The End of Traffic Jams: A Transportation System for the Future

By Francis D. Reynolds

February 2001

Originally published in the September-October, 2001, issue of The Futurist magazine, pp 44-51. Posted with permission from the World Future Society, 7910 Woodmont Avenue, Suite 450, Bethesda, MD 20814. Phone 301-656-8274; fax 301-951-0394

In the future we will use still more private cars, yet we will avoid most of the transportation problems we now have—by using our cars in two distinct modes. The cars may be standard or specialized, depending upon the details of the system. They will be driven in the normal manner on the streets, and they will travel automatically on high-speed dedicated guideways—but their drivers won't be driving. Trips of more than several miles will be on these guideways rather than on the highways. A dualmode system will be even more "personal" than "Personal Rapid Transit," since we will be using our own cars. And it will also be more "rapid," than PRT since we won't have to walk to and from stations. We will travel from door to door as we now do, without getting out of our cars, but we will travel safer, faster, cheaper, with less stress, and with neither gasoline nor pollution.

"Automated Highway Systems" (AHS) would likewise include both manually-driven and automatic modes, but the term "dualmode" has come to mean a system that incorporates special automatic guideways with most of the artificial intelligence in the guideway network as opposed to putting it in the cars. Automated Highway Systems would use our existing automobiles and dedicated lanes of our existing highways, with high-tech additions to both.

This "use-what-we-have" goal seemed like a good idea at the time but it would be penny-wise and pound-foolish. AHS would not solve our energy problems or reduce our global warming problem, and it would do relatively little to relieve traffic congestion. Its safety record would probably be worse than that of ordinary highways, and much worse than dualmode, because of the large number of safety-critical elements AHS must use in series. The US Department of Transportation withdrew its support of AHS in 1998. See a comparison between AHS and Dualmode Transportation.


Our national (and international) dualmode system will be as much of a universal cure as we are apt to find. Surprisingly, it will solve not just a few but most of our transportation and transportation-related environmental problems in one fell swoop. And some of the things that dualmode transportation will do for us can't be done any other way. It will have many advantages over conventional automobiles and highways, over transit systems and trains, and it will even eliminate much of our present air traffic.

Dualmode will reduce highway traffic to a dribble—by getting most of the cars onto the guideways instead. A less obvious advantage is that it will also reduce the jams on urban streets. This will come about because a high percentage of guideway cars going to the cities will not exit to the downtown streets at all. These cars will be automatically parked directly from the guideways. (Valet parking with no one to tip.) So not only will street traffic be reduced but also street-parking problems will be alleviated.

Since mass-produced automobiles became available the percentage of travel by transit and by railroad has steadily decreased, and government pressures aren't going to reverse that century-long trend significantly. Dualmode transportation is the only answer that will really work. It is the answer because it combines the best aspects of both private transportation and public transportation, and of highways, trains, and airlines, as we will discuss; yet it reduces or eliminates most of their shortcomings.


reygraphic1.jpg (101881 bytes)

The guideways will carry almost all of the categories of vehicles now used on streets and highways. Most of the traffic will consist of private cars, but there will also be transit buses, Greyhound-type intercity buses, rental cars, taxis, school buses, delivery trucks, cross-county freight traffic, and possibly personal-rapid-transit vehicles. It is expected that a high percentage of the dualmode private cars for commuting will be small, perhaps two-passenger. Small cars tend to be more dangerous on the highways, where they have to compete with heavier cars and trucks. Size won't affect safety on the guideways because there all vehicles will always travel at identical speed, "slick roads" won't be a problem, and the automatic system will always "see" perfectly in any kind of weather.

Most of the vehicles will be dualmode—used both on the streets and on the guideways— but the cross-country buses and the long-distance freight vehicles will be single mode, operating only on the guideways—with no drivers. The driverless freight vehicles will be more like autonomous cargo containers than like trucks.


The guideways will operate nonstop at full speed day and night, just as our highways should if they weren't jammed. I suggest a constant system speed of 60-mph in and around cities and a constant 200-MPH on the guideways between cities. The cars will be synchronized and may travel only one foot apart.

