Questions and Answers from Chief Operating Officer Brian Dwyer and Chief Safety Officer Theresa Impastato
As Metro marks the one-year anniversary of a 7000-series (7K) railcar derailment on the Blue Line that resulted in no injuries, we are sharing an update about our work to restore the fleet. In the absence of a definitive root cause, much of Metro's 7K fleet was sidelined. The path to adding more frequent service, reducing crowding, and serving new stations requires the gradual return of all 748 7K railcars.
Q. Why is Metro not running 7Ks on all lines?
A. Metro has taken a metered and gradual approach to return the 7K fleet back to passenger service which allows us to continuously evaluate and improve our process. During Phase 1 of our return to service plan, we concentrated efforts in rail yards that support Green and Yellow Line service and ran trains mostly on those lines. In Phase 2, the WMSC required limiting operations to the Green, Yellow and Red Lines, allowing us to continue to collect data relative to the interaction of the trainsets with the track infrastructure. At this point, we have requested approval from the WMSC to expand 7K operations to all lines.
Q. How did Metro inspections change?
A. Metro initially requested a seven-day inspection interval in our original Phase 2 submission but accepted the WMSC's request to return the fleet to service with a daily inspection interval and progressed to a four-day interval in order to keep the process to return more 7Ks to service moving forward. We have requested approval from the WMSC for a seven-day interval, which was first submitted on September 28 and resubmitted per the WMSC's request on October 13. Both plans were derived from the results of the fleetwide inspection that occurred after the derailment, the available data on historical exceedances, and the data collected through 67,952 inspections and 2.7 million miles safely run since June 2022.
From this data set, the worst-case wheel movement was calculated as a function of time, and the minimum inspection interval of 10 days was determined. Metro conservatively applied a 20 percent safety factor to the calculation, reducing the inspection interval to eight days. Introducing additional safety factors, the interval was further reduced to seven days. We are currently seeking WMSC concurrence to move to a seven-day interval.
Q. Metro seems to have had problems following its plan. Can you explain what happened?
A. In accordance with our conservative approach, the process for inspection requires multiple points of redundancy. This redundancy, paired with a series of restrictions (e.g., segmentation of the fleet, limitations on service areas, multiple systems of record, etc.) create several opportunities for procedural errors to occur. To date, there has not been an error which resulted in a train operating in an unsafe condition. Each issue has been thoroughly investigated to identify opportunities to prevent future process occurrences. It should be noted that Metro's submitted plan accounts for these lessons learned and offers less complexity and fewer opportunities for error.
Q. Are the 7Ks safe?
A. Yes, the 7K railcars are safe. The 7Ks cars are the newest and most reliable cars in our fleet, meeting the industry's state-of-the-art design standards for crashworthiness with interior safety features including onboard cameras for added security. Since they entered service, these trains have traveled more than 440 million miles. Since June, railcars have traveled 2.7 million miles, the equivalent of approximately 42,000 trips around the Capital, and proven nearly four times less likely to experience failures that require removal from service, reducing inconvenience to customers.
The process to measure the wheelsets that Metro has put in place exceeds industry best practices and provides new quality control and assurance practices, as well as advanced data management.
Q. What caused the Blue Line derailment?
A. We still have no direct root cause(s). As the movement of wheels on an axle is a rare occurrence in the transit industry, Metro enlisted experts to perform multi-factor analyses and testing to identify potential causes in support of the National Transportation Safety Board (NTSB) investigation. Metro has also created an inter-disciplinary engineering team of subject matter experts to review the interaction between Metro's trains and track infrastructure. As the investigation continues to progress, we await determination of a definitive cause(s) and recommended engineering solutions. Over the past year, Metro has worked closely with investigators, outside safety officials, third-party experts, and the railcar's manufacturer to optimize our efforts to detect and address any conditions which may contribute to the movement of wheels in order to safely return the entire 7K fleet to service. An additional third-party expert was recently hired to implement best practices in strengthening our railcar data collection system; assist with our 7K return to service program; manage our drive-thru inspection technology program; assess and provide recommendations to improve Metro's Railcar Maintenance & Inspection (PMI) program.
Q. Why is Metro not running 6-car 7K trains?
A. Metro's 7000-series trainsets were safety certified to operate as eight-car trains, comprised of two, four-car sub-units. The trains are designed for two configurations, referred to as A and B cars. A-cars include an operator's cab and B-cars do not. The current tested and certified configuration of the trains is in an "A-B-B-A" "A-B-B-A" configuration. To run the trains in a six-car configuration would require extensive testing and modifications to the trainset software which must be safety certified. Metro has prioritized devoting the engineering and safety resources on the return to service of as many 7K trains as possible, in their current configuration.
