Right, but 15 SUVs 5s apart carry 105 people, and if they can actually travel at an average 150mph, that's faster than the average speed of Skytrain's fastest line by another 3x — so, now we're looking at 315 people moved through the space at the same time.

Factor in cost advantages of the tunnel — 4x cheaper mile-for-mile for the prototype, it seems like? — and the same dollars spent on Boring Co tunnels could actually move a lot more people than Skytrain: you can build 4x the tunnels, moving nearly 1300 people instead of 500.

Even if SUVs can only match the fastest average Skytrain line (50mph), that's still fairly competitive even at the current cost per mile of a Boring Co tunnel. Assuming they can bring cost down further (which is the goal of the company), they could still end up beating trains in terms of people moved per dollar spent.

Listen, I'm not saying it'll happen. But the dismissiveness here reminds me of the "Model 3 will never cost less to build than the price to sell it!!!!!" or "Tesla will never make more than 1000 cars per week!!!" or cash crunch or etc hysteria. I guess Elon attracts that by constantly missing deadlines, but he often still delivers; he just delivers a year or so late.

>15 SUVs, Travelling 150 mph, a second apart

You're fond of throwing in a lot of utterly implausible figures to support your argument here

Despite your pretend block quote, that isn't a direct quote from me (you're taking quotes from someone else in the thread and splicing them into my post, using your made-up version as a strawman). I said 5s apart, which is over 1000ft of spacing — nearly a quarter of a mile, plenty of room for braking — at 150mph; the 15 SUVs is because 75/5 = 15, and we're comparing it to a train system with mandatory minimum 75s gaps.

But 75 cars spaced 1 second apart...

Somehow you assume they will be able to get into that tunnel at these intervals

haha yep.

This plan is like when a city widens a highway but doesn't touch other parts of the road network? What happens? It just moves the choke point somewhere else in the network.

Agreed 1s gaps are too tiny — seems unsafe and that'd be a lot of elevator traffic. 5s seems doable though: assuming 5s gaps, you need an elevator system capable of moving one car every 5s, and then the tunnel is optimally saturated. That doesn't seem insurmountably hard: two elevators that take 10s each to go from surface to tunnel would be enough, along with a bit of on-ramp tunnel to allow cars to accelerate to speed before merging. Throw in a third elevator or a fourth for redundancy while you're at it because elevators are way cheaper than a mile of tunnel, and seems doable.

You're assuming you can get cars into the elevators at 5s intervals.

Almost all assumtions in the discussion start directly in the tunnel, and sometimes at the elevator. Almost no one thinks about: how will cars get into that thing from the road, how the cars will get out of that thing onto the road.

Presumably they'd drive into the elevator on one side, and drive out of the elevator on the other side.

Even if you have a separate elevator for entry and a separate eleveotr for exit: how do you get to a 5s interval?

It's probably just me but I really wouldn't get into anything that was going to be travelling 150mph at 1s intervals. All you need is a tire to go (or something loose on the floor or a dead battery or ...) and you've got not only a huge twisted lump of metal and body parts to untangle, you've almost certainly ruined your tunnel.