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What would it take to reduce the cost of maglev trains? Perhaps 300 mph trains would be enough to convince Americans to take a train. UPDATE Just answer my q

What would it take to reduce the cost of maglev trains? Perhaps 300 mph trains would be enough to convince Americans to take a train. UPDATE Just answer my question instead of trying to explain that people won’t take trains.

otabdeveloper4 3y ago
Trains compete with cars, not airplanes. Focus on price and comfort, because raw speed doesn't matter here much.
- melling 3y ago
  I guess you could just answer my question instead of digressing. Trains do compete with planes. Consider San Francisco to Los Angeles, for example. That’s about 9 million people a year who fly? It’s only 400 miles. New York to Boston. Washington DC to New York. When you’re traveling 300 miles an hour, you can get pretty far in two to three hours.
  - ghaff 3y ago
    Acela is already pretty competitive with flying. I never fly that route unless I'm connecting to another plane. It's a horrible drive (although, given where I live, driving would be faster). And getting into Manhattan from the airports is pretty horrible too. But it would be a huge cost to shave an hour off the route. As it is, I tend to take the regional train rather than the Acela if it's my own money because the time difference isn't much and the cost is about 2x.
    - melling 3y ago
      Acela between NY and Boston is great. Taken it several times. However, if you do the math, Acela averages about 85 mph.
  - flomo 3y ago
    > Consider San Francisco to Los Angeles, for example. That’s about 9 million people a year who fly? It’s only 400 miles. California has already done a lot of the engineering analysis for this one. They need to build like a hundered tunnels through mountain ranges, seismic rifts, and mansion districts. It's great planning businesses for the consultants, but it is way too expensive to ever be constructed. Much cheaper to fly over all of that, rather than go under it.
    - 3D30497420 3y ago
      I don't know details on how CA compares to Italy, but Italy has built a very good high-speed network. A sizable portion of it is through fairly mountainous, very seismically active, pretty populated regions. I recently took the Frecciarossa from Bologna to Florence and was really looking forward to sitting back and enjoying the view of the Italian countryside. Instead, you spend most of your time going through tunnels, with the occasional quick glimpse of the countryside out the window. Milan to Rome is about ~350 miles (580 km) and the train takes about 3 hours, compared to a ~6 hour drive. I believe this is about the same distance from LA to SF.
      - flomo 3y ago
        You can fly from LA to SF in 30 minutes. Even with all the airport security theater, CAHSR's hundreds of planned tunnels will not be competitive for business travelers. The premise is more about people wanting to go to Fresno.
    - delta_p_delta_x 3y ago
      > mountain ranges, seismic rifts, and mansion districts Have they consulted Japan, which has successfully built HSR through precisely the same sort of terrain, geophysical, and human limitations that California appears to have, including being on some of the most seismically active places on the planet? I swear, Americans have some sort of bipolar disorder when it comes to high speed rail. They love the concept of it, but when it comes to actually implementing it, nothing actually gets done, or people complain that 'it's going to be too expensive' or 'America is too big' or 'we have seismic zones'. It's very hilarious and a bit sad, looking in from the outside. For the record, urban rapid transit is no better. New York City (and maybe San Francisco) being the exception, essentially every other large American city has nearly non-existent public transport. European cities are significantly better, and East/Southeast Asian ones (HK, Tokyo, Seoul, Singapore) are in a completely different league altogether.
  - powersnail 3y ago
    Tangentially, as an alternative to planes and trains, you can take a bus from SF to LA. A bit clammy, tough.
- 3D30497420 3y ago
  It depends. In some cases I believe they certainly do. One of the reasons cited for the demise of Alitalia was the development of Italy's high speed train network, which is very good and quite extensive. I think speed is important, it does get tiring to sit on a train for 8 or 10 hours compared to a 1.75 hour flight. However, it is certainly one factor and how it compares to other modes of transport will depend on the person and situation.
ghaff 3y ago
Which Americans? Busses are probably almost certainly going to be cheaper given existing highway and other road infrastructure that isn't going away. So now we're talking about wealthier people and (somewhat overlapping) business travelers who tend to value comfort, convenience, and schedule to at least some degree over cost. Never say never but it seems a tough sell for most city pairings/routes given that just acquiring land would be a huge cost even if everything else were free.
- melling 3y ago
  My question is, what would it take to reduce the cost of maglev trains. China has tried, but they are expensive. Japan is building an expensive maglev over the next couple decades.
  - ghaff 3y ago
    The actual answer is that you just take people's property without compensation or with well below market compensation. (And throw out any requirements for Environmental Impact Statements.) That's where the cost savings would be. I don't actually favor that to be clear. Building the actual structures has cost but it's probably not where the bulk of the costs are.
    - melling 3y ago
