Silver Line / Blue Line problems

An interesting analysis: WAMU.org

Some snips:

Among Metro's 'Hard Truths' Are Silver Line Problems With No Easy Fix

But Metro’s internal analysts and outside observers agree some problems may be intractable in the short-term. The opening of the Silver Line 20 months ago caused a ripple effect across the entire rail system, creating new problems while compounding old ones for which there is no easy solution.

From its impact on the Blue Line to the bottleneck at Rosslyn, from the lack of working railcars to low ridership, the Silver Line expansion through Tysons Corner has thus far proved a Pyrrhic victory.

Silver throttles Blue

The Silver Line’s expected impact on other lines was detailed in documents more than a decade ago during planning for the 11-mile extension through Tysons Corner to Reston. Metro’s plans to realign Blue and Yellow Line service, now known as Rush+, date to 2008.

Blue Line headways — the interval between trains — would double from six to 12 minutes to accommodate the Silver Line; Metro encouraged Blue Line riders to switch to Yellow for D.C.-bound commutes to the eastern side of downtown.

The no easy fix was self inflicted when the board made the decision to scrap the 4 and 5k cars. They can convert that no easy fix into an easy fix by retracting that decision and do the midlife rehabilitation to those cars. The result would be a 448 increase in the fleet size instead of the 64 car increase in the fleet after all the 7k car are delivered.

I think Metro had to choose between rehabbing the 4k and 5k cars OR buying additional 7k cars. Metro chose additional 7k cars because they figured they would ultimately last longer since they could be rehabbed again later.. while the 4k and 5k would have one more "life" then be retired.. forcing metro to again buy more railcars.

So if they change their decision now.. that will lower the amount of 7k cars to 428 instead of 748.

"Chris Brown"
I think Metro had to choose between rehabbing the 4k and 5k cars OR buying additional 7k cars. Metro chose additional 7k cars because they figured they would ultimately last longer since they could be rehabbed again later.. while the 4k and 5k would have one more "life" then be retired.. forcing metro to again buy more railcars.

So if they change their decision now.. that will lower the amount of 7k cars to 428 instead of 748.

No. If they change their decision it will increase the fleet size by 284 cars as the plan now is to replace both the 4 and 5k car with 7k cars.

The original schema for the 7k car procurement was:

Base order 64 Dulles Phase I
Option 1 64 Dulles Phase II
Option 2 130 Fleet growth to support 75% 8 car trains
Option 3 100 Rehabilitate 4k cars
Option 4 300 1K replacement
Option 5 90 Fleet growth to support 100% 8 car trains

Total new 7k cars 648

The schema now is:

Base order 64 Dulles Phase I
Option 1 64 Dulles Phase II
Option 4 300 1K replacement
Option 3 100 4K replacement
Option 2 130 5k replacement
Option 5 90 54 5k replacement 36 Fleet growth

Total new 7k cars 748

The 7k car procurement morphed from increasing the size of the fleet to accommodate Silver line, 300 car replacement and 100% 8 car trains schema to an increasing the size of the fleet to accommodate Silver line, 584 car replacement and an increasing the size of the fleet by 36 cars.

With the attention placed on WMATA in recent months, now might be the time to ask for money to either expand the 7k order or arrange to rehab the 4/5ks. Probably the former - the production line is still running, the newer cars will have a much longer lifespan (hopefully), and politicians and the public love seeing "brand new" rather than "restored antiques."

As for the SV/BL issues, I think a return to ATC will reduce the headways. I'm interested in seeing more/extended hours for Yellow Rush Plus too, since it's just as fast to get to Metro Center via transfer to OR/BL/SV at L'Enfant as it is direct BL via Rosslyn. Short of a new bore and new alignment (up through Georgetown? Along the Mall?) that's the best us riders can hope to have.

Returning to ATO isn't going to change a damn thing. Everyone seems to think there is some magic to ATO over manual, because that's how WMATA's PR team likes to spin things. ATC/ATP provide speed commands to the train, regardless of who or what pushes the throttle. In manual mode, the train operator sees a speed command and operates throttle in response to that command. In Automatic, the train's onboard computer sees the exact same speed command and operates the throttle automatically. The headways are no different, the speed is no different, the stops are no different, the number of trains are no different. The red line crash in 2009 would have happened regardless of ATO or manual. The train would have received the same 55mph speed command, proceeded into the occupied block, and crashed into the undetected stopped train. Disabling ATO was a smoke screen to make people feel safer. Just like bellying the 1000 series cars was a smoke screen to make people who don't understand physics feel safer.

