Please see also 7/26 update further below.
MBTA General Manager Steve Poftak called me this morning to brief me about the Red Line’s troubles and his response. Below is a summary of our conversation.
The Timeline for Service Restoration
Normally during rush hour, there are approximately 14 trains per hour. Unfortunately, at least through Labor Day, there will only be 10 trains per hour.
The derailed train did severe damage. It knocked out the most complex area of the signal system that controls the Red Line. To keep trains running, the MBTA has a crew of 48 people working to manually control the flow of trains through that area. Management feels that 10 trains per hour is the maximum pace that they can achieve safely using manual control.
Most of the parts in the damaged signal system date back to 1970 and are not available. Crews are picking through the rubble of the signal bungalow to salvage the parts that they can. Reconstructing a functioning signal system will take an unpredictable amount of time, Labor Day is an inside date, not an outside date for full speed restoration.
The MBTA already had a project in progress to fully replace the signal system on the Red Line. Unfortunately, the damaged area was the last area that was planned to be replaced, so that it does not seem possible to skip over repair and go to replacement. Moving to completely modernize the damaged area would take at least a year. So, at the moment, the goal is to repair the damaged signals and restore normal service sooner.
How did the Accident Happen?
The answer is not yet known with certainty, but the train appears to have derailed as a result of some kind of wheel or axle failure. Operator error and track/signal defects have been tentatively ruled out.
Investigators are examining the train car that derailed, but at this point there are lots of elements of the car that are broken. It isn’t easy to identify the part that failed among all the parts that were damaged because of the accident. Identifying the part that failed will require laboratory analysis by specialized metallurgists.
Press reports have noted that the car was placed in service around 1969, but the “trucks”, the wheeled units that the car rides on, were replaced in 2014, so age per se is not obviously the cause of the accident. As the manager noted: “If you replace the ax handle twice and the ax head three times is it still the same ax?”
The MBTA has retained an independent firm, LTK engineering, to complete the investigation in to this derailment and the other recent derailments.
What is the MBTA doing to assure that the Red Line is safe?
There are two different parts of the management process: On the one hand, day to day operations; on the other, capital planning — the repair, replacement and upgrade of the system.
In the short run, the MBTA is responding to accident itself by accelerating routine inspections of Red Line cars to identify any possible points of failure that might lead to a repetition of the derailment. All 68 of the other similar cars have now been inspected.
In the long run, the MBTA is following through on projects set in motion 5 years ago to completely replace the Red Line vehicle fleet and signal systems. These plans should come to fruition before the middle of the next decade.
I expressed that I had a lot of confidence in the MBTA’s leadership on the capital planning side — their efforts have been very ambitious and transparent and will, within a few years result in obvious improvements in service. The Red Line will be very different in a few years.
I said I had less visibility into and less confidence about the day-to-day leadership of the system: How good is the safety culture really? The manager took that question in stride and said that he understood the question, but honestly felt good about it. Not good about the recent incidents, but good about the safety consciousess he hears from workers as he is out and about every day.
He acknowledged the need for more visibility on safety issues at the MBTA board level and said that he had requested that the board form an independent board to review the safety culture. He recognizes that it is not enough to offer his personal assurances to the public — that independent observations are necessary.
Update, July 26
In a conference call with elected officials on July 26, General Manager Poftak and his team reported on progress in repairing the damaged signals on the Red Line. The bottom line is that we will be fairly close to normal service by early in August.
The basic idea of train signals is to assure safe separation of trains by preventing a train from entering a “block”, a stretch of track, before the train ahead has left it. Repair crews have salvaged as much as possible from the damaged signal bungalows and have repaired, tested and placed in service the signals controlling two out of four affected blocks and now expect the third block’s signals to be fully tested and back in service by August 5. The remaining block involves additional complexity and the repair date is uncertain.
For the final block, they are working on two uncertain strategies simultaneously: (1) to repair the old signals; (2) to procure and install entirely new signals. It is soon to evaluate how long either strategy will take. The new signal contract was already underway before the crash happened, but the intention was to do the remaining block last. They have resequenced the contract to address it first, but fabricating the new signals is a more-or-less one-off process and the new schedule is not yet determined.
While signals are not working, T workers need to control the flow of trains manually and this is slower than the automated method. Under normal rush hour conditions prior to the crash, customers could expect trains coming through roughly every 4.5 minutes. That went down to 6 minutes after the crash. Trains are running a little better than that now, but will be down to every 5 minutes or a little better by early August. It’s uncertain when we’ll get back to 4.5 minute rush hour headways.
Note that on weekends and evenings, the frequency may be considerably lower to accommodate repair work. I boarded the Red Line at Fields Corner this Sunday afternoon headed inbound and the advertised spacing was 17 to 28 minutes. I had just missed a train and my wait was at the low end of the range.
In the long term (approximately four years), when the new cars and signals are all in place for the Red Line, we will be down to 3 minute headways, which will amount to a huge improvement over pre-crash normal conditions.