those people who are mobility-impaired. Another part of our remit is that it’s a railway for everybody. It’s not a railway for those who are young, fit and carrying a laptop. So it has to be a railway for those people with suitcases, for people with heavy luggage and prams, for people with children, and people who are not in the first flush of youth.”

HS2’s chief engineer paints his network as a mass-transit system, rather than a conventional railway: “The system design around a 20-minute turnaround of a 1,000+ seat train is a system design that caters for not just the people who turn up at the last minute, but the people who turn up an hour beforehand. How do you fit retail into that (because some people quite like retail)? And how do you avoid it being like Terminal 3 at Heathrow, where the only way to the plane is through the perfume counter?

“Because we’ve done a design around 10 platforms and 18tph, therefore you have to turnaround two trains an hour in each platform, which means you have to design the throat to get the trains in and out without the throat being in conflict. This is why at Euston we end up with a grade-separated throat so that you can reliably service 18 trains in the 10 platforms.

“This means you have to use each platform twice an hour - you have to have a bit of give so you come back to a 20-minute turnaround. So how do we lift people off the trains, service the trains and lift people on to the trains in that turnaround time? That is the system design and, frankly, what happens with the trains and the signalling control is trivial in comparison.”

The answer, he reckons, is to design a station through which passengers can intuitively navigate. He’s rejected Japanese advice to train his passengers to use HS2 stations, which, he says, “sounds horrible”.

Ticketing could equally look very different to most of today’s railway. McNaughton contends: “My starting position is not that you necessarily need advance booking - you don’t need advance booking to travel on Japanese Shinkansen, but you do need to have bought a ticket. And if you do need to buy a ticket, then one of the calls to be made is that traditionally in this country, on a traditional railway, you buy a ticket to travel. And you might or might not, although increasingly you do on long-distance, get a seat reservation.

“Similarly you buy a ticket to travel on EasyJet, you don’t buy a particular seat. But they don’t let on more people than there are seats. But why wouldn’t you buy a seat, rather than a particular journey? So, whether you’re doing it six months ahead, three months ahead or with five minutes to go, why wouldn’t you buy a seat?”

Quizzed on what a last-minute passenger prepared to take the risk of having to stand for the 49-minute journey to Birmingham might do, McNaughton says: “There’s a big issue with standing on high-speed trains, and the issue is about weight. So you don’t want a thousand seated and another 200 standing in the aisles because it’s Friday evening.

“So, subject to confirmation, because I wouldn’t want you to think a decision has been taken at this stage, the working assumption is that (so far) everybody that travels on High Speed 2 has a seat because they’ve purchased a seat. Which does not mean that you can’t turn up on Friday afternoon and purchase a ticket - you can, provided there’s a seat available to buy. If everyone has already bought all the seats, you’re not going to get on and hang off the luggage racks.”

Barring standing passengers is a step away from traditional UK rail practice. Only on Eurostar are you forced to book a seat (partly because Eurotunnel calculates Tunnel fees on the number of passengers a train carries).

As he claims: “There’s no reason, with modern technology, just because you’ve bought a seat on the 1615 two months ago, why you can’t change to the 1630 on the day. But the point is that you change your seat.

“If you’re travelling on Eurostar with a flexible ticket you still have to go and change your seat, you can’t just say that you have a ticket to ride today on the Eurostar. You can have flexibility within a modern system.

“The idea that you have a ticket is delightful, because when I travel I never travel without my boarding pass being on . A boarding pass is just a barcode, so why do you want a piece of paper? That’s quite relevant when you say: ‘how much room do you want for a ticket office?’ Ticket office? - that’s rather quaint. And that’s not knocking ticket office staff, but you’re just purchasing travel.

“If you go to Japan you just purchase it from a machine, but you can go to a ticket office if you don’t want to use a machine. So how much room do you have for machines. Or are people really going to purchase a ticket off a machine or just go ‘tappy, tappy, tappy’ and here’s my authority to travel. Because that’s all a ticket is, isn’t it?”

He’s getting into his stride now: “And so our system design has to accommodate a number of scenarios. From people saying ‘oh, tickets, that’s what granddad used to purchase’ through to people who actually like having a piece of paper that says you have seat 49 in coach 13 that you enter at gate 3, which is what I get when I go to the opera or to the match. I buy a seat and something that tells me how to get to it. Stand 6, entrance 2, stairway 4. Because, actually I can’t get to my seat if I go to stand 3.

“You don’t end-load Twickenham with 80,000 people and say the game starts in two minutes. You load it in each stand, and the ticket you have (your paper ticket) tells you which gate to go to and which coach to go to.

“Forget railways! This is 21st century long-distance travel. The challenges around a great number of people are to make it intuitively easy so that they don’t have to have been on a training course first to use it.

“So you design your physical infrastructure around people. They happen to end up sitting in a seat and something called a train, but that’s secondary to you conveying them from London to Manchester. You want to make it so easy that it’s not a problem. You don’t have to be 25 years old with a computer sciences degree and a laptop.”

