On Monday, June 12, 2017, at about 11:22 PM Eastern Daylight Time, inbound Washington Metropolitan Area Transit Authority (WMATA) Orange Line Train 901 encountered an unauthorized WMATA hi-rail work vehicle fouling the tracks at a grade crossing in approach to Addison Road station.
The incident occurred on the Blue/Silver line approximately six hundred and fifty feet in approach to Addison Road station in the direction of Vienna. Train 901 came to a stop less than five hundred feet from the vehicle after the Automatic Train Protection (ATP) subsystem stopped the train. After moving the train a couple of hundred feet, the operator of Train 901 then obtained a visual sighting of the hi-rail work vehicle on the track and stopped the train manually.
There were no injuries or damage reported during this incident.
At approximately 11:10 PM on June 12th, a Metro track crew called in a track outage request between Stadium-Armory and Morgan Boulevard stations to install new cellular radio equipment along the inside of the tunnels between those stations. A hi-rail unit, a specialized pickup truck designed to run on railroad tracks, was scheduled to be used during the outage.
The hi-rail unit, HR260, checked in on the radio to notify the Rail Operations Control Center (ROCC) that they were at the grade crossing located at track location chain marker G2 462+00 and ready to travel to the work area. The grade crossing location reported by HR260 turned out to be the incorrect location by approximately two thousand feet; the grade crossing is at chain marker G2 282+00, not G2 262+00. The ROCC gave the hi-rail operator permission to board the unit, but specifically prohibited the operator from entering the tracks in the area. The hi-rail operator then failed to clearly repeat back all directions given by the ROCC, but the ROCC controller did not request additional clarification to ensure the hi-rail operator understood the instructions given.
The road crossing where the hi-rail vehicle would have entered the WMATA roadway is located at chain marker G2 482+00. Trains in approach to Addison Road from Morgan Boulevard approach this location on a right-hand curve while also ascending from the tunnel that runs under State Route 214/Central Ave. Trains are underground in the tunnel until chain marker G2 494+50, a distance of one thousand two hundred and fifty feet from the road crossing.
At approximately 11:22 PM, Orange Line Train 901 to Vienna stopped outside of Addison Road and notified the ROCC that the train had “zero speed commands,” preventing the train from reaching the Addison Road station platform. The ROCC radio controller issued the train a permissive block allowing it to continue forward to the signal inbound of Addison Road station, G03/08. This allowed Train 901 to proceed with zero speed commands at a speed below 15 miles per hour, as enforced by the ATP subsystem.
The operator of Train 901 reported a couple of minutes later that they had a visual on a track unit ahead fouling the inbound track. The ROCC radio controller attempted to verify with the hi-rail unit that it was still clear of the tracks. After several radio transmissions back and forth, both the operator of Train 901 and the hi-rail operator reported that the hi-rail unit was clear of the roadway.
The Automatic Train Control (ATC) system is installed on all mainline WMATA track, and is designed to keep trains safely separated through the use of the ATP subsystem and a network of thousands of track circuits. When a train enters a track circuit, it completes an electronic circuit which can signal the ATC system to slow down or stop the next train behind.
We believe that the hi-rail unit “shunted”—or occupied—the track circuit which the road crossing resides in. With track circuit G03-G2-482 now occupied by the hi-rail unit, the ATP subsystem of the ATC system is designed to drop train speed commands down to zero for the next several circuits behind the train to prevent a collision. Before obtaining visual contact with the hi-rail unit, the operator of Train 901 reported they had “zero speed commands,” after which time the ROCC controller permitted the train to continue moving through to the interlocking west of Addison Road station. The train would have then picked up speed commands again and could continue at normal speeds.
Contributing Factors:
- The ROCC controller did not verify that the hi-rail operator understood they were not permitted to enter mainline track when they initially called in while preparing to head to the work zone.
- The hi-rail operator did not follow Metrorail Safety Rules and Procedures Handbook (MSRPH) Rule 1.79 and properly repeat back the instructions given by the ROCC radio controller.
- The hi-rail operator incorrectly identified the chain marker (CM) of the road crossing and did not initially know the CM when asked. The incorrect CM supplied to the ROCC by the operator of the hi-rail vehicle placed the road crossing west of the Addison Road interlocking, whereas the location of the hi-rail vehicle at the time was actually east of Addison Road station.
Any tips or safety violation reports can be made confidentially to the Rail Transit Operations, Performance, and Safety Group at railtransitops.org/report.
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