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The article talks about a train that can go 200mph. That makes having people drive between cities seem a rather slow option. Plus you can get work done on a tra

The article talks about a train that can go 200mph. That makes having people drive between cities seem a rather slow option. Plus you can get work done on a train. On a car it is not possible as a driver (other than phone calls) and pretty hard as a passenger. I take your point about planes, but it's good to have more than one option and trains are good for middling distances, as there isn't all the need to check in, and they can start and stop closer to where you want to depart from and arrive. Not to mention global warming :-)

shdh 8y ago
Why just 200mph
- kingosticks 8y ago
  Because it's here today. It's easy with simple investment, it's got huge benefits over the joke that is the current U.S train service.
  - grecy 8y ago
    There are plenty of passenger trains in service around the world that go faster than 200mp/h, today.
    - bobthepanda 8y ago
      Those are all in China. Wikipedia tells me that max achievable speed in regular service in every country except China is 320km/h. China does 350km/h, but you need to be traveling at quite a long distance for a measly 30km/h increase in speed to be worth it, and China runs much longer high speed rail services than other countries (Beijing to Hong Kong is 9 hours). Besides, the more important thing is average speed. Acela's top speed is respectable for legacy rail, but it achieves this top speed for a total of 33 miles over a 457 mile route.
      - grecy 8y ago
        > Those are all in China You're probably right. America shouldn't aim to achieve speeds of high speed rail in ~2025 that China achieved in ~2015. That's aiming too high. Best to aim lower so we don't disappoint anyone.
        innocenat 8y ago
        And China pretty much stopped running train at 350km/h. Steel-on-steel rail is realistically limited to top service speed of 320km/h, maybe 360 at most. The maintenance is just too high when you increase speed beyond that. Newer Japanese Shinkansen line only operate at 260km/h, for example.
        bobthepanda 8y ago
        The most painful part of high-speed-rail, particularly at higher speeds, is the land acquisition costs; minimum curve radius grows exponentially as speed rises, so costs escalate as speed gets higher. China cares far less about compensating property owners for fair value, which is why they can engineer such high speed lines in the first place. We are talking about the difference between 217MPH and 200MPH. The total travel time saved between Boston and Washington by an additional 17MPH is a whopping six minutes with the generous assumption that you start right off the bat at top speed and maintain it the entire trip. If saving six minutes will cost billions or tens of billions of dollars, why bother with such a marginal improvement, when you could spend those billions on literally anything else from housing to healthcare to upgrading the power grid?
    - kingosticks 8y ago
      Yes, but the US just needs a taste to get going. They don't need to aim too high, they should concentrate on delivering something.
- bobthepanda 8y ago
  As you increase speed, you need to take turns at larger and larger curves to reduce g-forces on passengers, and the curve radius increases exponentially vs speed. The bigger the curve, the more land you need to buy, and depending on which country you're in property rights extend above and below the land so the cost is unavoidable. (If you can avoid it by going underground or overground, the cost of tunneling and bridges is expensive.) It becomes increasingly costly to increase speed, and on top of that you get diminishing returns with travel time (speeding up from 80 to 120MPH is worth a lot more than going from 200MPH to 240MPH). And above a certain point you spend too much time accelerating and decelerating from top speed, and not enough time actually at the top speed to make it all worthwhile. Regardless of motive technology, curve-radius will always be a relevant problem, because one of the major advantages of the train is that you can walk around and about. We could design trains with sharper corners and harder acceleration/deceleration, but no one wants to be strapped into a vomit comet for three hours.
  - the8472 8y ago
    > and the curve radius increases exponentially vs speed. It's merely quadratic if I recall correctly
    - bobthepanda 8y ago
      Oops, I misspoke. But yeah, it's a non-linear increase in costs that results in increasingly marginal time savings.
trhway 8y ago
Instead of trains we're working on self driving cars. They better serve last mile and are better suited for private investment and innovation than huge infrastructure projects.
- xg15 8y ago
  Can you work in them without getting sick?
- bobthepanda 8y ago
  The self driving car can't go 200MPH. You also can't fit as many people in self driving cars, simply because having the requisite fuel storage and engine per 2-4 seater car is quite a lot of space when you can spread that around 200 people per train car. And this is before we consider that average car occupancy is something like 1.5.

