Passenger Trains > [DC] The "Rosslyn tunnel bottleneck"

Transportation Nation has a short article about the problems on the DC Metro with the opening of a part of the new Silver Line. Blue line trains were cut from the schedule due to capacity issues in a key tunnel. That led to over crowding on some remaining trains. Now it has been determined that Metro is operating fewer than the maximum number of trains through the tunnel.

(The issue is similar to the ongoing issue in NY and NJ, where a century old tunnel is at capacity, even as commuter and longer distance travel increases. Unlike NY NJ, the alternative in DC is a series of free roads and bridges, not the $15 toll crossings.)

>>According to data provided by Metro and compiled by MetroMinder DC, an app that measures the rail system's performance, in the first week of Silver Line service (July 28 through August 1), an average 25 outbound trains passed through the bottleneck between 5 to 6 p.m. Between 6 and 7 p.m., the average fell to 23.7 trains/hour.

In the second week (August 4 through August 8), an average 26 trains (the maximum) made it through the bottleneck between 5 and 6 p.m. The average dropped to 21.8 between 6 and 7 p.m., mostly as a result of the disabled train/single tracking on August 6.

MetroMinder compiled data for 24 separate peak-period hours during the afternoon rush outbound at Rosslyn from July 28 to August 13. Metro met the goal of five Blue Line trains 20 times.

Performance varies day to day. On Tuesday, July 29, between 5 and 6 p.m., 26 trains passed through Rosslyn into Virginia. On Wednesday, that number fell to 21, and then on Thursday rose to 24.<<

http://www.wnyc.org/story/measuring-metros-performance-tight-squeeze-through-rosslyn-bottleneck/

Form reading the item, I did not know Metro does not currently use Automatic Train Operation. Has this been the case since the rear ended collision a few years ago? Is there a planned return date?

nm2320 Wrote:
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> Form reading the item, I did not know Metro does
> not currently use Automatic Train Operation. Has
> this been the case since the rear ended collision
> a few years ago? Is there a planned return date?


There's been a related discussion about the signal system, and the software necessary to implement the automatic train protocols. My recollection is DC Metro used unauthorized replacement parts, messed with the rail (something about the conductivity, perhaps), etc. The manufacturer voided the warranties.

Member "Shoretower" (RIP) was extremely versed in that saga, as I recall.