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OCR for page 49
Enabling Shared-Track: Technology, Command, and Control 49 2. There is a commonality of maintenance practices, training, documentation, and tooling across multiple users similar to the aviation industry. 3. Standardization contributes to lower vendor prices by creating a larger market, a more constant level of production, and potential for competition. Recommended Vehicle Research The FRA considers the structural capabilities of light passenger rail cars to be the primary deficiency with respect to shared-track operations. Additional research and analysis may alle- viate some of their concerns by providing more technical data to support regulatory evaluations and improve project vehicle design decisions. High value topics that merit further investigation include: 1. Typical braking systems used on light passenger rail car equipment are not incorporated into rolling stock otherwise manufactured for use in the nation's general rail transportation sys- tem. Accordingly, including a detailed explanation of the performance and reliability of track brakes or hydraulically actuated brakes in a waiver petition would enable the FRA to make a more informed decision. These data should include various comparisons of test results with multiple brake systems fully functional and tests with one or more of the systems cut out or malfunctioning. Test results then can be compared to similar data for conventional freight and commuter rail equipment to justify a signal design more appropriate for a shared-track operation. The data could also support a waiver petition for relief from provisions of 49 CFR Part 236 and contribute to the safety case. 2. Support/encourage computer simulation of structural failures caused by various accident and impact scenarios. Even better would be results of a real-world test between a light pas- senger rail car and a freight car or locomotive. Presently this has been performed for conven- tional freight and commuter rail equipment and is contributing to improved CEM designs for passenger rail cars. There is a need for a similar exercise using light passenger rail cars to verify or improve CEM designs. Such a research program would quantify effects of low and high-speed impacts on the car body and interior, and identify the secondary collision effects on passengers. Com- puter analysis and test results would help validate a risk assessment and support a safety case. Applying Technology to Shared-Track Operations-- A Brief Guide Transportation planners and specialists should be familiar with train control systems and appreciate their impacts on safety, operations (both freight and passenger), and capital and oper- ating costs. These systems are a significant contributor to a favorable outcome of an FRA Waiver Petition process and thus affect project viability. Local officials and transit agencies that consider a shared-track project are advised to give the selection of a train control system top priority. 1. Command and Control (C&C) encompasses the train control system, communications net- work, and R&P. C&C provides and enforces movement authority for all rail traffic and is intended to emphasize safety via collision avoidance rather than depending upon vehicle crashworthiness. The system capabilities, relative costs, and performance features help to drive the choices of technology. These selections have a pervasive impact on: Risk assessment and by extension the waiver petition; Costs--capital, operations, and maintenance; and Operational capabilities and limitations of both the freight and passenger services.

OCR for page 49
50 Shared Use of Railroad Infrastructure with Noncompliant Public Transit Rail Vehicles: A Practitioner's Guide 2. A range of technology from conventional through advanced systems can be considered, and risk reduction is available from both traditional and leading edge technology. Appendix 4 provides relative cost comparisons of various train control systems for planning purposes. 3. Effective and reliable communication between freight carriers and passenger operators is relatively easily provided using conventional technology, without incurring excessive or disproportionate costs. 4. Despite the C&C safety features, the FRA also will scrutinize the vehicle data for crash- worthiness capabilities and other regulatory features. Near compliance to the extent possible should include: Structural elements and features that manage crash energy and afford some protection for passengers in the secondary collision (passengers impacting elements of the car interior) that would follow an impact; Lights and markers that look like a rail vehicle to highway vehicle operators at grade crossings; Window glazing on passenger railcars (both forward ends of bidirectional railcars, side windows). Control of movement authority is the key to safety and regulatory compliance. C&C and vehi- cle choices can enhance the safety case, which in turn is presented in the FRA waiver petition.