Hyperloop - Elon Musk's Alternative to High-Speed Rail

[Scott R]

.5 a G will likely kill some elderly or invalid riders.

[Pazuzu]

Originally Posted by Scott R

.5 a G will likely kill some elderly or invalid riders.

Why would they be on there in the first place?

This isn't a replacement for the city bus, it's a very specific resource to allow business between two very large commercial hubs. It will be filled with salesmen and such in suits, who will be visiting the LA office for the day instead of having a conference call. It won't be kids and grandmas and such, at least in the initial versions.

A 737 pulls (about) 0.2Gs at launch, no one complains about that, and that's sitting in horrible seats with no padding or support. Put some nice flat seats with bolsters, and you could run most people to 0.3 or 0.4 easily.

finally, no one will want to commute for 35 minutes while laying down in some sort of layered seating arraignment? I'm starting to think that some of you have never actually lived in a city and used a bus before, because the normal person commuting to work on the bus/train in a city like Chicago spends about 35 minutes standing, crowded in, with no bathroom breaks, no ventilation, and lateral acceleration forces that are dangerous. Compared to how some people go to work, this hyperloop deal would be a dream.

[1-ev.com]

Bugatti Veyron from 0 to 100 km/h in 2.4 s - 1.55 g g-force - Wikipedia, the free encyclopedia


Hyperloop would be like driving Bugatti Veyron - for FREE.... ...oh sorry we already wasted $3T USD...

[red-beard]

I read the 60 pages. If the temp rises only 40F, the tube system will expand 480 feet over 350 miles.

Wall thickness only needs to be .135 for 7'4". I guess they increased the pipe thickness to be "self supporting" over 100 feet spans with the full weight of the "car" in the middle. I'll run some calcs on that later.

I'll put some more stuff up later

[Scott R]

Originally Posted by 1-ev.com

Bugatti Veyron from 0 to 100 km/h in 2.4 s - 1.55 g g-force - Wikipedia, the free encyclopedia


Hyperloop would be like driving Bugatti Veyron - for FREE.... ...oh sorry we already wasted $3T USD...

Put a lot of handicap and elderly folks in Bugatti's do we?

[BlueSkyJaunte]

Originally Posted by 1-ev.com

we would be visiting cities across USA for FREE

Awesome, we can import our crime from other states as well!

[red-beard]

Originally Posted by Scott R

.5 a G will likely kill some elderly or invalid riders.

Originally Posted by Pazuzu

Why would they be on there in the first place?

This isn't a replacement for the city bus, it's a very specific resource to allow business between two very large commercial hubs. It will be filled with salesmen and such in suits, who will be visiting the LA office for the day instead of having a conference call. It won't be kids and grandmas and such, at least in the initial versions.

A 737 pulls (about) 0.2Gs at launch, no one complains about that, and that's sitting in horrible seats with no padding or support. Put some nice flat seats with bolsters, and you could run most people to 0.3 or 0.4 easily.

finally, no one will want to commute for 35 minutes while laying down in some sort of layered seating arraignment? I'm starting to think that some of you have never actually lived in a city and used a bus before, because the normal person commuting to work on the bus/train in a city like Chicago spends about 35 minutes standing, crowded in, with no bathroom breaks, no ventilation, and lateral acceleration forces that are dangerous. Compared to how some people go to work, this hyperloop deal would be a dream.

Mike, you need to acquaint yourself with the ADA...

No way someone will build one of these without a wheelchair ramp

[Pazuzu]

Originally Posted by red-beard

Mike, you need to acquaint yourself with the ADA...

No way someone will build one of these without a wheelchair ramp

Actually that's an interesting question.

Does (for example) a private company jet need to be ADA compliant?

OK, what if they made 1 of the dozen or so pods "accessible", and run it slower and with an extra gap between it and the pod behind it. Maybe it only hits 0.2G, gets to 500mph, and takes 55 minutes to arrive.

Minutia like that doesn't affect this design, but it does give the interwebs something to talk about

I will admit, when they first started talking about this, I figured it was a back of the envelope kinda deal, Mr. Musk would say "hey here I am with more grand ideas", but it's clear that he put a great deal of work into this before presenting it, far more than i expected, and far more than you would see for any other "pie in the sky" proposal like this. He knew that people would immediately try to destroy the idea, and had it hardened beforehand. Stress analysis of the pylons? Who does that at this point?

[Pazuzu]

Originally Posted by red-beard

I read the 60 pages. If the temp rises only 40F, the tube system will expand 480 feet over 350 miles.

