I think he meant 1G at maximum acceleration. Obviously at maximum speed there would be zero forward acceleration.

Always wanted to be a bullet.

What could go wrong?

>> ^budzos:

What could go wrong?

Oil Company's Wallets

WHY ARENT THEY BUILDING THIS NOW!?!?!

refer to the 1976 book "A world out of time" By Larry Niven

Think you could just tell us? I, for one, am not going to go find and read a book based on a vague comment on the Sift.>> ^deathcow:

refer to the 1976 book "A world out of time" By Larry Niven

>> ^messenger:

Think you could just tell us? I, for one, am not going to go find and read a book based on a vague comment on the Sift.>> ^deathcow:
refer to the 1976 book "A world out of time" By Larry Niven



they use this exact system

Sweet. I heard about this idea maybe ten years ago. Whoever it was said that we already had all the technology to do it, it's just that it was prohibitively expensive at the time. I guess that time's passed now, if this video is to be believed.

AT this point I have to think that any truly good idea's (like this one) are really being held back for the most part due to oil or other companies that stand to take massive profit losses interfering with them legally. It stands to reason that if a technology threatens their bottom line significantly enough it would warrant the expenditure of resources to halt or delay the deployment of said tech for as long as possible. It's a bit conspiratorial but it also makes perfect sense from a financial pov on the part of the Co.>> ^PalmliX:

WHY ARENT THEY BUILDING THIS NOW!?!?!

>> ^RadHazG:

AT this point I have to think that any truly good idea's (like this one) are really being held back for the most part due to oil or other companies that stand to take massive profit losses interfering with them legally. It stands to reason that if a technology threatens their bottom line significantly enough it would warrant the expenditure of resources to halt or delay the deployment of said tech for as long as possible. It's a bit conspiratorial but it also makes perfect sense from a financial pov on the part of the Co.>> ^PalmliX:
WHY ARENT THEY BUILDING THIS NOW!?!?!



I sadly have to agree with your statement...

On the other hand, science is more international now. China will probably be the first to build it.

Update: "Researchers at Southwest Jiaotong University in China are developing (in 2010) a vactrain to reach speeds of 1,000 km/h (620 mph). They say the technology can be put into operation in 10 years." en.wikipedia.org/wiki/Vactrain


>> ^RadHazG:

AT this point I have to think that any truly good idea's (like this one) are really being held back for the most part due to oil or other companies that stand to take massive profit losses interfering with them legally. It stands to reason that if a technology threatens their bottom line significantly enough it would warrant the expenditure of resources to halt or delay the deployment of said tech for as long as possible. It's a bit conspiratorial but it also makes perfect sense from a financial pov on the part of the Co.>> ^PalmliX:
WHY ARENT THEY BUILDING THIS NOW!?!?!

what happens when the oxygen in your pod runs out over Kansas seeing your in a vacuum tube?

Naturally its a large pod. Plenty of room for compressed slow release breathable air tanks. We send air with men on spacewalks, we can surely keep a large capsule with 6 people filled for a while.
>> ^saber2x:

what happens when the oxygen in your pod runs out over Kansas seeing your in a vacuum tube?

Big business is naturally conspiratorial, so that's certainly no strike against your theory. Seems reasonable. or it just may be that not enough people know about it yet and they simply lack the venture capital.>> ^RadHazG:

AT this point I have to think that any truly good idea's (like this one) are really being held back for the most part due to oil or other companies that stand to take massive profit losses interfering with them legally. It stands to reason that if a technology threatens their bottom line significantly enough it would warrant the expenditure of resources to halt or delay the deployment of said tech for as long as possible. It's a bit conspiratorial but it also makes perfect sense from a financial pov on the part of the Co.>> ^PalmliX:
WHY ARENT THEY BUILDING THIS NOW!?!?!

I know we can do it, but it wont be NASA prepping your pod, it will be some jackass that use to work at McDonalds. All im asking is what do they do if you do have a emergency or mechanical failure?

>> ^RadHazG:

Naturally its a large pod. Plenty of room for compressed slow release breathable air tanks. We send air with men on spacewalks, we can surely keep a large capsule with 6 people filled for a while.
>> ^saber2x:
what happens when the oxygen in your pod runs out over Kansas seeing your in a vacuum tube?

Fair enough. I can imagine a number of safety/emergency protocols but I've no idea how cost effective they would be. Given the simplicity of the system I can't imagine it would be to difficult though. Hell we send people through the sky in an aluminum tube over 10,000 feet in the air all the time, I can't imagine this would be any more dangerous. The first several years will undoubtedly have some accidents, every new tech does. If we never tried new things though we'd never go anywhere.
>> ^saber2x:

I know we can do it, but it wont be NASA prepping your pod, it will be some jackass that use to work at McDonalds. All im asking is what do they do if you do have a emergency or mechanical failure?
>> ^RadHazG:
Naturally its a large pod. Plenty of room for compressed slow release breathable air tanks. We send air with men on spacewalks, we can surely keep a large capsule with 6 people filled for a while.
>> ^saber2x:
what happens when the oxygen in your pod runs out over Kansas seeing your in a vacuum tube?

OK... Just the physics of this is slightly stupid on the face of it.

