Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Map Shows Where 220mph Trains Would Go in the U.S.

mashable.com

Post reply on HN
Print view View original

31–40 of 75 posts

Re: Map Shows Where 220mph Trains Would Go in the U.S.

#31

Post by jellicle »

uvdiv wrote: post #8
rayiner wrote: post #7

Earlier quoted context omitted.

The idea that in 20 years we'll have self-driving cars on any substantial scale is totally ridiculous. If I had to bet money, we won't even have a substantial electric car deployment by then, much less self-driving cars. Also: the physics of high-speed cars makes the concept of cars traveling as fast as bullet trains totally ridiculous. The fact that a car is self-driving doesn't change the physics of tire/road frict…

Also: the physics of high-speed cars makes the concept of cars traveling as fast as bullet trains totally ridiculous. The fact that a car is self-driving doesn't change the physics of tire/road friction. Friction losses aren't significant. These cars are limited by aerodynamic drag power -- this scales as speed^3, and dominates all other losses.

Friction losses aren't significant. These cars are limited by aerodynamic drag power -- this scales as speed^3, and dominates all other losses.

No.

"Of the energy output of fuel in a car engine, 33% is spent in exhaust, 29% in cooling and 38% in mechanical energy, of which friction losses account for 33% and air resistance for 5%. By comparison, an electric car has only half the friction loss of that of a car with a conventional internal combustion engine."

So, meh, even if magic self-driving cars had zero air resistance, they're only 5% more efficient than non-self-driving cars.

Re: Map Shows Where 220mph Trains Would Go in the U.S.

#32

Post by kristopolous »

rayiner wrote: post #13
tunesmith wrote: post #6

So there's this puzzle that people enjoy thinking about regarding space travel. Say that it finally becomes possible to reach a planet of a nearby star. It's a new technology that enables it, and we can build a spaceship that will support several generations of people during the trip. Maybe it takes 500 years to get there. Well, 500 years is a long time. It's not as if our technological development will stop in the m…

Infrastructure technology progresses extremely slowly, in a way I think is hard for people used to the progress in computer technology to understand. Most electricity in the U.S. is still produced by coal power, in plants that usually aren't dramatically more efficient than they were a century ago. 2050 is 37 years from now. 37 years ago was 1976. Most of the transit infrastructure we use today was already built by 1…

That's because americans drag their feet. Look at what happened to ShangHai in 20 years: http://www.businessinsider.com/shanghai-1990-vs-2010-2010-6

Or Dubai in 17: http://www.ebaumsworld.com/pictures/view/187773/

Or (in the US): South (new) Las Vegas: http://earthobservatory.nasa.gov/IOTD/view.php?id=37228

Or take the 1994 LA Earthquake where the freeways were repaired 2.5 months early: http://articles.latimes.com/1994-04-06/news/mn-42778_1_santa...

Or you can even go 150 years back to when the London Sewage System was built, http://en.wikipedia.org/wiki/London_sewerage_system in a matter of a few years

Or Chongqing: http://forum.skyscraperpage.com/showthread.php?t=172962 ... their rivers glisten brown with progress (I guess)

Or take the Chinese High Speed Rail which went from 0 KM in 2007 to 9300 KM in 2012.

Or take the German Autobahn which went from 108 KM to 3736 KM between 1935 and 1940.

Re: Map Shows Where 220mph Trains Would Go in the U.S.

#33

Post by trevorstrohman »

lutusp wrote: post #9
tunesmith wrote: post #6

So there's this puzzle that people enjoy thinking about regarding space travel. Say that it finally becomes possible to reach a planet of a nearby star. It's a new technology that enables it, and we can build a spaceship that will support several generations of people during the trip. Maybe it takes 500 years to get there. Well, 500 years is a long time. It's not as if our technological development will stop in the m…

But the argument for high-speed rail isn't that it will serve as a stopgap measure until we have self-driving cars, it is that a railroad train is vastly more efficient than any imaginable car technology. Railroad trains are very energy-efficient, compared to cars driving along a road, or even trucks driving along a road. And if we suddenly had self-driving cars, packed close together and safer than the existing syst…

The Wikipedia article shows that passenger trains use about 35% less energy per passenger/mile than the average car. If fuel efficiency for cars rose to 40 mpg (less than a Prius), they'd be equivalent.

Re: Map Shows Where 220mph Trains Would Go in the U.S.

#34

Post by newbie12 »

jarcoal wrote: post #24
newbie12 wrote: post #18

First we need to fix regular passenger rail in this country. As long as interstate passenger rail is controlled by the Amtrak monopoly, and its attendant unions, rail travel in America will continue to fall behind the rest of the world. There's not even regular rail service between most major US cities 3-8 hours apart, even though tracks exist and demand would exist if trains ran as fast as driving.

Freight is a big problem. They own the rails; Amtrak is a guest.

That's only partially true-- Amtrak owns the Northeast corridor. Amtrak's only innovation in forty years (!) on the NEC is Acela, a "high speed" offering that is marginally faster than regular service (shorter times mainly because Acela makes fewer stops) and is more expensive than private air shuttle travel along the same routes.

Re: Map Shows Where 220mph Trains Would Go in the U.S.

#35

Post by skcin7 »

I'm all for a HSR system and I think it sounds AWESOME, but I have doubts if it would ever catch on.

