Tag Archives: rolling stock

More train doors and wider doors will help WMATA capacity

It’s always fun to stumble across official analysis that mirrors your own – even if some of the conclusions differ.

With a hat tip to Kurt Raschke, I came across this document outlining WMATA’s challenges in providing capacity in the core of the system. Most of the white paper focuses on potential increases in rail capacity from changing WMATA’s signalling system from the current fixed-block system to a CBTC-based moving block system (they do not find a large practical boost in capacity from such a change).

The document is part of making the long-term case for additional rail tunnels through downtown. In order to justify that expense, they are addressing some of the preliminary alternatives to squeeze more capacity out of the existing system (organization before electronics before concrete). From the executive summary:

As train and station congestion worsens, a question logically posed by stakeholders and the public is” “Why can’t Metrorail add more trains to relieve the crowding?” The fundamental purpose of this White Paper is to present the root causes of Metrorail capacity constraints that limit service expansion in the core.

One thing that jumped out at me was the suggestion of procuring new rail cars with more doors and wider doors – a suggestion I’ve made before.  More doors can better handle boarding and alighting, reducing station dwell times, and thereby improving both capacity and reliability. The benefits are substantial (emphasis added):

[T]he benefits in terms of reduced dwell times for a 60 second dwell time would likely be in the range of 8-12 seconds (a 20-30% reduction in that portion of the dwell associated with passenger alighting/boarding with no effect on the base door cycle time dwell component of about 20 seconds). Assuming all cars of all trains have four doors per side, this is equivalent to a throughput gain of about 2 trains per hour.

The white paper also includes this table (which bears a striking resemblance to one I put together several years ago):

WMATA Capacity Analysis, comparison of ingress/egress for rail cars in peer systems.

WMATA Capacity Analysis, comparison of ingress/egress for rail cars in peer systems.

Despite the obvious benefits of this change, the white paper downplays the potential for increasing the system’s overall capacity. Addressing them one by one:

As shown in Table 9, relative to car length, the boarding and alighting capacity of Metrorail vehicles closely matches the capabilities of peer systems’’ vehicles. WMATA’s rolling stock matches the median of those sampled for both the number of doors per unit car length, and the total door width per unit car length, though both of these values are slightly below the mean. While procuring or modifying vehicles to increase the number and size of doors may conceivably increase the rate at which passengers could board and alight, it would be an unconventional method for increasing total passenger carrying capacity.

I wouldn’t agree with the statement that all of these railcars closely match. In the rightmost column (inches of door width per foot of car length), you’ll see that the busiest of WMATA’s peers have a door capacity 50% greater than WMATA, or more.  The difference between WMATA’s 2 in/foot and Toronto’s 3.2 in/foot is huge.

Second, the major benefit to adding more doors isn’t an increase in absolute capacity, but to improve reliability and the passenger experience. More doors means a smoother flow of passengers on and off trains. Faster station dwells, particularly at crowded transfer points, reduces the likelihood of passengers holding doors or missing a train because of a lack of time to board.

Next: the time required to make this change.

Although this rolling stock change could be implemented incrementally as each Metrorail fleet type is retired, full implementation would require over 40 years due to the life cycles of the multiple Metrorail fleets.

All the more reason to get started with a four-door design for the next rail car series! And another reason to consider the design of the 7000 series a missed opportunity.

What about lost seating?

Second, implementing a new railcar design with four doors per side would result in a net seat reduction of approximately 28 percent, requiring more customers to stand.

I’m not sure where this calculation comes from; a cab car (A-car) from WMATA’s 7000 series seats 64 with the current arrangement and 58 with a longitudinal-only seating array. Toronto’s Rocket cab cars feature a similar rail car size (75 feet long) and feature four wide doors per side; they still manage to provide 53 seats, representing a 17% decrease over the 7000 series seated capacity.

