Hyperloop and other vactrains

[chrsjrcj]

When it comes to Hyperloop, I'm waiting for proof that it HAS failed, since prototypes are already exceeding 100 mph.
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We already have high speed trains, maglevs, and airplanes that regularly exceed that on a daily basis, while actually carrying fare paying passengers.

[mtuandrew]

Update on Musk and his Loop/Hyperloop/Boring Company contract with Chicago https://www.npr.org/2018/06/15/62047109 ... -questions

[electricron]

When it comes to Hyperloop, I'm waiting for proof that it HAS failed, since prototypes are already exceeding 100 mph.
He's already impressed enough people in Chicago to win THAT contract.

100 mph isn’t the promised 300 or 400 mph. HSR trains already go over 200 mph. 100 mph speeds don’t improve the state of the art.
Winning a contract doesn’t mean it will work. Come back after the project has been built and entered service and report how much better it is.

[lpetrich]

That link with its title: Chicago's Hyperloop Announcement Met With Questions : NPR

SCHAPER: Musk says his company's boring technique will dig the tunnels many times faster and cheaper than conventional tunneling. But both that technology and the autonomous vehicles are unproven.

I'll believe it when I see it about the tunnel boring.

As to the vehicles, there are plenty of existing ones that can do the target speed of 150 mph. They are high-speed trains.

[ConstanceR46]

Yeah, the most rabid fans will keep unrealistically dreaming of things "just around the corner". But I wouldn't underestimate Musk. When you look at the list of things he's done that Nobody Has Done Before, it's impressive. The *one* thing he has *repeatedly* failed to do is estimate time properly. But, then, it's hard to come up with a planning schedule when you have no examples of one before you. I mean, this is a guy who started his own rocket company with his own money, invented his own rockets and now outperforms NASA, Roskosmos (the Russians), the Chinese and ULA. Never mind what he's done for Tesla (full disclosure, I'm a Tesla stockholder and own a Tesla Model 3).

Except he hasn't outperformed Roscosmos until we have a Dragon carrying crew docking fully-automated to the ISS, AKA the same thing Roscosmos has been doing for years. Tesla is literally a union-busting hellscape that is making Model 3s in tents.

When it comes to Hyperloop, I'm waiting for proof that it HAS failed, since prototypes are already exceeding 100 mph.

A T-1 steamer could have topped that. Hell, a E6 atlantic could top that, and a E6 can carry a lot more.

[bostontrainguy]

The tunneling is the hardest part. Once a very straight tunnel is built between two points the cheapest thing to do is put in tracks and run a train. Makes no sense to do anything more. Why risk using unproven expensive technology?

[mtuandrew]

I’m having trouble understanding how his tunneling apparatus is any better than a conventional TBM, except that he makes smaller tunnels and doesn’t really have underground stations. In reality, he’s building a 100mph version of the Chicago Tunnel Company.

Also, Musk’s “Loop” concept doesn’t include high-vacuum tunnels, only the Hyperloop does that. Wouldn’t be enough time to reach anywhere near top speed between the Chicago Loop and O’Hare or Midway.

[lpetrich]

Narrower tunnels?

There is a certain problem with high-speed travel in a tunnel. A vehicle has to push the air out of the way. That is why high-speed trainsets have very aerodynamic ends. If there is not much space between the vehicle and the tunnel, then it will be hard to squeeze the pushed-aside air through it.

Consider the Gotthard Base Tunnel - Wikipedia, designed for 250 km/h travel. It uses twin single-track bores, and each one has a diameter of 8.83 - 9.58 m. Its tunnel clearance is 5.20 m (rail top to overhead conductor). From Loading gauge - Wikipedia, UIC GC loading gauge is 3.15 m width and 4.65 m height. This is plenty of space for pushed-aside air.

