4 ms·

Is this why so many city metro subways have flat faces? I've always wondered why so many are not aerodynamic in the slightest.

kpil 8y ago
They don't move that fast, so saving space is more important. Not perhaps at the stations but at rail yards and transfers that might be underground.
- fyfy18 8y ago
  In the UK most trains are fairly flat faced, however trains travel relatively slowly (compared to Europe) at a typical maximum of 100mph. https://en.m.wikipedia.org/wiki/British_Rail_Class_450 https://en.m.wikipedia.org/wiki/British_Rail_Class_450
  - Symbiote 8y ago
    That's essentially a local or regional train. Attaching multiple trains together and still allowing people to walk through is important. Many local trains in Europe have a similar design, and a similar top speed. The long distance trains in the UK do go faster and have an angled front. It's presumable a trade off between aerodynamics and walk-through ability when connecting trains.
    - fyfy18 8y ago
      This specific configuration is for a commuter train, but similar trains (which can be coupled to other sets) are used on long distance routes in the UK. As I said, the UK isn't really high speed compared to Europe. Other than the Eurostar line/HS1, all other lines throughout the UK are limited to 140mph (225km/h) or less.
  - dukoid 8y ago
    I think an escape path in tight tunnels is the main concern for this design in the UK...
larkeith 8y ago
Do the aerodynamics work the same in an enclosed tunnel? Presumably at a certain point it matters less that the face isn't aerodynamic, but I've no idea how that scales.
hudibras 8y ago
It's for driver visibility.
mjg59 8y ago
Largely flexibility - you can build consists that contain multiple driver cars and still allow passengers to move between them, and then you can split them up and rearrange them without having to remove and reattach separate cars first. BART actually switched from angled front cars to flat front ones when they increased their fleet size, and converted a bunch of the angled ones (some were kept for effectively PR reasons). But the alternative is that you're losing space, since the maximum length of a car is determined by the track geometry and clearance of the system. Anything other than a flat fronted car is reducing volume available for passengers.
deleted 8y ago
[deleted]
Reason077 8y ago
On metro systems (especially older ones) there are often tight constraints on train length, so that they can fit between sets of signals or points without fouling them, for example. Pointy aerodynamic noses increase train length without increasing passenger capacity. Generally you want to maximise capacity while staying within the maximum allowed train length.

kpil 8y ago

They don't move that fast, so saving space is more important. Not perhaps at the stations but at rail yards and transfers that might be underground.

fyfy18 8y ago
In the UK most trains are fairly flat faced, however trains travel relatively slowly (compared to Europe) at a typical maximum of 100mph. https://en.m.wikipedia.org/wiki/British_Rail_Class_450 https://en.m.wikipedia.org/wiki/British_Rail_Class_450
- Symbiote 8y ago
  That's essentially a local or regional train. Attaching multiple trains together and still allowing people to walk through is important. Many local trains in Europe have a similar design, and a similar top speed. The long distance trains in the UK do go faster and have an angled front. It's presumable a trade off between aerodynamics and walk-through ability when connecting trains.
  - fyfy18 8y ago
    This specific configuration is for a commuter train, but similar trains (which can be coupled to other sets) are used on long distance routes in the UK. As I said, the UK isn't really high speed compared to Europe. Other than the Eurostar line/HS1, all other lines throughout the UK are limited to 140mph (225km/h) or less.
- dukoid 8y ago
  I think an escape path in tight tunnels is the main concern for this design in the UK...

larkeith 8y ago

Do the aerodynamics work the same in an enclosed tunnel? Presumably at a certain point it matters less that the face isn't aerodynamic, but I've no idea how that scales.

hudibras 8y ago

It's for driver visibility.

mjg59 8y ago

Largely flexibility - you can build consists that contain multiple driver cars and still allow passengers to move between them, and then you can split them up and rearrange them without having to remove and reattach separate cars first. BART actually switched from angled front cars to flat front ones when they increased their fleet size, and converted a bunch of the angled ones (some were kept for effectively PR reasons). But the alternative is that you're losing space, since the maximum length of a car is determined by the track geometry and clearance of the system. Anything other than a flat fronted car is reducing volume available for passengers.

deleted 8y ago

[deleted]

Reason077 8y ago

On metro systems (especially older ones) there are often tight constraints on train length, so that they can fit between sets of signals or points without fouling them, for example. Pointy aerodynamic noses increase train length without increasing passenger capacity. Generally you want to maximise capacity while staying within the maximum allowed train length.