WMATA’s own actions show that seated capacity isn’t a primary consideration. WMATA has been slowly reducing the number of seats per rail car series and increasing standing room with each new version; the original 1000 series had seating for 82; the 2000 series sat 76 per car; the 5000 series seats 68, and the 6000 series seats 64.

Given the stated goal of this white paper to determine potential for long-term solutions to WMATA’s core capacity challenges, I hope they don’t discard the idea of adding more doors to the future railcar fleet. Combined with some other suggestions, there’s a great opportunity to improve both the system’s capacity and reliability.

Improving passenger information in WMATA’s 7000 series railcars

As more of WMATA’s new 7000 series railcars enter service, more riders get a chance to experience the new cars in regular service, under the demands of everyday use. The same is true for me – after several chances to ride the new cars in regular service, I have a few observations – particularly relating to passenger information.

I’ve written previously about the big-picture issues for WMATA’s next railcar design: maximizing the usefulness of the existing system means changing railcars to more efficiently move people through the system – and that means more doors, wider doors, open gangways, different seating arrangements, etc.

There’s also room for improving the passenger information systems. The 7000 series include lots of new features, including real-time displays and automated station announcements. Each car has two types of LED displays – a screen that can scroll any kind of text near the end of each car, easily visible from anywhere onboard, and a variable display showing the next stops the train will serve.

7000 series information displays - photo by the author.

7000 series information displays circled in red – photo by the author.

The ‘next stop’ displays above the windows (modeled after the FIND system on several NYC subway car types) contain useful information, but the actual LEDs do not read well at the angles available for most passengers in the car. Even moving closer to the sign doesn’t help much, particularly when compared to the sign at the end of the car:

Comparison of visibility of LED signage in WMATA 7000 series railcars. Photo by the author.

Comparison of visibility of LED signage in WMATA 7000 series railcars. Photo by the author.

None of the next few stops are nearly as visible from this vantage point as “Franc-Springd” at the end of the car. Reading the display more or less requires standing directly in front of it; a challenge compounded by the seating layout, placing 2×2 seating directly under the ‘next stop’ displays.

WMATA 7000 series next stop displays. Photo by the author.

WMATA 7000 series next stop displays. Riders must be in front of the displays to read the LEDs. Photo by the author.

By contrast, New York’s FIND displays are located above center-facing seating. This both puts the displays in a line of sight for people sitting on the opposite side of the railcar, but also takes advantage of the additional standing room in New York’s subway car design.

Completely re-arranging seating layouts or changing the location of these signs is a big change. But there are other opportunities to improve passenger information for users. In addition to the LED signs, each 7000 series car includes four video-capable monitors per car, located adjacent to the doors:

WMATA 7000 series video screen. Photo by the author.

WMATA 7000 series video screen. Photo by the author.

Currently, the screens display a strip map (updated in real time) in the top half of the screen, rudimentary information about the station services (for example, a note that you can transfer to Metrobus – but not any particular route information) in the lower left, and a rotating ad space in the lower right corner (in this photo, listing WMATA’s website).

The above photo illustrates one of the biggest problem with these displays – they do not read well at a distance. Discerning any of the information requires moving closer to the display.

Photo by the author.

Consider another example of a similar technology from a bus in New Zealand, using larger text that can be easily read at a distance; displaying the travel time (in minutes, not number of stops) to the next few stops, as well as the end of the line; and putting less important information in a smaller typeface.

fidlerbusscreentweet

Displays within railcars in Paris use a similar approach (image from Transitized) with large text (easily visible), focusing just on the next two or three stations, along with the estimated travel time to key transfer points as well as the end of the line.

Information about the current stop and next stop should be available for riders to consume instantaneously. Editing the amount of information and using large type reduces the time required for riders to process that information – to say nothing about the need to move through the car to take a closer look.

The nice thing about software is you can change it. WMATA and the District DOT recently installed real-time arrival displays at numerous bus shelters in the city. At first, the displays took too long to cycle and scroll through extraneous information. After some initial testing, the displays now show more useful information to riders at a glance – no need for scrolling or displaying the arrival times for buses scheduled to arrive in the distant future.

