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Transport Expert Insists 'Don't Dismiss Wacky Hyperloop'
DavidGilbert99 writes "Since Elon Musk announced the details of Hyperloop earlier this week, we've seen a number of experts debunking the technology involved, but at least one is more upbeat about the possibility of 600MPH train travel. Speaking to Alistair Charlton at IBTimes UK, professor Phil Blythe from the Institute of Engineering and Technology said: 'My gut feeling is, don't dismiss it out of hand just because it sounds a bit wacky,' adding 'You're always going to have long distance travel, and if there was something that could replace air travel between cities and hubs, and is low carbon [with] low energy requirements, it make sense to explore it, it really does.'"
Land is going to be what kills this project, before it even gets as far as anything technical. How do you acquire the land for the route as a private entity, without eminent domain?
Every time you buy a parcel of land the neighboring parcels know they're suddenly worth a fortune to you, because you can't just go around them at 800 mph. You have to stay within safe and comfortable G-force maxima for your passengers, which means no more than gentle changes in routing -- and that means you'll have hundreds of hold-out roadblocks in the midst of your route, refusing to sell unless you can provide them with an instant and very comfortable retirement. And if you can't persuade them to sell... well, somehow you have to find a route around them, and buy even more property to make your new route happen.
And then there's the neighbors whose property you aren't buying who will mire you in lawsuits because they don't want an ugly Hyperloop system at the end of their property.
Land is going to be what kills this project, before it even gets as far as anything technical. How do you acquire the land for the route as a private entity, without eminent domain?
Somehow it didn't seem to be a problem when the railway was being built over Indian lands... *ducks*
Ezekiel 23:20
It doesn't matter if they were designed for it or not. They happen to be straight enough anyway, bar a very few locations. This simplifies the land grab issue thousands of fold. Given that this is being proposed as an alternative for a rail link that requires a land grab along its entire route, that's a massively simplified problem.
It's a sealed railroad at 5 times the maximum speed of a hypertrain. 25 times the kinetic energy, rattling the supports at speeds and over distances that have never been approached by any mechanical ground based vehicle, and completely vulnerable to mechanical failure or flaw at any point along its pth.
The stresses involved and reliability requirements are both an order of magnitude greater than any ground based transport system. Coupled with Not In My Back Yard for this swooshing deathtrap, It Ain't Gonna Happen.
The actual transit engineer certainly doesn't know how to think outside of the box ... And if you read his credentials, he's not a transit engineer (is there even such a thing?)... He's a civic planner who's been employed in his field for a short 7 years.
He says the headway is essentially restricted by the amount of time it takes for each pod to decelerate to a stop, close an airlock, pressurize the container, open the other airlock, etc ... Then trying to get the old arthritic passenget in/out of the pod in 60 seconds. Even I, a lowly firmware guy, can conceive of a few different ways to handle that. These are not huge obstacles on which to form the basis of analysis and reject the idea.
But when nothing around you changes for hours, it's hard to tell you're going that fast.
Take I-80 coast to coast. The big challenge is staying awake through 1000 miles of corn, but you'll start to appreciate just how much of it we grow.
Instead of repeatedly talking from ignorance, why don't you read Musk's proposal? It covers the use of the highway in detail, showing that there is no problem on the route he proposes.
Democracy is a sheep and two wolves deciding what to have for lunch. Freedom is a well armed sheep contesting the issue
"Flight by machines heavier than air is unpractical and insignificant, if not utterly impossible." - Simon Newcomb, 1902.
The main difference seems to be fuel usage and the lack of TSA rectal examinations.
Never fails. Smart people looking foolish by their own overconfidence. Yes, we know you're way smarter than the average knucklehead around you. And they have lame brained ideas all the time that you can quickly point out how dumb each idea is. It happens to all of us. But it only works with your local knuckleheads.
So just stop it. At the very least phrase your objection in the form of a question. And realize that the more obvious it seems to you the more likely it is that you are the one overlooking something.
So there's no secure area around the pylons? Anybody can just drive a tractor full of fertilizer right up to the pylons holding the tube up, and detonate at will?
"only need space for a pylon, and the rather large, fenced, secured area around it that will be off limits to everyone in perpetuity due to security restrictions," is what you meant.
And yes, that means the farmer will lose a big chunk of his land everywhere the pylon goes.
Or are they not going to secure these things at all? (And if they don't, what's the point in 'airline style security' to ride it? Nobody will ride it with a bomb when they can just drive a pickup full of fertilizer next to a pylon, and rig it to explode. Why be a martyr, when you can blow some people up and be home for lunch?
There are examples of maintaining a much much harder vacuum on this scale. All particle accelerators, including the LHC, are kept at a hard vacuum. The Large Hadron Collider is 27km long and 3.8 m wide, wider even than the proposed passenger + vehicle version of the Hyperloop. The large tunnel is kept at 10^-6 mbar (9.8 x 10^-10 atmospheres) for months at a time. The beam pipe is kept at "several orders of magnitude better vacuum."[Source [PDF]] The discussion of the beam pipe vacuum deals with how well the system removes individual hydrogen molecules.
So maintaining an industrial-scale vacuum is a solved problem, to much thinner vacuums than are necessary for Hyperloop. Mr. Musk's log scale plot of the effectiveness of vacuum pumps was intended to show where on that log scale the cost effectiveness of running pumps suddenly falls into a hole, to justify his choice of 0.001 atmospheres. I'm sure some effort and some experimentation would be useful to validate how many pumps set how far apart are needed to maintain the target vacuum, but the mathematical models definitely have exhaustive and detailed physical validation already.
Large scale linear electric motors also already exist and are already used in transportation. Tokyo's Toei Oedo Line is a subway that runs on linear electric motors. All together there are 11 subways in China and Japan running with linear electric motors. They run on wheels though, rather than air repulsion skids.
Both of your objections seem like solved problems to me. What I question is how well any system can be engineered to maintain tunnel smoothness well enough over time that the height of the tunnel floor never deviates by more than 0.5 mm along the length of the suspension skids over decades of operation. I don't know of any existing project that has maintained that degree of smoothness over such a distance. I suspect pylon design is critical to maintaining that smoothness, and the interior of the tunnel would have to be periodically resurfaced.