HSR would have to compete with the current airline system. If it's cheaper, more convenient to ride, and the time required to travel is comparable to airline, it could catch on, but as it stands I'm unsure if there's enough room for it to survive while competing against the airline system.

Commercial airlines travel at around 500-600 miles per hour, so if a HSR system is able to reach 220mph, then the plane will get you there about ~2.5x as fast. Of course. People consider their time to be valuable, so if you need to get somewhere quick, you'd likely just take the airplane, unless you're traveling somewhat nearby (like San Francisco to Los Angeles). It would appeal to most people not having to deal with the TSA, but there's no guarantee TSA wouldn't decide that it's their duty to "protect" (terrorize) the people in the HSR system as well.

Somebody please write me a message to convince me my message is nonsense and that a HSR system is a great idea.

Re: Map Shows Where 220mph Trains Would Go in the U.S.

#36

Post by bjelkeman-again »

rayiner wrote: post #13
tunesmith wrote: post #6

So there's this puzzle that people enjoy thinking about regarding space travel. Say that it finally becomes possible to reach a planet of a nearby star. It's a new technology that enables it, and we can build a spaceship that will support several generations of people during the trip. Maybe it takes 500 years to get there. Well, 500 years is a long time. It's not as if our technological development will stop in the m…

Infrastructure technology progresses extremely slowly, in a way I think is hard for people used to the progress in computer technology to understand. Most electricity in the U.S. is still produced by coal power, in plants that usually aren't dramatically more efficient than they were a century ago. 2050 is 37 years from now. 37 years ago was 1976. Most of the transit infrastructure we use today was already built by 1…

The infrastructure debt in the US is huge and it gets harder and harder every year to catch up. The idea that self driving cars, as some seem to argue below this post, will somehow solve this infra debt is IMHO just plain uninformed. The Economist sets the underinvestment at $94 billion / year.

If the US doesn't sort this out it will have a significant impact in growth in the future. You can maybe see some of the effects of this already in the faster moving Internet infrastructure.

Re: Map Shows Where 220mph Trains Would Go in the U.S.

#37

Post by pyre »

tunesmith wrote: post #6

So there's this puzzle that people enjoy thinking about regarding space travel. Say that it finally becomes possible to reach a planet of a nearby star. It's a new technology that enables it, and we can build a spaceship that will support several generations of people during the trip. Maybe it takes 500 years to get there. Well, 500 years is a long time. It's not as if our technological development will stop in the m…

Are these self-driving cars expected to organize themselves into 'trains' that go 220mph or am I missing something?

Also, w.r.t. the spaceship, what happens if the time between the tech for spaceship #1 and the tech for spaceship #2 includes an extinction-level event? Why build spaceship #2 when we can just wait another couple hundred years and assume that obviously we will improve it even more?

Why buy a new computer when it will be obsolete within a couple of months? I should just never buy a new computer and then I will never have to worry about it being obsolete!

Re: Map Shows Where 220mph Trains Would Go in the U.S.

#38

Post by jarcoal »

newbie12 wrote: post #34
jarcoal wrote: post #24

Earlier quoted context omitted.

Freight is a big problem. They own the rails; Amtrak is a guest.

That's only partially true-- Amtrak owns the Northeast corridor. Amtrak's only innovation in forty years (!) on the NEC is Acela, a "high speed" offering that is marginally faster than regular service (shorter times mainly because Acela makes fewer stops) and is more expensive than private air shuttle travel along the same routes.

Ah yes, I've heard of that train. It doesn't go any faster than 100mph does it?

Re: Map Shows Where 220mph Trains Would Go in the U.S.

#39

Post by thrownaway2424 »

Hilarious comparison with the self-driving cars. The whole POINT of a train is you arrive in an actual PLACE. Not some god-forshaken dump surrounded by parking lots.

In 2011 I was in Zurich during "street parade" which is one of those crazy european things where lots of people gather to dance to awful music. Anyway, the attendance was nearly a million. Substantially all of these million people arrived by train in the six hours before noon on the day of the event. I was flabbergasted watching these people pour out of the rail station by the thousand. This is totally impossibile by road.

The contest between trains and cars is not about the way people get around. It is about the way they live when they are not moving. Trains enable the kinds of cities people want to visit. Cars hollow out and destroy cities.

Re: Map Shows Where 220mph Trains Would Go in the U.S.

#40

Post by derleth »

david_shaw wrote: post #2

I think that now, perhaps more than ever, America and Americans would benefit from domestic high-speed rail. As someone who travels occasionally--albeit somewhat infrequently--for both business and pleasure, I share the opinion that flying is not altogether pleasant. From arriving at the airport several hours early, to dealing with TSA, to sitting in the cramped aircraft seating, it's not a stretch to say that it's a…

> the journey itself is pleasant while watching the world pass by outside

Unless high-speed rail becomes successful enough to become a real option, in which case they'll be economically forced to pack customers in like the economy class on modern airliners, if not tighter, to maximize revenue.

> as a project that would likely be subsidized with tax dollars

... it's going to have to wait for enough of the Tea Party to die off before it's politically viable, and by 'Tea Party' I mean anyone who is primarily concerned whether every single cent the government spends can be justified through a purely Originalist reading of the Constitution unless the money is going to fund the military and/or the police.

Post reply on HN