These kinds of velocity and headway numbers provide enormous system capacity. At 60 mph a single guideway lane would carry the traffic of twelve highway lanes, and at 200 mph one guideway lane would be equivalent to forty highway lanes. Need for more lanes will become a thing of the past. And we note that the one lane of guideway will cost far less than twelve or forty lanes of highway.


Domestic airline traffic will be greatly reduced by our dualmode transportation system. When we include reservations, the trips to and from the airports, parking, cancelled flights, late flights, baggage checking, security checking and all the rest, the 200-mph guideways will be faster than flying for trips up to perhaps a thousand miles. And guideway travelers will have privacy instead of someone else's crying kids. They will also have their own cars to use at their destinations instead of airport buses, rental cars, or taxis. And airfreight traffic will be greatly reduced by driverless freight containers on the high-speed guideways.

And there is another, perhaps more important, reason for retiring as many airplanes as we can. Unless we have unexpected breakthroughs (like electric airplanes using long extension cords) flying is going to become very expensive when our petroleum is almost gone.


reygraphic3.jpg (88345 bytes)

If we wish to enter the guideway system we will drive into an "entry stop," shut off the motor, and punch the number of the desired guideway exit into a keypad on the dashboard. That exit number will tell the navigation computer where to send us, and tell the billing computer how much to charge us for that trip.

Meanwhile electronics in the entry stop will be reading a chip in the car that identifies the car and provides other vital statistics. At the same time an automatic system will check the operation of all parts that are essential to safe travel on the guideways. If a vehicle fails to pass any of these requirements it will be denied access to the guideways and must return to the streets.


reygraphic2.jpg (101887 bytes)

After these preliminaries, which may take 30 seconds, the vehicle will be accelerated to guideway speed, and merged with the guideway traffic. "Switching" actions will be initiated automatically in the vehicles, not by switching the tracks as is done on railroads. The cars will switch from one guideway to another at full speed, the same as we merge with and leave freeways at full speed. The dualmode guideway system will have much more in common with our highway system than it will with the railroads.


Dualmode cars will be battery-electric or fuel-cell powered for street use. But since these cars will be on the guideways using guideway power for most of their travel, batteries or hydrogen tanks that are now inadequate for highway use will be more than adequate for dualmode in its limited street use. However, in the early years of the system, internal combustion engines may be used in the street mode, since these early cars will need to use the highways where guideways are not yet available.


The amount of AC power required for the guideways will far exceed any excess capacity of our present power grid. The additional power needed can't be made from petroleum or natural gas, because the readily accessible deposits of both of these will be mostly gone by the beginning of the Dualmode Transportation Era. We have plenty of coal, and it is now used to generate half of the electricity in the United States but to say the least, it doesn't work well in internal combustion engines. And coal is far from green.

However, even if we have to burn more coal to push additional electrons through the transmission lines, the overall dualmode system will be roughly twice as efficient as automobiles. So transportation will burn less fuel and therefore generate less carbon dioxide than it now does. It is important to note that we can make electricity for the guideways from any energy source, while internal combustion engines demand fuels that are environmentally bad and in short supply. Please don't believe that biomass alcohol will provide all of the fuel we need when our oil is gone. Biomass fuel is labor intensive, and there isn't enough arable land to grow it on—unless we stop eating.

In the future the percentage of electric power from wind turbines and solar arrays will increase, and maybe there will be nuclear fusion. We have many options in generating electricity; with internal-combustion automobiles we have very few.


The different dualmode system inventors have proposed different details. In some systems "true dualmode cars" would be equipped to run on the guideways directly, and in other systems there would be interfacing pallets between conventional cars and the guideway.

Dualmode systems have been proposed where conventional rubber tires on both the guideways and on the streets would support the cars. In others the cars would ride rail-type guideways on added steel wheels. Air-bearing technology (related to hovercraft) is also a possibility for the support of the vehicles on the guideways. And many dualmode system inventors propose maglev guideways.


Maglev trains are quite well developed, especially in Japan and Germany. They are very fast, quiet, and safe; but trains are obsolete whether they are supported by steel wheels on rails or by maglev. For that reason maglev trains will die in their infancy. The concept of magnetic levitation per se however, has interesting advantages for dualmode systems, where the cars are not coupled into trains. Some of the advantages of maglev are obvious: If the cars are floating with their street motors off they won't be wearing out. And neither will the guideways wear, so they won't develop faulty rails or potholes.


