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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What it's been like living in one of the few places that never locked down

People enjoy sunny weather in Tantolunden park in Stockholm on May 30, 2020, amid the novel coronavirus pandemic. (Henrik Montgomery/TT News Agency/AFP via Getty Images)

While most of the Western world was confined to their homes for the better part of two months this spring, my friends and I in Stockholm continued hanging out. In stark contrast to most other places, we went to restaurants (occasionally, outside when possible), to one another’s houses (in our yards when possible), and even sent our kids to school. As the rest of the world opens up again, not much will change in Stockholm.

As an American expat living in the Swedish capital, I was initially angry at Sweden’s response to the Covid-19 pandemic. In my home country, early outbreaks in locations such as Seattle, New York City and the San Francisco Bay Area led to strict rules that were soon mirrored in many other states and cities. The Swedish strategy, meanwhile, boiled down mostly to recommendations: If possible, work from home; avoid unnecessary travel within the country; engage in social distancing; and if you’re above 70, stay home. I felt that, in the face of a global pandemic, a country known for its generous welfare policies – that took such good care of its citizens – wasn’t doing its part to protect us.

My friends and I are mostly expats with young families who, early on, pulled our children out of school against official policy. (Schools here only closed for those 16 and over.) We eagerly waited to hear what further action our current country would take. Surely a country known for its progressive social policies would take fast, decisive action to protect its citizens?

The regulations that were put into place in Sweden amounted to restricting public gatherings to no more than 50 people (reduced from 500, which concert halls skirted by restricting entry to 499), limiting restaurants to table service only, and no visiting retirement homes. People here did take the work-from-home guidelines to heart – no one I knew was going in to work. But bars and restaurants were full. My Instagram feed was a highlight reel of acquaintances clinking champagne flutes at the city’s major clubs and restaurants.

After the first few weeks, I slowly started meeting up with friends again. I sent my kids back to school, where they intentionally spent most of the day outdoors and drop-offs were restricted to outside only (parents weren’t allowed to enter the building). I was careful to take precautions like bringing hand sanitizer to playgrounds and wiping my hands after opening and closing the gate to school. Hardly anyone wore masks to the grocery shop or inside stores – the few times I’ve seen people wearing them I’ve done a double take. One busy Friday night in late April at the local supermarket there was a line out the door and someone regulating the number of customers allowed inside at the same time. I took a photo and sent it to my family in the US saying “Sweden finally catching up with the rest of the world!” (I haven’t seen entry to that store being regulated since.)

When I spoke to Swedish friends about the strategy many agreed with the relaxed approach, mentioning that other countries’ draconian measures would be unnecessary in Sweden. A recent poll showed that just 11% of people in Sweden felt they did not trust state epidemiologist Anders Tegnell, who is leading the strategy. In this country, the onus was placed on citizens themselves to follow recommendations. It's about personal judgement and individual responsibility within a framework that rested on mutual trust, rather than top-down control. Swedes’ high level of interpersonal trust and trust in authority was often cited in the press as the characteristic enabling the relaxed Swedish strategy in tackling the virus, as opposed to social distancing becoming a matter of surveillance and policing like in Spain or Italy, where any nonessential socializing was forbidden.

In early May, Sweden's ambassador to the US Karin Ulrika Olofsdotter said in an interview with the Washington Post that some media outlets made it look “like everyone in Sweden is out drinking and partying,” she said. “That is not the case.” But that was certainly how it felt to me. According to research by Esteban Ortiz-Ospina and Max Roser in 2016, in countries such as Norway, Sweden and Finland, more than 60% of respondents in the World Value Survey think that people can be trusted. And in the other extreme, in countries such as Colombia, Brazil, Ecuador and Peru, less than 10% think that this is the case.


Of course, many places in the US also took a similarly relaxed approach to tackling the pandemic, with conservative lawmakers and anti-lockdown activists citing Sweden as taking the right approach. Sweden, rarely finding cheerleaders among conservative US circles, suddenly stood as an example to follow. But since then, places such as Arizona, Texas and Florida have all seen significant spikes in cases following reopenings and are being deemed the new epicentres of the virus – while Sweden’s numbers have stabilised. According to some reports, the death toll in Sweden is one of the highest in the world per capita, but the total number of Swedish deaths remains at just above 5,000, compared to over 120,000 in the US, over 43,000 in the UK, over 28,000 in Spain and over 34,000 in Italy. The mortality rate in Sweden and the number of new intensive care cases in the country declined in the last week and contagion rates here are now “stable” according to the WHO.

Although it didn’t always feel like it at the time, Sweden issued clear guidance from the beginning, with the expectation that people would choose to follow it. It certainly was my experience that everyone I knew stopped going into the office and started working from home. William Hanage, an associate professor of epidemiology at Harvard’s School of Public Health, attributed Sweden’s slowing of the virus to implementing guidance early on. “Sweden’s policy is unusual in that it took a much less stringent approach to preventing transmission," he says, "but interestingly it implemented those measures at a very early stage in the pandemic, before large amounts of community spread had occurred.”

Now I go outside and all too often realise I’ve left my hand sanitiser at home. I even met a friend for lunch outdoors at a busy cafe one particularly sunny day, and another indoors one Friday night for dinner. In May I had a birthday bash in my garden with a dozen or so friends and we ended up at the local bar. I always felt guilty after, as if I’d done something wrong that I couldn’t tell my family in Baltimore about. When I watched international news or spoke to family back home I would feel a certain cognitive dissonance between my own seemingly low-risk reality and what I knew to be happening in the rest of the world. My family in the US calls me skeptically questioning why I’ve had people over in my garden, or been out to eat. I can’t explain the lack of logic that permits an entire city’s citizens to operate life as normal in the midst of a global pandemic. But Stockholm has become a bubble of exactly this.

Being relatively young and healthy, I’m not so worried about getting sick. Even though young and healthy people have gotten seriously ill, there haven’t been any reported cases at my kids’ or any of my friends’ kids’ schools. Nobody I know in Stockholm knows has gotten sick, allowing me to feel a certain distance from it. But my husband’s parents are in their mid-70s and weren’t able to see their grandchildren for two months save for a few visits to their hallway, where we wave and blow kisses to them standing at the door.

I’ve been grateful – but also felt a sense of guilt for – my freedom here. When there are no hard and fast rules about how to act, it’s easy to constantly question yourself: Is it really okay to be outside, sitting at this full cafe? Is it okay to invite a few friends over for a birthday? Is it okay to send my kids to school? These questions have surely gone through minds around the world in the past several weeks, and now it’s clear that that behaviour had dire consequences in some cities and not others.

While Swedish social media at times suggests an endless friend-filled party at summer homes and popular hangouts, the reality here is a balancing act between personal judgement and the freedom to continue life as normal. Self-regulation is what it comes down to in Sweden, anyway.

Elysha Krupp is a writer and editor currently living in Stockholm.