How long is a railway station platform?

Last Monday’s meltdown soured the return of trains after upgrades on the Dandenong and Frankston lines – which included works for the Metro tunnel, and also power upgrades extensions to some platforms.

So, how long is a railway station platform?

Generally, as long as the trains that serve it, plus a bit for spare.

There are exceptions, especially in regional areas of some countries, though this is rare in Victoria.

In Melbourne, suburban trains are currently standardised to 6 cars*:

  • Comeng 6 x 24 metres = 144 metres
  • Siemens 4 x 24.1 metres + 2 x 23.8 metres = 144 metres
  • X’Trapolis 4 x 24.46 metres + 2 x 22.76 metres = 143.36 metres

What about older trains?

Tait train (Steamrail Open Day 2014)

As early as 1908, and probably taking into account existing platform lengths, planning work for electrification determined that trains would be up to 6 carriages x 17.4 metres — the Tait (red) trains were built to this about length too.

Some then-existing shorter swing-door carriages were extended to that length, with trains being steam-hauled until each line was electrified. Information I’ve found is a little vague, but I believe with buffers/couplings the total carriage length was 18.81 metres, making a 6-car (electric) train 112.86 metres long.

Prior to that, trains had been various lengths, and the standardisation of lengths led to some lines getting more powerful steam locos, to cope with the additional weight, particularly on the hillier lines such as Ringwood and Hurstbridge.

In the 1920s, after electrification was completed, crowding resulted in extra carriages being added, making 7-car trains = 131.67 metres, requiring some platform extensions.

In the 1950s, Harris (blue trains) were introduced as 7-cars, with carriage lengths varying from 19.2 to 22.86 metres each. (Some of these still exist as V/Line’s aging “H” sets)

From 1967, some of the busiest lines ran as 8-cars during peak, to relieve crowding. I’m unclear of the precise carriages used in 8-car formations, but it would have meant trains at least around 154 metres long. This necessitated some platform extensions.

Platform measurements, Glenhuntly

From the 1970s, Hitachi trains were introduced, with longer carriages 23.41 metres long, of up to 6 cars = 140.46 metres, just slightly shorter than the current fleet.

The 1980s saw the 4D (double-deck) train trial. This was 4 x 20.32 metres = 81.28 metres, but if they’d ever got expanded to 8 cars, that would have been 162.56 metres. But in actual fact only 4 cars were ever built, and in peak they were connected to a 3-car Comeng set = 153.28 metres. It was decided they were unsuitable for Melbourne, and the cars were scrapped.

Still, the City Loop had been built to cater for a possible future roll-out of double-deck trains – both tunnel sizes, and platform lengths of about 160 metres. It wouldn’t surprise me if this was based on the standard Sydney double-deck train lengths of the 1960s, when the Loop was being designed.

Platform lengths grew with the train lengths, and at some stations it’s not hard to see how they’ve been extended over the years.

Today, new platforms are built as 160 metres, with the older existing platforms measuring around 150-160 metres, while most current trains are about 144 metres long.

In some spots, you can see where they’ve been measuring platforms to verify the length.

Glemhuntly platform 3 - measurements

The future?

And what about the future “High Capacity Metro Trains” (known as HCMTs for short – I think perhaps they need a snappier name). These are expected in service in 2019?

In their initial 7-car formation, these will be about 160 metres long.

With that length, they will just fit into the City Loop platforms, possibly with the rear cab out in the tunnel.

Part of the upgrade works underway to accommodate the new trains is improved power supply, facilitating not just the longer trains, but also more of them, with good reliability and enough juice that they can accelerate quickly. It was part of this that failed so spectacularly last Monday afternoon.

Extensions to some platforms have been needed.

  • South Yarra platform 6 and Caulfield platform 4 occurred last year.
  • During the early January works, South Yarra 5 and Caulfield 3 were also extended, though these don’t appear to be complete yet – at Caulfield there are still poles and signals in the way.
  • I haven’t gone looking recently, but presumably extensions are also underway at other older stations that need them between Caulfield and Cranbourne/Pakenham.
Caulfield platform 4 extension

10-car trains

In the future, the plan is to later go to 10-car HCMTs – about 230m long – on the Cranbourne/Pakenham to Sunbury line, via the new metro tunnel post-2025. Because underground platforms are very difficult to alter later, the tunnel stations are being designed with this in mind.

The newest skyrail stations have been built to 160m, but the LXRA tells me they have provision for 230m later, with straight sections beyond the current platforms, signal placements chosen carefully, and piers and foundations built so the new sections of platform can be slotted in with minimal disruption.

Older stations will no doubt be a lot trickier.

Hughesdale station looking east from the skyrail platform
Hughesdale station looking outbound

7-cars with the existing fleet?

I saw an idea proposed on Twitter: could they re-marshall the existing Comeng, X’Trapolis or Siemens fleet into 7-car trains?

It’s an interesting idea. But even assuming they’d have enough power (6-car Comeng trains for instance have four motor cars), they’d be at least 168 metres – too long for the City Loop platforms, which would be near-impossible to extend.

It would also cause problems in stabling yards, which would need re-design or alteration to cope with longer trains. This is why the HCMTs are getting a new maintenance and stabling facility near Pakenham.

What about other lines?

Lots of lines have crowding, and it appears all new station construction (such as the Mernda extension and other level crossing projects) has sensibly planned for 160 metres. So perhaps we can expect 7-car HCMTs eventually across the network. But it involves some big changes, so don’t hold your breath.

And longer trains aren’t the only answer. More trains is the other obvious solution to crowding, which includes:

  • more separation of lines to maximise track capacity and reduce flow-on effects of delays
  • smarter timetabling (consistent stopping patterns)
  • level crossing removals (to cut the impact on the road network as train services increase)
  • better signalling (such as in-cab high capacity signalling)
  • higher frequencies in shoulder-peak and off-peak, to help spread travel demand

Melbourne’s got busier, and is continuing to grow. We need all of this. Bring it on.

*Note that lengths for some models of train have varied, and the information I’ve found can be a little unclear as to whether measurements are rounded, and whether they include buffers/couplings and so on which would contribute to the total length of a train. So treat the above figures as a rough guide. Any corrections? Please let me know!