The problem with mass transit-- rider appeal, and that it's
Mass, not individualized. If we're going to leave our cars in the driveway they will need to offer a system that is as much like a taxi as possible; on-demand and practically door to door. This IMO is technically feasible. I call it a horizontal elevator.
Small cabs that only hold six passengers or so would be light enough to run on a light overhead track. This opens the possibility of installing track on existing utility and muni rights-of-way, much of which passes the same areas as sidewalks. This opens the possibility of putting endpoints at almost any intersection or in front of any building. Arterial runs could run parallel to a freeway. Track switches would let a cab go off the main run to descending track that reaches ground level at the endpoints without impeding traffic flow. Unused cabs leave traffic areas and seek nearby parking track until called into service. Ridership statistics control where cabs are parked to reduce wait times when summoned.
Cabs obtain power from the track and communicate with a central dispatch and each other for collision avoidance and scheduling. Riders buy a rechargable card that is swiped at any endpoint to summon a cab. For quick departure their account stores the most recent destinations and presents them upon entering the cab, or allows entering a new destination. The passenger is prompted upon entry if they're willing to share the cab (for lower cost) or head immediately to the destination without any stops.
The system would be more or less comparable to a multi-cab elevator (but horizontal) in that a cab is summoned when needed and the nearest empty (or shareable) cab responds. It may stop at selected points but bypasses stops where nobody is waiting. Since it's automated (except for central dispatch) it can be available on a moment's notice 24/7/365.
The system is scalable. Build the track a block at a time or miles at a time. Add or remove cars to satisfy demand. It doesn't burn gallons of fuel driving mostly empty around town like a bus or train that must complete it's circuit whether anyone is on board or not.
As far back as the 70's Alweg, builder of the Disney monorail, proposed something similar but found no interested buyers. Two or three experimental systems that are similar to my description have been built around the country but they only cover a very limited area, such as a University campus, and none have the individual personalized transportation concepts I described. As I recall only one was aerial, the others traveled on the ground, which defeats the purpose of bypassing the bumper-to-bumper gridlock.
As dogma
pointed out, "
...unlike Europe, our culture doesn't have the capacity to change our ways. So any passenger rail system geared towards local citizens is DOA." Large commuter systems that carry a hundred passengers and stop dozens of times along the route have not caught on in our car-centric culture. If it hasn't after this many decades it never will. Since we can't mold the people to the engineer's whim, we need to engineer a system to the people's whim.