      No, it’s the bike shedding that people do. They can’t actually answer the question so they digress and discuss something else. I guess you wanna talk about property rights?
      - devman0 3y ago
        I guess it depends on how you are defining "costs" in the question. Costs due to regulatory/legal requirements are a huge part of why these projects are expensive in addition to actual track, trainsets, civil engineering, etc that go in to these projects.
lmm 3y ago
Speed isn't the issue, you need to make the cities convenient to those without cars. Long-distance trains have a huge natural benefit in running directly from city centre to city centre, but that's basically negated if people can't get around those city centres without hiring a car or expensive cabs. Pedestrianise your city centres, build decent commuter transit networks, and long distance trains will follow.
- melling 3y ago
  Listening to Americans discussing trains is painful. China built 25,000 miles of high-speed rail in the time the United States has built zero. Yes, I understand that it’ll never work in America. Now, can you just answer my question: what would it take to reduce the cost of maglevs trains? The use case is for China to build its next 25,000 miles of HSR with maglevs
  - xeromal 3y ago
    You seem unreasonably sore. lol
  - lmm 3y ago
    > China built 25,000 miles of high-speed rail in the time the United States has built zero. And note that despite operating the most successful maglev in the world since 2004, they decided not to build any more. While building more maglevs would probably bring the cost down some, it's fundamentally expensive technology that delivers very marginal benefit compared to "conventional" wheel-on-rail HSR, which can achieve almost the same speed with much less infrastructure.
    - melling 3y ago
      Hence, my question about reducing the cost of maglevs. China is pursuing low-speed maglevs that run about 100 mph and are much cheaper. http://www.xinhuanet.com/english/2020-12/15/c_139591288.htm http://www.xinhuanet.com/english/2020-12/15/c_139591288.htm Japan is proceeding and will open something by the end of the decade https://eandt.theiet.org/content/articles/2023/04/japanese-maglev-line-unlikely-to-meet-2027-opening-date/ https://eandt.theiet.org/content/articles/2023/04/japanese-m...
rjzzleep 3y ago
The Shinkansens drive at around 300km/h. It's fast enough to get you from east to west-coast in 15 hours. It's a 6-7 hour flight + 2-3 hours airport shenanigans. The problem is that there is no capability to build such infrastructure anymore. Neither in the US, nor in Europe. It requires both political will and construction companies that build public infrastructure without being political party operatives. EDIT: sorry I meant to write km/h, that's why the calculation is correct at 15 hours => 4668/300.
- ghaff 3y ago
  That understates travel time though. e.g. Tokyo to Osaka is about 250 miles and takes about 2.5 hours via Shinkansen. So it's more like 100 mph on average with stops. And, unless it's a lot cheaper, no one is taking a 20+ hour train trip instead of a 6 hour flight unless it's for the scenery, etc. I allow about 90 minutes at the typical airport for the 15 minutes through security and the buffer. Maybe new train tech can deliver higher speeds but, as part one of the article noted, you can't just eliminate stops and they can slow down the average speed a lot.
  - PaulDavisThe1st 3y ago
    You can eliminate the stops with station loops, but that's Advanced Magic. Ironically, the vast emptiness of North America would actually work in favor of these little lovelies much better than in Europe or Asia.
  - kristopolous 3y ago
    Trains are quite a bit less hassle than flights. I can buy the ticket the day of without it popping to some ridiculous price. I can take a train leaving at any time. I've got plenty of room. There's no large list of luggage size and weight rules, onerous security, and all that other nonsense. The fact that I literally do not have to think about the train and just go, with basically the same convenience as say driving a car and I get free fast wifi, cell signal, plenty of space to do work, comfortable seats even at the basic price ... even slow high speed rail between SF and LA I'd take every time, hands down. No question. If it was actually decent modern high speed (300mph+) I'm never looking back. Although knowing the US, it'll probably be some kind of perverse inconvenient complicated time consuming hellish nightmare
imgabe 3y ago
Americans do take trains when they’re affordable and convenient. The NE corridor in Amtrak is heavily used even with all its problems. You don’t have to come up with some crazy new innovation for Mag-Lev, just make the trains reliable, affordable, and near major population centers.
- idontwantthis 3y ago
  SD <-> LA is also a lovely ride. Makes it feel like you're in one big city. Takes more than 2 hours, but it's city center to city center, and trains are so much more comfortable than any alternative.
  - melling 3y ago
    That’s 120 miles. Sometime in the future that’ll be commutable by maglev. Here are a few other commutable routes with maglev NYC - Philly 92 miles NYC - DC 225 miles NYC - Boston 215 miles NYC - Portland, ME 325 miles NYC - Pittsburgh 380 miles NYC - Cleveland 470 miles Cleveland - Chicago 350 miles St. Louis - Chicago 320 miles Houston - Dallas 240 miles Houston - Austin 170 miles Dallas - Austin 200 miles Seattle - Portland 175 miles Las Vegas - Los Angeles 280 miles
    - gaadd33 3y ago
