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I think Musks main idea is that everyone else is drilling tunnels with larger diameter than necessary and that drilling scales badly with tunnel diameter. Also

I think Musks main idea is that everyone else is drilling tunnels with larger diameter than necessary and that drilling scales badly with tunnel diameter. Also he probably thinks that SpaceX material tech and brunt force can make it faster.

dx034 8y ago
And no one before thought of that? The reason tunnels have become larger over past decades is because of additional requirements (safety, electricity, larger rolling stock). That small tunnels are easier and faster is known at least since the 1890 when much of the London underground (deep underground, not cut and cover) was built.
- masklinn 8y ago
  And as anyone who's been in the London underground and is more than 5ft tall can attest, it's also very uncomfortable. Only place where I had to bend to enter and exit a subway car, only place were I could comfortably stand was the center alley, and I'm hardly tall.
  - spacenick88 8y ago
    That's why the Boring company vehicles are more like cars and you'd enter them while on the surface from which they'd use an elevator to get underground. Also they wouldn't block the rail while waiting at a station. Subways are pretty efficient systems but that doesn't mean they are anywhere close to the most efficient system, especially considering they were invented during a time where it would be unthinkable to dynamically compute optimized schedules. When the London underground was built you'd need a room full of people working many hours to come up with a workable scheduling.
    - jcranmer 8y ago
      > Subways are pretty efficient systems but that doesn't mean they are anywhere close to the most efficient system, especially considering they were invented during a time where it would be unthinkable to dynamically compute optimized schedules. Personal rapid transit systems, which is basically what Loop is and sounds like what you're proposing, have been proposed several times and even built in a few places (Morgantown's is perhaps the most notable, at least in the US). They just haven't shown themselves to be very capable. Subways are probably the most efficient system possible. They're a 1-D system, with transfers between separate 1-D system. When there's no conflicts between different lines (i.e., everything is grade-separated), you can dedicate most of the space to the actual trains themselves and the safety buffers for moving trains to stop. As you move to more complex systems, now you need to have extra gaps that other trains on other lines can merge into, which reduces scheduling flexibility. In other words, subways are much simpler, and it turns that simple systems are often the most efficient in practice. (If you want to see an example of what can go wrong even with computerized scheduling of dynamic routing, look at Denver's baggage system).
- spacenick88 8y ago
  I don't know about thinking. A lot of people thought about landing orbital rocket stages, during the last 70 years of rocket technology. Yet it's only been done by SpaceX a startup everyone laughed at with the argument that obviously the existing players would have done it if it were feasible.

dx034 8y ago

And no one before thought of that? The reason tunnels have become larger over past decades is because of additional requirements (safety, electricity, larger rolling stock). That small tunnels are easier and faster is known at least since the 1890 when much of the London underground (deep underground, not cut and cover) was built.

masklinn 8y ago
And as anyone who's been in the London underground and is more than 5ft tall can attest, it's also very uncomfortable. Only place where I had to bend to enter and exit a subway car, only place were I could comfortably stand was the center alley, and I'm hardly tall.
- spacenick88 8y ago
  That's why the Boring company vehicles are more like cars and you'd enter them while on the surface from which they'd use an elevator to get underground. Also they wouldn't block the rail while waiting at a station. Subways are pretty efficient systems but that doesn't mean they are anywhere close to the most efficient system, especially considering they were invented during a time where it would be unthinkable to dynamically compute optimized schedules. When the London underground was built you'd need a room full of people working many hours to come up with a workable scheduling.
  - jcranmer 8y ago
    > Subways are pretty efficient systems but that doesn't mean they are anywhere close to the most efficient system, especially considering they were invented during a time where it would be unthinkable to dynamically compute optimized schedules. Personal rapid transit systems, which is basically what Loop is and sounds like what you're proposing, have been proposed several times and even built in a few places (Morgantown's is perhaps the most notable, at least in the US). They just haven't shown themselves to be very capable. Subways are probably the most efficient system possible. They're a 1-D system, with transfers between separate 1-D system. When there's no conflicts between different lines (i.e., everything is grade-separated), you can dedicate most of the space to the actual trains themselves and the safety buffers for moving trains to stop. As you move to more complex systems, now you need to have extra gaps that other trains on other lines can merge into, which reduces scheduling flexibility. In other words, subways are much simpler, and it turns that simple systems are often the most efficient in practice. (If you want to see an example of what can go wrong even with computerized scheduling of dynamic routing, look at Denver's baggage system).
spacenick88 8y ago
I don't know about thinking. A lot of people thought about landing orbital rocket stages, during the last 70 years of rocket technology. Yet it's only been done by SpaceX a startup everyone laughed at with the argument that obviously the existing players would have done it if it were feasible.