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BART: Testing equipment wire caused crash, not car or operators
Author: J
Date: 04-29-2016 - 05:35
So the Fleet of the Future has hydraulic brakes?
Excerpt:
According to Bay Area Rapid Transit (BART) officials, there was no malfunction of the train car and no operator error April 22, 2016 when a car being used for operator training on a Hayward test track ran into a sand box after a brake issue.
The crux of what happened: A wire running from testing equipment to the train car shorted out when pinched in a cabinet door. This caused the auxiliary power supply to short to ground and shut down. This is the system that supplies power to the pump that replenishes the brake fluid.
As a result, once the fluid in the accumulator had been expended it was not replenished. The electric brakes slowed the car to 5mph; the friction brakes did not have adequate fluid to complete the stop and the car rolled into the sand box. This failure can only occur with a single car (which does not happen in passenger service) because in a train the other cars in the train would carry through the braking process.
“The incident was caused by a pinched wire connecting the car to test equipment. It was not due to malfunction of the car or actions of the operator,” said New Car Program Manager John Garnham.
“We look at it as a learning experience,” Garnham said. “We’re going to implement some software changes to provide more protection for single car moves and update procedures to protect against this type of failure in the future.”
Railway Age
Excerpt:
According to Bay Area Rapid Transit (BART) officials, there was no malfunction of the train car and no operator error April 22, 2016 when a car being used for operator training on a Hayward test track ran into a sand box after a brake issue.
The crux of what happened: A wire running from testing equipment to the train car shorted out when pinched in a cabinet door. This caused the auxiliary power supply to short to ground and shut down. This is the system that supplies power to the pump that replenishes the brake fluid.
As a result, once the fluid in the accumulator had been expended it was not replenished. The electric brakes slowed the car to 5mph; the friction brakes did not have adequate fluid to complete the stop and the car rolled into the sand box. This failure can only occur with a single car (which does not happen in passenger service) because in a train the other cars in the train would carry through the braking process.
“The incident was caused by a pinched wire connecting the car to test equipment. It was not due to malfunction of the car or actions of the operator,” said New Car Program Manager John Garnham.
“We look at it as a learning experience,” Garnham said. “We’re going to implement some software changes to provide more protection for single car moves and update procedures to protect against this type of failure in the future.”
Railway Age
BART: Testing equipment wire caused crash, not car or operators