New software and a different approach to displaying information on these screens could make them more useful – and potentially help cover for the visibility issues with the above-the-window next stop displays.

The importance of more & wider doors for future Metro railcars

CC photo from Stephen Evans

CC photo from Stephen Evans

This week, WMATA awoke to a nice present sitting under the tree. The first of the 7000 series railcars is here. These new cars will expand the fleet, increase the system’s capacity, and replace the oldest railcars in the system. All worthy ends, and all goals that the 7000 series will help meet.

However, like the economists pondering the economic inefficiency of Christmas, I can’t help but wonder what the 7000 series could look like if the gifts under the tree were exactly what you wanted. In that regard, the 7000 series design falls short. The good news is that there will be more railcar procurements in the near future.

The key shortcomings of the 7000 series are not technical (yet! we will need to see how they perform once in service), they are based on policy and assumptions about what a WMATA railcar is. Engineering-driven technical changes include a slight repositioning of the door locations and improved car body crash energy management.

At the same time, the assumption of the car design is to avoid changing the fundamental WMATA rail car concept (three doors per car, lots of seating for a commuter/metro hybrid). This means that the aesthetic changes to the 7000 series aren’t just about the end of Metro Brown. The altered door spacing and adherence to the original concept (three doors per car, three windows between each door) makes for awkward proportions – all in the name of leaving the original concept unexamined.

The good thing about assumptions is that they’re easy to change — once you change your mind. In California, BART struggles with the same legacy of operating a rapid transit/commuter rail hybrid. Despite the shortcomings of BART as a planning/construction agency, BART the operating agency is moving in the right direction. BART’s new rolling stock makes a couple of big changes, such as adding an additional door per car, embracing the rapid transit reality for the system.

Embracing the status quo is easy for any institution. That inertia is hard to overcome. Contrast BART’s changes to the most recent railcar procurement in Chicago, where the biggest changes are in the technical systems and seating layout.

I outlined some key ideas for the 8000 series in a previous post, but I wanted to put some numbers together to make the case for one of the most visible changes: wider doors, and more of them. The chart below summarizes the key dimensions from a selection of railcars:

Railcar Door Comparison

A Google docs spreadsheet with the above data is available here.

I chose the cars on this list for a variety of reasons. I mentioned RATP’s MP-05, used on the now fully automated Line 1 in Paris, and Toronto’s Rocket in a previous post. BART’s inclusion shows both old and new cars, demonstrating what can be gained from change. Using BART as a comparison point for WMATA is also useful due to the similar age and history of the two systems. And, as a counterpoint of traditional mass transit, I included examples of relatively new cars from New York’s A and B division.

Each of these examples represents a somewhat pragmatic choice; I wanted to include others but could not easily find online specifications on door opening widths. Basic dimensions on car/train length is easy to find, but door opening width is harder. Transport for London is one exception, with excellent online information from the agency itself, rather than from third parties. London’s new S7/S8 cars would be a good example to include, but TfL has not yet updated their rolling stock information sheet to include them.

Online sources:

The table shows  the impact of both the total number of doors, as well as the width of the doors. WMATA’s 50 inch doors are relatively narrow; all of the other examples are at least a few inches wider. The one exception is New York’s R160, but the R160 makes up for those narrow doors with overall numbers: Four door openings per 60′ rail car, compared to WMATA’s three doors per 75′ car. Each door on the MP-05 in Paris is 1.65 meters wide, showing how wide you can go – wider than WMATA by more than a foot.

The big reason to add doors is to improve/reduce station dwell time. The rightmost column illustrates the benefits of many wide doors: more space available to move between the train and the platform. When an 8-car WMATA train arrives at a platform, passengers must squeeze into 16.67% of the train to board/alight. Contrast that to the MP-05s used on Line 1 in Paris, where 32.9% of the train is available for passengers to pass through from train to platform. To put it another way, if WMATA wanted to offer that same permeability between the train and platform without changing door width, they would have to double the number of doors.