      People already commute via trains from NYC to Philly, no need to maglev to make it reasonable. Some of the other ones (NYC to Pittsburgh for example) run into the same issues with maglev as normal rails do, namely geography. But it would be great if all of those were connected by regular 200mph rails, 300mph maglev would be even better. I don't think there's the appetite for the level of investment either one would take.
- ghaff 3y ago
  >near major population centers One of the advantages of trains is that there can be train stations convenient to where people go within the city whereas airports are often hell and gone. There are more light rails etc. than there used to be but Manhattan, for example, is terrible for getting into the city from any of the airports. Both Logan in Boston and National in DC are pretty good. LA is sort of a , sorry, train wreck (or at least very variable) for getting around without a car. SF is better the airport is actually at least as good (via BART) getting into the city as the Amtrak station in Emeryville is. People use commuter rail in Boston, NYC, etc. too but it's generally less useful (or not useful at all) outside of commuting.
addicted 3y ago
The only way to reduce the costs of Maglevs is to build a lot more Maglevs. However, it’s not necessary that there actually are significant economies of scale to be achieved with Maglev. But the bigger issue is that it’s not clear why anyone outside of Japan would even build Maglev at the moment. For obvious reasons, faster speed only becomes advantageous beyond a certain distance. But pretty much every country in the world has city pairs where HSR isn’t built out and the distances are too short for Maglev to be built. Any country trying to go in for a high speed transit option is likely to connect these city pairs first before they try city pairs at greater distances where Maglev may actually make sense even ignoring cost. So you’re unlikely to see a mass rollout of Maglev for decades, so the actual correct answer is that what you need to make Maglev more cost efficient is a few decades and economies of scale.
andbberger 3y ago
maglevs have an existential capacity issue because the switches take so long. there's a ways to go to push the speed of steel-on-steel trains yet
bruce511 3y ago
You asked a legitimate question, and also came to a conclusion. Your conclusion is easy to refute, hence you got most replies there. I'll focus on your question. The short answer is "everything". Let's start either public desire. Nobody wants a 300mph train to go through their neighborhood. Especially a train they'll likely never ride. One that doesn't stop locally. Since public interactions are an important part of any major project in the US this has a real cost implication. Equally public perception en masse leads to the project becoming political, so it can't fly under the radar. (It benefits at least some politicians to be anti so they're anti regardless of merit.) Get past the people, and you get into the environment. Long distance trains cover a Lot of land so lots and lots on environmental impact studies to do. So you're spending mountains of cash before you can even be assured the project will happen. Because its such high risk, that cash comes very expensive. (Politically expensive if its public funds, commercially expensive if its loans or investments. ) If you got this far, construction is expensive because you're not just "laying track". Everything you touch will be subject to a million local regulations, which will differ from one county to the next. You will need an army of lawyers, inspectors, endless tweaks here and there, and so on. The trains will be expensive. Any craft travelling at 300mph will necessarily be expensive. You'll want it to be safe, which means (quite reasonably) this is not an area to be cheap. You specified maglev, but that is almost the least interesting part. All the above applies to any rail project. Maglev adds to the cost primarily in terms of tech, and the results of tech failing. (The train would need to safely transition between maglev and not maglev, at 300mph). So, to answer your question, you need to ignore the public, ignore the environment, ignore the effect of public opinion on politicians, ignore local regulations, be able to aquire land (in a straight line) without hindrance, and of course source a cheap train. And at the end of it? Maybe you'll have a train people will ride. Maybe you won't. (For reasons mentioned elsewhere in this thread, I'm guessing won't).
- PaulDavisThe1st 3y ago
  > Nobody wants a 300mph train to go through their neighborhood And yet somehow, that's what the rest of the world is trying to build, through neighborhoods. Le me guess, American Exceptionalism once more, eh? > The trains will be expensive. Any craft travelling at 300mph will necessarily be expensive. Checked out the cost of Airbus and Boeing's most recent offerings?
scythe 3y ago
Either much better superconductor performance at 78 K (instead of the more common 4 K) or much cheaper permanent magnets (the "Inductrack" configuration). Permanent magnet EDS has a risk problem: contamination of the magnet will incur an extremely expensive repair (the field cannot be deactivated), and putting together a vehicle containing lots of very strong permanent magnets is logistically challenging (to put it mildly!). AFAIK all existing maglev is superconducting EDS. The same issue limits the use of permanent magnet MRI. But new permanent magnets are a lot more foreseeable than new superconductors, since at least there are some candidate possibilities for magnets (Fe16N2 and L10-FeNi) while the plan for better superconductors currently relies on star charts and prayers. You could also come up with a way to make Litz wire without copper, but again that's very blue-sky and you'd have to make enough of it to build a whole railroad. The tl;dr is that according to physics, making stuff float is hard.

