All Things WMATA 7000 Series

I'm now entering my 4th straight week of not riding a 7K, although do see them very sporadically. Interestingly, according to WMATA's GIS data there is only one 6-car train in rush-hour operation; the rest are all 8-cars, so theoretically the Red Line could have been 100% 8-car trains.

I finally went to the east side of the Red line surge and a lot of the 7k's are over there. Also, today is supposed to be the last day of the SafeTrack surge on the Red line so hopefully we will see things return to normal by tomorrow or next week.

I tested my theory this weekend to see if a lot of the 7k's were moved to the Green line. Surprisingly, I saw mostly older cars outside of the 4 car set they were testing (7232-7235). There was a time when the Green line was mostly 7k's too. So now I'm thinking many of them might be on the Orange and Blue lines. I'm going see if I can visit the Orange and Blue lines this week to test this theory.

There's currently 56 7k cars stranded at Glenmont Yard due to SafeTrack activities. Some of those went OOS very early in that surge because they had improperly adjusted collector shoe assemblies knocked off. Some of them are stuck because of poor planning - they're overdue for PM inspections. The rest have legitimate failures. Because there's no shop available on that isolated portion of the line, they've just been sitting there collecting dust.

They have various Diesel locomotives. They can not tow them to Brentwood, etc???????

Well, WMATA must have read my last post because of course I rode on a 7K this morning. Also, it seems like there are a lot of 6-car trains on the (western) Red Line today.

farecard wrote:They have various Diesel locomotives. They can not tow them to Brentwood, etc???????

There really was no way to get the trains out during Safe track. The Eastern leg if the red line was cut off from the rest of the system during the Safe track surge. The tracks were barricaded just below For Totten, which included the B&E connector. There was 24/7 track work going on, which would prohibit any moves across the work area. Brentwood Yard was also cut off from revenue access during the surge; no cars were assigned to the yard, only a couple long term jobs remained there through the surge. Glenmont Yard was all they had on the east side, and they did a good job factoring in spares.

I think some field repairs could've been made for the shoe disabled trains if it were absolutely necessary. Just kill power to the rail and get to work.

Of course this is a moot point now that the safe track work is done and the line is opening up soon.

smallfire85 wrote: There really was no way to get the trains out during Safe track. The Eastern leg if the red line was cut off from the rest of the system during the Safe track surge. The tracks were barricaded just below For Totten, which included the B&E connector. There was 24/7 track work going on, which would prohibit any moves across the work area. Brentwood Yard was also cut off from revenue access during the surge; no cars were assigned to the yard, only a couple long term jobs remained there through the surge. Glenmont Yard was all they had on the east side, and they did a good job factoring in spares.

I think some field repairs could've been made for the shoe disabled trains if it were absolutely necessary. Just kill power to the rail and get to work.

Of course this is a moot point now that the safe track work is done and the line is opening up soon.

I hear Metro's ultimate goal with the 7k cars is 200,000 miles without failure. What I'm wondering is why they are not coming off the assembly line perfect right now. Is Metro still finding design flaws and other issues?

I suspect Metro might have rushed mass production to accommodate the added strain on the fleet from the Silver line and to hurry the retirement of the 1k and 4k cars. Doesn't seem like the 7k's are a perfect product just yet.

To remedy the issue of 7k cars losing contact with the third rail (which was raised in particularly problematic spots), the collector shoes have been lowered on the fleet. https://www.washingtonpost.com/news/dr- ... 03a668ab61

If the shoes on the 7k's were ordered with the same specs as the legacy fleet.. I don't get why this would happen. Also, what is the purpose of the "'safe mode''? It seems to cause more problems than is solves by stranding trains when its not really necessary.

Did you notice chief smoke blower Stessel's comments on this? First he describes all these problems with the cars that leave them stranded in tunnels with no power and rip components off. Then says that the repairs and adjustments are not because of a problem with the cars, but rather because they simply want to enhance the customer's experience.

Either WMATA changed the specs for the contact shoes when they ordered the 7k cars (stupid) or Kawasaki didn't follow the specs correctly. I find it hard to believe Kawasaki who has been making subway cars forever would screw something like that up though.

The 7K collector shoe design is indeed different from those on the legacy fleet, from what I've been told. They apply different amounts of pressure to maintain 3rd rail contact.

It's only in the last week that I actually rode a 7000 consist. I rather like the destination display with the next n stations. But I am struck by the fact they do not make any reference to arrival time. I guess that has to do with managing rider's expectations.....

It also duplicates the LCD monitors to some extent, but are far more legible in sunlight....

The good thing about LED and LCD signs and screens is you can always change the display later without spending much money. Nothing on those signs and screens is necessarily carved in stone.

I'm sure the LCD screens will eventually be used for ads. And they should be since Metro needs the money. It would also be nice if they had a system map showing the location of your train on the map. Currently they just show where your train is within a small portion of the line.. which is kind of redundant since the strip map over the windows shows the exact same thing. I actually heard a tourist complain how it doesn't show the entire system map.

The 7000 cars use the same exact collector assembly as the 5000 and 6000 series cars. Up until this, all series used identical height and pressure criteria.

The difference with the 7000 cars seems to be in the primary suspension - chevron springs - which are reacting unpredictably to varying passenger load weights. The resilient rubber that comprises the bulk of the chevron spring assembly is a composite material that can vary in proportion between batches. In addition to changing the shoe paddle adjustment criteria, we're also experimenting with testing the chevron springs upon installation and introducing shims based on their stiffness.

The Breda cars also use chevron springs but those cars use a different type of collector assembly.

The so-called "safe mode" is a great capability that was added to 7000s for good reason. It's not possible to determine whether the loss of traction power is intermittent or more serious, and you don't want to put the train in a configuration that leaves it unable to complete ascending a grade due to insufficient propulsion - or unable to stop rolling back due to insufficient air pressure (loss of traction power also disables the air compressor). Better just to stay put where it's safe.

Of course none of this would be an issue if the third rail plant was maintained as it should be.