The cost of the land is negligible compared to the colossal changes that would have to be made in adapting cars to the system plus whatever mechanisms that would whisk a car onto and off of the rail system. And a glitch in the system with its many cars coming off and going on at designated points would cause accidents with major fatalities.

I appreciate your comments & I'd like to clarify -- cars would not be adapted, people would have to buy new cars. My vision, which could be changed, is to support smaller electrical cars which would be street legal, of course, but cheap and boxy. If you commute in a large city you will appreciate the value of getting to work quickly.

And I agree that the system would have to avoid glitches, it would be ridiculous to think of a "pretty good" program running this.

One question though, when you say the land costs would be negliable compared to adapting cars, could I please check your math? This is some very expensive land, being that this would occur in the most dense urban areas. I am sure I am a bit sensitive in reacting to my first idea here, but I really appreciate your taking the time to respond. Thank you.

It's a problem worthwhile considering but if it is to be built in urban areas it seems to me that public transportation makes more sense financially and engineeringwise. I lived in New York City with the elevated trains in Manhattan and they were an infernal noisy dirty nuisance. Here in Helsinki where I now live the bus and subway systems are clean and efficient and run on a tight schedule so that each stop of the buses has its own timed schedule that can be counted on. It works very well.

The structure could also support dedicated/public vehicles, as long as you can get to the station.

The bus systems I've used have been slow and smelly; and they work best when the customers all live in a concentrated area. For most large cities without existing metro/subways, the freeways are already loud. For distributed/sprawling cities (Los Angeles, etc) buses cannot serve even 1 percent of commutors.

Hopefully, the thrust of my idea would be to minimize financial and engineering issues, as the cost of even adding more lanes to the freeways is astronomical -- let alone new rail systems. Thanks again.

That the public transportation systems you have encountered are dirty and inefficient is more a problem of management than basic incapability. Here in Helsinki the bus systems cover a huge area very economically and on a tight schedule. The subway system is small but clean and also very efficient. Perhaps the condition of the transport systems you see are more a result of the negligent culture of the country as, in general, Finns seem to care about their public facilities and treat them well. As with many of the institutions in the USA there is an atmosphere of contention between the government provided facilities and the public which leads to much destruction and neglect of communal property which can only be detrimental to the general way of life. It is unfortunate that the general atmosphere leads to abrasive government where the relationship is conceived as contentious rather than a genuine attempt to solve mutual problems.

It sounds like Helsinki has little need for a sky-rail system. I think Paris and London and New York may also not need such a thing. Most large US cities, for whatever reasons, have not created successful mass transit systems. Come to think of it, many/most cities with well run public transit systems also have crowded streets & freeways.

More important for an idea is not how many people do NOT need it, but rather how many people DO need it. Its good to feel pride in ones' own people & governement.

Thanks-

This may be of interest to youhttp://media.www.dailyutahchronicle.com/media/storage/paper244/news/2002/08/27/Opinion/The-Sad.Story.Of.The.Demise.Of.Public.Transit-263145.shtml?norewrite200611170121&sourcedomain=www.dailyutahchronicle.com

Yes, I've read about nasty US businesses preventing mass transit from working here. It sounds like there is truth to it. Maybe we can promte my design & then sell out to big oil. :) The American dream...

I had a similar idea, which was to have a narrow, lightweight, one or two lane deck over the highway, and restrict it to the smallest subcompacts. There would be a low speed limit because of the light construction. It would be an incentive for commuters to buy very small cars.