151–155 of 155 posts
Earlier quoted context omitted.
The limit on speed is air resistance.
Let's walk before we run. Getting Shinkasen-style trains in the USA should be step 1.
Earlier quoted context omitted.
> That's an absurd comparison. The actual tunnel was build far faster. So was the Channel tunnel. It takes quite a bit of time after physically digging the tunnel until you can actually open it to the public. > And if its so amazingly expensive as you claim, why was the only commercial competitor 2x as expensive? Perhaps because other tunnels left space for potentially saving someone from the tunnel in case of an eme…
> So was the Channel tunnel. It takes quite a bit of time after physically digging the tunnel until you can actually open it to the public. Then you are not comparing tunnel boring machines anymore. And even so, its a totally different type of project on a totally different type of scale with totally different classes of machines. > Perhaps because other tunnels left space for potentially saving someone from the tunn…
https://eur-lex.europa.eu/legal-content/EN/TXT/PDF/?uri=CELE..., Annex I, 2.3.6:
In any event, in new tunnels, emergency exits shall be provided where the traffic volume is higher than 2,000 vehicles per lane.
1.3.1:
Where ‘traffic volume’ is mentioned in this Annex, it refers to the annual average daily traffic through a tunnel per lane. For the purpose of determining the traffic volume, each motor vehicle shall be counted as one unit.
https://www.teslarati.com/elon-musk-boring-co-lvcc-loop-capa...:
the LVCC Loop did meet its capacity goal of 4,400 conference attendees per hour during a demonstration event in May
2.3.8:
Where emergency exits are provided, the distance between two emergency exits shall not exceed 500 metres.
https://en.wikipedia.org/wiki/The_Boring_Company#Convention_...:
Boring of the first tunnel, 4,475 feet (1,364 m) long
⇒ if that tunnel had been built in the EU, I think it would have needed emergency exits.
(Searched for US regulations, too, without success. I expect them to be less stringent)
Now it sounds like a doomed idea, basically just pneumatic tubes at a larger scale, but I remember how fresh it sounded a few years back.
The crazy thing is the idea of small pod electric trains is still possible. Look at americas 99% idle railroad tracks.
Earlier quoted context omitted.
> Vacuum travel in a a tube does actually make sense. It may not be viable (yet?) but the idea is sound. I'm not sure the idea will be viable, ever. Too many problems, not enough rewards. For example, the problem of a vacuum tube developing a leak. The leak would start an implosion, which then propagates down both directions of the tube at mach-1 speed of sound. The implosion would resemble the continuous crushing of…
> The leak would start an implosion This is a science fiction trope with no basis in reality. The pressure differential is one atmosphere to zero atmospheres which is functionally equivalent to one atmosphere to two atmospheres or what you get from diving 10 meters into the ocean. The Apollo LEM had a shell that was pretty equivalent to aluminum foil in places. One atmosphere to zero atmospheres is the sort of thing…
You're not entirely wrong however. There is effectively one atmosphere differential at sea level, but framing the difference that way is at worst intellectual dishonest, or at best a rather naive understanding. In actual reality there is a very long tube, and all the surface area is under pressure. In metric is 10,000 kg per square meter, multiplied by all the square meters down the length of tube. Of course this simplified understanding ignores the weight of the transport capsule inside, which causes a momentary higher differential. And, the hyperloop won't work at sea level, as others have pointed out, it would have to be underground to avoid thermal expansion issues... meaning higher pressure.