otabdeveloper4 3y ago

Trains compete with cars, not airplanes. Focus on price and comfort, because raw speed doesn't matter here much.

melling 3y ago
I guess you could just answer my question instead of digressing. Trains do compete with planes. Consider San Francisco to Los Angeles, for example. That’s about 9 million people a year who fly? It’s only 400 miles. New York to Boston. Washington DC to New York. When you’re traveling 300 miles an hour, you can get pretty far in two to three hours.
- ghaff 3y ago
  Acela is already pretty competitive with flying. I never fly that route unless I'm connecting to another plane. It's a horrible drive (although, given where I live, driving would be faster). And getting into Manhattan from the airports is pretty horrible too. But it would be a huge cost to shave an hour off the route. As it is, I tend to take the regional train rather than the Acela if it's my own money because the time difference isn't much and the cost is about 2x.
  - melling 3y ago
    Acela between NY and Boston is great. Taken it several times. However, if you do the math, Acela averages about 85 mph.
- flomo 3y ago
  > Consider San Francisco to Los Angeles, for example. That’s about 9 million people a year who fly? It’s only 400 miles. California has already done a lot of the engineering analysis for this one. They need to build like a hundered tunnels through mountain ranges, seismic rifts, and mansion districts. It's great planning businesses for the consultants, but it is way too expensive to ever be constructed. Much cheaper to fly over all of that, rather than go under it.
  - 3D30497420 3y ago
    I don't know details on how CA compares to Italy, but Italy has built a very good high-speed network. A sizable portion of it is through fairly mountainous, very seismically active, pretty populated regions. I recently took the Frecciarossa from Bologna to Florence and was really looking forward to sitting back and enjoying the view of the Italian countryside. Instead, you spend most of your time going through tunnels, with the occasional quick glimpse of the countryside out the window. Milan to Rome is about ~350 miles (580 km) and the train takes about 3 hours, compared to a ~6 hour drive. I believe this is about the same distance from LA to SF.
    - flomo 3y ago
      You can fly from LA to SF in 30 minutes. Even with all the airport security theater, CAHSR's hundreds of planned tunnels will not be competitive for business travelers. The premise is more about people wanting to go to Fresno.
  - delta_p_delta_x 3y ago
    > mountain ranges, seismic rifts, and mansion districts Have they consulted Japan, which has successfully built HSR through precisely the same sort of terrain, geophysical, and human limitations that California appears to have, including being on some of the most seismically active places on the planet? I swear, Americans have some sort of bipolar disorder when it comes to high speed rail. They love the concept of it, but when it comes to actually implementing it, nothing actually gets done, or people complain that 'it's going to be too expensive' or 'America is too big' or 'we have seismic zones'. It's very hilarious and a bit sad, looking in from the outside. For the record, urban rapid transit is no better. New York City (and maybe San Francisco) being the exception, essentially every other large American city has nearly non-existent public transport. European cities are significantly better, and East/Southeast Asian ones (HK, Tokyo, Seoul, Singapore) are in a completely different league altogether.
- powersnail 3y ago
  Tangentially, as an alternative to planes and trains, you can take a bus from SF to LA. A bit clammy, tough.
3D30497420 3y ago
It depends. In some cases I believe they certainly do. One of the reasons cited for the demise of Alitalia was the development of Italy's high speed train network, which is very good and quite extensive. I think speed is important, it does get tiring to sit on a train for 8 or 10 hours compared to a 1.75 hour flight. However, it is certainly one factor and how it compares to other modes of transport will depend on the person and situation.

