
Hyperloop One Becomes ‘Virgin Hyperloop One’ - mpweiher
https://techcrunch.com/2017/10/12/hyperloop-one-becomes-virgin-hyperloop-one-with-virgin-group-investment/
======
Animats
Maglev in a tube is a proven technology at full train scale. Here's the Chuo
Maglev from the inside.[1] 500KPH in tunnels. They're not pumping down the
tunnels, just plowing through on sheer power and money.

The Chuo Maglev makes the Hyperloop One look like a toy project. Watch the
video. They have a production-quality train, with tourists and whiny kids
riding it, going 500km/h. They've hit 603km/h in tests, but don't run it that
hard normally. This is the first section of track between Tokyo and Osaka via
Nagoya. Planned opening to Nagoya is 2027. Japan's Alps are in the way.
They're tunneling straight through. Longest tunnel segment is 25km and it's
being drilled now. 90% of the Tokyo-Nagoya segment will be in tunnel. Stations
in Tokyo and Nagoya are under construction. The line will probably run 3-4
trains an hour each way, like the existing Shinkansen.

Hyperloop potentially has a higher speed to 900-1200km/h, but that may not be
achieved in practice. The Chuo Shinkansen has a turn radius of 8km, and
passengers don't have to be strapped in. Hyperloop would need 4x the radius to
go twice as fast with the same ride quality. Laying out a route with a 24km
turn radius severely limits where track can go.

Strapping everybody in and pulling 0.5G sustained is not going to go over with
customers. Commercial aircraft usually stay within +-0.25G. Maybe 0.5G in mild
turbulence, and customers don't like it.

[1]
[https://www.youtube.com/watch?v=HZ6dYhHIol8](https://www.youtube.com/watch?v=HZ6dYhHIol8)

~~~
bertil
I’d separate:

\- longitudinal, predictable acceleration, where you can safely tell people to
stay in their seats and all will be fine, I’m quite confident most humans
would be comfortable with 1G horizontal that adds up to 1.5G diagonal: that’s
basically a roller-coaster; it’s not too bad if you ease people into it, i.e.
you minimise the jerk;

\- lateral, predictable acceleration, like one would expect in turns: not
familiar with train technology enough to know if you could adapt pendular
train to MagLev, but it seems like a simple enough hack to increase comfort
significantly;

\- vibrations and turbulences: seem unlikely in a tube on rails, without a
train coming in the opposite direction. Those definitely, customers don’t
like.

~~~
ZoFreX
Lateral acceleration is much more annoying to deal with than longitudinal or
vertical, even if it's constant. Perhaps they could tilt in bends to convert
some of that lateral to vertical?

~~~
athenot
Yes, and with no windows, there's zero correlation between acceleration and
visual cues. That's a perfect recipe for motion sickness.

~~~
delinka
Our local trains have cars that can lean a bit on their own. Bank the track a
bit, lean the car as needed, the humans on board don't recognize a turn unless
they're watching intently out the window.

------
Robotbeat
The biggest problem people have with Hyperloop is because it certainly seems
like Elon Musk just waltzed into the high speed rail debate and Dunning-
Krugered some crazy scheme that doesn't look anything at all like conventional
approaches to the problem and thus doesn't jive with any common sense we might
have built up around different transport methods.

But that's kind of what Elon Musk does: he Dunning-Krugers himself into a new
industry every couple of years, using a simplified, undergraduate physics
level of analysis to find something that (to an optimistic non-field-expert)
looks like a better solution to the problem.

And the most annoying thing of all is that he usually _succeeds_. Often in
spite of his original idea being technically wrong. For instance, Falcon 9 was
supposed to be recovered with parachutes... that didn't work, and people who
were working on vertical landing rockets told them that, but at the time Elon
just rolled his eyes and said "just use parachutes." But SpaceX/Elon found out
the idea didn't work and switched to the "correct" solution and got it to work
operationally (and with paying customers) much faster than people who had been
working on the problem for years before.

The moral of the story is that it's often better to be able to execute fast
even if you start out wrong than to take your time with the right answer.

~~~
Hypx
This is also a good time to introduce the concept of survivorship bias.
There's a fair chance that it was mostly luck, not ability, that it ultimately
succeeded.

~~~
rocqua
I used to think that about Musk, but his successes seem to be piling up.
Specifically: Paypal, Tesla, and Space-X all seem to be rather successful.

~~~
nolok
SolarCity failed (and he had to buy it back himself with Tesla), Paypal was a
success but it wasn't his, his part was x.com which was kind of a failure on
its goal and had to sell (just because it sold for a lot of money doesn't mean
it succeeded, in the terms of "success" we're discussing in this thread).

Tesla has yet to make any money and fails to meet its deadline, and it's yet
to see how it will far now that the car giants are turning to EV (especially
with many countries setting deadline in 2016 and 2017 about the end of non EV
cars, which jolted all the big ones into joining).

Space-X is for me his one real success so far, it leaned on a lot of public
funding to do it so it's really not the kind of things usual for HN, but they
said they would re-use when everyone else said "can't be done" or "not worth
it", and they're getting there.

------
biznickman
The viability of Hyperloop One should not be the focus in the context of this
article. That's not what this is about at all.

It's that Hyperloop One needed Richard Branson on board because Elon Musk is
creating his own competitor now. This is an incredibly smart move to ensure
the survivability of the business from a publicity perspective.

Branson has a history of doing things that people thought impossible or just a
bad decision (like creating an airline company). Public perception is the name
of the game at this stage, not just feasibility. From that perspective,
Hyperloop One has effectively done one of the only strategic moves remaining
at this point that ensures it has any chance of persuading a government to
select them as a preferred vendor (or continue doing so).