Urban-transit systems have narrower tunnels. For instance, BART's Transbay Tube has a diameter of 17 ft / 5.2 m. For equal width and height, this means an envelope with a width and height of 3.7 m, something that seems roughly correct. Measuring a picture in HSLRST / Archimedes Bridge Studies gives us:

Height of tunnel floor: 0.87 m
Width of BART train: 3.42 m
Height of bottom of BART train: 0.38 m
Height of top of BART train: 3.42 m
Max speed: 80 mph / 129 km/h

Cross-section fractions:
Gotthard Base Tunnel, GB C: 0.24
Transbay Tube, BART: 0.54

Some London Underground rolling stock seems like it closely fits its tunnel roofs, and it likely has a greater cross-section fraction.

[Literalman]

Makes no sense to do anything more. Why risk using unproven expensive technology?

Maybe it's intended to prove the technology. If hyperloop takes baby steps in Chicago and doesn't fail, then maybe Musk will get a chance to try it on a bigger scale somewhere else.

[ConstanceR46]

Makes no sense to do anything more. Why risk using unproven expensive technology?

Maybe it's intended to prove the technology. If hyperloop takes baby steps in Chicago and doesn't fail, then maybe Musk will get a chance to try it on a bigger scale somewhere else.

If it fails, Musk will call the CTA pedophiles.

[lpetrich]

In all that I've seen of the proposed Chicago tunnel, I see nothing that states that it will be evacuated. So it would be at full atmospheric pressure, and thus would not be a vactrain tube. As to the vehicles planned for it, I keep expecting its designers to rediscover the typical sort of rail vehicle.

[djlong]

Yes, he HAS out performed Roscosmos. More launches. Cheaper launches. More mass to orbit. Recovered boosters. As I write this, the next version of the Dragon, that will carry humans, has been built and delivered to NASA. Saying that Roscosmos hasn't been beat is like saying a team didn't win because 4-1 isn't a shutout.

And, yeah, that "union busting hellscape" is bursting at the seams with employees clamoring for those jobs. Unions have been repeatedly shown to be engaging is disreputable tactics to try and bust the ANTI-union sentiment.

Don't get me wrong, I fully support the right of employees to collectively bargain. However, many unions today don't have the best reputations - and the UAW is one of them. I work in an environment where the worst, most useless, borderline criminal employee gets to abuse the system and get the rest of us to do HIS work for several years - then when the system FINALLY starts to catch up to him, files a bogus sexual harassment suit - and, while railing against unions, he gets the union to help him keep his job.

Oh, and that Hyperloop concept you deride? Few days ago that record just went up to 290MPH in the latest competition. Boy, that's one hell of a failure. Sure, over time, maybe there's going to be something that makes it impractical but, until then, using the term "failed" (past tense) is more than a little premature.

[ConstanceR46]

> Unions have been repeatedly shown to be engaging is disreputable tactics to try and bust the ANTI-union sentiment.

Oh yeah i'm sure him not painting stuff yellow coz he doesn't like yellow and making people trek through sewage is just smoke and mirrors from the Unions.

>oh, and that Hyperloop concept you deride? Few days ago that record just went up to 290MPH in the latest competition. Boy, that's one hell of a failure. Sure, over time, maybe there's going to be something that makes it impractical but, until then, using the term "failed" (past tense) is more than a little premature.

A scale model. That can be beat by 15-year-old maglevs. Jeez, looks like i'm finished!

[mtuandrew]

Moderator Note: forgot to mention this when I rearranged threads, but enough about Musk and labor, Musk and Grimes, Musk and rockets, or anything but Hyperloop, Loop, and The Boring Company.

[djlong]

Consider the amount of money spent on maglevs versus the amount of money spent on Hyperloop. That's the whole reason for it. As much as I love maglev technology, the costs are stratospheric.

To try and stay on-topic, other companies related to The Boring Company have shown a track record of introducing new technology or perfecting and improving old technology to reduce costs DRAMATICALLY.

Like I said earlier, there may be something that comes out later that acts as a REAL road block to the adoption of Hyperloop technology. But, so far, it's looking good. Just over a year ago, the top speed in a competition was WAY under 100 MPH. Now it's knocking on the door of 300 MPH.