shdh 8y ago

Why just 200mph

kingosticks 8y ago
Because it's here today. It's easy with simple investment, it's got huge benefits over the joke that is the current U.S train service.
- grecy 8y ago
  There are plenty of passenger trains in service around the world that go faster than 200mp/h, today.
  - bobthepanda 8y ago
    Those are all in China. Wikipedia tells me that max achievable speed in regular service in every country except China is 320km/h. China does 350km/h, but you need to be traveling at quite a long distance for a measly 30km/h increase in speed to be worth it, and China runs much longer high speed rail services than other countries (Beijing to Hong Kong is 9 hours). Besides, the more important thing is average speed. Acela's top speed is respectable for legacy rail, but it achieves this top speed for a total of 33 miles over a 457 mile route.
    - grecy 8y ago
      > Those are all in China You're probably right. America shouldn't aim to achieve speeds of high speed rail in ~2025 that China achieved in ~2015. That's aiming too high. Best to aim lower so we don't disappoint anyone.
      - innocenat 8y ago
        And China pretty much stopped running train at 350km/h. Steel-on-steel rail is realistically limited to top service speed of 320km/h, maybe 360 at most. The maintenance is just too high when you increase speed beyond that. Newer Japanese Shinkansen line only operate at 260km/h, for example.
      - bobthepanda 8y ago
        The most painful part of high-speed-rail, particularly at higher speeds, is the land acquisition costs; minimum curve radius grows exponentially as speed rises, so costs escalate as speed gets higher. China cares far less about compensating property owners for fair value, which is why they can engineer such high speed lines in the first place. We are talking about the difference between 217MPH and 200MPH. The total travel time saved between Boston and Washington by an additional 17MPH is a whopping six minutes with the generous assumption that you start right off the bat at top speed and maintain it the entire trip. If saving six minutes will cost billions or tens of billions of dollars, why bother with such a marginal improvement, when you could spend those billions on literally anything else from housing to healthcare to upgrading the power grid?
  - kingosticks 8y ago
    Yes, but the US just needs a taste to get going. They don't need to aim too high, they should concentrate on delivering something.
bobthepanda 8y ago
As you increase speed, you need to take turns at larger and larger curves to reduce g-forces on passengers, and the curve radius increases exponentially vs speed. The bigger the curve, the more land you need to buy, and depending on which country you're in property rights extend above and below the land so the cost is unavoidable. (If you can avoid it by going underground or overground, the cost of tunneling and bridges is expensive.) It becomes increasingly costly to increase speed, and on top of that you get diminishing returns with travel time (speeding up from 80 to 120MPH is worth a lot more than going from 200MPH to 240MPH). And above a certain point you spend too much time accelerating and decelerating from top speed, and not enough time actually at the top speed to make it all worthwhile. Regardless of motive technology, curve-radius will always be a relevant problem, because one of the major advantages of the train is that you can walk around and about. We could design trains with sharper corners and harder acceleration/deceleration, but no one wants to be strapped into a vomit comet for three hours.
- the8472 8y ago
  > and the curve radius increases exponentially vs speed. It's merely quadratic if I recall correctly
  - bobthepanda 8y ago
    Oops, I misspoke. But yeah, it's a non-linear increase in costs that results in increasingly marginal time savings.

trhway 8y ago

Instead of trains we're working on self driving cars. They better serve last mile and are better suited for private investment and innovation than huge infrastructure projects.

xg15 8y ago
Can you work in them without getting sick?
bobthepanda 8y ago
The self driving car can't go 200MPH. You also can't fit as many people in self driving cars, simply because having the requisite fuel storage and engine per 2-4 seater car is quite a lot of space when you can spread that around 200 people per train car. And this is before we consider that average car occupancy is something like 1.5.