Line 1 in Paris is an exceptional case, where RATP is attempting to squeeze every last bit of capacity out of century-old tunnels. In the traditional rapid transit cases, each of the New York examples is greater than 25% door width to platform length. Toronto’s Rocket shows what WMATA would need to do to get to that standard: four doors per car, and modestly widen the doors to ~60′ per opening.

BART’s new rail cars won’t achieve the 25%+ of Paris, New York, or Toronto; but adding the third door to their new rail cars will beat WMATA at 19.3% and offer a substantial increase from the two-door model.

A simple re-evaluation of what WMATA’s assumptions about what a  rail car is can go a long way towards the goal of maximizing the capacity of the existing system.

The future of Metro’s rolling stock – ideas for the 8000 series

At some point in 2014, WMATA’s newest rail cars, the 7000 series, will enter service. These cars will depart from the same basic design of all of Metro’s current rolling stock in a couple of ways. However, despite the accolades of the new designs from Metro, the 7000 series design misses some key opportunities to squeeze extra capacity out of the system and run the trains more efficiently.

While the ship has sailed for the 7000 series, all is not lost. WMATA will need to eventually expand the fleet and replace the remaining older rail cars; and will do so with the yet-to-be-designed 8000 series. (WMATA current has four cars with 8000-level numbers from the 1000-series, comprising the money train.) Depending on the source, design work on the 8000 series could start between 2018 and 2020; the lead time for developing a new rail car is long; note this article on the 7000 series (again, set to enter service in late 2014) dated from January, 2008.

The 7000 series has potential to improve reliability and operate efficiently: WMATA’s contract holds the builder to meet or exceed a standard of an average of 150,000 miles between failures (WMATA’s current fleet achieves just over 60,000 miles between failures; 150k represents an improvement, but still shy of NYC’s fleet average, yet alone the performance of NYC’s newest railcars).

Efficient and reliable systems will be an important improvement, but they don’t address some of the broader elements of a good rapid transit system. With an eye towards improving the 8000 series, and after riding modern rolling stock in other cities around the world, I’ll offer some suggestions for future railcars in DC.

Maximize the number of doors: While riding Line 1 of the Paris Metro under crush loads, one thing that amazed me was the consistently short station dwell times. As a train pulled into a station, large numbers of people would board and disembark within a matter of 10-15 seconds, and then the train was on its way. Contrast that against WMATA during peak hours at one of the key transfer stations (Metro Center, L’Enfant Plaza, or Gallery Place): I’ve often seen train operators start to close the doors after 20-30 seconds, but people were still getting off of the car, to say nothing of those waiting to get on.

Metro’s current rolling stock features only three doors on each side of a 75-foot long rail car (New York gets four doors to fit on a 60-foot long rail car; Toronto’s new cars feature four doors on a 76 foot long car) Increasing the number of doors on each train makes the exchange of passengers from train to platform easier and faster, particularly with large crowds. The added ease also improves the reliability and consistency of station dwell times. Wider doors are also an option; the MP-05 trains in Paris operating on Line 1 feature three sets of wide doors per side of each 50-foot long rail car.

Paris Metro MP-05 train with wide doors. Note the lack of a cab due to fully automatic operation. CC Image from Wiki.

Paris Metro MP-05 train with wide doors. Note the lack of a cab due to fully automatic operation. CC Image from Wiki.

Despite pleading from train operators, when the dwell times are not long enough for passengers to board/alight, they will hold doors open. This introduces the potential for delay, both by degrading WMATA’s schedule adherence, but also by risking a door malfunction that will take the train out of service. WMATA’s procurement documents for the 7000 series sought a “proven linear door drive system” to improve reliability; however, changing the system’s design (by adding more doors) has the opportunity to improve efficiency and reliability above and beyond the technical systems.

