WMATA has posters in many stations to make the public aware of its online chats. The posters show a young man whose face is lit up with the delight of receiving a "straight answer." However, as Friday's chat with Metro CEO Richard White shows, such straight answers can be difficult to obtain.
But first, an introduction: I'm Omari Norman, and I'm happy to join the team here at Live from the Third Rail. I live in Silver Spring, Maryland and work for the federal government, so you'll find me riding Metro's Red Line to work every day. I rely exclusively on public transport, so you'll also catch me riding Metro on the weekends. I ride a bus from time to time as needs warrant.
White's online chats are part of his effort to communicate with his customers, and I appreciate his effort. It seems he does learn new things in each of his chats, and he often promises to look into problems that customers bring up. Unfortunately though, he often does not provide straight answers to relatively simple queries. For instance:
Perhaps White is being intentionally evasive, or perhaps his sketchy answers are the result of mere oversight. But I would appreciate more direct answers from him in the future. He need not tell us what we want to hear--he could have told KSilver that "we aren't going to make the print in bus timetables larger; it uses too much paper. Get over it." Or he could have told me that "it's too tricky to ensure that four-car Red trains operate only between Silver Spring and Grosvenor, so it's just too bad that the four-car trains leave people on the platform at Wheaton." At least then he would have been being direct and honest.
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massysett | 10:31 AM |
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Omari -- It seems like the 4-car trains go to the end of the line because trains would be more packed, rather than less.
There's a minimum separation between trains on any transit system; let's say two minutes. If you interleave a four-car train between six-car trains, you'll be able to pick up about 10 cars worth of people every 4 minutes, and drop 10 cars worth of people off at or near the end of the line.
If you turn the four-car train around partway, your six-car trains don't get any closer together. They're still four minutes apart, but now, they're all you have, so you're now picking up 10 cars worth of people every 4 minutes downtown, and dropping those people off with 6 (very full) cars every 4 minutes at the ends of the line.
Also, many of those people would have to get off at Grosvenor, and wait for the next train, since they boarded the short train.
???--Frank, could you (or anyone) explain this a little bit? I do not understand how a four-car train would be *more* crowded even if it is serving seven *fewer* stations. Maybe it just makes no intuitive sense and so it needs further explanation.
At any rate, Metro does not seem to have any sort of policy regarding the usage of four-car Red rush hour trains. Sometimes they run Silver Spring to Grosvenor, sometimes they run Shady Grove to Glenmont. Perhaps the replacement four-car takes the same schedule of the broken six-car train it is replacing. Assuming you are right, they should take all the four-car trains and run them to the end of the line. My point is that Metro has no consistent policy regarding how they use these four-car trains. It would seem to me that with a little foresight and manipulation, they could help minimize inconvenience to customers at Glenmont, Wheaton, Forest Glen, White Flint, Twinbrook, Rockville, and Shady Grove. All of these stations seem to suffer the most to me when these four-car trains run to the end of the line, because these stations have less frequent service than the others. If one train is too full to board, the customer must wait five minutes for the next train rather than 2.5 minutes for customers at, say, Silver Spring.
Omari -- the controlling factor for how many trains can run isn't how long the trains are, but how far apart they are. If the minimum is 2 minutes, for instance, you could run an 8-car train every 2 minutes, and your system will never be able to carry more people than that (US transit stations, except in NYC, are built 600 feet long, for 8 cars).
From the perspective of a rider exiting the train before Grosvenor, you may be right that the four-car trains wouldn't be crowded: If so, it would be because that capacity is now being jammed into even more overcrowded six-car trains serving riders going beyond Grosvenor. Those trains now have to be at least 2x the minimum separation ('headway'), to make room for your four-car train.
Since most US subways serve suburban and exurban commuters, it's likely that a lot of riders are going out to the parking lots at White Flint, Twinbrook, Rockville and Shady Grove, and those passengers would only be able to board every other train, leading to congestion on platforms and on board those 6-car consists.
Once the four-car consist is in use, it doesn't help to take it out of service before the end of the line, because it's taking up a spot in line, and you can't usually drop a 6-car train into its place once it turns around (you can only add trains coming out of yards, or coming off a siding, which means parking it there before you need it). If you do turn it around, you have half as many trains going to the end, and only 60 percent as many cars (6 vs. 10 in any given period of time).
Hi Frank--
I still don't understand. You're aware that, during most of the time that Metro is open, only half of Metro's Red Line trains run all the way to the end of the line at Shady Grove and Glenmont? The other trains terminate at Silver Spring and Grosvenor. There are pocket tracks at these two stations where trains reverse direction. Only late at night (both during the week and on weekends) do all Red Line trains run to the end of the line at Shady Grove and Grosvenor.
During a rush hour when all of Metro's equipment is operative, they run 44 6-car trains on the Red Line. Only 22 of these trains operate between Shady Grove and Glenmont. The other 22 operate between Silver Spring and Grosvenor. Thus, with a given level of staffing and equipment, Metro can provide more frequent service on the Silver Spring-Grosvenor segment.
But sometimes it seems Metro is short on equipment. (This happened just yesterday, for example.) So they might have, say, only 43 6-car trains and 1 4-car train.
The question is, where does this four-car train operate? Just yesterday I saw a four-car train during rush hour. Destination: Shady Grove. Behind it was a six-car train. Destination: Grosvenor.
Given that half of the Red Line trains operate Silver Spring - Grosvenor only, why on Earth does it make sense for Metro to put the four-car train on the Shady Grove - Glenmont beat? I'm saying put that train on the shorter segment! Indeed, during weekends Metro does this routinely: 6 car trains on Shady Grove to Glenmont, 4 car trains on Silver Spring to Grosvenor.
Omari -- here in Atlanta, our similar situation is on the East-West line, where 4-car trains run from Bankhead to either Georgia State or sometimes King Memorial.
In the situation you're talking about, where some trains are turning around, I agree, it would make sense to have the shorties do the turning. But if the 4-car train is an emergency fill-in (as your 43 + 1 example suggests), you want that train to do the most good it can (it's probably picking up passengers who have been waiting for 10 minutes or more), and that means going to the end of the line.
Of course, once it's turned around, they should probably put it on a siding and return it to the normal 4-6-4-6 alternating pattern, with a Grosvenor destination.
f--- you ---hole, thousands of people are standing around for 15-30 minutes up in forest glen, wheaton, glenmont, and a bevy of west-side red-line stops because ----faces like you are telling wmata that you want limited-service trains. die in a metro rail fire.