~~~
detritus
Branson's missing a d from his almost nominatively-determining name — the
guy's got a talent for self publicity over challenging the incumbency, which
for the most part he hasn't since launching Virgin Airlines and Megastores,
which were both back in the 80s.

~~~
detritus
Downvotes? Presumably not from Britons or anyone who knows anything about the
guys history?

So what HAS he done then, other than brand anything he can then offload to
third and fourth parties to run the businesses for him?

And don't say Virgin Galactic - that's just some clever peripheral branding to
encourage the likes of the downvoters here that he is in any way novel or
dynamic.

He's marketing clever, not strategically or developmentally-so.

~~~
adventured
He's worth $5 billion. He's a high-school drop-out dyslexic that started from
nothing. He built a successful airline and record label, along with countless
successful branded companies whose success partially rides on the vast effort
he has put into building his own well-known brand - a substantial feat unto
itself.

Yes, golly gee, what HAS he done.

~~~
detritus
I trust my respone to 'waegawegawe' pads out where I'm coming from.

He has a certain reputation here in Britain, however we here in Britain also
have a certain reputation of shitting on people's success - I sincerely hope
that's not how I'm coming across here.

Anyway, this is tangential nonsense, I'm sorry for diluting discourse!

~~~
kbenson
> however we here in Britain also have a certain reputation of shitting on
> people's success

That's okay, I appreciate you loaning us John Oliver. ;)

~~~
detritus
In a sense, I think you gave him to us. You often do :)

------
kumarski
Something I wrote a while ago.... w/ back of the napkin calculations.......

Why I wouldn’t invest a money into Hyperloop

\- Stabilizing a single fault line risk pylon is more than $250K.

\- How many million are needed for vacuum pumps to evacuate 100+ million cubic
feet of of pipe to 100 Pa?

\- Hot air discharge needs to go somewhere. For every 1 bar pressure, you need
~200 to ~400 cubic meters of volume which is larger

\- This seems very much like one of those Andy Grove Fallacies.

\- The hyperloop is a mega engineering project on the ground. Nobody on their
team is a civil engineer. Looking at their team objectively, there seems to be
a mismatch of competency.

\- At its core, the science i good, the cost-economics do not work. Das ist
nicht gute.

~~~
Analemma_
When Musk first said that an LA<->SF Hyperloop could be built for 1/8th the
cost of the equivalent HSR, I chuckled and then waited for the punchline,
which still hasn’t arrived.

It’s a cool idea and I do want to see more prototypes and feasibility studies,
but people need to get off the hype train (no pun intended) and be realistic
about the cost.

~~~
hbosch
Okay, we'll bookmark this for the future. Amtrak estimated a HSR/"bullet
train" from D.C. to Boston would cost ~$151 billion. Since LA to SF will only
be two stops, and we can assume Amtrak estimated at least 4 (Philly and NYC)
let's bring the number down closer to $100 billion to make it even.

Do we think the Hyperloop costs are more or less than that? 1/8 of a
theoretical $100b is $12.5b -- is $12.5billion for Hyperloop unreasonable? I
have no opinion on cost personally, and I don't know economics, but this $151
billion from D.C. to Boston was floated by the established US player in rail
infrastructure. Anything less than that number is fantastic, right?

~~~
dx034
You cannot compare D.C to Boston with SF to LAX. The east coast has much
denser population so that you need more tunnels. LAX to SF HSR would not cost
$151bn. Start and end are expensive but the part in the middle is "relatively"
cheap.

~~~
hbosch
Right, for comparison's sake I chopped off $51 billion bucks from the
Northeast Corridor projection in the interest of balancing out the two.

Just because I felt like doing some more Google-fu, I found an article in the
LA Times[0] that says a California HSR/bullet-train project is going to
overshoot it's original budget (and deadline) of $68 billion. There's a lot of
info out there about this project, and it's potential overruns, but let's
forget all that and just stick to the original planned cost: $68 billion, so,
about _half_ of the cost of Amtrak's northeastern bullet. Let's use that
number for our comparison.

If we are going to hold Elon to his "we can do it for 1/8th the cost" blurb,
then we are giving him like $8.5 billion to use for his SF/LA Hyperloop.
Still, that doesn't sound unreasonable, right? He'll get a good deal on tunnel
boring with his other company, and fuselage manufacturing can be handled by
SpaceX. When it comes to financing, I don't think it's a major issue compared
to other infrastructure works out there.

Like I said, though, I'm just going off the top of my head. I don't know
finance or economics or vacuums or magnets.

There's a new LIRR train being dug in NYC called East Side Access. This is a
commuter rail line, and is going to cost ~$10 billion or so[1]. Logistically
these aren't the same, obviously, but if adding to the LIRR is worth ~$10b
then surely the Hyperloop experiment is as well, right?

EDIT: Also, just for disclosure, I don't live in California and I'd probably
never end up using the Hyperloop myself so I'm neither for nor against it
versus any HSR. I just want to entertain the idea that cost shouldn't be the
main focus of discussion IMO.

___

0\. [http://www.latimes.com/local/california/la-me-bullet-
train-c...](http://www.latimes.com/local/california/la-me-bullet-train-cost-
final-20151025-story.html) 1\.
[http://web.mta.info/capital/esa_alt.html](http://web.mta.info/capital/esa_alt.html)

~~~
rohit2412
> If we are going to hold Elon to his "we can do it for 1/8th the cost" blurb,
> then we are giving him like $8.5 billion to use for his SF/LA Hyperloop.
> Still, that doesn't sound unreasonable, right

I think boring company claimed it can bring down costs to 100 million dollars
per mile (how? Just reduce tunnel size! SMH. Plus 100 million dollar a mile
isn't too far from prices of current tunnels). Sf to la is 380 miles. That's
38 billion dollars just for the tunnel?

