Much has been done to bring about uniformity of performance in the North American light rail transit systems. Yet, a lot remains to be done, as there still remain differences between individual vehicles due to manufacturing tolerance and variations in maintenance. Component failures cause major effects to the overall performance of the light rail system and also to the environment and safety. They also cause an increase in downtime cost and waste limited maintenance resources. Repetitive failures can be accredited to factors that are within supervisory control. What is required is zero tolerance towards component failures, and cooperation and coordination between agencies and supply chain partners.
Thankfully, automation largely encourages teamwork and communication across various departments and can be used as a success story to be modeled. The light rail transit organizations have to bring in preventive and proactive maintenance programs to achieve reliability excellence and thereby ensure continued growth in key measures of performance.
With light rail networks getting busier and faster, there is considerable pressure exerted on the existing infrastructure to deliver; hence, there is an urgent need for increased inspection and proactive maintenance of light rail assets. According to Dave Staples, proactive maintenance programs “…usually include predictive maintenance…root-cause failure analysis and the development of key performance indicators.”[1] Proactive maintenance is usually combined with online monitoring and inspection. Over the last decade, numerous decision support systems have been developed to assist the management of light rail transit systems. Rail decision support systems cater to rail and track assets separately, though over the years, considerable efforts have been made to assimilate both. An integrated decision support system would analyze and correct repeated failures, and optimize the time and resources.
Light rail operators too, have to play a larger role in efforts to enhance reliability and reduce repeated failures. Alexandre Sautter in his thesis, ‘The role of the operator in European light rail projects’ has stated, “If the operator is chosen as operability champion, they should have the following role: they must participate at the steering committee level in all decisions concerning the vehicles, the tracks and components and the stops and surroundings.” Other methods such as the Operator-Driven Reliability (ODR) program can also be introduced to optimize the operator’s experience. Operator involvement in the overall performance of a fleet is key as these professionals know the vehicles operating characteristics and leaving them out of the reliability improvement equation would be a mistake.
Light rail transit systems are constantly aiming towards higher speed and carrying capacity. These aims contribute towards the need for increased inspection and higher maintenance of rail assets. Equipment that significantly impacts process operation, or lead to serious environmental or safety problems, are termed critical equipment. Wheelset and rolling stock failures could be minimized by a combination of online monitoring and adequate inspection during production and maintenance. A proactive maintenance policy has to be applied to critical light rail transit equipment to maximize safety efficiency. Similarly, predictive maintenance or condition maintenance allows corrective action before a breakdown. According to Thomas F Brady, “[b]enefits of predictive maintenance may include savings accumulated through full use of critical components, decreased system downtime, and a reduced store of replacement parts.”[2]
Operations planning should ensure that equipment failures are managed with the least disruption. A light rail transit system underperforming due to operator performance is no different from a transit system underperforming due to equipment failure. In that sense, failure analysis serves a positive purpose—to prevent further failures. Failures can be understood intuitively but the underlying conceptual principles are more often misunderstood or completely ignored. Failure analysis bestows all failures to human errors and thus classifies them into three general types.
These are
· Errors of knowledge
· Errors of performance (which might be caused by negligence), or
· Errors of intent (which may come down budgeting)[3]
A P Lezela and I Flynn in their analysis, ‘Maintenance free-total reliability–why not?’[4] define zero failure as a prerequisite for zero maintenance. They have an interesting formula towards failure and maintenance, which is:
Tolerance of failure = more maintenance = yet more failures
Intolerance of failure = less maintenance = fewer failures
An organization which is able to incorporate newer technologies will best manage the competition and yet provide higher service overall. It is therefore important to understand the value of reports and Key Performance Indicators (KPIs). KPIs allow managers to enhance their efficiency by gauging the effectiveness of their organization and identifying problems early.
An asset and service management approach would help meet the current industry issues. With the management of critical assets, light rail agencies could improve the uptime of critical revenue-generating assets; reduce the number of service related delays thus increasing the mean distance between failures; reduce the costs of acquiring, maintaining, and disposing of such assets; and, above all, help increase the value to the public.
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