Q. Why is Metro not running every 7K car?
A. As we are supporting the efforts to determine root cause of the wheel movement, Metro has been working to evaluate a number of potential variables that contribute to this phenomenon as we refine our process. Initially, Metro was limited to eight trains. Metro elected to limit the cars to newer cars, with the lowest mileage and least wear.
In Phase 2, Metro was instructed by the WMSC to run cars based on press tonnage in passenger service. Press tonnage is the force that is applied in mounting the wheel to the axle. While Metro was given permission to operate up to 20 trains, the restriction of train cars at the higher press tonnage limited the number of trains that could run to 16 trains daily.
For months, Metro has operated 7K trains for testing and training purposes under the exact terms that we included in the Phase 3 proposal. We believe this demonstrates the safety of our approach and aligning our processes is both prudent and efficient. We have provided data to the WMSC to support all trains moving to the seven-day inspection interval.
Based upon an analysis performed by independent experts, Metro believes that the press tonnage of the fleet does not present a hazard. In fact, we have experienced slow wheel movement in fractions of an inch on axles that have utilized both the lower and higher press tonnage. In our latest Phase 3 return to service plan revision, Metro has requested the approval of the WMSC the ability to utilize our entire fleet, regardless of press tonnage.
Q. Is it safe to ride Metro?
A. Yes, Metro is safe. Transit is one of the safest modes of transportation available to the region. Metro is diligent in monitoring our performance and identifying opportunities for improvement. We regularly perform benchmarking to evaluate our performance relative to our peers in the industry. A review of the past five years of operational safety data from the National Transit Database indicates that Metro's safety performance in multiple areas is among the best in class. Transit agencies are required to report incidents and accidents to the National Transit Database each year. Derailment reports include incidents involving work equipment and in yards, which accounts for the majority of derailments WMATA reports. Last year only one derailment involved a passenger train. Data for all systems can be found here. Metro's rate of rail system incidents such as collisions, derailments, and customer injuries are consistently among the lowest in our cohort. We strive to continuously improve and frequently collaborate with our peers to share information and identify best practices. Year over year, Metro's performance has improved in key areas.
Q: What can Metro do to reduce existing crowding?
A: We have safety crowding concerns. To reduce crowding on Metrorail, we need the following:
- All 748 7000-series railcars for passenger service (first time since October 2021)
- 7000-series trains in service on all rail lines
- Protocols to measure wheels every seven days
Q: Why does Metro need WMSC's concurrence to run 7Ks on the Silver Line in order for the extension to open by Thanksgiving?
A: Metro needs the WMSC's concurrence this week to safely move trains (mostly in limited overnight hours) into the various yards to support the restoration of service for stations south of National Airport, and to mobilize trains for the start of passenger service at Dulles Rail Yard. Additionally, Metro needs to align real-time communications systems and finalize other details to support passenger service. Local bus service providers have also requested a minimum of three weeks' notice to provide connecting service to new rail stations.
The return to service plan provides changes needed for both increased service frequency for customers systemwide and the Silver Line extension.
Q: Why is Metro running two different inspection protocols: one for employee trains and one for customer trains?
A: The WMSC has approved two different inspection protocols - one for employee trains (every seven days) and one for customer trains (every four days). Metro does not believe there is any reason to distinguish between the two trains types. The plan seeks to reconcile the two current processes, as both are safe. It should be noted that for months, Metro has operated 7K trains for testing and training purposes under the exact terms included in its Phase 3 proposal on all lines, which demonstrates the safety of its approach.
Q: Has Metro gotten any recommendations from NTSB or WMSC?
There has been no recommendation from the NTSB or WMSC. The NTSB investigation has not yet identified a root cause for the derailment. Meanwhile we have developed an industry-leading inspection process in which we have high confidence.
Q: In rejecting Metro's Phase 3 plan, how has the WMSC contradicted its response to Metro in their current letter?
- The WMSC letter indicates that there are differences in the track interface with trains on Blue, Orange, Silver Lines that requires monitoring, then indicates permission to run on those lines temporarily, but offers no metrics for successful completion of that experiment;
- The letter implies that Metro could swap axles to increase the fleet; however, that is operationally infeasible and would impact Metro's ability to safely and efficiently manage its fleet, as well as changes many variables at once;
- WMSC approved trains under a seven-day inspection interval for employees to test and train on all lines, but customer trains must be inspected every four days and are restricted to Green, Red and Yellow Lines.
- In December 2021, WMSC approved use of the 7Ks fleet on all lines, with a seven-day interval with no new analysis indicting issues with this protocol coming to light since that time.
In fact, all the analysis conducted since December of 2021 supports returning the full fleet under the provision requested in phase three.