I think hyperloop is certainly feasible, if you spend hundreds of billions in
it, the problems can be dealt with costly engineering.

If you think hsr will cost 150 billion, a maglev will be costlier, tunnels are
extremely costly to build, but building a maglev in a vacuum tunnel will cost
only 6 billion? How will cost savings of an order of magnitude happen?

------
lisper
All of the Hyperloop development efforts are ignoring the elephant in the
room: thermal expansion. If you do the math, the ends of a viable hyperloop
track will have to move _hundreds of meters_ [1]. No one has yet advanced even
a viable _idea_ for how to deal with that, let alone an actual design. Until
that happens, the Hyperloop is vaporware.

[1] It's a trivial calculation. The thermal expansion coefficient of steel is
about 10^-5. A typical run of, say, SF->LA is 600 km. Temperatures in the
central valley range over about 100 degrees. Multiply everything together and
the result is 600 meters.

~~~
pasta
Yeah, Elon Musk never thought about that because he was busy landing rockets.

Come on.. why do you think he did not think about that?

By the way, curves in the track can eliminate this when they can slide a
little. And I can imagine there are more and better solutions.

~~~
oconnor663
Relevant: [http://www.commitstrip.com/en/2016/06/02/thank-god-for-
comme...](http://www.commitstrip.com/en/2016/06/02/thank-god-for-commenters/)

------
sschueller
When are we going to address the elephants in the room?

Just the tube alone:

    
    
      - largest pressure vessel in the world. How do you keep it at near vacuum?
      - Thermal expansion over such a large distance, especially if the top of the tube is warmer than the bottom.
      - Safety, how does an evacuation look like if the tubes are sealed?.
    

There are many more. Some how I feel like this is a "pipe" dream. Lots of
marketing, very little engineering.

~~~
Faaak
The CERN LHC tube is a 27km circle of vacuum and near-zero temperature, and
they don't seem to have a problem with that (granted, they had some but it's
solved now).

Frankly, yes, there may be issues, but I'm confident that the Human race will
be able to overcome those.

~~~
ginko
The LHC's vacuum pipes are 6.3 cm in diameter..

~~~
iamgopal
What, really? What's with all those mega photos we see everywhere ?

~~~
delecti
This picture shows a cross section of part of the LHC. Those two yellow lines
sticking out are the actual tubes. Everything else is equipment to manage the
particles (detectors, containment, magnetic propulsion).

And for a sense of scale, a human can comfortably stand in that tunnel next to
it.

Image:
[http://www.tut.fi/cs/groups/public_news/@l102/@news/@p/docum...](http://www.tut.fi/cs/groups/public_news/@l102/@news/@p/documents/kuva/x194225.jpg)
From here: [http://www.tut.fi/en/about-tut/news-and-events/tut-and-
cern-...](http://www.tut.fi/en/about-tut/news-and-events/tut-and-cern-
collaborate-in-development-of-particle-accelerators-of-the-future-x194226c2)

------
daemin
Just as a thought experiment, could the promotion of these "hyperloop"
projects be a clever political ploy to misdirect/divert attention and prevent
a viable high speed rail network from being built?

Elon's main business is electric cars and (one of) Branson's is airlines. So a
reasonable competitor to both is fast and cheap(er) public transport along a
major travel corridor in the USA.

This means that by promoting this alternative to high speed rail as faster,
cheaper, better, they are undermining public support for a real project, which
could mean its end.

~~~
jaredhansen
Of all the problems facing construction of "viable high speed rail" in the US
(they already exist in many other places), I don't think Hyperloop competition
is among ... the top 50.

Practically anything _could_ be "a clever political ploy", but where's the
evidence for this? Any in the absence of such evidence, why speculate?

 _Just as a thought experiment, could HN user daemin 's comments be part of a
clever ploy to invent a fake persona to distract from a SECRET AGENDA?_ ;)

~~~
Brakenshire
We're just building a new major high speed line in the UK, and you'd be
surprised how often you hear people say that it shouldn't be built because the
technology will be superseded by the hyperloop, or autonomous cars, or
whichever. It's one of the major talking points, even if it isn't one of the
major blocks.

~~~
mseebach
Meh. The imminency of "Major New Technology Just Around The Corner" has always
been a favourite argument for the anti-progress crowd.

EDIT to add: Before Hyperloop, it was Maglev.

And frankly, a significantly better argument against HS2 is that it's an
impossibly expensive boondoggle.

~~~
Brakenshire
> a significantly better argument against HS2 is that it's an impossibly
> expensive boondoggle.

Nah, it connects most of England's largest cities, and will be 2/3rds of the
network which will connect all of the cities of the North of England into
something approaching a single labour market. Liverpool, Leeds, Sheffield,
Manchester, Birmingham will be all be within 30-50 minutes of each other, with
London within an hour and a half, with trains running between destinations 2
or 3 times an hour. The value of that is enormous.

~~~
gaius
It would have been politically a LOT easier of they'd built a Birmingham-
Newcastle leg first

