90-Second Headways

The elusive 90-second headway. Like a unicorn, or Sasquatch, or some other mythical beast, the promise of waiting no more than a minute and a half for a train during rush hour is what keeps some us going.

But apparently, this wouldn’t be good for service. A study conducted in 2006 by SYSTRA for WMATA used a proprietary software tool called the RAILSIM network simulator, which sounds like fun and I’d like to get my hands on it. But most intriguing were their findings on ATO and higher headways:

SYSTRA also investigated the feasibility of operating trains at 90-second headways on the Metrorail system using RAILSIM Network Simulator and a modified version of the database previously developed for the Metrorail network. SYSTRA evaluated the simulated running times to develop minimum supportable headways and sustainable train separations for each line in each direction. The analysis results show that the Metrorail system can operate on 90-second headways at most system locations when necessary to achieve schedule recovery after a delay has been incurred. However, 90-second headways offer no schedule recovery capability and should not normally be reflected in a scheduled operating plan.

I think essentially what the last point means is that if you’re running 90-second headways and you get an offload, or whatever other issues might will arise, it’s hard to run enough replacement trains to pick up the slack. Which seems like a valid point. But of course, if we were running 90-second headways – or even 3 minute headways – the crowding issues that offloads result in now would be minimized.

Still, at any rate, it’s nice to see that dreams are possible – even if they haven’t yet come true.


History Repeating

I lived in ____ for 10 years before moving to the _____ area in 1989. The _______ subway 12 years ago was terrifying. Creaky, ancient, clattering, graffiti-plastered trains swayed along tracks warped through years of deferred maintenance. Most subway cars weren’t air-conditioned. Tunnel trash fires were an everyday occurrence. Delays were the rule, not the exception. Coming from Chicago, where riding the “L” was a fairly comfortable and reliable, I was stunned.

Guess which subway she’s talking about? Because it sure does sound familiar. The answer: New York. And in ‘89 she moved to the Washington area.

Though I’d like to read what comes next, unfortunately it’s a pay archive article. Still, obviously they fixed things in New York – can we be next?

More What-Might-Have-Beens

I love the alternate history game. And as it turns out, several US cities were in contention for the Olympics this year, and so alternative visions of a Games that never were have abounded. New York is an interesting example, where in the end, some several billions of dollars worth of the proposed venues and other improvements were built anyways.

But did you know there also might have been a DC 2012? It’s true! Apparently, it would have been more of a regional bid than anything, with venues stretching from Baltimore to Annapolis to West Virginia. But could it have been done?

Of course the DC 2012 planners thought so. But as the past decade has shown, it would almost certainly have been an unmitigated disaster. Reason #3 why DC “was qualified” to handle the Olympic games?

Mass Transit To Handle The Crowds 
The Olympic and Paralympic Games are about moving thousands of people with ease and comfort. We are blessed with a mass transit system that allows us to say with confidence today that this will be a breeze. From Washington, DC’s acclaimed, accessible METRO system, to Baltimore’s Light Rail we have the resources to move the expected visitors, athletes, and officials sure to be here in the summer of 2012. Our area has over 450 miles of rail line to move passengers and we expect to call heavily on the resources of not only METRO and Baltimore’s Light Rail, but also on the MARC, VRE , and Amtrak systems. We’ll also press in to service the thousands of busses that regularly move commuters and tour groups throughout our region.

Oh, fine then, totally. Can’t imagine any breakdowns ever of this wonderful, well-networked transit system. Also – where is all this “acclaim” and “belovedness” I hear about so often? I’m pretty nostalgic for the past myself, but that particular chapter of history seems lost…

Visions of a present that could have been are nice. But about as outlandish as I can picture is a week without offloads or headways longer than 8 minutes. That would be a truly great accomplishment.