Linear electric motors are now used to propel maglev vehicles, roller coasters, aircraft carrier catapults, and are being studied for space-vehicle launchers. Linear motors are like ordinary AC motors except that they are laid out flat and the working parts move linearly instead of rotating. A continuous "stator" is built into the guideway, and the moving parts of the motors are rigidly attached to the levitated cars. The AC armature windings can be either in the cars or in the guideway, with the field magnets in the opposite location. The efficiency of linear motors is many times higher than that of internal combustion engines.


Linear synchronous motors will be used in the guideways. This type of linear electric motor will keep all of the cars running at precisely the same speed at all times. Therefore the spacing between cars will never change. It will be virtually impossible for them to collide with each other. They will be like boxes on a conveyor belt--or like plug-in electric clocks that all keep exactly the same time because they are all running synchronously on the same alternating current. In a dualmode system synchronous propulsion will eliminate a large number of proximity sensors and velocity-control systems that would otherwise be needed, thereby greatly simplifying the system, reducing its cost, and increasing its reliability and safety.

Absolute synchronization of all of the cars on the guideways is essential to a safe high-speed high-capacity standardized national guideway system. That statement applies whether the vehicles are dualmode, single mode, or a combination of both (which they surely will be).

However, at this time the recognition that we must have a dualmode system and must start planning for it is much more important than premature concentration on the engineering details. Later we will attempt to optimize the balance between the many requirements, including high capacity, safety, speed, utility, long life, acceptability to the public, environmental factors, fossil fuel depletion, overall energy consumption, cost of the guideways, and cost of the vehicles. There are several different approaches to achieving most of these requirements, and time will tell which combination wins out.


There will be an interim period when only part of the dualmode guideways are complete, and only a few people will have yet purchased the new nonpolluting dualmode cars. In order to make the available guideways useful to all during this interim period, existing automobiles will be driven onto pallets designed to run on the guideways. Even after most people have true dualmode cars, and after most of the guideways are complete, some pallets will still be used to accommodate not only a few automobiles, but also boats and other trailer loads.


Private cars are considered bad these days, and so is urban sprawl. But when we examine the basics we find that neither cars nor sprawl are inherently bad. The things that make both of them seem bad are pollution, fuel depletion, the increasing area of land covered with concrete, and traffic congestion. But these bad byproducts of cars and sprawl will be eliminated by a dualmode system. Both urban sprawl and private cars are basically wonderful, because they contribute to fulfilling life styles.


We can't simply continue patching the obsolete transportation systems we now have. The patches are obviously not working, because the situation keeps getting worse rather than better. More and more people see that none of the conventional things being proposed will do much good. Trains and automobiles are over a hundred years old; they were nineteenth-century inventions. They are obsolete. The only way to get high capacity and safe high speeds, keep the wonderful advantages of private cars, and also solve most of our transportation-related environmental problems is to design and build a revolutionary system for 21st century traffic and life styles using 21st century technology. We will, because there is no other satisfactory choice.


In democracies "Thou shalt not drive" commandments are unacceptable. Since people won't give up their cars, and more people are getting cars, it doesn't help measurably to build more transit or new kinds of transit. Twenty-five years ago transit accounted for five percent of urban travel. Now, with car use almost universal, transit averages perhaps two percent. Earlier urban transit systems were financially profitable because there was a huge market for their services, but now subsidies pay most transit costs.


The bankrupt US passenger railroads were taken over by the government in 1971. The Amtrak deficit has continued to increase ever since. Yet we still build more trains in attempts to alleviate our traffic problems. Harvard University recently released a comprehensive study that analyzed the performance of more than a dozen light rail systems built in the United States in the last twenty years. None of them were financially successful, and none of them even came close to achieving the riderships they had promised. Worst of all, there were very few light rail riders that were new transit riders. Three quarters of the customers were former bus riders, and many of the bus companies then went out of business. None of these expensive light-rail systems had any measurable effect upon the traffic congestion. Don't those who still propose more "light" or conventional rail systems read?

