[ardecila]

^ Okay... the public investment here is literally zero, apart from what Daley already sunk into the Block 37 facility. Why not let Musk try? All the risk is on him.

As for feasibility... what Musk is proposing is essentially Deep Tunnel but with even smaller tunnels, so it's nothing that hasn't been done before. It sounds like this is a "dumb tunnel, smart vehicle" system so the concrete tunnel is pretty much all that needs to be built, plus the two station pits and a handful of ventilation structures along the route for smoke exhaust and emergency exits. There are no tracks, no signaling systems and no traction power. I assume safety concerns will be addressed with a wifi repeater system in the tubes or some such that shuts the entire system down if one vehicle reports a malfunction.

I mean, this honestly doesn't sound any different than the various "new" transit systems that were built over the last century, from Disney's monorail to rubber-tired metros to airport people movers. The only flaw, IMO, is the same flaw that those other systems shared: low capacity. That made them poor replacements for a true subway system. Musk's O'Hare Express, with tiny 16-passenger vehicles and a $25 fare, is wildly impractical for MASS transit. But for a niche market like serving business travelers between O'Hare and the Loop, it might be perfect. Just don't believe the rhetoric that this is the "future of transit".