The congestion and long headways is 100% mathematics. Not enough rolling stock, and not enough tunnel. Unless you add more rolling stock and add more tunnel, the problem doesn't go away. This problem was known for years and WMATA decided it was acceptable.

mtuandrew wrote:With the attention placed on WMATA in recent months, now might be the time to ask for money to either expand the 7k order or arrange to rehab the 4/5ks. Probably the former - the production line is still running, the newer cars will have a much longer lifespan (hopefully), and politicians and the public love seeing "brand new" rather than "restored antiques."

As for the SV/BL issues, I think a return to ATC will reduce the headways. I'm interested in seeing more/extended hours for Yellow Rush Plus too, since it's just as fast to get to Metro Center via transfer to OR/BL/SV at L'Enfant as it is direct BL via Rosslyn. Short of a new bore and new alignment (up through Georgetown? Along the Mall?) that's the best us riders can hope to have.

Rehabbing the 4K and 5K cars is almost as expensive as buying additional 7K cars. It would be nice if Metro could buy all 748 of the 7k cars AND rehab the 4k and 5k on top of that. But I don't think they have the funding at the moment, nore do they have enough space in their current rail yards to park all these cars.

But retiring rail cars halfway through their life is kind of wasteful. There is still time for a change of heart down the road. It will be at least 3 years before the last 1k car is gone. By then, they might decide they can afford to rehab the 4K and 5k cars instead of junking them, but doubt it. Those cars will be even more outdated by 2019. The first 7k cars were built in 2012. By 2019 they will already be 7 years old. Can you believe it?

"MCL1981"
The congestion and long headways is 100% mathematics. Not enough rolling stock, and not enough tunnel. Unless you add more rolling stock and add more tunnel, the problem doesn't go away. This problem was known for years and WMATA decided it was acceptable.

The railroad is presently being operated at roughly 60% of its designed capacity (24 TPH). With more rolling stock you could push that to 75% (30 TPR). 30 TPH should be the goal before adding more tunnels and stations.

"Chris Brown"
Rehabbing the 4K and 5K cars is almost as expensive as buying additional 7K cars. It would be nice if Metro could buy all 748 of the 7k cars AND rehab the 4k and 5k on top of that. But I don't think they have the funding at the moment, nore do they have enough space in their current rail yards to park all these cars.

According to WMATAs own numbers not including Dulles Yard the storage capacity is 1316 with Dulles yard the number jumps to 1520. Storage capacity is not an issue however the balance of the storage capacity is. Alexandria, Shady Grove and Glenmont are negative in excess storage capacity.

But retiring rail cars halfway through their life is kind of wasteful. There is still time for a change of heart down the road. It will be at least 3 years before the last 1k car is gone. By then, they might decide they can afford to rehab the 4K and 5k cars instead of junking them, but doubt it. Those cars will be even more outdated by 2019. The first 7k cars were built in 2012. By 2019 they will already be 7 years old. Can you believe it?

They won't be out dated if they are rehabilitated to the same specifications of the 7k cars. The original schema for the 7k car procurement had the 4k cars rehabilitated to be totally compatible with the 7k cars.

Sand Box John wrote:"MCL1981"
The congestion and long headways is 100% mathematics. Not enough rolling stock, and not enough tunnel. Unless you add more rolling stock and add more tunnel, the problem doesn't go away. This problem was known for years and WMATA decided it was acceptable.

The railroad is presently being operated at roughly 60% of its designed capacity (24 TPH). With more rolling stock you could push that to 75% (30 TPR). 30 TPH should be the goal before adding more tunnels and stations.

My understanding is the tunnel under the Potomac maxes out at 26 trains per hour. It's a bottleneck that no amount of added rolling stock can overcome. Since WMATA is too much of a mess actually maintain 26 trains per hour on a good day, it's really more like 20 trains per hour at the most. Split equally between three lines, you're looking at 6 trains per hour on each line, which is a train every 10 minutes for each line on a really good day. The orange and blue line got more trains than blue, so the blue line has 12+ minute headways, while the orange and blue have shorter headways. Unless they build another tunnel or bridge, this won't change.

