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0 pointsdkdbejwi3831y ago0 comments

Acceleration etc wouldn't really matter if I live at one end of the line and my friend lives at the opposite end. It would be an annoyingly long journey that stops at every single other station in the entire city.

In a regular city that grows outwards, you'd expect there to be circumferential routes as well as cross-city routes connecting various points, making the travel time more bearable.

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saberience1y ago

I sort of assume they would have express trains as well as local trains, a bit like the NY subway. I.e. one train which just goes direct to the other end with no stops at high speed.

pndy1y ago

Wikipedia article mentions "the Spine" - an underground tunnel that would host transport superfast train infrastructure connecting both sides of the complex. Traveling from one end to another would take 20mins, supposedly.

ta12431y ago

So about as long as riding a bike from anywhere in a equivalent sized normal city to another point (6km tops)

keiferski1y ago

It would matter if an express train could accelerate fast enough to make the end-to-end trip quicker than a cross-city trip in a typical city.

ta12431y ago

No.

With no top speed, accelerate for 85km at 1m/s then decelerate for the next 85km/s at 1m/s and that's about 13 minutes with a top speed of about 900mph. 1m/s is the top acceleration you can have for a typical passenger train for comfort purposes.

Total area of a 170km*200m city is 34 square km, or a city about 6.5km across.

London's Elizabeth line (crossrail) covers a distance of 6.75km from Paddington to Liverpool Street in 11 minutes, with 3 intermediate stops.

The circumference of a 6.5km diameter city would be 20km. 20 cross-city lines with decent headway and interchange would give a worst case journey of

- 250m to nearest station - 3 minutes walk

- 2 minute wait for train

- 5 minutes to central station

- 200m/3 minutes to appropiate platform

- 2 minute wait for train

- 5 minutes to destination station

- 200m/3 minutes to destination

25 minutes. From anywhere to anywhere.

j / k navigate · click thread line to collapse

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saberience1y ago

I sort of assume they would have express trains as well as local trains, a bit like the NY subway. I.e. one train which just goes direct to the other end with no stops at high speed.

pndy1y ago

ta12431y ago

So about as long as riding a bike from anywhere in a equivalent sized normal city to another point (6km tops)

keiferski1y ago

It would matter if an express train could accelerate fast enough to make the end-to-end trip quicker than a cross-city trip in a typical city.

ta12431y ago

No.

Total area of a 170km*200m city is 34 square km, or a city about 6.5km across.

London's Elizabeth line (crossrail) covers a distance of 6.75km from Paddington to Liverpool Street in 11 minutes, with 3 intermediate stops.

The circumference of a 6.5km diameter city would be 20km. 20 cross-city lines with decent headway and interchange would give a worst case journey of

- 250m to nearest station - 3 minutes walk

- 2 minute wait for train

- 5 minutes to central station

- 200m/3 minutes to appropiate platform

- 2 minute wait for train

- 5 minutes to destination station

- 200m/3 minutes to destination

25 minutes. From anywhere to anywhere.

j / k navigate · click thread line to collapse