Completion of Red Line Signal Repairs
Posted on September 25, 2019
Signal repair completion results in restoration of regularly scheduled Red Line service
Today the MBTA announced the completion of all Red Line signal repair efforts, resulting in the restoration of regularly scheduled Red Line service.
Efforts to restore the signal system between JFK/UMass and North Quincy, which were completed this past weekend, were followed by several days of operational testing. As with the restoration of previous segments of the signal system, operational testing ensures the system is properly functioning and can be monitored and controlled by the MBTA’s Operations Control Center.
“While I’m pleased Red Line service has been restored, this event underscores the level of urgency we need to continue to build a better T,” said MBTA General Manager Steve Poftak. “I want to express my deepest gratitude to our customers for their patience while restoration work took place. I also want to thank our entire workforce and contractors for their efforts to work seven days a week to restore the system to normal.”
Today: Regular Red Line Service Has Resumed
With this final work finished, regular Red Line service has been restored in all areas, including all previously affected areas on both the Ashmont and Braintree branches. With fully functioning signals, countdown signs at all previously affected Red Line stations are also back and turned on.
The MBTA began running 28 trains on the Red Line during rush hour last month after restoring a key area of signals between Broadway and JFK/UMass, which is the regular number of trains scheduled to operate during peak periods. As of last week, these 28 trains have returned to their pre-derailment schedules with about 14 trains running per hour through the downtown area of the Red Line, or about 1 train every 4 to 5 minutes during rush hour. During the mid-day, the Red Line is also back to operating between nine and 10 trains per hour.
In the days that followed the Red Line derailment in June, the Red Line was only able to run approximately six trains per hour during rush hour service, or roughly 1 train every 10 minutes. During the mid-day of the days that followed, the Red Line ran about five trains per hour.
Due to the significantly damaged automatic signaling system, a manual operation was put in place at the time on the Braintree branch from Broadway to North Quincy and on the Ashmont branch from Broadway to Fields Corner. The process of manually moving each train through each station in these sections of the Red Line required about 57 personnel in the field every day.
Throughout the summer, the MBTA continued to make incremental progress. Due to this progress, last month the area of manual operation was scaled back to two areas between JFK/UMass and North Quincy on the Braintree branch and to between JFK/UMass and Fields Corner on the Ashmont branch, requiring about 41 personnel in the field per day. Progress also allowed the MBTA to continue to near pre-derailment rush hour levels of service with 28 trains back on the Red Line during rush hour periods. The T was also able to operate 3 additional trains during off-peak hours in an effort to provide more frequent service and minimize crowding during the middle of the day.
The Recovery Effort
After the June 11 derailment, MBTA work forces and contractor personnel worked 7 days a week to make major repairs to signals, communications, and power infrastructure. In July, 3 signal bungalows had been rebuilt, a new, fourth signal bungalow was constructed, and repairs were made to numerous signals, switches, nearly 20 miles of signal cable, hundreds of signal control relays, dozens of track circuits, and numerous other pieces of related equipment. In August, major signal work was completed in the key area of signals between Broadway and JFK/UMass Stations, allowing the T to increase the number of trains operating during rush hour and improve travel times. As of last week, all restoration work was completed with final repairs made to train control signals, track signals, and electronic track switching controls.
During the recovery effort, the following was accomplished:
- Immediately following the derailment during the period of time when Red Line service was replaced with shuttle buses, 44 emergency shuttle buses were deployed to carry passengers.
- Numerous MBTA Engineering and Maintenance personnel worked to safely remove the incident train, restore track and traction power, and supported the entirety of the recovery effort.
- Every day during that 106-day period, numerous signal personnel removed, tested, and installed signals and cables while commissioning four phases of recovery in the area near JFK/UMass Station known as the Columbia Junction.
- The MBTA’s subway operation team installed dozens of flagging personnel, officials, and staff during the period of time when each Red Line train was manually moved through affected areas.
- During this manual operation, the MBTA’s Safety Department dispatched personnel to support the safe movement of trains along the tracks and ensured the safety and wellness of all employees every day.
- Throughout this period, the T’s Vehicle Maintenance team made detailed inspections of the entirety of the Red Line fleet.
- Numerous support contractors assisting with redesign and reconstruction as well as Keolis staff and MBTA employees from Capital Delivery, the Red Line, the Orange Line, Railroad Operations, Customer Experience, System-wide Accessibility, Communications, and more assisted in supporting recovery through their respective departments.
What Happened: The Cause of The Derailment
At the September 16 Joint Meeting of the MassDOT Board and Fiscal and Management Control Board, the cause of the June 11 derailment was discussed. Engineering analyses of various components of the Red Line car involved in the incident were performed with disassembled components from the affected car further evaluated by a metallurgical lab to determine the root cause.
A fractured axle was found on the incident car. Age, material flaws/defects/weak points, and a failure of the car’s bearings (which allow the axle to rotate) were ruled out as having caused this axle failure.
After further analyses, it was found that the incident car’s fractured axle was caused by a poor electrical connection between 2 train car components adjacent to the car’s axle – the ground brush and the ground ring, which directs electricity that powers the car from the third rail to the car’s motor and out of the wheel through these components. This poor electrical connection caused stray electrical arcing on the surface of the axle. Over a prolonged period of time, this stray arcing caused the solid-steel axle’s mechanical properties to harden, becoming brittle and weak. This weakening of the axle through the direct and prolonged exposure to electrical arcing ultimately caused the axle on the incident car to fracture and fail.
Post-Derailment Inspection Updates
Immediately following the incident, a number of corrective actions were taken. An ultrasonic inspection using sound waves was completed on the entirety of the Red Line car fleet. Able to determine issues small enough to not be seen by the human eye, ultrasonic inspections can detect even the most minute of cracks and flaws that may have the potential to become larger issues.
Out of an abundance of caution, an ultrasonic inspection is also currently underway on the Orange, Blue, and Green Line car fleets and is expected to be complete by the end of next week. Thorough ground ring inspections were also completed on the entire Red Line No. 1 (the incident car was a Red Line No. 1 car) and No. 2 fleets with ground ring inspections on the remainder of the rail fleet also underway.
Going forward, 8,500-mile preventative maintenance inspection procedures (that are already standard procedure) have been updated to include a very detailed inspection of ground rings. These inspections occur about every three months. Annual engineering axle inspections have also been updated to include a full inspection of ground rings. All rail car axle ultrasonic inspection intervals are changing from bi-annually to annually.
MBTA and Red Line Investments
The $8 billion that the MBTA plans to spend over the next 5 years is the most in any 5-year period ever—and this funding will have tangible results and provide a more reliable ride for our customers.
The MBTA is investing nearly $2 billion in the Red and Orange Line improvement program, which will completely replace the cars, replace the signal systems, and upgrade track and maintenance facilities for both lines.
The MBTA is investing $350 million on the signal systems and $470 million for track and maintenance facility upgrades.
The MBTA is working to deliver 252 new Red Line cars and expects the first Red Line pilot car to be delivered later this summer.
The MBTA has also made a number of investments along the Red Line since 2015 including replacing third rail, replacing track, and signal work.