"MCL1981"
My understanding is the tunnel under the Potomac maxes out at 26 trains per hour. It's a bottleneck that no amount of added rolling stock can overcome. Since WMATA is too much of a mess actually maintain 26 trains per hour on a good day, it's really more like 20 trains per hour at the most. Split equally between three lines, you're looking at 6 trains per hour on each line, which is a train every 10 minutes for each line on a really good day. The orange and silver line got more trains than blue, so the blue line has 12+ minute headways, while the orange and silver have shorter headways. Unless they build another tunnel or bridge, this won't change.

Your understand is based on the propaganda coming from the entrenched suits that occupy the Jackson Graham Building. The train control and signaling system is designed to accommodate 40 TPH. The only thing preventing them from running anything above 26 TPH is sufficient quantities of rolling stock.

Higher TPH would reduce crowding from the station entrances to the seats aboard trains because it would be spread the loading over more trains. It would also reduce the amount of time needed to discharge and board the trains allowing shorter dwell times.

Can traction power support 40 trains per hour in the tunnel, or anywhere else for that matter? A train every 1.5 minutes sounds like a pipe dream given their chronic mismanagement.

Really? 40TPH is going to fix the overcrowded platforms, chokepoints created by everyone exiting through one escalator?

Get real. 26TPH is overachieving considering how mismanaged the system is. They shouldn't even try to go beyond that.

"MCL1981"
Can traction power support 40 trains per hour in the tunnel, or anywhere else for that matter?

The only areas of the railroad that would likely not be able support it are on the trunks segments and on the Red line between the short turn terminals.

Back in the 1980s before WMATA finished taking delivery of the more power hungry Breda cars they routinely operated 30 TPH or higher.

A train every 1.5 minutes sounds like a pipe dream given their chronic mismanagement.

See below.

"YOLO"
Really? 40TPH is going to fix the overcrowded platforms, chokepoints created by everyone exiting through one escalator?

How many stations have only one exit escalator where peak volume would need more. I can't recall of any. Oh and 40 TPH doesn't mean that one of those trains will be loaded to the same level as one of the train from a 26 TPH operation. 40 TPH is a kin to putting the same amount of peanut butter from two sandwiches into three.

Get real. 26TPH is overachieving considering how mismanaged the system is. They shouldn't even try to go beyond that.

The mismanaged is nothing new, blame can made to both the staff and the board. There's been a hell of lot of fixing of things that weren't broken if you get my drift.

MCL1981 wrote:Can traction power support 40 trains per hour in the tunnel, or anywhere else for that matter? A train every 1.5 minutes sounds like a pipe dream given their chronic mismanagement.

Traction power is an issue but hardly insurmountable; just add a few more MVA.... Platform crowding is a bigger issue....

More trains would REDUCE platform crowding. I'm going to use fake number for discussion purposes. 10,000 people are trying to go from Shady Grove to Metro center over the course of an hour.

If there are 15 trains per hour, meaning a train every 4 minutes, that's 666 people crammed into each train, and dumped onto the platform every 4 minutes. All 666 trying get through the doors, up the escalators, and out the fare gates at once.

If there are 25 trains per hour, meaning a train every 2.5 minutes, that's 400 people cramming onto each train and dumped onto the platform. 400 people trying to get through the doors, up the escalators, and out the gates.

If there are 40 trains per hour, meaning a train every 1.5 minutes (laughable as that may be), that's down to 250 people trying to get through the doors, up the escalators, and out the gates.

More trains per hour doesn't increase the number passengers per hour. But it does spread the same number of passengers out evenly over time, reducing the crush loading and and stampedes. You have a steady and manageable flow of 300-400 people moving smoothly through the system. Rather than a crush of 500-800 people, a lull, another crush of 500-800 people, and so on.

Now that said, we all know the mismanagement will never get them beyond 20-25 trains per hour on a good day. That's a lot of juggling, and it would require essentially doubling their train operator staff during the peaks. It's never going to happen. Increasing the number of 8 car trains, and reducing the instances of breakdowns and track/signal disruptions is the only way they're going reach their peak performance and satisfaction. At least on the red, orange, yellow, and silver lines. The blue line is screwed no matter what since they're running three lines through the core on one set of tracks.