
We Think We Know What Elon Musk's Hyperloop Is - wtracy
http://www.businessinsider.com/what-is-elon-musks-hyperloop-2013-5
======
ricardobeat
This was the most thrown around idea right around when the Hyperloop story
came up. Nothing new here.

He also publicy said _“It is not an evacuated tunnel”_.

Previous discussion: <https://news.ycombinator.com/item?id=4815665>,
<https://news.ycombinator.com/item?id=4806059> and
<https://news.ycombinator.com/item?id=4813416>

~~~
FD3SA
Indeed, putting the old clues together with his new hints narrows it done
quite precisely.

It will be a Ground Effect lifting body on an electromagnetic rail. The lift
is provided by aerodynamic effects, and thrust is provided by electromagnetic
force.

Based on the details of the design, it would be capable of supersonic speeds
like the Concord, while employing Ground Effect like an air hockey table, and
propelled like a Rail Gun.

The biggest challenges will be keeping the vehicle stable and at a constant
distance from the power rail at high speeds, as aerodynamic disturbances can
destabilize the vehicle. Given Elon's expertise with rockets, this should not
be too difficult.

EDIT:

An prototype of a ground effect train:

<http://www.youtube.com/watch?v=EaOnrIRf_Mg>

Elon's will use electromagnetic propulsion instead of electric fans.

EDIT 2: I just realized this may be Elon's electric jet idea. He may use a
ram-air electric jet at high speeds, and only use the power rail to get the
vehicle to supersonic speeds where the ram-air engines are most efficient.
This would make it MUCH cheaper than maglev by eliminating the power rail on
the majority of the track.

EDIT 3: Rail gun diagram.

<http://www.howstuffworks.com/rail-gun1.htm>

The walls of the guideway will likely house the propulsion system.

~~~
cpeterso
But where could he actually build such a long, and presumably straight,
railway? He said the system has no "right of way" issues.

~~~
fian
The Nullabor plain in Australia?

Wishful thinking from a Perthite _sigh_

~~~
cpeterso
That would be a very cool way to traverse Australia. Do most travelers
circumnavigate Australia to get to the other side? I've seen some videos of
the "road trains" hauling six trailers across Australia.

------
deftnerd
A previous HN discussion brought up the possibility of a Launch Loop and
several descriptions of that proposal seem to fit very well.

A Launch Loop is an iron cable just 2 inches thick that runs inside of a
sheath at tens of thousands of miles an hour. The sheath has electromagnets
inside of it to accelerates the cable. The motion of the cable would cause the
loop to curve and raise into the sky.

To outside observers, it would look like a giant version of the St. Louis arch
with the peak nearly in low earth orbit, but only a few inches thick. The
magic comes with the fact that the iron cable can be used for travel by using
electromagnetic attraction to the iron cable through the sheath.

What's interesting is that while there are several engineering challenges,
unlike a space elevator, this wouldn't require any materials technologies that
don't already exist today. The iron cable could be made by existing forges
that make the cabling for bridges, and the electromagnetic sheath could borrow
a lot of existing technologies from the hard drive manufacturing industry.

It would also fit with his previous work on Space X and Solar Cities to some
extent.

A launch loop can be used to transport cargo or passengers high enough that
the energy required to get them into orbit is very inexpensive, which ties
into his Space X work.

The external sheath of the Launch Loop could have solar panels on it to power
the electromagnets that help keep the loop in motion, and even when the sun
goes down, millions of tons of iron spinning like a flywheel has enough
kinetic energy to keep going until the sun rises again.

I wouldn't be surprised if he ran across the concept when he was researching
ways to get into space before he founded Space X, and it's his "Step 2".

Lastly, if you had a giant cable stretched across the sky that worked kind of
like a bicycle brake cable in its sheath, but the cable was running through
the system at 30k mph in a giant loop, what better name than Hyperloop? It
also explains why a trip that he describes as being twice as fast as an
airplane would take 30 minutes. It takes more time to go to LEO and back down

Keep an eye out for Musk buying any patents on electromagnetics or him buying
a oceanic cable-laying ship.

<http://en.wikipedia.org/wiki/Launch_loop>

~~~
hansy
Musk explicitly mentions, "If you put solar panels on it, you generate more
power than you would consume in the system. There's a way to store the power
so it would run 24/7 without using batteries." [1]

[1] [http://www.theverge.com/2013/5/29/4378468/elon-musk-
teases-j...](http://www.theverge.com/2013/5/29/4378468/elon-musk-teases-june-
news-on-hyperloop-rapid-transit-system)

~~~
tripzilch
Maybe I'm reading over it, but the article you link doesn't actually seem to
contain that quote?

~~~
mkr-hn
It's just before the tags and comments.

------
rayiner
You have to love a guy you looks at massive, capital-intensive projects and
thinks "I should do that" instead of "shit let's do something easier."

