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Elon Musk Claims U.S. Approval for World’s Longest Tunnel (hyperloop stuff)

johnny956

Member
It was 202mph - which for an electric train is kind of run of the mill?
I thought the point of a hyper loop was the vacuum, and suspended in way to minimise any movement. Otherwise it's just an electric car running on a straight track.

I see the tech breakthrough of a hyperloop idea (vacuum) but what I don't see is a team break through in trials that proves anything in this competition update.

It was a team of 30 German students. That same team reached a speed of 58 mph in January. I would say it's progressing decently
 

mrklaw

MrArseFace
What happens when the Hyperloop pod needs to make an emergency stop, e.g. in the event of an earthquake?

Couldn't the deceleration really fuck you up?

No because they’d set the emergency deceleration at a level that humans can cope with. Like with existing high speed trains. They’d just have a longer stopping distance due to higher speed.
 
No because they’d set the emergency deceleration at a level that humans can cope with. Like with existing high speed trains. They’d just have a longer stopping distance due to higher speed.

But what if the earthquake causes a blockage in the tube (or complete collapse) within the safe stopping distance to the pod travelling at 700mph?

Yeah, ok, I'm being a little wild with the hypotheticals now, but I'm genuinely interested in how they'll engineer in safety features for this.

My biggest concern, tbh, is the vacuum in the tube... I mean, what if one of the cars leak? Will passengers have their own independent—limited—air supply?
 
But what if the earthquake causes a blockage in the tube (or complete collapse) within the safe stopping distance to the pod travelling at 700mph?

Yeah, ok, I'm being a little wild with the hypotheticals now, but I'm genuinely interested in how they'll engineer in safety features for this.

...people would die?

Maybe someone will come up with a better answer, but as morbid as it sounds, this is just so much less likely than a standard car crash it doesn't seem like a major concern to me. Not to say that we shouldn't ensure safety as much as possible, but if this takes even a small number of cars off the streets—as I assume it would—it will have already improved overall safety even with the possibility of freak accidents.
 

TarNaru33

Banned
But what if the earthquake causes a blockage in the tube (or complete collapse) within the safe stopping distance to the pod travelling at 700mph?

Yeah, ok, I'm being a little wild with the hypotheticals now, but I'm genuinely interested in how they'll engineer in safety features for this.

My biggest concern, tbh, is the vacuum in the tube... I mean, what if one of the cars leak? Will passengers have their own independent—limited—air supply?


I do not think the goal is a complete vacuum, just near vacuum. I am not sure if we have the tech to slow down the pod inside the tube enough to not cause fatalities if such a thing were to happen. Even if so, it would be like an airplane crashing into the ground. We run the risk of airplane crashes all the time and accidents do occur in which passengers have a lower chance to survive, but it is still safer to fly than to drive.

That is quite interesting what you said I am sure it would have to have some type of backup or recycling the oxygen inside of the pod.
 
Problem is, if you don't go near complete vacuum then you might as well just build a maglev. Far cheaper. If you do go near complete vacuum then there are all sorts of problems with the concept that basically means this'll never happen.

Watch Thunderfoot's videos on the subject. The guy is a massive asshole, but he explains well why it's not going to happen... at least in its "ideal" form.

https://www.youtube.com/user/Thunderf00t/search?query=hyperloop
 
...people would die?

Maybe someone will come up with a better answer, but as morbid as it sounds, this is just so much less likely than a standard car crash it doesn't seem like a major concern to me. Not to say that we shouldn't ensure safety as much as possible, but if this takes even a small number of cars off the streets—as I assume it would—it will have already improved overall safety even with the possibility of freak accidents.

That, and the fact that there aren't that many methods of transport that are unaffected by earthquakes if they're in the wrong place at the wrong time. Aircraft and Submarines are about it.
 
That, and the fact that there aren't that many methods of transport that are unaffected by earthquakes if they're in the wrong place at the wrong time. Aircraft and Submarines are about it.
Nah, submarines can be affected by earthquakes. Wouldn't want to be anywhere near the ocean floor during one, or in the path of a Tsunami.
 
Problem is, if you don't go near complete vacuum then you might as well just build a maglev. Far cheaper. If you do go near complete vacuum then there are all sorts of problems with the concept that basically means this'll never happen.