Open gangways: More doors improves passenger flow between the train and platform; removing the doors within the train allows passengers to move along the entire length of the train. This increases capacity and improves the passenger experience, allowing them to naturally balance the load and move along the train if one car is too crowded.

IMAG1471  IMAG1474

Looking through the open gangway of new S-stock in London, and at the floorplate in the gangway going around a curve. Photos by the author. 

The most compelling reason is additional capacity. In Toronto, the new ‘Rocket’ subway cars increased capacity by 8-10 percent. London’s new Sub-surface rolling stock features open gangways between cars, as does the MP-05 stock in Paris. New York is considering open gangways for future railcar procurements.

When asked about why the 7000 series did not include open gangways, Metro cited vague concerns about safety where a suspect might roam throughout the entire train. Yet, in New York, politicians have cited the inability to move between cars as a threat to safety. Both arguments rest on dubious assumptions, but appeals to a vague sense of safety cannot trump the obvious boost of an additional 10% capacity.

Seating arrangements: During discussions about the 7000 series, WMATA opted to keep the current seating arrangement, dominated by forward/rear facing seats, rather than sideways-facing seats that maximize standing room. In WMATA’s own mock-ups, the loss of seated capacity is minimal (about 8 seats per married pair, or 4 seats per car on average). While bench-style seating is common in Europe, is is not used exclusively – though all of the newer railcars make a strong effort to increase standing room and improve passenger flow within the car.

Interior layout of MP-05. CC image from Wiki.

Interior layout of MP-05. CC image from Wiki.

For example, consider the option of using forward/rear facing seats as singles instead of doubles. WMATA’s transverse seating is usually arranged 2+2, with a fairly narrow aisle. The MP-05 rolling stock in Paris uses a 2+1 combination, in addition to substantial center-facing seating. London’s S-Stock offers a variety of options, as does Toronto’s Rocket. Extensive use of flip-down seating adds flexibility for a variety of users, offering seats when necessary, but providing additional standing room during peak hours.

Passenger information: One of the most obvious improvements for passengers on WMATA’s 7000 series will be “next stop” displays (noted for the prototype’s typos), similar to the ‘FIND’ system in some of New York’s subway cars. These displays offer a strip map of the line, showing the next stations. However, more is possible. In Paris, the digital displays in the MP-05s not only display the upcoming stations, but the time to the end of the line, as well as major upcoming transfer points.

Above-the-door strip map for Line 8 in the Paris Metro. Photo by the author.

Above-the-door strip map for Line 8 in the Paris Metro. Photo by the author.

Digital displays offer flexibility to the operator to use trains on any line. However, many operators nonetheless use old-fashioned, route-specific strip maps.

Even though it’s not a subway or rapid transit application, the in-train displays from the Netherlands are impressive. The screens show the current route, next stops, scheduled arrival time and track. When arriving at a station, the in-train displays will show platform information for connection trains, allowing passengers to head directly to that platform. In the event of a delay or change in the schedule, the displays update immediately.

Blurry photo of info screen inside an NS InterCity train, with arrival and connection information. Photo by the author.

Blurry photo of info screen inside an NS InterCity train, with arrival and connection information. Photo by the author.

Overall: I’ll note that none of these are new or unique ideas; Matt Johnson (open gangways; more doors) and David Alpert (transverse seating) both suggested similar changes for the 7000 series. I’ve offered suggestions in the past, as well.

Toronto Rocket technical drawing. Image from Bombardier.

Toronto Rocket technical drawing. Image from Bombardier.

You don’t even need to look overseas to see many of these ideas in action. As mentioned above, Toronto’s new Rocket subway cars incorporate most of these ideas. WMATA has the same opportunities. Toronto’s Rockets feature permanently married 6-car trainsets (the maximum length for Toronto’s system), four doors per 76-foot long car, and lots of standing room without removing all transverse seating – something to aspire to for WMATA’s next railcar procurement.