~~~
jwr
Elon Musk looks increasingly like someone straight out of Ayn Rand's work.
He's the present day Ellis Wyatt or Henry Rearden, tackling grand projects
that others shy away from.

He deserves respect just for that — looking beyond the next quarter's bottom
line. Just look at the contrast this creates with all the managers whose plans
for the next quarter are "let's spend slightly more on marketing".

~~~
alphydan
well, Ayn Rand modulo all the public money he uses in his ventures (state
environmental credits for Tesla, contracts with NASA ... ie. taxpayers money,
research grants, etc, etc). Then again Ayn Rand did suck state bottle with
medicaire and social security. I'm not saying the projects are not ambitious
and amazing. But they would not grow so quickly without the State.

~~~
ricardobeat
[http://www.teslamotors.com/about/press/releases/tesla-
repays...](http://www.teslamotors.com/about/press/releases/tesla-repays-
department-energy-loan-nine-years-early)

~~~
tptacek
(a) They were financially incentivized to repay early.

(b) They got the sweetheart-deal to end all sweetheart-deals: a gigantic cash
infusion structured as a loan with a market-beating interest rate, rather than
as equity which would have entitled the government to a share of the upside.

~~~
ricardobeat
Isn't that a standard deal as far as government loans go? It's nothing
compared to the auto industry bailouts, where even the equity taken turned up
a loss.

~~~
tptacek
I'm not sure how the government intervening even more in different companies
has anything to do with my point.

------
cookingrobot
As long as we're guessing, here's my idea. An electrically propelled train in
a tube. Instead of evacuating the tunnel you have ducts in the walls that vent
the high-pressure air from in front of the train to the low-pressure
sides/bottom/rear of the train. This should reduce the energy wasted trying to
push a shockwave through the tunnel, and would use the air pressure to keep
the train off the walls. This would fit with his "air-hockey" comment, and
wouldn't be an evacuated tunnel - which he said it isn't.

edit: And the "loop" part of the name is because the air ducts are loops the
same length as the train. They move the air directly from in front where it's
high pressure to the rear where it's low pressure.

~~~
nitrogen
My guess: Musk is throwing random keywords at the Internet, then feeding all
the speculative ideas generated by smart geeks to his engineering team until
they come up with the real product ;-).

~~~
nitrogen
After I posted this, I noticed a top level comment with the same idea from an
account that's been dead for nearly two years, apparently for posting an
Office Space joke:

 _stiller 3 hours ago | link [dead]

At this rate, Elon can simply wait until somebody comes up with a viable plan
and say, "yes, that's what Hyperloop was all along."_

<https://news.ycombinator.com/user?id=stiller>

------
ck2
This is like something you'd read in popular science a decade ago where they
are theorizing the 22nd century.

But people are very messy, annoying creatures.

Imagine all the social problems of a typical jet or subway ride today, now put
them in a closed tube across the country.

The ride may take 30 minutes but the TSA line will be an hour to grope you.

At best this would work for cargo. But we'll have automated, self-driving
semitrailers decades before this ever happens.

------
presspot
Standing on the downtown BART platforms you can't help but think about (and
literally feel) the massive amounts of air being pushed around by the trains.

An evacuated tunnel would do wonders for both efficiency and hair styles.

------
anologwintermut
Lets assume it is some kind of maglev in a buried tunnel. How does this effect
right-of-way? My understanding is the problem for building even a simple high
speed train from LA to SF is principally NIMBYism and the resulting lawsuits .
This causes costs to sky rocket as you get delays.

Does digging a tunnel underground solve that ?

~~~
venomsnake
I suppose the authorities will just use air travel as precedent - nobody needs
your permission to build air corridor above your house.

~~~
lmm
There were lawsuits over this when air travel was getting started.

~~~
twistedpair
Limits are above and below ground. The FAA has a limit of 2000ft on
structures. Beyond that you'll need to go to the mat to get special
dispensation to go higher.

------
oelmekki
> History has shown that some obvious projects, such as tunneling under the
> English Channel proposed in the time of Napoleon, can be delayed for
> centuries because of political pressures

I really don't see why, french empire and united kingdom were such good
friends :)

