Also, buses don't have the same capacity as rail does—it's difficult to string together 10 buses and still accelerate quickly, navigate turns, and deal with grade crossings with street vehicles (although guided buses maybe can get partway there? [1]). You can feel the burn in the Bay Area if you try riding the lines on Geary or Mission during hot hours.
And the speeds at which buses run within dense metros often cannot compete with modern subway trains—BART, which is an old system already, hits 70 mph and can go faster, which would be kinda scary to do on city streets in a bus.
Not to mention that buses can serve many routes that don't have enough capacity to merit a train, bus routes can be reconfigured without it taking years, and a bus system doesn't cost billions upon billions of dollars to build. Heck, even a single line of a metro system can cost a billion dollars to build.
My favorite is Vancouver skytrain. While building highways they built a train track on pillars. It's fast and usually got me in and out of the city quicker than a car.
I imagine train tracks on pillars cost effective than underground tunnels. For a dense city it makes sense. Not for outskirts.
I get the impression Musk looked at that expense, brought in some subject matter experts, probed them on why that was the case, and decided there must be a better way. From what I've read of tunnel boring, I can see that happening. Not uncommon for a tunnel boring machine to be custom-built and then abandoned in place at the end of the project. A more general-purpose or modular machine might be what he's thinking about. Unexpected geologic formations come up frequently, a function of the expense of manually-intensive sampling processes today. A robotic sampling crawler that bores hundreds of samples, and automatically classifies as it goes instead of sending to an off-site lab, building a 3D map as it moves, might be what he's looking into.
There might be red tape issues even if these technical challenges are overcome, though. Even if you propose going so deep you avoid all other underground infrastructure altogether, government bureaucracies' permitting and related processes will put a floor on the cost avoidance Musk seeks.
While this is true, getting very good at boring underground could be helpful for building underground habitats on mars.
But if you're building a dedicated network in a major city, why on earth would you limit it to buses? Even with a dedicated network, I don't believe buses can be as fast, comfortable or quiet as rail.
I spent a lot of time in Melbourne, Australia and the trams there are fantastic. You can barely hear them when they're operating so they do a lot to decrease noise, they have a ton of standing room and are quite long, so they can carry a lot of people and I don't believe a bus can come close to the comfort of rail.
Even buses are useless during/after disasters in my experience (avoiding legal liability, lack flexibility to mitigate problems, inability to publish changes etc).
Yes, but so do roads. Tunnels especially!
http://i.stuff.co.nz/national/91972268/government-confirms-8...
Highway 7 started as a car-only multi-lane highway. They took a multi-phase approach to building out a light-rail system. The first phase was adding bus rapid transit, increasing fares, and increasing density of new construction. The second phase was adding dedicated bus lanes and light-rail-ready stations. The final phase will be to add tracks and trains on top of the road.
For now. I think that's the whole point of this company. Reduce cost and risk of drilling just like SpaceX's goal is to reduce cost and risk of space flight.
I also get a feeling he's read "foundation" from Isaac Asimov which talks about this.
[1] http://www.sheepletv.com/nuclear-tunnel-boring-machines-swit... [2] https://en.wikipedia.org/wiki/Subterrene
My impression is the boring feasibility and costs will not be the limiter of a very cool tech like this happening, but a more boring practical cost, probably the "zoning" cost required to get compliance and permission for all that state and federal land needed to build the underground link network.
I'm not convinced that the video you linked on sheepletv above the "underground alien bases" one is the most reliable info.
Finally, from my point of view, getting your ridicule feedback hurts because my aim is to contribute to substantive discussion here, and I don't want to feel discouraged from posting something substantive because it might also have info that could be cherrypicked for ridicule, then letting me feel like I wasted my effort contributing because the info was later unfairly presented. I don't want to feel like I have to do extra work "defending" the original effort to contribute, against such ridicule. So, please, before you rush to ridicule something, really take a look to see if there is substantive content there, and refrain from misrepresenting it, thanks.
* Several videos about Pizzagate (and I don't mean critical examinations, either)
* A number of anti-Semitic images ("Jews control the banks", etc)
* A video literally titled "Hitler Survived WWII & Occult Nazi Scientists Developed VRIL Haunebu Foo-Craft (UFO’s) at Secret Antarctic Base-211"
* Another video literally titled "Illuminati Hip Hop Blood Sacrifices Exposed"
* A video about how Christmas is a "Satanic Illuminati Holiday"
* And this video
It's not a great stretch to say that their description of a "nuclear tunnel boring machine" is every bit as absurd and untrue as the other videos they distribute.
I linked to that page and specified NTBM. You could have substantially commented on the Los Alamos patents and their discussion on that page. But you chose to go off that page and to emphasize easy-to-ridicule parts. Please don't do that, thank you.
It might be a logical error, but it's not a mistake. If someone tells you lie after lie after lie, and then says something new, whose truth you can't immediately evaluate, the sensible thing to do is to think: this is also probably a lie.
It just didn't work as a strategy if you actually wanted the find the truth. That's one thing this is about here.
The other thing I think you missed was the emotional context of these comments. I'm clearly asking for support and help to make HN welcoming, by not misrepresenting or cherry picking easy-to-ridicule info. It hurts when they do that and I don't like it. Please don't do it, don't ignore the people behind the comments, and don't quote this
> You just did the thing I suggested was insubstantial and said hurts and I didn't like. Please stop.
pretending that you've contradicted this, and made it somehow okay. You haven't and it's not.
At the moment boring machines do not work like that, a conveyor belt of small pieces comes out. What if A380 fuselage sized pieces of rock came out instead and were conveyed off to the coast for coastal defence purposes, or even land reclamation? Carrying objects weighing thousands of tonnes to the sea is not simple but the amount of material excavated the hard way - ground to pieces first - would be significantly lower.
Maybe they have a 'coring machine' rather than a 'boring machine'?
Fundamentally, this is about short-circuiting the regular road network and establishing a managed packet network that can bypass congestion. Interestingly, that's also the value proposition of public transit, though it also runs into issues of cost, and too low of a population density make it unfeasible.
I still think we haven't fully leveraged the potential of busses. In most cities, they are slow because they combine the disadvantages of road traffic with the disadvantage of time tables. But what if busses operated on their own dedicated network? Bogota deployed a public transit system made with busses but with a UX of a train[1]. This is a genius idea that could work in many US cities, which have a lot more space to spare.
But back to the original idea, I think we might see in the future a "managed" road network, reserved to self-driving cars which are driven by some central management system, optimising routing for the whole network so as to prevent congestion. This won't require tunnels, just gates, dedicated roads and lots of software.
[1] https://www.youtube.com/watch?v=cU6ImWY4IBc