~~~
sgt101
and probably better for the long term economy as well; the last thing
Birmingham needs is a reason why London is a good base for doing business in
Birmingham.

~~~
vidarh
This is a pet peeve of mine. It hurts not just the other cities in the UK, but
London as well. We don't alleviate overcrowding in London by making it easier
to move to London. We alleviate overcrowding in London by making more other
locations economically stronger.

That should mean strengthening a region around Birmingham, faster links
connecting the Leeds - Sheffield - Manchester triangle + tack on Liverpool,
and a wide orbital _around_ London improving connections between the towns
around London that now are reduced to feeder/sleeper towns. There are towns
around London that _has_ decent direct rail tracks, but where the fastest rail
route is a 2x-3x longer journey in to a London terminal and back out again.
Actually run direct trains, and you suddenly have new viable commuter regions
that bypass the centre.

Only _after_ that should we think about making the links between these centres
faster.

The problem of course is that many of these will need to be run at substantial
losses for years before enough companies etc. will move/get established to
change transport patterns, and it's so much easier to justify building more
expensive routes where there is existing overcrowding.

Never mind that doing so just attracts more people.

------
JumpCrisscross
The original Hyperloop paper quotes its design pressure as “about 1/6 the
pressure of the atmosphere on Mars” [1]. Martian atmospheric pressure is
“about 0.6% of Earth's mean sea level pressure” [2]. So 0.1% of Earth’s
surface pressure, or a 1,000:1 pressure change.

To put that in perspective, the Boeing 787’s GEnx-2B67, the most powerful GEnx
engine variant, generates a 43:1 pressure ratio [3]. To get a sense of the
engineering differences between 6:1 and 1,000:1, look at NASA’s Space Power
Facility [4].

The Hyperloop’s thermal issues are a hard enough problem that they alone put
this in the domain of materials science. That’s the same category of problems
separating us from a space elevator.

The Hyperloop always seemed like a transportation system not for this planet.
The thermal issues, too, become trivial to solve on Mars: bury the tube. Mars
does not appear to be too seismically active [5] and has no existing property
rights to take into account [ _citation needed_ ]. (The lack of water also
makes steel more viable.)

[1]
[http://www.spacex.com/sites/spacex/files/hyperloop_alpha-201...](http://www.spacex.com/sites/spacex/files/hyperloop_alpha-20130812.pdf)

[2]
[https://en.m.wikipedia.org/wiki/Atmosphere_of_Mars](https://en.m.wikipedia.org/wiki/Atmosphere_of_Mars)

[3]
[https://en.m.wikipedia.org/wiki/General_Electric_GEnx](https://en.m.wikipedia.org/wiki/General_Electric_GEnx)

[4]
[https://en.m.wikipedia.org/wiki/Space_Power_Facility](https://en.m.wikipedia.org/wiki/Space_Power_Facility)

[5] [https://www.space.com/418-marsquakes-red-planet-
rumble.html](https://www.space.com/418-marsquakes-red-planet-rumble.html)

~~~
thearn4
Some colleagues of mine also did a short feasibility assessment of the
original white paper, and came to some similar conclusions. The propulsion
system also made some assumptions about compressor performance that seemed too
optimistic compared to existing turbomachinery.

That said, I have not followed closely enough to know if the hyperloop
startups out there are following the original conception or if it has
significantly evolved or not. I hear that they've ditched the compressor
altogether, but that's got to have a pretty big impact on expected speeds.

~~~
JumpCrisscross
> _Some colleagues of mine also did a short feasibility assessment of the
> original white paper, and came to some similar conclusions_

Likewise. It sounds like above-surface (on Earth) is probably unfeasible given
(a) security and (b) thermal concerns.

For security, we just contemplated debris from the track (or a bullet from an
errant rifle) puncturing the tube. Hyperloop One is testing an 3.3m diameter
and 500m long track [1]. That's 4,276 cubic meters [a]. "At sea level and at
15 °C air has a density of approximately 1.225 kg/m3" [2]. The air in the
Hyperloop One test track thus weighs about 5,200 kg.

If we use the Hyperloop's original design spec [3], a puncture means air on
one side at 1 atm expanding into the space on the other at 1/1,000 atm. This
simplifies to a wall of air moving at just below the speed of sound. Since the
speed of sound is about 330 m/s [4], the end of the tunnel will could hit with
a pulse with about 140 megajoules of energy [b]. That's the energy in about 30
kg of TNT [5][c].

> _I hear that they 've ditched the compressor altogether, but that's got to
> have a pretty big impact on expected speeds_

It currently sounds like a vactrain [1] with magnetic levitation [2].

[1] [https://arstechnica.com/cars/2017/03/hyperloop-one-shows-
pho...](https://arstechnica.com/cars/2017/03/hyperloop-one-shows-photos-of-
its-test-track-being-built-in-nevada/)

[a] pi * (3.3 / 2) ^ 2 * 500

[2]
[https://en.wikipedia.org/wiki/Density_of_air](https://en.wikipedia.org/wiki/Density_of_air)

[3]
[http://www.spacex.com/sites/spacex/files/hyperloop_alpha-201...](http://www.spacex.com/sites/spacex/files/hyperloop_alpha-20130812.pdf)

[4]
[https://en.wikipedia.org/wiki/Speed_of_sound](https://en.wikipedia.org/wiki/Speed_of_sound)

[b] (1/2) * (5200 / 2) * 330 ^ 2

[5]
[https://en.wikipedia.org/wiki/TNT_equivalent](https://en.wikipedia.org/wiki/TNT_equivalent)

[c] (140 * 10^6 / 4.184 * 10^9) * 10^3

[1]
[https://en.wikipedia.org/wiki/Vactrain](https://en.wikipedia.org/wiki/Vactrain)

[2]
[https://en.wikipedia.org/wiki/Maglev](https://en.wikipedia.org/wiki/Maglev)

~~~
schiffern
_sigh_ another "deadly wall of air" theory ala Thunderf00t? Hasn't this been
debunked already?

"A little bit of physics is a dangerous thing."