On a side note, I feel very sad to consider we could have a mean to travel the
world at cheap cost for four decades, and it still cost a salary and sometime
about 24h to go to the other side of the world. With all other things Musk has
talked about, it really makes think humanity seriously lags.

~~~
JackpotDen
If you want a good head screw, think about the Baghdad battery and the
Antikythera mechanism.

Now imagine if the Turing church hypothesis was figured out back then.

------
andymoe
He has already said it is not an evacuated tube though he chooses his words
very carefully in all the talks I've seen. It comes up in just about every
long interview he has done over the past year.

------
tachyonbeam
The article makes it seem like politics are the only problem. Another problem
is that this would be very very expensive. Magnetic levitation train tracks
are already expensive. How much is it going to cost to build a vacuum tunnel
with some sort of magnetic propulsion system built into the walls of it, not
to mention the supporting infrastructure (vacuum pumps, power distribution,
safety exits, maintenance tunnels)? Probably not achievable with the current
cost of labor and parts (and all the overbilling happening everywhere).

Then there's the danger. What if an earthquake happens? What if the tunnels
leak and air or water seeps in? What if your magnetic stabilization system
fails for a fraction of a second and your train floating at 14000MPH grazes
against the sides of the tunnel? If an accident happened in one of those
tunnels, it could easily kill everyone onboard, and disable the tunnel for
months.

It's a really nice and futuristic idea, the kind that would once again make
the world a smaller place (commuting from SF to NY for work, anyone?), but it
probably won't happen until we can really prove such a thing is safe, and we
change from capitalism to an economical model where we build things like this
because, you know, they're good for humanity as a whole.

Personally I think a project like this would be good for the American economy,
but then so would massive investment in solar power plants. Instead you guys
gave fat checks to the banks.

------
alwaysinshade
> Hyperloop is a “cross between a Concorde, a railgun and an air hockey
> table.”

I'm thinking Wing in Ground Effect [1], where small vehicles are launched to
supersonic speeds using electromagnetic slings (and perhaps then use their own
power to super-cruise to the destination and eventually decelerate). You
wouldn't need much infrastructure - the cost would be in the vehicles and
launching mechanisms.

[1] <http://en.wikipedia.org/wiki/Wing_In_Ground_Effect>

~~~
omegant
It must be inmune to weather and take into account that it will be supersonic
at least, so it must be covered. Also Elon is very good at going to the basics
of the problem like: -Cost of installing the system -pass rights -cost of raw
material -current state of technology (lots of legacy tech on transportation)
and "easy" improvements of Efficiency with improved implementation.

Given that thanks to his actual business he has great knowledge of high speed
aerodinamics, electromagnetism electrical propulsion and energy storage..

My bet is towards an elevated light tube (not vacuum) that works as a
induction propulsor for the vehicle and condensor battery(you may use solar
panels on top to recharge it). Also it insulates the "train-plane" from the
weather and the exterior from the sonic shock. The vehicle will be like a
electromagnetic train but just for impulsion and braking, it will use the
shock waves and ground effect to hold the weight and stabilization. That way
the electromagnetic fields don't need to be generated with expensive systems.
The tube could use high voltage lines right of way and some simple metal
towers to hold the actual system. I don't know if it makes sense but if
something like this really can work it will be way cheaper that current high
speed trains, vacuum capable tube or spinning megatons of steel at high speed
through highly populated areas(a mechanical failure has the capability of
wiping entire neighborhoods like a wire lawn mower).

------
IvyMike
Supposedly, sections of the East Side Access subway project in New York cost
upwards of one million dollars per foot. I can't imagine how much a vacuum-
sealed tunnel would cost.

~~~
potatolicious
The costs of East Side Access is almost entirely due to tunneling _deep_ under
one of the most heavily built-up areas on the planet, without disruption to
either above-ground or underground activities.

Musk's system, if it works, will cost a bundle on this fact alone. Any
corridor that would justify such a high speed system would also be stupidly
expensive to build through, both to acquire the rights to, and to construct
without completely destroying everything along its path.

------
rdl
I'd rather see something essentially a ramjet-in-a-tube, similar to UW's RAMAC
space cannon launcher. Essentially, a long tube filled with correct mixtures
of natural gas and oxygen, where a double-cone shaped projectile is
accelerated through external (railgun?) means into the breech, and then the
compression of gas detonates it right behind the projectile, accelerating it
like a ramjet at constant acceleration. For a shuttle, you deaccel by running
in reverse from midpoint. It'd be like $100 in natural gas to send 100 people
from SF to LA at mach. You'd have to build a low-pressure 1-4m diameter
pipeline, totally something we know how to do already for water pipes and
natural gas pipelines.

If I had $50mm (or access to that level of capital), I'd probably build one as
a LEO satellite launcher. Put 20kg satellites into LEO, full of Ka-band gear,
for $100k each, several times a day, 365 days a year. On the side of a
mountain in Kenya/Ethiopia/Somalia.

~~~
Groxx
Wouldn't you have to re-fuel the tube each time? Presumably this would cost
more than $100... and how would this work in reverse to slow down?

