Improving Rail Vehicle Reliability by Performing Component Overhauls at Los Angeles County Metropolitan Transportation Authority

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Improving Rail Vehicle Reliability by Performing Component Overhauls at Los Angeles County Metropolitan Transportation Authority


This study evaluates the effectiveness of component overhauls on vehicle and component reliability by utilizing maintenance records from the Los Angeles County Metropolitan Transportation Authority (LACMTA or Metro). Rail transportation authorities perform component overhauls, a type of schedule-based maintenance at prescribed intervals, to prevent vehicle and component failures. Preventing component failures through component overhauls can help agencies avoid delays caused by component failures, potential safety hazards, and overall reduced vehicle reliability (which negatively impacts transit agencies and their customers). Component overhaul programs aim to maintain and improve reliability, but they can be more expensive and labor intensive than other maintenance approaches such as reliability-centered maintenance (RCM) or condition-based maintenance (CBM). Thus, it is important to evaluate Metro’s current component overhaul programs to determine if they are effectively reducing vehicle and component failures. This study utilized existing LA Metro maintenance records to calculate the reliability of the coupler and friction brake systems of three rail fleets. Results show that component overhauls improved vehicle reliability by some metrics but unexpectedly reduced reliability in other cases. Results recommend potential improvements to the component overhaul process, but further research is needed to fully understand the impacts of component overhaul on vehicle reliability, transit, and communities. 



Aaron Disman is Senior Manager of LA Metro’s Transit Vehicle Engineering department. He received his B.S. in Mechanical Engineering from UC Santa Barbara in 2002, MS in Transportation Management from San José State University in 2022, and is a licensed Professional Engineer. Aaron’s professional experience spans transportation, environmental engineering, and manufacturing. His work at Metro primarily focuses on providing engineering support to the rail vehicle and bus maintenance departments. Aaron's work on this project received the AECOM award for an Outstanding Capstone on Transportation Operations Management.

December 2022
Light rail vehicles



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