* A bullet or piece of debris would likely leave a hole much smaller than the diameter of the tube. A breach 1/10th the diameter of the tube will admit 1/100ths as much the air.

* Even if there _was_ a whole-tube breach, the "wall of air" will rapidly slow down and smear out into a gradual pressure rise due to friction with the tube walls. Pipes are not lossless! Within 5 km friction will have the air moving at highway speeds. So if you're so close that you can be killed by the air blast, you're so close that the pod can't brake before hitting the whole-tube breach (bad). In other words, "deadly pressure waves" don't increase your odds of dying beyond that of a regular "derailment" event.

* In the event of a breach (whole-tube or otherwise), sensors in the track will signal all the pods to stop and the tunnel to undergo emergency re-pressurization. So any "wave" won't get far.

~~~
JumpCrisscross
> _ala Thunderf00t_

Just watched one of his videos on this--interesting and thank you for the
pointer. Agree with you on his overstating the deadliness of pressure pulses.
30 kg of TNT is a lot of energy, certainly enough to knock your infrastructure
out of commission for a couple days. The "everyone dies if the tube is
punctured" argument is hyperbolic, though.

The materials science problem is the thermal expansion. And not the
longitudinal one that Thunderf00t mentions. It's the transverse expansion. If
these are above ground, the top will heat up relative to the bottom. That's a
nasty problem to solve while maintaining the structural integrity to keep a
giant vacuum with speeding capsules in place.

~~~
hwillis
> It's the transverse expansion. If these are above ground, the top will heat
> up relative to the bottom. That's a nasty problem to solve while maintaining
> the structural integrity to keep a giant vacuum with speeding capsules in
> place.

Right... you can probably solve that with a bucket of white paint. Worst case
you cover it with an aluminum shield- aluminum does not absorb infrared
radiation and will reflect 99.9% of ambient heat. Since the proposal included
covering large sections of the tube in solar panels that isn't even a
significant change.

~~~
JumpCrisscross
> _you can probably solve that with a bucket of white paint. Worst case you
> cover it with an aluminum shield- aluminum does not absorb infrared
> radiation and will reflect 99.9% of ambient heat_

It's, unfortunately, harder than this. It's a similar problem to the ones we
dealt with regarding rockets, standing fueled, on a pad. Both methods you
propose were tried. The solution is to (a) paint it and (b) launch before the
gradient becomes too big.

The stresses on the Hyperloop tube, when a capsule is rushing through it while
it's containing a near vacuum, are comparable to those on a rocket nearing max
Q [1]. The difference is with a rocket we take great care to maintain
symmetry. With the Hyperloop, that isn't an option. That persistent asymmetry
is what makes it a difficult materials problem, particularly if we're using
any known metals (even wonderful light and thermally-conductive aluminium).

[1] [https://en.wikipedia.org/wiki/Max_Q](https://en.wikipedia.org/wiki/Max_Q)

~~~
hwillis
Dude, what. That's bullshit, _and_ the size difference will be on the order of
dozens or low hundreds of microns. Not only that, but the distortion will be
spread evenly across the tube because it's a tube. You're just asserting that
putting the tube in shadow will somehow not block heat from the sun.

I'm also not sure you understand what I'm saying about an aluminum shield?
Aluminum has an emissivity coefficient of .04. Thermal conductivity has
nothing to do with it since it isn't touching the tube. It's purpose is just
to not re-radiate infrared onto the tube.

~~~
kbenson
I think what we have here is someone applying a known problem and solution
space for one industry (rocketry) to another (civil engineering). A large
vertical tube that needs to move quickly and under great stress may not allow
for the same solutions that apply to a large horizontal tube that is
relatively static.

Fixing a large enough solar shield above a rocket hundreds of feet in the air
which has to get out of the way quickly before the rocket launches has very
different requirements than fixing a shading structure above a vertical static
structure a few tens of feet in the air. I'm not sure how this problem was
solved in rocketry is necessarily indicative of how hard it is to solve in
other circumstances.

~~~
JumpCrisscross
> _I 'm not sure how this problem was solved in rocketry is necessarily
> indicative of how hard it is to solve in other circumstances_

Very fair. The advantage a rocket has is you choose when it's rolled out. You
don't have to design for the worst weather because you can always hide.

You can't do that for a static structure. The Hyperloop is an attempt to marry
the challenges of rocketry to the standards of civil engineering. The
advantage is you don't have to think about aerodynamics, which is good,
because air is the worst. (You also get civil-engineering budgets.) The bad is
you can't hide from the edge cases.

If you want to grapple with this problem live, rent (or borrow) a thermal
camera and make a model. Aluminum or tin foil would probably work for
something on the window. I've only done this upright, to simulate storing an
unfuelled vehicle outdoors in "ready-to-launch" mode, but you'll run into
similar problems with a horizonatal configuration. At first, the shade works.
Then thermals develop. You can foam it, and that looks like it works for a few
days. Then someone instruments the inside and, lo and behold, hot spots. Turns
out foam doesn't really help with heat that recurs in the same place, day
after day. (Our solution: slowly rotate it.) You could completely isolate the
tube, which is what NASA does in its vehicle assembly building [1], but at
that point you might as well (a) bury it or (b) have a fleet of Concordes
flying on loop, because either will be cheaper.

I'm not saying it's impossible. But it's much harder than the pressure
problem, which is itself hard to get economical. If you want the tube above
ground, I don't think it works with existing materials. My criticism of the
Hyperloop One project is they didn't bother solving these issues with models.
(Note: this is how Elon did it with the Falcon 1.) Instead, they decided to
build a maglev track.