I would think (probably incorrectly, since I know next to nothing about it)
that a ram-based system would inherently have combustion primarily _behind_
whatever tightest-seal exists that's bringing the gasses up to combustion
temperature, since doing so would also mean the expansion pushes forward
against that seal. Or does simply sealing a bit better cause combustion in
front of the seal?

~~~
rdl
Actually I didn't think as much about how to do deacceleration correctly; you
wouldn't be able to just flip it around and do ramjet-style, you'd have to use
a progressively more sense fluid to fill the tube, which would create a lot of
heat. You could still do braking over a hundred miles, progressively, though.

The main goal (vs. a regular cannon) would be to spread the impulse over a
long acceleration area, not all at once like with an explosive-powered gun.
People would probably be happiest with <1G.

~~~
eterm
Accelerating to Mach at 1g takes 35 seconds during which you've gone nearly
6km (3.6 miles).

That's a long tube...

~~~
rdl
Not relative to SF to LA distance.

------
ubernostrum
So he's going into the burrito business?

~~~
bigiain
Exactly what I thought.

(For those not "in" on the joke: [http://idlewords.com/2007/04/the_alameda-
weehawken_burrito_t...](http://idlewords.com/2007/04/the_alameda-
weehawken_burrito_tunnel.htm) )

------
BuddhaSource
Elon Musk knows how to keep Tesla and himself in the news.

Tesla is successful so far only because of his strategic marketing. People
have build great stuff in the past but not really appreciated because they did
not market well.

There is huge learning from this. I personally like his execution.

~~~
pbreit
Don't forget that the car itself got the highest rating ever from one of the
most independent reviewing organizations in existence. But, yes, the marketing
is pretty terrific, too.

------
richtr
Since we are generally speculating here, is there any possibility the
Hyperloop could be a suborbital craft to escape the atmosphere and thus reduce
journey times dramatically.

That doesn't really work for "San Francisco to LA" but Richard Branson has
mentioned this as an objective for Virgin Galactic "within the next 20 years".
I'd be surprised if SpaceX, and hence Elon Musk, were not also looking in to
this considering the technology they are creating.

~~~
john_w_t_b
I hope this is it. Suborbital hops between cities would be a spectacular ride.
Minimal ground infrastructure needed also.

------
AliAdams
Successfully isolating from earth movements would be my biggest worry about a
project like that. The system is going to need a good bit of flexibility built
in.

------
danielmendoza
Odd that this article popped up on Yahoo today:

[http://news.yahoo.com/blogs/trending-now/futuristic-high-
spe...](http://news.yahoo.com/blogs/trending-now/futuristic-high-speed-tube-
travel-could-york-los-171007828.html?vp=1)

"A company called ET3 has plans in the works for the Evacuated Tube Transport,
a high-speed transportation tube that uses magnetic levitation."

------
Groxx
> _The VHST would have to be underground._

Anyone have any idea why? It seems to me like seismic shifting underground
would be many times worse than above-ground, if only because you have to dig
to make room (either before or after such shifts).

~~~
sounds
NORAD and the LHC are examples of successful underground projects that have
addressed the seismic issues.

I agree with you that to reach the level of safety consumers will demand, more
thought needs to go into it. But it's not impossible, which was kind of in
line with what the article was saying.

~~~
snogglethorpe
Note that Japan's Chuo Shinkansen is to be approximately 60% underground (much
of that "deep underground").

... and it's real-world, actually-being-built, long-distance (about 300km for
the first phase), safety-critical (transports passengers at high-speed),
market-financed project in a highly seismically active area.

<http://en.wikipedia.org/wiki/Ch%C5%AB%C5%8D_Shinkansen>

~~~
Groxx
That's only about half the speed that the hyperloop is being advertised at,
though. That route is claiming ~500km/h, which would put you from SF to LA in
about an hour, if this site is accurate:
[http://www.mapcrow.info/Distance_between_Los_Angeles_US_and_...](http://www.mapcrow.info/Distance_between_Los_Angeles_US_and_San_Francisco_US.html)

Which is not to imply that's not an incredible feat - the Shinkansens are
awesome, and _work_. Just that things get harder practically exponentially as
you increase speed, so doubling it is a very, very big jump.

~~~
snogglethorpe
Sure, I was just responding to the subthread about the feability of long-
distance precise/safety-critical tunnel-construction in seismically active
areas.

Nobody knows what hyperloop is anyway (and it's not even clear that Musk
actually has a real plan), so it's hard to say much about the details! :]

------
SuperChihuahua
While that article says it will take 21 minutes to travel from LA to NY, Elon
explained that the Hyperloop will make you travel from LA to SF in less than
30 minutes. It's a matter of definition, but I believe the Hyperloop is
slower.

------
Dnguyen
Can I build a generator on top of this? Since it's a metal object, I just need
to build some magnetic rings along the way, et voila!