Watch Thunderfoot's videos on the subject. The guy is a massive asshole, but he explains well why it's not going to happen... at least in its "ideal" form.

https://www.youtube.com/user/Thunderf00t/search?query=hyperloop

I'll check it tonight, I'm at work right now... However, the first impression I have from watching this is that the guy is just a moron

n03QAky.png


I mean, wtf are these titles and thumbnails? Lol
 

TarNaru33

Banned
I'll check it tonight, I'm at work right now... However, the first impression I have from watching this is that the guy is just a moron

n03QAky.png


I mean, wtf are these titles and thumbnails? Lol

I watched some of his videos already, he feels more like a naysayer as if kinks cant be worked out later on as testing develops.
 
Nah, submarines can be affected by earthquakes. Wouldn't want to be anywhere near the ocean floor during one, or in the path of a Tsunami.

Well no, I wouldn't want to be, but they typically fare much better than surface ships in the resulting tsunami as long as, like you say, they aren't right near the bottom.
 
I do not think the goal is a complete vacuum, just near vacuum. I am not sure if we have the tech to slow down the pod inside the tube enough to not cause fatalities if such a thing were to happen. Even if so, it would be like an airplane crashing into the ground. We run the risk of airplane crashes all the time and accidents do occur in which passengers have a lower chance to survive, but it is still safer to fly than to drive.

That is quite interesting what you said I am sure it would have to have some type of backup or recycling the oxygen inside of the pod.

Even if it's a partial vacuum—which it obviously will be as the engineering challenges of creating a full vacuum in a 220 km 6ft(?) diameter tube would be near insurmountable—lowering the barometric pressure within the tube from 1 atm will lower the partial pressure of oxygen in the tube.

Air normally has around 21% Oxygen. Humans need a minimum of 19.5% O2 at 1 atm (= 101.3 kPa) in order to survive.

So that's a partial pressure of 19.75 kPa of Oxygen.

If they lower the air pressure within the Hyperloop, they can only lower it to a pressure of roughly 0.93 atm before they drop below the atmosphere inside the tube being considered breathable.

A 7% drop in pressure isn't going to do much in the way of lowered air resistance in the tube. So it's clear that the tube isn't going to have a breathable atmosphere.

In which case, I foresee a metric crap tonne of engineering challenges, e.g.:
  • How do we make sure that each passenger pod is leak tight?
  • If we make the pods leak-tight, then with such small air volumes within, how do we ensure that in case of an emergency situation, the pods have sufficient breathable air to allow enough time for the people in a stuck pod in the tube to be rescued?
  • How will they do any maintenance on the tube interior with the tube interior under a non-breathable vacuum?
  • Will there be facilities to rapidly flood the tube with a breathable atmosphere? If so how quickly can you actually flood a 220km/6ft diameter tube (i.e. ~580,000 m³)?
The list goes on...
 

darscot

Member
Even if it's a partial vacuum—which it obviously will be as the engineering challenges of creating a full vacuum in a 220 km 6ft(?) diameter tube would be near insurmountable—lowering the barometric pressure within the tube from 1 atm will lower the partial pressure of oxygen in the tube.

Air normally has around 21% Oxygen. Humans need a minimum of 19.5% O2 at 1 atm (= 101.3 kPa) in order to survive.

So that's a partial pressure of 19.75 kPa of Oxygen.

If they lower the air pressure within the Hyperloop, they can only lower it to a pressure of roughly 0.93 atm before they drop below the atmosphere inside the tube being considered breathable.

A 7% drop in pressure isn't going to do much in the way of lowered air resistance in the tube. So it's clear that the tube isn't going to have a breathable atmosphere.

In which case, I foresee a metric crap tonne of engineering challenges, e.g.:
  • How do we make sure that each passenger pod is leak tight?
  • If we make the pods leak-tight, then with such small air volumes within, how do we ensure that in case of an emergency situation, the pods have sufficient breathable air to allow enough time for the people in a stuck pod in the tube to be rescued?
  • How will they do any maintenance on the tube interior with the tube interior under a non-breathable vacuum?
  • Will there be facilities to rapidly flood the tube with a breathable atmosphere? If so how quickly can you actually flood a 220km/6ft diameter tube (i.e. ~580,000 m³)?
The list goes on...


You do realize planes have all of these issues, all your points are trivial.
 
You do realize planes have all of these issues, all your points are trivial.

Planes fly in 220 km long vacuum tubes underground?!? Planes are single passenger vessels?...

errr... what?!?

No, planes don't have any of the issues I mentioned above. They fly in the skies and the skies don't need to be maintained. The air pressure at a planes' cruising altitude is higher than pressure in these tubes. Planes can't get stuck in the air, needing their crew and passengers to be rescued from an environment that lacks a breathable atmosphere.

If you think that planes are "essentially" the same thing... then I don't even...
 
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