[1]
[https://en.wikipedia.org/wiki/Vehicle_Assembly_Building](https://en.wikipedia.org/wiki/Vehicle_Assembly_Building)

~~~
kbenson
So, to make sure I understand the problem correctly, you expect thermals to
develop under shaded portions that still cause heat, and that to affect the
structure's top and bottom heat differential to a degree that it would still
cause problems? Is this different than oil pipelines because of the low
pressure and lack of a heat transferring medium to even the temperature of the
tube? I'm trying to figure out how this would affect a proposed hyperloop
system, when it seems sufficiently solved for other above ground pipeline
systems.

I can see relative size, inside medium, building material differences, shading
structures and acceptable tolerances all affecting the outcome one way or the
other, but I'm not sure to what degree each one would affect the outcome, so
I'm not sure if it's actually as hard as you make it sound or whether a
solution is known and achievable.

~~~
JumpCrisscross
> _Is this different than oil pipelines because of the low pressure and lack
> of a heat transferring medium to even the temperature of the tube?_

Most hydrocarbon pipelines run HTHP: high temperature, high pressure. This
keeps their contents viscous. That, in turn, means heat emanates relatively
uniformly from inside the pipe. For pipelines subjected to asymmetric
expansion ( _e.g._ when starting up or shutting down), they "walk".

"Walking behaviour occurs as the pipeline is heated, and expands
asymmetrically, until the point when pipeline expansion is fully mobilised.
Expansion is ‘fully mobilised’ when a virtual anchor forms near the centre of
the pipeline. The virtual anchor is then stationary, while pipe to each side
expands away from the anchor as the temperature continues to rise. Once
expansion is fully mobilised, walking ceases for that cycle." [1] As long as
it walks laterally, pipeline owners tend to be fine with it

The solution to walking is typically _laissez faire_ (taking care to ensure
the deformation occurs laterally, _i.e._ side to side, versus sticking a butt
up into the water.) Needless to say, this isn't an option for the Hyperloop.

Granted, the contents of these pipes operate at 130º to 170º C. They're also
narrower, resist a smaller pressure differential, face fewer such asymmetric
events and don't face the stress of capsules periodically whizzing past inside
them. Our tube won't displace by meters. Its displacement, moreover, won't be
problematic on day one. But over time it will critically weaken known
materials. Big, dynamically mechanically stressed, close to vacuum and above
ground is hard.

[1]
[https://www.researchgate.net/profile/David_Bruton/publicatio...](https://www.researchgate.net/profile/David_Bruton/publication/283290905_Lateral_buckling_and_pipeline_walking_a_challenge_for_hot_pipelines/links/5630da4608ae13bc6c353166/Lateral-
buckling-and-pipeline-walking-a-challenge-for-hot-pipelines.pdf)

------
manigandham
The engineering has never been a problem, vacuum-tube trains are an idea
that's been around for centuries. [1] Removing friction and air resistance is
a simple physics problem, and there are already operational maglev [2] trains
so putting them in a low-pressure tunnel is not a major revolution.

The real issue is the _viability_ of such a transport because of the cost,
complexity, and construction effort involved. We (in the USA) can barely build
a high-speed rail line effectively so a Hyperloop competing with existing
transportation options doesn't make economic sense currently. Take a look at
what happened to the Concorde program for a similar example of great
technology that just couldn't survive as a commercial service.

1\.
[https://en.wikipedia.org/wiki/Vactrain](https://en.wikipedia.org/wiki/Vactrain)

2\.
[https://en.wikipedia.org/wiki/Maglev](https://en.wikipedia.org/wiki/Maglev)

EDIT: Yes, the engineering effort is not easy, but the science is pretty
straightforward. We're not discovering new physics here...

~~~
idlewords
"We can barely build a high-speed rail line effectively...'

There is no high-speed rail line in the United States. The nearest thing to
high-speed rail is the Acela Express, which hits 240kph on 40km of track. But
this is weaksauce by modern standards.

~~~
Pxtl
And honestly, if you want to solve the USA's environmental problems, 200kph
commuter rail would probably be a better investment than HSR or Hyperloops.

~~~
ant6n
Definitely agree that more, better transit would have a much bigger impact.

But I'd say the problem of commuter rail is frequency, coverage station
locations, acceleration, level boarding, dwell times etc etc. Given that line
speed is dictated by acceleration and dwell times, top speed is really far
down the list of priorities.

Also, top speed of commuter rail is already up to 200km/h (e.g.
[https://en.wikipedia.org/wiki/ALP-45DP](https://en.wikipedia.org/wiki/ALP-45DP)).

~~~
Pxtl
I guess it's just my own experience in Ontario - the GO transit trains look
like they travel at about 110kph or so, and once you figure in their slow
acceleration and frequent stops that means they're quite slow. Outside of the
worst part of Toronto rush hour (which is notoriously bad) they're actually
slower than the comparable coach bus from my area (Hamilton).

The overall average speed is a paltry 50kph.

When the train is slower than the coach bus, why even have a train?

~~~
ant6n
The average speed is governed by acceleration and dwell time - the issue for
GO is lack of electrification (which increases acceleration), and lack of
level boarding (which decreases dwell time).

50km/h average is actually quite fast. I mean, a radius 50km from downtown is
a huge area already. We have to densify inside that radius, not sprawl people
further out because the trains are so fast. This means for example we need
more stations, so that more developable land is within walking distance of
service.