That people are the key to the system came from two conversations. Both, McNaughton admits, led to ‘lightbulb moments’ of the real tasks that face HS2’s designers.

“The lightbulb moment came for a group of us when one of the senior vice presidents of Japan Central Railways asked: ‘do you have an asphalt trackbase or a concrete trackbase?’ and said: ‘well, that’s half of it, let’s talk about people - this is where all the challenges are’.

“Even on something like the Japanese high-speed railway, they never envisaged the number of people using it, and therefore they’ve had to back-engineer it.

“The other lightbulb moment was listening to Guillame Pepy , who said: ‘We’ve made many mistakes with French high-speed railways, and we’ve made many successes. The main mistake is not to think about the future - you design for today and design for today’s problem. Are you designing for tomorrow?’

“Tomorrow is, of course, a set of scenarios. Don’t foreclose on a scenario or a set of scenarios just be thinking about today. So you could easily get fixated on, say, ERTMS Level 2, but it could be that in 15 years’ time it might be that you say: ‘that’s the functionality, but we’ll operate it off the Tetra base’.

“Because Tetra might be a more effective way of getting from 2G to 4G . Who knows? I certainly don’t and I don’t think anybody else does. So we just make sure we design for (in our hybrid bill) operating off the Tetra system or a GSM-R system, or we could operate another system. So there could be a range of systems but we have the costs and the impacts and, frankly, whatever I think is the solution is probably wrong.”

The trackbed question raises another innovative development for new-build UK domestic railways, and how they are designed and built for ongoing maintenance and future renewals.

“The requirement on myself and my team from the sponsor - the Department for Transport - is a whole life railway, not just a first build. So design it so that it can be operated, maintained and renewed for its full life.

“You start to think about how you design, so that in that tunnel’s life you can replace all the M&E kit, and all the ventilation (because the ventilation is not going to last 120 years), without shutting the whole thing down for six months while you completely rebuild it.

“You have to think how to design a trackform that you build and renew at various times during its life. You have to design a control system that you undoubtedly will upgrade and replace a number of times.”

Asked if this has been done before in Britain, he answers: “Not explicitly, no,” before pausing for several seconds and adding: “I don’t think. There might be an element of it in Crossrail, but I’m not an expert in Crossrail.”

He continues: “I remember talking to the Japanese, for example, and asking, because they built metal bridges: ‘What happens when your bridges get to their fatigue life’? The answer was: ‘We build new railway.’

“The French have developed technology to renew track on their high-speed line without suspending services. The Japanese do track renewals on high-speed lines without suspending services. They’re not necessarily very cost-effective because they didn’t build that into the initial thinking, but it’s do-able.

“Ask the Germans how you renew slab track. If you start from scratch you can do it, because you effectively build pre-cast sections that you put on the base, and you can replace the pre-cast sections because you can lift them out. A bit like a model railway, because you lift the whole section out.”

Of course, this only works until you need to renew the base, which prompts McNaughton to admit: “Well, then it gets more difficult.”

Also difficult could be keeping a high-speed network punctual when it interacts with Network Rail’s tracks.

While it is pretty easy to see that trains could branch out from the London-West Midlands-Leeds/Manchester ‘Y network’ on time to continue their journeys to Newcastle or Edinburgh and Glasgow, for example, the opposite is not so clear-cut. It’s the hosepipe question: how do you get the water to spray into the nozzle of the hose?

It doesn’t faze McNaughton: “There are a number of different strategies to get the on-time railway coming the other way. Some people have talked of the need to have some sort of buffer timing. So you build a couple of three minutes in.

“It’s a bit like the old days when you approached the Channel Tunnel through Kent. If you were on time, you stood around for a couple of minutes; if you were a couple of minutes late then you went straight through the tunnel; and if you were ten minutes late you waited for the next path.

“So what we’re modelling is a series of slots reserved. But you also have the ability on a high-speed line to make trains go faster or slower, because you don’t timetable at full speed.

“This is very much the European way. So if the train arrives from Newcastle three minutes late onto the network somewhere near Leeds, can it make up those three minutes by the time it gets to the critical bit near Birmingham, where it joins the trunk? Or do we slow it by another two minutes, so that it’s five minutes late and it takes the next slot? It’s one of the advantages of a radio control system.

“It’s pure stacking theory. And you have absolutely real-time train planning. And if you’re going to run it six minutes later, can you still turn it round and get it out in time, or do you now run two trains five minutes late because you know you can do that? That’s the sort of real-time planning that in due course people will be doing.”

For now, though, McNaughton is concentrating on next year’s Hybrid Bill. It will not have all the answers and will not be a detailed blueprint for building High Speed 2.

He concludes: “You are presenting a credible set of assumptions, all of which produce a justification for taking a certain amount of land and having a certain amount of impact. You’re not designing the finished product.”

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