ghaff 3y ago

Which Americans? Busses are probably almost certainly going to be cheaper given existing highway and other road infrastructure that isn't going away. So now we're talking about wealthier people and (somewhat overlapping) business travelers who tend to value comfort, convenience, and schedule to at least some degree over cost. Never say never but it seems a tough sell for most city pairings/routes given that just acquiring land would be a huge cost even if everything else were free.

melling 3y ago
My question is, what would it take to reduce the cost of maglev trains. China has tried, but they are expensive. Japan is building an expensive maglev over the next couple decades.
- ghaff 3y ago
  The actual answer is that you just take people's property without compensation or with well below market compensation. (And throw out any requirements for Environmental Impact Statements.) That's where the cost savings would be. I don't actually favor that to be clear. Building the actual structures has cost but it's probably not where the bulk of the costs are.
  - melling 3y ago
    No, it’s the bike shedding that people do. They can’t actually answer the question so they digress and discuss something else. I guess you wanna talk about property rights?
    - devman0 3y ago
      I guess it depends on how you are defining "costs" in the question. Costs due to regulatory/legal requirements are a huge part of why these projects are expensive in addition to actual track, trainsets, civil engineering, etc that go in to these projects.

lmm 3y ago

Speed isn't the issue, you need to make the cities convenient to those without cars. Long-distance trains have a huge natural benefit in running directly from city centre to city centre, but that's basically negated if people can't get around those city centres without hiring a car or expensive cabs. Pedestrianise your city centres, build decent commuter transit networks, and long distance trains will follow.

melling 3y ago
Listening to Americans discussing trains is painful. China built 25,000 miles of high-speed rail in the time the United States has built zero. Yes, I understand that it’ll never work in America. Now, can you just answer my question: what would it take to reduce the cost of maglevs trains? The use case is for China to build its next 25,000 miles of HSR with maglevs
- xeromal 3y ago
  You seem unreasonably sore. lol
- lmm 3y ago
  > China built 25,000 miles of high-speed rail in the time the United States has built zero. And note that despite operating the most successful maglev in the world since 2004, they decided not to build any more. While building more maglevs would probably bring the cost down some, it's fundamentally expensive technology that delivers very marginal benefit compared to "conventional" wheel-on-rail HSR, which can achieve almost the same speed with much less infrastructure.
  - melling 3y ago
    Hence, my question about reducing the cost of maglevs. China is pursuing low-speed maglevs that run about 100 mph and are much cheaper. http://www.xinhuanet.com/english/2020-12/15/c_139591288.htm http://www.xinhuanet.com/english/2020-12/15/c_139591288.htm Japan is proceeding and will open something by the end of the decade https://eandt.theiet.org/content/articles/2023/04/japanese-maglev-line-unlikely-to-meet-2027-opening-date/ https://eandt.theiet.org/content/articles/2023/04/japanese-m...