We must and will have plenty of transit service to serve legitimate transit needs, but with some differences. Those who propose extensive single-mode transit systems are looking at the future much too narrowly and unrealistically. The single-mode transit people should join the dualmode movement, because on the universal guideways transit service will be much more available and much cheaper. The transit systems themselves will be dualmode, with the transit vehicles exiting and reentering the guideways locally to serve neighborhoods without guideways.

Private cars and freight will be paying the lions share of the guideway costs. Transit's share will be very small. On a single-mode light-rail system the transit organization has to pay for the whole thing. Expanding the bus service is always cheaper than building a dedicated light-rail line. But rail lines breaks free of the highway and street congestion and can therefore offer faster service than buses on long runs.

When we have the dualmode system, transit will eat its cake and have it too. Because of the huge capacity, high speed, and offline acceleration and deceleration, the guideways will provide the same advantages to transit as light rail does. Yet using the guideways will be many times cheaper for the transit companies than building their own dedicated rail systems. Further, to get a system approved and built, they won't have to fight all the political and legal battles alone. Transit will be a minority user of the guideways, just as they are of the streets and highways—but no traffic congestion.


You want to know how much our huge national dualmode system will cost. How the heck should I know? Twenty to fifty million dollars per mile of guideway. Hundreds of billions for the huge nationwide system. But note that unlike trains the vehicles will not belong to the guideway company, so they won't be part of the system cost any more than the cost of the cars on our highways are considered part of the cost of the highway system. The guideway system will be paid for by automatically charging every vehicle that uses it (and essentially all vehicles will use it.) What will the guideway use fees be? Far less than the cost of gasoline-powered transportation will be by then.

Government "Guideway Bonds" should finance the design and construction. These, like WW II "War Bonds" will sell because bond buyers will be making not only a financial investment but also an investment in their own future way of life. Guideway Bonds will be secure, because the market for guideway use will be enormous and growing.

The total system will be very expensive, but the transportation it provides will be inexpensive. Guideway use will sell itself. Commuters stuck on the highways who see the adjacent guideway traffic flowing at a constant high speed will surely start using the guideways. Bear in mind that it will be a universally used system, like our highways are. Conventional rail transit systems being built now will serve relatively few people. But a dualmode system, with somewhat comparable costs per mile of guideway, will accommodate all of the private cars, buses, and freight and make a profit.

Subsidized low-cost transit passes will probably be made available to the economically challenged, but we will no longer subsidize transit for those who can afford it. We will no longer need to bribe people to leave their cars at home, because there will be plenty of space on the guideways and the dualmode cars won't be using the last dregs of the world's petroleum reserves or polluting the atmosphere.


With dualmode transportation things won't come to a halt when the world's petroleum is gone—and that will be very soon. The climbing price of gasoline speaks for itself; and it is going to climb ever more steeply until the world's reserves are gone. With only existing types of transportation, or with Automated Highway Systems, we could experience a repeat of the dark ages. Literally dark in some places, since much of our electricity comes from petroleum and natural gas (which is also being rapidly depleted). Make that the coming dark and cold ages—Most of our domestic heat comes from oil and gas too. I would prefer to keep the heat and the lights on a little longer by not continuing to use petroleum or natural gas for transportation.


The dualmode transportation concept has been separately invented by over two dozen people that we know of. When a number of people independently think of the same solution to an urgent problem at roughly the same time it is a good indication that the need is real, that the proposed solution is probably the right one, and that it is time to implement that solution. See how dualmode will solve or reduce many of our existing transportation problems.

Recently I heard a supposedly responsible leading transportation engineer say, "Dualmode systems are something that we should keep in mind for the future, but it is too early to think about such revolutionary ideas." Good Lord! Doesn't he realize that it will take at least a couple of decades to design and implement such a system? By that time most of our oil will be gone, global warming will be worse, the air in some cities will be too thick to breathe, and I don't even want to think about the traffic jams by then. We should have started designing and implementing a dualmode system twenty or thirty years ago!


Some time ago I contacted a senior and highly respected Ph.D. in the Volpe branch of the US Department of Transportation (who asked not to be identified), on our need for a dualmode system. Let me quote a bit from his response.

