Braking problems putting Muni’s new trains out of commission

Braking problems putting Muni’s new trains out of commission

Issues are the latest to emerge after reports of faulty door sensors, couplers

At any one time, roughly half of Muni’s fleet of new train cars is out of service due to mechanical issues, transit officials acknowledged Tuesday.

Out of just over 50 new light rail vehicles, or LRVs, only 20 to 30 are functional enough to be in full-time service at any point in time.

The rest are in repair for various mechanical issues, mainly braking issues that are causing the trains’ wheels to flatten prematurely. Those wheels are now wearing out far faster than the San Francisco Municipal Transportation Agency expected.

Transit officials revealed the problems at a San Francisco County Transportation Authority meeting Tuesday, where they faced blistering critique from the Board of Supervisors, who also sit on the SFCTA board.

The San Francisco Municipal Transportation Agency and its Muni fleet are drawing increased scrutiny from city officials following media reports that brought to light problems with the $1.1 billion new train fleet. The San Francisco Examiner found the doors’ “sensitive edges” were not properly detecting objects in the doorway during Muni testing, and even caught a woman’s hand and dragged her onto the tracks. Tuesday morning Muni officials announced they would temporarily lock all back doors on its new trains to prevent such issues.

Additionally, NBC Bay Area found faulty couplers on the new trains, the discovery of which stopped Muni from running two and three-car trains.

On Tuesday the Board of Supervisors, acting in its function as the San Francisco County Transportation Authority, demanded answers on Muni’s future fleet. The transportation authority had been set to vote on $62 million to fast-track the purchase of more new trains, but that vote was stopped dead in its tracks after safety issues were discovered.

“That this happened at all is inexcusable,” said Supervisor Gordon Mar, at the meeting. “That we were asked to expedite $62 million to obtain these vehicles while these issues remain is indefensible.”

Many supervisors voiced concern they were kept in the dark.

“I’m a little shocked we are asked to fund a $62 million contract and yet we are not hearing this type of information on what happened and what you have discovered,” said Supervisor Sandra Fewer.

In addition to the issues with the doors and the couplers reported by the media, Supervisor Aaron Peskin, chair of the SFCTA board, told the public during the meeting that he had also learned of braking issue with the new vehicles that leads to the new trains taking too much pressure on their wheels, flattening them.

The flattened wheels are caused by emergency braking maneuvers, which happen more frequently than expected with Muni’s automatic train control system, a known issue between the new train cars and the computer control system.

SFMTA confirmed those issues at the meeting.

“At any given time, only 15-20 of these three-and-a-half million dollar vehicles are on the track at any given time due to the time of wheel flattening,” Peskin alleged. “Would you expound on that?”

“We’ve had more vehicles than I’d like to see out of service due to flat wheels,” Julie Kirschbaum, director of transit at SFMTA, confirmed, but noted that there were closer to 20-30 trains available at any one time.

However, documents obtained by the Examiner show the problem may be more severe than officials indicated at Tuesday’s meeting.

Internal Muni maps show that during days in November, December, and even Monday this week, as few as 13-15 of the new Muni trains were out on the street at any time.

And in an internal Muni memo from November, the “LRV4 Team,” essentially the team testing the new light rail vehicles, reported that the new trains wheels were approaching the end of their operable lives far earlier than Muni anticipated.

“The issue with wheel flats is such that some wheels are approaching condemning limits,” the team wrote. “We are working with Siemens to make trucks and axles available for swap out, even though we did not expect to have to do this so early and our equipment is not yet in place.”

In addition to the braking issue, supervisors also pressed transit officials on the door issue, which as shown in video first obtained by the Examiner, dragged a woman from the platform at Embarcadero Station and onto the tracks on April 12. She was hospitalized and then discharged.

Supervisor Vallie Brown asked for Siemens representatives to verify their doors are safe.

Michael Cahill, president of rolling stock in North America at Siemens USA, the train manufacturer, said you cannot engineer for every possible situation.

“I think one of the things that’s important to remember is that even in the presence of sensors, no system, whether it’s sensors or anything else in terms of technology, carries all the responsibility of safety,” Cahill said.

Cahill said there are sensors in the doors that open in the presence of a hand.

“What about a child’s hand?” Brown asked.

Cahill answered that a child’s hand “would be detected.”

In the end, the supervisors’ questions were summed up by Supervisor Matt Haney.

“It’s absolutely shocking and horrific and unacceptable that we would put our passengers in this kind of situation,” he said. “Can you be confident in light of what you’ve seen that these are safe?”

Kirschbaum said Muni is working to solve its train issues even now, and would come back to the supervisors — and the public — with answers.

Below, this internal Muni map shows all trains in service — and not in service — at SFMTA’s Muni Metro East Rail Yard.


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Braking problems putting Muni’s new trains out of commission

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