So. Take a plastic straw. Put another straw on it. And another. Do this until you have a straw that is 4 feet long. Now try to drink a milk shake. The resistance of a tube is proportional to its length. So to make this work you would need to have numerous relay stations to charge up the vacuum. And they would have to be enormous mechanical pumps, which would be a nightmare to service and operate.

*promote

Promoting this video back to the front page; last published Wednesday, April 18th, 2012 10:10pm PDT - promote requested by MycroftHomlz.

as said in the video, the cars don't move by sucking it through a straw, but by magnetic levitation
they draw the air out of the tubes and use magnets to speed it up, which is very efficient due to lack of air friction
there's a ton of problems with this though
it would need to be (relatively) airtight and stable throughout
that can't be too cheap, whatever the material
constant maintenance
what if there was an external accident that dents the tube, like a failing support structure, and the train-car later comes to that dent at this huge speed?
it would be worse than a plane coming apart midair

great for scifi, but i don't see it being reality any time soon

Why couldn't it be cheap to maintain a vacuum? It doesn't have to be anywhere near a total vacuum (which is mechanically impossible, BTW), just a relative vacuum. Any reduction in air density results in decreased air resistance, and increased top speed. I don't know the physics of it, but I'm guessing that even a 50% air density vacuum would result in a massive top speed increase. In a perfect vacuum, the theoretical top speed would be (acceleration force) x (track length). This 6,500 km/h number may be a limit imposed only by how good a vacuum they think can be reliably produced.

And about safety, obviously the track wouldn't be built in a bare tube that could dent or break. The tube could be whatever material, but then encased in something else and/or buried so nothing could fall on it/crash into it/etc. Before it went into operation, for consumer confidence (and even before production, for investor confidence) it would have to be demonstrated that the structure is strong enough to withstand any reasonably foreseeable event. I'd be mostly worried about earthquakes, personally, especially when crossing the Pacific.

Just like with aviation and normal trains, it will have its growing pains and regular disasters, but I bet it ends up being on par safety-wise with flight, and significantly cheaper, given the fuel savings.>> ^shole:

as said in the video, the cars don't move by sucking it through a straw, but by magnetic levitation
they draw the air out of the tubes and use magnets to speed it up, which is very efficient due to lack of air friction
there's a ton of problems with this though
it would need to be (relatively) airtight and stable throughout
that can't be too cheap, whatever the material
constant maintenance
what if there was an external accident that dents the tube, like a failing support structure, and the train-car later comes to that dent at this huge speed?
it would be worse than a plane coming apart midair
great for scifi, but i don't see it being reality any time soon

Did some Wiki-ing, and found that even the vacuum in Thermos bottles have fewer air particles by a factor ranging form 100,000 to 10,000,000.

http://en.wikipedia.org/wiki/Vacuum#Examples

You're Wrong Charlie, you get no lifetime supply of chocolate. They actually only said in the video magnets make it go up. They did not say it was a maglev train. These are entirely different animals. It is called evacuated tube because of a vacuum. Thanks for the physics lesson though.

>> ^shole:

as said in the video, the cars don't move by sucking it through a straw, but by magnetic levitation....

Another pipe dream.

>> ^deathcow:

refer to the 1976 book "A world out of time" By Larry Niven


Wow that looks awesome. I'm gonna get a copy.

>> ^MycroftHomlz:

You're Wrong Charlie, you get no lifetime supply of chocolate. They actually only said in the video magnets make it go up. They did not say it was a maglev train. These are entirely different animals. It is called evacuated tube because of a vacuum. Thanks for the physics lesson though.
>> ^shole:
as said in the video, the cars don't move by sucking it through a straw, but by magnetic levitation....



The tube contains a vacuum, meaning there's no air to push or pull you forward. It must use maglev propulsion as well. The lack of air allows you to go 6500km/h without burning up or causing sonic booms.

>> ^budzos:

>> ^deathcow:
refer to the 1976 book "A world out of time" By Larry Niven

Wow that looks awesome. I'm gonna get a copy.


Go to book store (or amazon, kindle or otherwise),
follow aisles until "Larry Niven" section found,
purchase a copy of everything found there,
win.

You might do at least minimal research before calling someone wrong:

"A vatrain is a maglev train run through an evacuated tunnel." -- The Whole Internet>> ^MycroftHomlz:

You're Wrong Charlie, you get no lifetime supply of chocolate. They actually only said in the video magnets make it go up. They did not say it was a maglev train. These are entirely different animals. It is called evacuated tube because of a vacuum. Thanks for the physics lesson though.
>> ^shole:
as said in the video, the cars don't move by sucking it through a straw, but by magnetic levitation....

The second decree: no more pollution, no more car exhaust,
Or ocean dumpage. From now on, we will travel in tubes!

the future: a series of tubes.

The US can't even pony up the money for the kind of high speed rail that Europe has had for 30 years. I see China beating us to this one by about a century.

Concession.

>> ^RadHazG:

Naturally its a large pod. Plenty of room for compressed slow release breathable air tanks. We send air with men on spacewalks, we can surely keep a large capsule with 6 people filled for a while.
>> ^saber2x:
what happens when the oxygen in your pod runs out over Kansas seeing your in a vacuum tube?



And they kind of need air in the vehicle too..... like, a lot of it? Never mind the spacewalks. As in, that's of no concern.

For the record I still think this is stupid.