How did a single computer failure take out the whole of the Melbourne rail network?

Going nowhere fast. Image: Marcus Wong/Wikipedia Commons.

If you don’t live in Australia, then your only experience of Metro Trains Melbourne is probably the ghoulishly jolly Dumb Ways To Die animated clip that went viral in 2012. But, as the clip loosely implies, the group operates one of the southern hemisphere’s largest metro rail networks.

Or, if you were trying to travel Down Under this Thursday, it turned out that they didn’t. A reported computer failure first led to massive delays on the whole system, and eventually to the entire central part of the city’s network being brought to a total halt for several hours.

With thousands of commuters stuck in trains, drivers and guards pleaded with passengers not to force the train doors and escape into the danger of the tunnels (possibly via jolly songs). A desperate Twitter user held a poll on whether he should answer a call of nature through the emergency door; naturally Australia backed him with an 84 per cent Yes vote.

Train failures happen everywhere: signal failures, track failures, accidents, and incidents of all kinds are common annoyances for commuters. But the whole network collapsing due to a computer error seems a bit much: could they not just turn it off and start again…?

Basically, no.

The biggest problem here is that Melbourne has a single underground loop line that links all its suburban tracks together. It’s a bit like London Underground’s Circle/District/Metropolitan/Hammersmith lines, with the crucial difference that almost all Melbourne’s suburban trains go at least partially round the loop – there’s no other route through the city. Even the city’s two terminus stations, Southern Cross and Finders Street, form part of the city loop, and many terminating services share signalling systems with loop trains.

A schematic of the Melbourne city loop. Source: Wikipedia.

Like many rail systems, Melbourne’s was randomly constructed by private companies out for a cheap buck, with no interest in interconnected metro or in buying up expensive city blocks to build through-lines. The city’s flat, swampy land also put everyone off tunnelling.

A lot of mergers and some nationalisation later, the system found itself feeding into two main terminals, both overcrowded. By 1969, transport planners decided that this wouldn’t do, and planned the City Loop.

Planners love joining up suburban lines with a tunnel through the city. You replace two busy, land-scarce, crowded terminals with through stations, serve major city destinations directly, and only have to turn trains around in the sticks. The RER in Paris, London’s Thameslink and Crossrail, and Berlin’s HBF all work on this principle.

But Melbourne’s planners were… braver.

Remember, every train into Melbourne already went into either Southern Cross (then called Spencer Street) or Flinders Street. Building the loop wasn’t like building Crossrail: it was like building a mash-up of Crossrail, Thameslink and the Overground to carry every single train that previously used to go into a London terminus.


The planners rose to the challenge: the number of tracks on the circle varies from two to six (originally planned as four to eight). But the net result was to create a complicated service with a lot of junctions and crossovers, which needs to carry lots of trains.

They had a clever solution to the complexity, too: they built one of the world’s first computerised railways. The City Loop opened in 1980 with fully automated signalling, using a dedicated system called Metrol, which allowed faster, more reliable switching, signaller and passenger information. When it opened, this was a state of the art system.

The trouble is, almost 40 years and some privatisation later, franchise operator Metro Trains Melbourne and government infrastructure owner Public Transport Victoria are still using it.

The brains of the system have been moved from the original ancient PDP-11 mainframes to a network of PC servers, and some modern train control systems have been added; but it’s still based around 40-year-old software, and the interface between the new computers and the tracks and signals still relies on 40-year-old interface boards. Metro Trains has to acquire replacements on the second-hand market as other companies retire their old servers.

Using old equipment isn’t rare in transport. New York’s still running on kit that was 40 years old when Metrol was installed, and the systems being removed in London are even older. Although the dreaded ‘signal failure’ is a common reason for scraping along at snail’s pace, they don’t halt the whole system.

But… well, have you tried watching an analogue versus a digital TV with a bad signal? Old-style train control systems are dumb, often fail, and are designed for the failures to be local and worked around. When newer-style train control systems fail, because the brains are centralised, so is the crash. More recent ones are designed to route around these problems, but Melbourne led the way and paid the price.

The complete system map. Click to expand. Image: Melbourne Metro.