"It is by no means clear that any entity exists with the authority to design and implement a true 'national' system, nor that agreement on its nature could ever be reached. Dualmode is a very different notion than the Interstate Highway System. It is hard to imagine the process by which a decision could be reached among the many necessary parties to commit to such a major and expensive undertaking. It is hard enough to simply widen a major highway. The mind boggles at just the time and cost of the environmental impact statements. I simply do not think that the right of way and environmental approvals for such a network could be obtained even if the funding were available."

His implication is that there can be no more revolutions in transportation—that we can't get there from here. Yes, things have certainly changed since the United States built a railroad system, a highway system, and our airports and airways network. The impediments my correspondent mentions are real, major, and will be very difficult to overcome. But impossible? No—we can't accept that conclusion. There must and will be another revolution in transportation—the dualmode revolution.

There is an old proverb that says, "Those who say it can't be done shouldn't stand in the way of those who are doing it." Unfortunately we are not building a dualmode system yet, but we should be. We must listen and learn from the doubters, but not blindly subscribe to all of their pessimism. There have been doubters during every innovative revolution in history. It has been said, "The difficult we can do immediately, the impossible takes a little longer." If that is the case let us define the acquisition of our dualmode system as "difficult," because as a mobile society we don't have much "longer."

If a patient dies when there is no cure, that is sad but understandable. If there is a good cure but the patient dies because the cure wasn't used, that is irresponsible, frustrating, and criminal. I am urging the use of the dualmode cure, because the patient's—the world's—many transportation, energy, and environmental illnesses are close to terminal.


The politicians will be in favor of building a dualmode system only when they can see that supporting it will win them votes; the automobile companies will support it when they can see a market for millions of dualmode cars; the unions will support it when they foresee the hundreds of thousands of jobs that will be created; and the media will publish it only after it becomes "news." Because of these and many other impediments to getting dualmode, it won't just happen. The general public and our leaders must first learn of the concept and then demand that such a system be designed and built.

If you agree with these arguments for building a dualmode transportation system please do all you can to help. Write letters to the editors, argue with your boss, alert your representatives and transportation officials; become a common sense dualmode transportation activist. Grass roots efforts can pay off, but remember that it takes a huge number of grass roots to grow a lawn. Some type of dualmode system is inevitable, but the vital question is, how soon can we have it? How long will we delay the decisions and further compound our huge problems?


I gratefully acknowledge that many of the ideas expressed in this article came from other inventors and promoters of dualmode systems. The Appendix contains a partial list of other workers and contributors in this field, but specific credits are impossible since most new dualmode ideas rapidly enter the public domain via the Internet, and their origin is forgotten.

Special thanks to Tom Chalkley who prepared the illustrations. His website is

The author also acknowledges that he has written somewhat similar technical papers and/or made presentations on dualmode transportation for The Society of Automotive Engineers, The Intelligent Transportation Society of America, The 2000 FISITA World Automotive Congress, The Institute of Transportation Engineers, The Transportation 2000 Conference (US Department of Energy), New Visions in Transportation Conference (Aspen 2000), The Intelligent Transportation Systems Magazine of the IEEE, to the AIAA, for The Economist, and others.


Francis D. Reynolds, P.E., is a corporate and private engineer and technical inventor who holds a number of patents. One of his inventions, on remote control, was vital to a national defense missile. He has lectured nationally, including at NASA Goddard. For years he was a guest lecturer at the School of Engineering at Seattle University, and taught evening courses on inventing at the University of Washington. He serves as an invention evaluator for the Innovation Assessment Center of Washington State University.

Previously he held Engineering Management positions on many Boeing programs. His private engineering efforts have included unique dynamic-hydrofoil vehicles, hovercraft, advanced ornithopter design and development, robotics, and remote control systems. He has had over a hundred articles published in journals and magazines. His book, "Crackpot or Genius? A Complete Guide to the Uncommon Art of Inventing" was published in 1993, and reprinted in hardcover by Barnes and Noble in 1999. He now has a book on dualmode transportation ready for publication.

