3 ms·

What about short distances? Why is it cheaper to fly Berlin-Stuttgart than to take a train? it makes absoutely no sense.

londons_explore 3mo ago
Trains are expensive because the track is 99.9% empty. If you could fill a train track as much as a road is filled, it would be very cheap
- dredmorbius 3mo ago
  Track utilisation is limited by a number of factors, including headways, much of which is governed by stopping distance. I believe a general minimum practical headway allows about 10--12 trainsets per hour on a given track. At 400 passengers/trainset, that's roughly 4,000 to 4,800 passengers/hour, per track. That compares with about 1,500 vehicles/hour per highway lane, or about 2,550 passengers/hour at the U.S. average of 1.7 passengers/vehicle. I've seen some suggestion that headways could be reduced to 3--4 minutes, or 15--20 trainsets/hour. I know that some urban rapid transit systems (e.g., BART in San Francisco) achieve this, but only on a small section of the system (Colma to Oakland, transiting downtown SF, IIRC). Train speeds there peak at 70 MPH, and I believe are much slower for most of this portion of track.
  - londons_explore 3mo ago
    Some urban subways have 30 second headways.
    - dredmorbius 3mo ago
      And, I suspect, low speeds, as braking distance increases with the square of speed. The New York subway has a top speed of 55 mph (88 kmh), but an average speed of 17.8 mph (28 kmh). I'm not sure what downtown intra-station peaks are, but suspect they're low on shorter sections. The London Underground is similar, with an average of 33 kmh (20 mph), max ~100 kmh (60 mph). This varies considerably by lines, the Bakerloo stock peaks at 45 mph; the Circle line averages just 24 kmh (15 mph). Chicago's 'L' is similar to NYC: max 55 mph, average ~20--25 mph.[3] Note that averages include acceleration, deceleration, and dwell times (standing still at stations). But central portions of subways probably achieve low headways with relatively low peak speeds for congested track segments. Notes: ________________________________ 1. <https://parkingday.org/how-fast-do-new-york-subway-trains-travel/ https://parkingday.org/how-fast-do-new-york-subway-trains-tr...> 2. <https://tubenotifications.co.uk/insights/how-fast-is-the-tube https://tubenotifications.co.uk/insights/how-fast-is-the-tub...> 3. <https://parkingday.org/how-fast-does-the-subway-go-in-chicago/ https://parkingday.org/how-fast-does-the-subway-go-in-chicag...>
elil17 3mo ago
The costs are pretty evenly split between: 1) Maintaining track 2) Buying/leasing/maintaining trains 3) Staff The single best thing you can do to drive down train cost is to put more people on each train. Based on these sources: https://www.statista.com/chart/20169/gb-rail-fare-spending-breakdown/?srsltid=AfmBOorwmz_TStNJqvm7KTAVfKdGXBG7BdsGvpgy2uRBcDDW2I2TqVC4 https://www.statista.com/chart/20169/gb-rail-fare-spending-b... https://transport.ec.europa.eu/document/download/f5c82d86-2351-4e16-a082-727f419e1bc7_en?filename=2015-09-study-on-the-cost-and-contribution-of-the-rail-sector-exec-summary_en.pdf https://transport.ec.europa.eu/document/download/f5c82d86-23...
- dudefeliciano 3mo ago
  I understand where the costs come from, but how trains are more expensive to operate than airplanes is still baffling to me.

londons_explore 3mo ago

Trains are expensive because the track is 99.9% empty. If you could fill a train track as much as a road is filled, it would be very cheap

dredmorbius 3mo ago
Track utilisation is limited by a number of factors, including headways, much of which is governed by stopping distance. I believe a general minimum practical headway allows about 10--12 trainsets per hour on a given track. At 400 passengers/trainset, that's roughly 4,000 to 4,800 passengers/hour, per track. That compares with about 1,500 vehicles/hour per highway lane, or about 2,550 passengers/hour at the U.S. average of 1.7 passengers/vehicle. I've seen some suggestion that headways could be reduced to 3--4 minutes, or 15--20 trainsets/hour. I know that some urban rapid transit systems (e.g., BART in San Francisco) achieve this, but only on a small section of the system (Colma to Oakland, transiting downtown SF, IIRC). Train speeds there peak at 70 MPH, and I believe are much slower for most of this portion of track.
- londons_explore 3mo ago
  Some urban subways have 30 second headways.
  - dredmorbius 3mo ago
    And, I suspect, low speeds, as braking distance increases with the square of speed. The New York subway has a top speed of 55 mph (88 kmh), but an average speed of 17.8 mph (28 kmh). I'm not sure what downtown intra-station peaks are, but suspect they're low on shorter sections. The London Underground is similar, with an average of 33 kmh (20 mph), max ~100 kmh (60 mph). This varies considerably by lines, the Bakerloo stock peaks at 45 mph; the Circle line averages just 24 kmh (15 mph). Chicago's 'L' is similar to NYC: max 55 mph, average ~20--25 mph.[3] Note that averages include acceleration, deceleration, and dwell times (standing still at stations). But central portions of subways probably achieve low headways with relatively low peak speeds for congested track segments. Notes: ________________________________ 1. <https://parkingday.org/how-fast-do-new-york-subway-trains-travel/ https://parkingday.org/how-fast-do-new-york-subway-trains-tr...> 2. <https://tubenotifications.co.uk/insights/how-fast-is-the-tube https://tubenotifications.co.uk/insights/how-fast-is-the-tub...> 3. <https://parkingday.org/how-fast-does-the-subway-go-in-chicago/ https://parkingday.org/how-fast-does-the-subway-go-in-chicag...>

elil17 3mo ago

The costs are pretty evenly split between: 1) Maintaining track 2) Buying/leasing/maintaining trains 3) Staff The single best thing you can do to drive down train cost is to put more people on each train. Based on these sources: https://www.statista.com/chart/20169/gb-rail-fare-spending-breakdown/?srsltid=AfmBOorwmz_TStNJqvm7KTAVfKdGXBG7BdsGvpgy2uRBcDDW2I2TqVC4 https://www.statista.com/chart/20169/gb-rail-fare-spending-b... https://transport.ec.europa.eu/document/download/f5c82d86-2351-4e16-a082-727f419e1bc7_en?filename=2015-09-study-on-the-cost-and-contribution-of-the-rail-sector-exec-summary_en.pdf https://transport.ec.europa.eu/document/download/f5c82d86-23...

dudefeliciano 3mo ago
I understand where the costs come from, but how trains are more expensive to operate than airplanes is still baffling to me.