Monday, February 22, 2010

The ROTC Drill Sergeant Had It Right: ‘You Can’t March Your Platoon Faster than the Slowest Man’

Funny how things said to you decades ago can come back like pearls of wisdom to put current issues in perspective. Take the architects’ insistence that Honolulu’s rail system could be built both at-grade and elevated.

About a million years ago, ROTC cadets at my Iowa high school heard our program’s active-duty sergeant shout out this nugget so often I can still hear his voice:

“Gentlemen, you can only march your platoon as fast as the slowest man!”

The message was absolutely clear. Try marching faster than your unit’s capability and you’ll end up with disorder and chaos. With that as background, here’s an exchange during last Thursday’s “Insights on PBS Hawaii” TV panel discussion show on the Honolulu rail project.

We started our review of the program a few days ago and now pick up the program during a discussion on whether the partially at-grade system proposed by the local chapter of the American Institute of Architects would have the same carrying capacity as the City’s proposed all-elevated 20-mile system between East Kapolei and Ala Moana Center. Host Dan Boylan directed a viewer’s question to Peter Vincent of the AIA's Rail Task Force:

Boylan: “Peter, someone wants to know: Does the light rail proposal change the per-hour capacity?”

Vincent: “Yes, somewhat, but it exceeds the demand. In other words, the persons per hour per direction in the EIS proposed by the City is 63 hundred. It was subsequently increased to 81 hundred. The (AIA proposal of) light rail transit – three cars of approximately 90 feet each running at 3-minute headways (the time between trains) – would be slightly over 9 thousand people. Maximum capacity if the headways were increased (sic) down to say a maximum of 2 minutes would go up to a capacity of 12 thousand passengers per hour per direction, so it exceeds the anticipation of the City.”

Councilman Gary Okino: “Logically it just doesn’t make sense. An (elevated) train that travels (an average of) 30 miles per hour, which can go 60 miles an hour, rather than a train on the ground that can average only 10 to 15 miles an hour, how can you say that has more capacity than the elevated system? Logically, it just doesn’t make sense.”

Vincent: “The system that was proposed by Phil Craig, the transportation consultant that we’ve been consulting with and (who) wrote a report that Kamehameha Schools, did quite an in-depth study, and his analysis – which requires further study, of course – it was detailed nonetheless, and based on 50 years experience and extremely detailed knowledge of transit systems across the world, recommended half elevated, half at-grade system. Most of the area that I showed in the picture earlier from East Kapolei coming into Waipahu could and certainly should be at grade. That’s going to run as fast as an elevated system because there’s virtually no interference there. Then the system in the highly congested area of Pearl City and going into the airport would be fully elevated and thereby traveling at the same exact speed of the proposed all-elevated heavy rail system, and then going at grade. So the difference in time going from East Kapolei to downtown is only 3 minutes more with the combination light rail elevated/at-grade system, and then it slows down a bit more – another 9 minutes going from in-town to Ala Moana Center."

City Managing Director Kirk Caldwell: “Councilman Okino said if you’re going at-grade in town and you go only 14 or 15 miles an hour, the rest of the system cannot go any faster than that, otherwise all the cars are going to be piling up against each other. The beauty of a grade-separated system, whether it’s elevated or underground, is no matter what’s happening on the ground, it can go consistently (an average of) 30 miles an hour. Every 3 minutes a train will come at rush hour, every 6 minutes non-rush hour and every 10 minutes during the very slow periods of time no matter what’s happening. But if you’re on the ground, you can go no faster than the slowest car in your system. Again, (what Vincent is saying) does not make sense. It sounds great, but when you think about it, it doesn’t make sense.”

Vincent: “It works in 34 other U.S. cities.”

Caldwell: “But it doesn’t go as fast. We’re paying for a system that’s fast and efficient. We’re trying to get (people) out of their cars who live in the ewa plain to come into town. If you don’t make it fast, if you don’t make it reliable and if you don’t make it efficient, they’re not going to get on it. They’re going to drive into town.”

Former Council member Gary Gill: “They’re not going to get on TheBoat (meaning a slow train) because it doesn’t run on time and sometimes it breaks down. So, let’s not do 'TheBoat thing.’”

Summary: Comments and claims made on a “live” television show come fast and sometimes furiously, and it takes transcriptions like this one to pick out the issues that require additional reflection. Peter Vincent’s assertion that at-grade rail’s headways (time between trains) could be 3 minutes or even only 2 minutes is one such issue.

Unlike architects, transit experts will tell you headways between trains driven by humans must be considerably greater than automated trains. Three minutes between trains with humans at the controls seems highly unrealistic, and Vincent’s suggestion that headways could be only 2 minutes for at-grade trains seems fanciful at best.

Another point Vincent made needs amplification – that at-grade trains could consist of three cars, each 90 feet long. Two hundred seventy feet (3 x 90) happens to be the approximate length of the shortest block in Chinatown, and an at-grade train can’t be longer than the shortest block to avoid blocking cross streets.

But the City’s elevated system can be longer than the shortest city block because trains would be completely unaffected by cross streets, so it’s obvious an elevated system with trains that each have greater capacity and operate with at shorter headways is much more efficient in moving large numbers of people than at-grade could ever be.
A third point is the proposal Vincent alluded to by New Jersey-based consultant Craig, whose suggested alignment of an at-grade system through the heart of downtown Honolulu and around the Iolani Palace-Capitol-City Hall complex would necessarily require slow-moving trains -- a point we made some months ago. Check out the map of Craig's proposed route at this link.

As Managing Director Caldwell said during the show, …if you’re on the ground, you can go no faster than the slowest car…. That's pretty much what Sergeant Phillip Spinabella was trying to get across to his ROTC cadets decades ago.

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