rjzzleep 3y ago

The Shinkansens drive at around 300km/h. It's fast enough to get you from east to west-coast in 15 hours. It's a 6-7 hour flight + 2-3 hours airport shenanigans. The problem is that there is no capability to build such infrastructure anymore. Neither in the US, nor in Europe. It requires both political will and construction companies that build public infrastructure without being political party operatives. EDIT: sorry I meant to write km/h, that's why the calculation is correct at 15 hours => 4668/300.

ghaff 3y ago
That understates travel time though. e.g. Tokyo to Osaka is about 250 miles and takes about 2.5 hours via Shinkansen. So it's more like 100 mph on average with stops. And, unless it's a lot cheaper, no one is taking a 20+ hour train trip instead of a 6 hour flight unless it's for the scenery, etc. I allow about 90 minutes at the typical airport for the 15 minutes through security and the buffer. Maybe new train tech can deliver higher speeds but, as part one of the article noted, you can't just eliminate stops and they can slow down the average speed a lot.
- PaulDavisThe1st 3y ago
  You can eliminate the stops with station loops, but that's Advanced Magic. Ironically, the vast emptiness of North America would actually work in favor of these little lovelies much better than in Europe or Asia.
- kristopolous 3y ago
  Trains are quite a bit less hassle than flights. I can buy the ticket the day of without it popping to some ridiculous price. I can take a train leaving at any time. I've got plenty of room. There's no large list of luggage size and weight rules, onerous security, and all that other nonsense. The fact that I literally do not have to think about the train and just go, with basically the same convenience as say driving a car and I get free fast wifi, cell signal, plenty of space to do work, comfortable seats even at the basic price ... even slow high speed rail between SF and LA I'd take every time, hands down. No question. If it was actually decent modern high speed (300mph+) I'm never looking back. Although knowing the US, it'll probably be some kind of perverse inconvenient complicated time consuming hellish nightmare

imgabe 3y ago

Americans do take trains when they’re affordable and convenient. The NE corridor in Amtrak is heavily used even with all its problems. You don’t have to come up with some crazy new innovation for Mag-Lev, just make the trains reliable, affordable, and near major population centers.

idontwantthis 3y ago
SD <-> LA is also a lovely ride. Makes it feel like you're in one big city. Takes more than 2 hours, but it's city center to city center, and trains are so much more comfortable than any alternative.
- melling 3y ago
  That’s 120 miles. Sometime in the future that’ll be commutable by maglev. Here are a few other commutable routes with maglev NYC - Philly 92 miles NYC - DC 225 miles NYC - Boston 215 miles NYC - Portland, ME 325 miles NYC - Pittsburgh 380 miles NYC - Cleveland 470 miles Cleveland - Chicago 350 miles St. Louis - Chicago 320 miles Houston - Dallas 240 miles Houston - Austin 170 miles Dallas - Austin 200 miles Seattle - Portland 175 miles Las Vegas - Los Angeles 280 miles
  - gaadd33 3y ago
    People already commute via trains from NYC to Philly, no need to maglev to make it reasonable. Some of the other ones (NYC to Pittsburgh for example) run into the same issues with maglev as normal rails do, namely geography. But it would be great if all of those were connected by regular 200mph rails, 300mph maglev would be even better. I don't think there's the appetite for the level of investment either one would take.
ghaff 3y ago
>near major population centers One of the advantages of trains is that there can be train stations convenient to where people go within the city whereas airports are often hell and gone. There are more light rails etc. than there used to be but Manhattan, for example, is terrible for getting into the city from any of the airports. Both Logan in Boston and National in DC are pretty good. LA is sort of a , sorry, train wreck (or at least very variable) for getting around without a car. SF is better the airport is actually at least as good (via BART) getting into the city as the Amtrak station in Emeryville is. People use commuter rail in Boston, NYC, etc. too but it's generally less useful (or not useful at all) outside of commuting.

