The Secret Worldwide Transit Cabal
Tuesday, August 26, 2003
"Big Tom" & His 90-mph Van
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"Truth passes through three phases: 1) It is ridiculed. 2) It is violently opposed. 3) It is accepted as self-evident." Albert Schopenhouer. In the United States, rail is currently passing through Phase Two.
From the Cabalmaster:
The Secret Worldwide Transit Cabal is pleased to bring to you the following commentary on speed, inspired by lugubrious lamentations overheard by an FOC about “all those cars over there [on a nearby highway] going faster than the train].
We’re opinionated ( . . . as you know by now . . . ), and we don’t think that public transit has to provide a minute-for minute match with auto travel times. In addition, we don’t think that transit agencies can afford to run at the fastest speed possible between stops just to entertain passengers.
Not convinced, eh? Well, consider the following:
When Bay Area Rapid Transit opened in 1972-1974, trains hit 80 between most stations away from downtown San Francisco and Oakland. This was true even between, for example, Ashby and downtown Berkeley, which are just a bit more than a mile apart.
However, as BART management gradually learned ( . . . the hard way . . . ) how to operate a real railroad in the real world, they gradually realized that 80 mph whenever possible was unnecessary and wasteful.
Unnecessary because such speed is not needed to keep the schedules. The Richmond -- Fremont run, for example, has never been advertised for anything faster than 1 hour (= 40 mph) -- and schedules are significantly more reliable today than they were back then.
Wasteful because unnecessary speed between stations hikes power. Acceleration to 50, rather than 80, slashes power consumption for that acceleration cycle by more than 60 percent. (An FOC tells us that BART and Philadelphia’s PATCO once conducted an informal "competition" to see who could achieve the lowest power consumption). Excess speed also hikes maintenance costs by imposing additional wear and tear on vehicles.
Today, BART trains no longer hit 80 in regular service. The maximum speed, through the Transbay Tube, is about 70. The marginal increase in travel time over most of the system is measured in tenths of a second; even through the Tube (about 5 miles between Embarcadero and West Oakland stations), the slower speed adds less than a minute. Yeah, OK, the ride may be less "exciting," but it's also quieter, and there's no practical reason to run at 80 even between these stations. (The speed-time curves in various textbook illustrate this formally.)
In Dallas, the DART light rail system achieves an overall average "passenger" or "commercial" speed of 20 mph. Timings between some station pairs are faster, but the systemwide average is 20.
Certain members of the opposition love to complain that passenger speeds in this range are "too slow."
We wonder what all the whining is about.
The average travel distance per passenger on the DART rail system is 5.3 miles. Therefore, the average travel time is about 16 minutes.
Hike the "average" passenger speed to 25 mph, and the average travel time becomes 13 minutes.
We think that a three-minute time saving saving per person -- which the "average" person might not even notice -- is simply not worth the investment required to achieve a commercial speed of 25 mph overall.
Another problem: higher speeds tend to generate longer average travel distances, and this can play havoc if you're not prepared. The most spectacular almost-example is the Blue Line in Los Angeles . . . we say "almost-example" because the line had many more cars available than were thought necessary during planning. (The initial order, you see, included cars for the then-unbuilt Green Line).
You may enjoy the following narratives by two FOCs that sum up the issue:
“The American public has some growing up to do when it comes to ‘speed for speed's sake.’ Years ago, my homeboy ‘Big Tom,’ an exceptionally skilled driver and anarchist, demonstrated his contempt for the California Highway Patrol as follows. He brazenly drove between Los Angeles and San Francisco as fast as his van would go – literally. That was 90 on flat sections, and 100 down hills. But the end-to-end tome was an underwhelming 5 1/2 hours [= 73 mph]. Back then, six hours [= 67 mph] was a reasonable estimate for this drive, assuming no traffic jams and no stops [and no encounters with ‘Ponch and Jon’]. The van used so much gas – you could see the gas needle move – that he had to stop four times for gas. OK, I admit, it was fun, but we didn’t get there much faster. Public transit should NOT cater to this impulse.”
The other FOC writes:
“It’s true that transit is slower than driving for many trips, but this shouldn’t be the only consideration. For example: If you’re 35-45 (non-rush-hour) minutes away from Manhattan, San Francisco, or Washington DC by car [roughly 30-40 miles], you may have high-quality transit or commuter-rail option that will take about an hour. So, why use transit (which, in New York and the Bay Area, ain’t cheap for such a distance)? Well, if you have to ask, you’ve probably never tried to find parking in Manhattan or downtown San Francisco. Also, ‘driving time’ is ‘wasted time,’ unlike ‘transit-riding time’ which I can use for reading or working on my laptop. And so, why not transit, even though it's 15-25 minutes ‘slower?’”
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