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Hyperloop Alpha [pdf]

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Re: Hyperloop Alpha [pdf]

#171
post #110

Earlier quoted context omitted.

Sometimes practical considerations preclude using the most "preferred format". Will editing this white paper really be a significant obstacle to deploying a system like the one it describes? Conversely, does anyone ever release a white paper in LaTeX only?

What are you on about? No one here is saying that an open-source project to assist with Hyperloop could not be launched. Nor that the ability to edit the whitepaper that was released has anything to do with this proposed open-source project. Nor even that people typically release whitepapers only in LaTeX format. However if an open source project will be launched with Hyperloop then its success will be at least somew…

mpyne you're hilarious.

Re: Hyperloop Alpha [pdf]

#172

Earlier quoted context omitted.

Pretty sure you can truck pylons if you can truck in precast bridge decks: https://www.google.com/search?q=precast+bridge+deck

Concrete is about two tons per yard. The legal limit on most trailers is about 20 tons (40,000 pounds, the trailer is about 40,000 for the legal limit of 80,000 pounds). So you can get about 10 yards of concrete in one go; you can use specialty trailers to get higher numbers, but even if you double it to 40 tons, that's still only 20 yards. a 4' x 4' x 8' ecology block is about five yards. So let's picture the pylon…

If there was an interstate running directly from San Francisco to Los Angeles along this route...

Umm, that's kind of the point. It's called I-5.

Re: Hyperloop Alpha [pdf]

#173
post #149
post #17

The focus from people on bathrooms is puzzling to me. I've been on buses, without facilities, that go for hours without stopping. This is a 35 minute ride with restricted movement, if you greatly fear being able to hold it for that long, there are other, less efficient methods of transport to accommodate you.

It's a very small space, with no apparent facility to handle not just #1 and #2, but severe gastric distress. The other passengers then get to look forward to up to 25 minutes in that closed space. There's no stewardess, no way to stop the vehicle. An "emergency evacuation module" shouldn't take much room.

The design incorporates very powerful air compressors and water pumps, and generates, transfers, and isolates a great deal of heat. The cabin will be very well-ventilated, because if it weren't then passengers would die of something other than methane poisoning.

Re: Hyperloop Alpha [pdf]

#174
post #104
post #69

Earlier quoted context omitted.

did you read the paper?

Not every word, I have a day job. If you have something specific to contribute please share.

The proposal is to use turntables. Since emphasis is made in the paper on maximizing turning radii, it could be that the train is not intended to be able to turn sharply enough to negotiate a feasible "loop".

Re: Hyperloop Alpha [pdf]

#175
post #106

Looks like a good idea, but the major glaring technical point that seems to be missing is the issue of horizontal stability within the tube. When you get very low friction, high speed and no tracks, you're going to start having attitude problems without the right control surfaces available. Don't want to be spinning passengers around the roof of that tunnel!

The train could be just very bottom-heavy.

Re: Hyperloop Alpha [pdf]

#176
post #145
post #17

The focus from people on bathrooms is puzzling to me. I've been on buses, without facilities, that go for hours without stopping. This is a 35 minute ride with restricted movement, if you greatly fear being able to hold it for that long, there are other, less efficient methods of transport to accommodate you.

Well it's not just a matter of bathrooms. Even on a commuter bus or plane, if someone has a medical emergency and needs to get off right now , the bus will pull over or the plane will land. In this design you'd have to just sit there, helpless, until the vehicle reaches its destination. Heck, even if you're a doctor in the next seat you wouldn't be able to get up and help your fellow passenger.

Yeah, I believe this is the best point in the argument against pod transport. Even taking doctors out of the equation, if someone were to go into cardiac arrest on a plane, pretty much anyone on the plane would be qualified to operate an automatic external defibrillator and all flight attendants are required to be trained in CPR. The opportunity for first aid in this situation is the difference between life and death and it is unavailable in this pod design. 3 minutes without oxygen to the brain and serious brain damage is likely; 15 minutes without oxygen and you're pretty much guaranteed never to recover if you aren't already dead. If you have a cardiac episode on the hyperloop and need to be resuscitated, there's a good chance that the only good that those EMTs will do when the train arrives at its destination is to remove your dead body from the train.

Re: Hyperloop Alpha [pdf]

#177
post #56
post #42

Earlier quoted context omitted.

What will probably happen is that you get a transparent car and advertisements on the inside of the tube.

That fly past a metre from your face at 1,000 km/h!

On the Beijing subway there are adverts on LED displays on the tunnel walls that move along with the train, keeping pace outside the windows.

Re: Hyperloop Alpha [pdf]

#178
post #21

If the U.S. doesn't take this on, I hope another country with a big appetite for enormous public transit projects takes this on. Japan, Korea, and China, I'm looking at you...

The Republic of Texas would be a good fit. But Southwest Airlines is located here so it would never get through the legislature.

Re: Hyperloop Alpha [pdf]

#179
post #55
post #17

The focus from people on bathrooms is puzzling to me. I've been on buses, without facilities, that go for hours without stopping. This is a 35 minute ride with restricted movement, if you greatly fear being able to hold it for that long, there are other, less efficient methods of transport to accommodate you.

If not using the bathroom for an hour is an issue you should see a doctor. Not only are there good treatments to alleviate this, but it may be an indication of a serious medical problem. Get it fixed then enjoy life including perhaps the Hyperloop.

There are conditions with no cure that make it difficult to go an hour without using the bathroom. I think the people with those conditions are well aware that it's a "serious medical problem" without your advice.

Your post was about as useful as telling someone in a wheelchair to see a doctor to get their legs fixed (hey, it may be an indication of a serious medical problem!)

Re: Hyperloop Alpha [pdf]

#180

Earlier quoted context omitted.

Pretty sure you can truck pylons if you can truck in precast bridge decks: https://www.google.com/search?q=precast+bridge+deck

Concrete is about two tons per yard. The legal limit on most trailers is about 20 tons (40,000 pounds, the trailer is about 40,000 for the legal limit of 80,000 pounds). So you can get about 10 yards of concrete in one go; you can use specialty trailers to get higher numbers, but even if you double it to 40 tons, that's still only 20 yards. a 4' x 4' x 8' ecology block is about five yards. So let's picture the pylon…

I guess we can agree that we don't need to have this discussion, as I-5 runs the entire route where the pylons would need to be installed.
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