addicted 3y ago

The only way to reduce the costs of Maglevs is to build a lot more Maglevs. However, it’s not necessary that there actually are significant economies of scale to be achieved with Maglev. But the bigger issue is that it’s not clear why anyone outside of Japan would even build Maglev at the moment. For obvious reasons, faster speed only becomes advantageous beyond a certain distance. But pretty much every country in the world has city pairs where HSR isn’t built out and the distances are too short for Maglev to be built. Any country trying to go in for a high speed transit option is likely to connect these city pairs first before they try city pairs at greater distances where Maglev may actually make sense even ignoring cost. So you’re unlikely to see a mass rollout of Maglev for decades, so the actual correct answer is that what you need to make Maglev more cost efficient is a few decades and economies of scale.

andbberger 3y ago

maglevs have an existential capacity issue because the switches take so long. there's a ways to go to push the speed of steel-on-steel trains yet

bruce511 3y ago

You asked a legitimate question, and also came to a conclusion. Your conclusion is easy to refute, hence you got most replies there. I'll focus on your question. The short answer is "everything". Let's start either public desire. Nobody wants a 300mph train to go through their neighborhood. Especially a train they'll likely never ride. One that doesn't stop locally. Since public interactions are an important part of any major project in the US this has a real cost implication. Equally public perception en masse leads to the project becoming political, so it can't fly under the radar. (It benefits at least some politicians to be anti so they're anti regardless of merit.) Get past the people, and you get into the environment. Long distance trains cover a Lot of land so lots and lots on environmental impact studies to do. So you're spending mountains of cash before you can even be assured the project will happen. Because its such high risk, that cash comes very expensive. (Politically expensive if its public funds, commercially expensive if its loans or investments. ) If you got this far, construction is expensive because you're not just "laying track". Everything you touch will be subject to a million local regulations, which will differ from one county to the next. You will need an army of lawyers, inspectors, endless tweaks here and there, and so on. The trains will be expensive. Any craft travelling at 300mph will necessarily be expensive. You'll want it to be safe, which means (quite reasonably) this is not an area to be cheap. You specified maglev, but that is almost the least interesting part. All the above applies to any rail project. Maglev adds to the cost primarily in terms of tech, and the results of tech failing. (The train would need to safely transition between maglev and not maglev, at 300mph). So, to answer your question, you need to ignore the public, ignore the environment, ignore the effect of public opinion on politicians, ignore local regulations, be able to aquire land (in a straight line) without hindrance, and of course source a cheap train. And at the end of it? Maybe you'll have a train people will ride. Maybe you won't. (For reasons mentioned elsewhere in this thread, I'm guessing won't).

PaulDavisThe1st 3y ago
> Nobody wants a 300mph train to go through their neighborhood And yet somehow, that's what the rest of the world is trying to build, through neighborhoods. Le me guess, American Exceptionalism once more, eh? > The trains will be expensive. Any craft travelling at 300mph will necessarily be expensive. Checked out the cost of Airbus and Boeing's most recent offerings?

scythe 3y ago

Either much better superconductor performance at 78 K (instead of the more common 4 K) or much cheaper permanent magnets (the "Inductrack" configuration). Permanent magnet EDS has a risk problem: contamination of the magnet will incur an extremely expensive repair (the field cannot be deactivated), and putting together a vehicle containing lots of very strong permanent magnets is logistically challenging (to put it mildly!). AFAIK all existing maglev is superconducting EDS. The same issue limits the use of permanent magnet MRI. But new permanent magnets are a lot more foreseeable than new superconductors, since at least there are some candidate possibilities for magnets (Fe16N2 and L10-FeNi) while the plan for better superconductors currently relies on star charts and prayers. You could also come up with a way to make Litz wire without copper, but again that's very blue-sky and you'd have to make enough of it to build a whole railroad. The tl;dr is that according to physics, making stuff float is hard.