~~~
Pxtl
> This means for example we need more stations, so that more developable land
> is within walking distance of service

That's what lrt and subways are for, not the big commuter GO trains.

~~~
ant6n
That's the crux of what's wrong with commuter rail thinking in North America:
"Serving the city is what the subway is for". Your original post, asking for
200km/h commuter rail, is a sign of it.

There's a meaningless separation of modes based on technology, and ascribing
attributes to them. In Japan or Europe, the technologies are converging and so
are the modes. Any infrastructure will have it's utilization maximized, and
may function as what North Americans understand as 'commuter rail', subway' or
'light rail' all at the same time.

The result: more coverage, more service, better integration of services, more
overall effectiveness, more ridership, less reliance on driving.

------
dmix
Despite the fact there are more billionaires than ever, it's funny how small
the group of bold innovators are. It always seems to be the same few people.

~~~
dx034
I'd argue that Bill Gate's work has a better return of investment for society.

~~~
larkeith
IMO, we need both types - Gates' work improves society in our current world,
while Musk and Branson's investment kickstart the scientific and technological
advances needed to further our civilization.

------
Animats
When does Hyperloop One get a go on the Dubai - Abu Dhabi line?[1] That's
quite feasible. Straight route across flat, open desert.

Hyperloop One is a maglev vactrain. It doesn't "fly" aerodynamically, like
Musk's original plan. This means a more expensive track in the tube, but
higher riding height. Musk's original plan required a ride height of 0.3mm to
1.3mm, which means a really smooth tube. Maglev clearances are typically 1-2
cm, which is much easier to maintain over many kilometers of tube. Also, only
the track has to be flat; the tube can have seams and expansion joints, so it
can be fabricated by standard piping techniques. Vehicles can draw power from
the track; Musk's original design was battery powered. Maglev track is
expensive, though. That's why maglevs are rare.

If somebody in Dubai has the money, there's no reason it shouldn't work. Japan
already has 42km of maglev running, part of the Tokyo-Osaka maglev route under
construction, with full-sized trains. That's mostly in tubular tunnels.
Hyperloop One is easier than that.

Hyperloop One's test track uses a 3.4 meter tube, instead of Musk's original
2.4m tube. Maybe larger in the production version. Musk's very optimistic cost
proposals are based on his undersized tube. Hyperloop One will work, but it
may not be all that cheap.

[1]
[https://www.youtube.com/watch?v=3fu-6IDp3Fo](https://www.youtube.com/watch?v=3fu-6IDp3Fo)

------
batrat
I see so many negative comments about this, but in my opinion everything has
to start somewhere. It doesn't matter how crazy and impossible it looks, it
will be done eventually (and we have plenty of examples).

Maybe we will not teleport in 2 seconds across the globe or this project will
die, who knows if we don't try.

A little bit of optimism doesn't hurt. Just saying.

And for Virgin, it's not my money, if they want to invest in a black hole sure
they can.

~~~
christophilus
It's been said before elsewhere, but HN is the place to go to find out why
your project will never succeed. I've seen many successful projects crapped
all over here when they were in their infancy / pre-success days. "Stripe?! 3%
fees! So dumb. We already have lots of payment gateways. It's not hard. You
just have to {list of many tedious manual steps}..."

~~~
ferdbold
My favorite is Dropbox. "Store all my personal and/or corporate files on some
third-party server?! DOA."

~~~
austenallred
[https://news.ycombinator.com/item?id=8863](https://news.ycombinator.com/item?id=8863)

> For a Linux user, you can already build such a system yourself quite
> trivially by getting an FTP account, mounting it locally with curlftpfs, and
> then using SVN or CVS on the mounted filesystem. From Windows or Mac, this
> FTP account could be accessed through built-in software.

This sounds like such an insane proposition relative to the Dropbox we know
today.

The top comment is being pedantic that it doesn’t _technically_ replace a USB
drive because you have to install software and have access to the Internet.
Hilarious in retrospect.

If the biggest complaint someone can have is “you have to have Internet”
you’re doing OK.

~~~
lmm
> This sounds like such an insane proposition relative to the Dropbox we know
> today.

Does it? If you used WebDAV then you can mount a share in Windows or Linux
even over the Internet, and windows at least is good at caching it while
you're offline for short periods. For someone who has their own always-on
Apache it seems like this would replicate most of the use cases for Dropbox. I
think the point that's being missed is simply that most people would rather
see a few ads or pay a small fee than administer their own Apache, not that
what Dropbox offers is technically so far ahead.

~~~
austenallred
> For someone who has their own always-on Apache

I’m just guessing on numbers, but that probably describes <1% of the
population. Most people think Apache is a word used only to describe
helicopters.

~~~
KGIII
A small point really, but I'm not sure most people would only think it
describes helicopters. I am guessing most people would think it is a tribe of
Native Americans.

I admit that it's just a guess, but it does seem likely.

Again, not a major point.

------
peter303
Hope it fares better than Virgin Galactic which is at least eight years behind
schedule (first commercial flights proposed for 2010).

~~~
jandrese
Didn't Virgin Galactic go on hiatus after the test pilot died?

------
excalibur
....Are they going to rename it in the future based on the number of pods that
have gone through its tubes?

------
leke
I see they are using the term "extremely low pressure tubes" instead of vacuum
tubes.

------
SubiculumCode
I know there are feasibility questions, but have you thought about how such
travel could affect the course of U.S. politics?

One could feasibly live in Utah where land is cheaper, but still commute to
California for work. This would both lead to a purpling of many red states, as
well a providing a path for interior state natives to find good jobs in
coastal city centers.

Knowing the status of American politics where highly populated coastal states
are overpowered in the Senate by the seats of the near empty states in the
interior, one can see that if the potential for hyperloops is realized, there
will could very well be a massive shift of power back to the populace with
more equally distributed representation.