Francis Reynolds has a BS degree in Mechanical Engineering from the University of Washington, and is a Registered Professional Engineer. He is an Associate Fellow of the American Institute of Aeronautics and Astronautics, and a member of the Flight Research Institute. Francis will welcome correspondence on dualmode topics at


The following material is mostly from the huge and excellent Innovative Transportation Technology Web site established and maintained as a public service by Professor Emeritus Jerry B. Schneider of the Departments of Urban Planning and Civil Engineering at the University of Washington in Seattle. Please see: and: This latter site is an ongoing dualmode debate page where a number of us are working toward agreements on the details of an optimum dualmode system.

Proposed Dualmode Systems, by Name

Autoshuttle - a German concept that would utilize maglev technology to transport a variety of conventional vehicles in carriers at high speed (Krevel and Steingroever)

AVT-Train - an auto ferry concept being developed in California

Autran - a system with carriers that would carry autos, passenger cabins and freight containers (Van Metre Lund)

Bee Hive - a concept system developed in a dualmode design exercise at the Urban Lab

Biway - (England) is similar in some ways to HiLoMag, RUF, and Flexitrain (Jim Buick)

Bladerunner - a large truck capable of rail or highway operation that can carry vehicles, under development in the U.K.

BT - a dualmode concept designed in Korea for high capcity operation in dense city areas, includes some interesting animations of dualmode operations

Carbus/PMT - uses large trucks on the freeway to carry conventional or small electric vehicles as well as bicycles and people (Dave Petrie and Andrew Frank). A similar concept has been developed called Autobus (Bill Bowen)

Electronic Guideway System (EGS) - a small vehicle concept that the inventor refers to as a "quadmode" system

Electric Energy Line System (EELS) - a dualmode concept that has been derived from a holistic engineering study

Flexitrain - small, public, rental or privately owned electric cars that can be connected into trains for longer trips, being developed in New Zealand (Charl du Toit)

Higherway Transit Research - a suspended, dualmode PRT (Tad Winiecki)

HiLoMag - personal cars, light trucks, transit, long-range buses, taxis, etc. on streets and national high-speed synchronous automated guideways. (Francis Reynolds)

IMT (Individual Mass Transit) - a concept that is still pretty vague in terms of technology - but the concept description is good

InTranSys (Integrated Transportation System) - a "skyhook" concept. A variety of vehicles could be carried on suspended pallets, using a linear synchronous motor for propulsion. Cimarron Inc. (Richard Guadagno)

Japanese automated freight system - uses an automated guideway for long trips (no drivers) and conventional streets for final delivery (or pickup) - an Automated Freight application

MegaRail Transportation Systems, Inc. - a dualmode system that uses "carriers" to transport passenger or freight vehicles that is under development in Fort Worth, Texas. It has also been designed to accommodate vehicles that can operate on the guideway without a pallet. (Kirston Henderson) Also see MicroRail for a smaller version.

MIX - a small vehicle designed for neighborhood use that can also be suspended from a cable for longer faster trips.

Monomobile - a dualmode, suspended small vehicle system being developed in Cincinnati, Ohio (Jay Andress)

NAP (National Automated Pallet system) - A proposal for a national dualmode system by Walt Velona

RUF - a Danish dualmode concept that uses electric vehicles on conventional streets and a monorail-like automated guideway for longer, higher speed trips under full system control (Palle Jensen)

Segway - uses Smart Carts (pallets) on an automated guideway to carry a variety of vehicles. (Marty Bernard)

Skybikes and Skytrains - describes a concept that combines bicycle and PRT concepts to create a dualmode, high capacity peoplemover.

Station cars - there are French, Japanese and American efforts to devise some dualmode capabilities under this heading

Synchro-Rail - a dualmode concept that uses small electric cars propelled by linear synchronous motors, being developed in the U.K.

Transglide 2000(TM) - describes a bicycle transit concept that would utilize elevated, bike-only guideways.

Transmodal Capsule - a master's thesis done at the University of Washington in Seattle very conceptual but has stimulated a lot of interest.

TriTrack - a dualmode concept that features low cost guideways and high speed vehicles for 1-2 persons, being developed in Austin, Texas.

home2.gif (1492 bytes)

Last modified: December 27, 2004