TUBE temp, not ambient temp. So, prevent the tube from going up 40 degrees. Pre-heat it (they have pods full of steam and 1000 degree low pressure air, the entire system will probably run well above ambient, with only the pod interior conditioned, which is easier with a nearly perfect vacuum around it, no convective or conductive heat transfer between the cool pod and the hot tube...

[red-beard]

Originally Posted by Pazuzu

TUBE temp, not ambient temp. So, prevent the tube from going up 40 degrees. Pre-heat it (they have pods full of steam and 1000 degree low pressure air, the entire system will probably run well above ambient, with only the pod interior conditioned, which is easier with a nearly perfect vacuum around it, no convective or conductive heat transfer between the cool pod and the hot tube...

It doesn't matter, there will be changes due to thermal expansion/contraction.

Also note the 3 mile radius curves. That will mean that as you go up over the Grapevine, you will need to raise the tube far above ground before it starts to rise in altitude.

I am skeptical of the air bearing. I also think he is seriously underestimating the cost of the project at $6B. If he can do it for $6B and $20 per trip will make it pay back, he should be able to charge easily $50 or $100 and make a mint.

[RWebb]

re air bearing - what would it take to incorporate some addition such as a maglev effect?

cheaper than on a train?

[Scott R]

Originally Posted by RWebb

re air bearing - what would it take to incorporate some addition such as a maglev effect?

cheaper than on a train?

Of course, fewer moving parts correct?

[Pazuzu]

Originally Posted by RWebb

re air bearing - what would it take to incorporate some addition such as a maglev effect?

cheaper than on a train?

Maglev requires 2 things, lots of electricity, and magnets run along the entire length of the tube. Why add a system that is (a) expensive, (b) hot and (c) heavy?

The idea behind this is that there is no propulsion along 95% of the track, so the infrastructure is very simple. Similar to why long distance trains don't derive power from the tracks, keep the "road" a dumb system and make the "vehicle" smart, rather than the other way around (as seen in something like a subway).

Also, Maglev requires a very precise path, while the air bearing allows the pod to float along the inner skin of the tube, like a luge (it would work it's way up the side during turns). Maglev can't do that. The air bearing will work at a range of speeds, which will give it a range of actual paths along the tube wall.

If we had cheap room temperature superconductors, this would all be an intellectual dalliance since we would have maglev systems crisscrossing the nation, but we don't have that.

[Pazuzu]

Originally Posted by red-beard

I also think he is seriously underestimating the cost of the project at $6B.

Of course! But, play the financial calculus game. If this project can be done for any total cost less than the train project, give any results better than the train project, have a downtime and accident rate less than the train project...then it MUST supersede the train project. Especially if it can be privately funded as a privately owned transportation system, which I would be 100% for, or a private company run via government contracts like SpaceX (and Tesla for that matter...).

[Scott R]

The math is not working out on the water weight required for the pod. It's for coolant, however the system vents steam, but only at a station. The amount of water needed is going to be very heavy, probably to heavy to be feasible.

[red-beard]

Originally Posted by Pazuzu

Of course! But, play the financial calculus game. If this project can be done for any total cost less than the train project, give any results better than the train project, have a downtime and accident rate less than the train project...then it MUST supersede the train project. Especially if it can be privately funded as a privately owned transportation system, which I would be 100% for, or a private company run via government contracts like SpaceX (and Tesla for that matter...).

Hey, I'm for anyone wanting to do this, privately funded...

[tcar]

Originally Posted by red-beard

I read the 60 pages. If the temp rises only 40F, the tube system will expand 480 feet over 350 miles.

Don't see why you can't have an airtight expansion/contraction joint at each pylon. There could be 53 (or more) pylons in a mile perhaps.

[RWebb]

Pazzuzu - I suggested maglev as a possibility based on red-beard's saying he doesn't think the air bearings will work.

If they do, then fine. if they don't then you need something else.

[porwolf]

Who wants to travel like this? Looks like being locked in an MRI tube. And those "pods" are supposed to travel at 2 minute intervals. And the general public is supposed to settle down with all their belongings and get ready to exit that quickly? And about the costs: Mr. Musk's estimate of the total land acquisition costs alone is only 1 billion, where as the cost of acquiring lands for the California high speed train is 7 billion! I think Mr. Musks total costs are pure fantasy. The whole concept seems to be a hyper loopy idea!

[porwolf]

Originally Posted by red-beard

Hey, I'm for anyone wanting to do this, privately funded...

Fat chance!