------
alexozer
Keeping a plain miles-long tube at at least 90% vacuum seems pretty hard to
me, especially when needing to deal with evacuations and possible breakages.
Why not divide the tubes into discrete sections gated by movable airtight caps
that side away while passing through? If one section repressurizes due to
evacuation or some other fault, so be it.

~~~
maxerickson
If you have a breakage or stopped capsule you anyway have to shut the whole
thing down.

------
mtgx
How safe would the hyperloop be from tube implosion?

[https://www.youtube.com/watch?v=T9bpUfWy8Wg](https://www.youtube.com/watch?v=T9bpUfWy8Wg)

I guess it would depend on how well they engineer the whole system, but who's
going to watch over the hyperloop building companies to do that right?

------
platz
I could see investors wanting to fund this simply for the PR benefits; whether
or not such a system is actually viable.

Or, perhaps they'll spin a few technologies out of it.

Or, perhaps they want to grow a network of related companies+technologies that
they can re-purpose to another venture in the future.

------
uptownfunk
Lots of comments about how this is not feasible, but wasn't spaceX's vision of
a reusable rockets similarly not feasible at the outset and they've since been
making some quite considerable progress towards this.

~~~
lmm
A reusable rocket was not just feasible, it had already been done with the
Space Shuttle. "We'll do what the Space Shuttle did but 50x cheaper" is
ambitious to be sure, but it's not at the same level as "we'll do this
completely new thing that has never been done before".

------
spacecity1971
I wonder if the tube could be continuously woven from carbon fiber and given
an aerogel insulating wrap, then the interior coated with ceramic? This would
perhaps mitigate heat expansion issues.

------
mannanali413
I bet with Hyperloop One becoming `Virgin Hyperloop One`, the hospitality and
the customer care experience will surely be awesome, thanks to the Virgin
Group :D :D

------
_zachs
Imagine if half of these commenters were around when the Wright brothers were
pioneering aviation?

~~~
mrguyorama
This kind of skepticism would have been perfectly acceptable had the Wright
Brothers wrote three pages of guesswork and napkin math instead of actually
building a plane.

~~~
kowdermeister
> instead of actually building a plane

[https://www.youtube.com/watch?v=jjv7bB9hy0k](https://www.youtube.com/watch?v=jjv7bB9hy0k)

------
a-b
I’ve been curious for a while if hyperloop and boring company are
complimenting each other.

------
ada1981
Didn't expect to see Dick putting his name on this one...

------
Apocryphon
I guess one of the silver linings of living in a "cyberpunk neo-Gilded Age but
with better UX than '80s cyberpunk" world is that dueling tech magnates might
accidentally craft something that could help society.

------
ovrdrv3
Anyone else see Branson on Shark Tank the other night?

------
glbrew
Great youtube video that presents huge barriers to the hyperloop:

[https://www.youtube.com/watch?v=RNFesa01llk](https://www.youtube.com/watch?v=RNFesa01llk)

------
arketyp
I feel that name has got to be a double entendre.

~~~
sova
Seeing as it'll be the first hyperloop? Or are you talking about the maiden
voyage?

------
kegan_myers_asy
VH1 rises again.

------
yahna
I wonder where this company would be if the original paper was written by
pretty much anyone other than Musk.

------
saosebastiao
Everybody talks about the engineering challenges, which have been beaten to
death. Elon Musk has a pretty respectable track record of making things that
seem technologically infeasible and making them happen. He's not in charge
anymore, but I trust that he wouldn't put his name on something that's not
possible. Even if it wasn't possible, I'm not the person to make that
critique.

The bigger challenge, IMO, is economic. High speed trains make a lot of money,
but their revenue has little to do with competing with airlines over
significant distances between large cities, which is what the Hyperloop is
attempting to supersede. The financial success of high speed trains has much
more to do with their ability to rapidly start and stop in lots of
intermediate urban areas within a corridor. I know this goes against the
popular narrative about why high speed trains are popular (OMG they can
compete with air travel!!!), but the narrative is wrong.

The revenue of HSR has a lot more to do with the number of cities that it
services than the end to end speed. If you look at ticket revenues on
successful HSR lines, terminus to terminus tickets typically make up <15% of
total revenues. The rest is made up by the remaining cartesian set of city
pairs. Even if you could add up all _possible_ market share (trains, planes,
cars) between terminus cities, it would still be less than the total revenue
for that line, due to the additional cities it serves. Even with the gradual
growth in power levels for high speed trains, with some now capable of 360kph,
end to end speeds have basically gone unchanged. What has changed with more
powerful trains? The lines have more stops now...they serve more cities, with
the higher power levels used for faster acceleration and deceleration. More
cities means more revenue, whereas higher speeds have already hit strongly
diminished returns.

Maybe with Hyperloop being really fast could _grow_ the market _and_
monopolize market share between Alpha cities, but that would still be a
stretch if the goal is economic viability. People see hyperloop, they crave
its speed, but the costs are too high and revenues are too low to just serve
the endpoints. But if you decide to serve intermediate cities, you slow it
down, and it no longer becomes the object of technological lust, and nobody
will want anything to do with it.

Among economic historians and _really nerdy_ train enthusiasts like me, this
isn't a contentious point. The same economic delusions were a primary
causative factor in the overhyping of railways during railway mania, best
exemplified in chapters 16-20 of Collective Hallucinations and Inefficient
Markets: The British Railway Mania of the 1840s [0], which is a masterpiece of
economic history IMO. Anybody in charge of building out some version of
hyperloop should do themselves a favor and read it, and then work on not
repeating history.

[0]
[http://www.dtc.umn.edu/~odlyzko/doc/hallucinations.pdf](http://www.dtc.umn.edu/~odlyzko/doc/hallucinations.pdf)