Worse still, in other major cities, if a signal failure takes out one line, then you’ve still got a bunch of other lines to use. The City Loop means you can’t do that in Melbourne: if you lose signalling here, then every train line in the city is stuffed. Although the Metrol system only covers the City Loop and a few neighbouring inner suburban stations, you can’t run trains in the suburbs if they’re stuck on the wrong side of the city.

So what can Melbourne do? Replacing Metrol is often discussed, but would be painfully expensive, especially in terms of the disruption caused – and more recently, modern information systems have been built on top of it, which you’d have to fit in with the replacement.

The government are also starting work on a new tunnelled line through the CBD that's completely independent from the loop, which will help take some of the pressure off services – but even when it’s done, most city lines will still be subject to the same problems.

If I were Public Transport Victoria or Metro Trains, as the old joke says, I wouldn’t want to be starting from here.

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Joe Anderson: Why I resigned from the Northern Powerhouse Partnership

Liverpool Lime Street station, 2008. Image: Getty.

The Labour mayor of Liverpool has a few choice words for Chris Grayling.

I resigned from the board of the Northern Powerhouse Partnership this week. I just didn’t see the point of continuing when it is now crystal clear the government isn’t committed to delivering the step-change in rail investment in the North that we so desperately need. Without it, the Northern Powerhouse will remain a pipedream.

Local government leaders like me have been left standing at the altar for the past three years. The research is done. The case has been made. Time and again we’ve been told to be patient – the money is coming.

Well, we’ve waited long enough.

The only thing left is for the transport secretary to come up with the cash. I’m not holding my breath, so I’m getting on with my day job.

There’s a broader point here. Rail policy has been like a roller-coaster in recent years. It soars and loops, twisting and turning, without a clear, committed trajectory. There is no consistency – or fairness. When London makes the case for Crossrail, it’s green-lit. When we make the same case for HS3 – linking the key Northern cities – we are left in Whitehall limbo.

Just look at the last week. First we had the protracted resignation of Sir Terry Morgan as Chairman of HS2 Ltd. Just when we need to see firm leadership and focus we have instead been offered confusion and division. His successor, Allan Cooke, said that HS2 Ltd is “working to deliver” services from London to Birmingham – the first phase of the line – from 2026, “in line with the targeted delivery date”. (“In line?”)

Just when HS2 finally looked like a done deal, we have another change at the top and promises about delivery are sounding vaguer. Rumours of delays and cost over-runs abound.

Some would like to see the case for HS2 lose out to HS3, the cross-Pennine east-west line. This is a bit like asking which part of a train is more important: its engine, or its wheels. We need both HS2 and HS3. We are currently left trying to build the fourth industrial revolution on infrastructure from the first.

If we are ever to equip our country with the ability to meet rising customer and freight demand, improve connectivity between our major conurbations and deliver the vision of the Northern Powerhouse, then we need the key infrastructure in place to do that.


There are no shortcuts. Ministers clearly believe there are. The second piece of disappointing news is that officials at the Department for Transport have already confirmed to the freight industry that any HS3 line will not be electrified, the Yorkshire Post reports.

This is a classic false economy. The renaissance of the Liverpool Dockside – now called Superport – is undergoing a £1bn investment, enabling it to service 95 per cent  of the world’s largest container ships, opening up faster supply chain transit for at least 50 per cent  of the existing UK container market. Why squander this immense opportunity with a cut-price rail system?

Without the proper infrastructure, the North of England will never fulfil its potential, leaving our economy lop-sided and under-utilised for another generation. This is not provincial jealousy. Building a rail network that’s fit for purpose for both passenger and freight will remove millions of car journeys from the road and make our national economy more productive. It will also be cleaner, cheaper and more reliable. Our European neighbours have long understood the catalytic effect of proper connectivity between cities.

Similarly, linking together towns and key cities across the North of England is a massive prize that will boost growth, create jobs and provide a counterweight to Greater London, easing pressures on the capital and building resilience into our national economy.

To realise this vision, we need the finance and political commitment. Confirmation that the government is pushing ahead with HS3 – as well as HS2 – is now sorely needed.

With Brexit looming and all the uncertainly it brings in its wake, it is even more pressing to have clarity around long-term investment decisions about our critical infrastructure. Given the investment, the North will seize the chance.

But until ministers are serious, I have a city to run.

Joe Anderson is the elected Labour mayor of Liverpool.