I Am Not Unfriendly to Dual Mode

by D.S. Gow


August 5, 2002.   Francis Reynold's grand vision of a dual mode future is a good one, I have never said it was not. He is nothing if not a dedicated, fervent advocate for the concept, and I have nothing but respect for the work he has done.

The title of my original Dual Mode piece contained the word "misgivings". I chose it carefully, as it conveys the intensity of my skepticism as well as my familiarity with the literature: the former is mild, and I have read a lot of dual mode material but of course nowhere near the entire body of work. Any problems I see in dual mode's current technical status are just that-- technical. I never said I thought current dual mode weaknesses or vagaries were insoluble, I merely was highlighting problems I saw with one or more designs which I feel render dual mode in the main a still-immature technology. Just as with criticism of PRT, I believe that most dual mode "flaws" touted by critics are merely design issues that can be remedied with good engineering. And, as I indicated previously, I have no problem with creating PRT networks to which dual mode can be added in the future. But it was not my purpose to defend any particular dual mode design, nor was it my responsibility to do the job of a booster by proactively casting all dual mode in the best possible light.

The main thrust of my concern with dual mode, and therefore my preference for Personal Rapid Transit is, as I have stated already, to evaluate it as a public policy option, with an eye to rating its applicability to contemporary issues and short & medium term societal goals. The issues are congestion, and related provisions for the free movement of people and goods. The timeframe ranges from current action to a time only a few years in the future: in other words, achievable strategies for solutions demanded by the public, that will attain results in a timely manner at an affordable price. In my opinion PRT remains the best means of addressing today's transportation crisis in a timely manner--

  • ULTra and Taxi 2000 are mature PRT designs which from all indications can be widely implemented now, affordably. Two and possibly three other PRT designs are possibly also at this stage.
  • PRT will not take away or threaten the right to own or operate a private car, it merely proposes comprehensively "better" transit service which will lead to a greater transit share of daily travel (greater than bus or conventional rail).
  • Unlike conventional transit, PRT could be built and operated without subsidy, leaving public funds for necessary improvements to the existing highway system.
  • In my opinion PRT is still better at offering a public transit option which is significantly better than the status quo. As far as I can see, the kind of dual mode which eschews PRT still requires the user who wants on-demand service to drive a car. The public transit user must still ride a bus-- in some systems the bus is really nice, or small, or frequent, or demand-dispatched, but it's still a bus.
  • Emphasizing short term options in this dialogue or on my PRT web page does not mean I don't care about long term needs, or that I think there will never be a place for dual mode. On the contrary, I do see a need for such planning as well as development of technology to meet long term goals. It's just that I don't have an interest in doing a web page about it. Perhaps a hemispherical dual mode network like that dreamed of by Mr. Reynolds is what we'll wind up with. Maybe it will be RUF, or MAIT, or ETT. Those designing these and other systems should continue their efforts; society will choose and adopt them at its own pace. And maybe the transportation technology of the late 21st century has yet to be dreamed of. Whatever technologies end up being dominant, it won't be happening for a long time. The "paradigm shift" (an overused term but appropos in this context) which will be required is huge, in terms of the individual mindset as well as cities, industries, and maybe entire nations which will have to undergo major restructuring to take advantage of the new transportation paradigm. A recent Seattle Times article said even Mr. Reynolds thinks his dual mode design won't be realized for another 50 years.

    I'm doing my small part to make PRT happen in my community a little sooner than that.


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    Last modified: August 06, 2002