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Summary 7 Integrating Technology for Effective Command and Control Freight carriers and passenger operators must be able to communicate when using the same track. This is fundamental to joint operation regardless of the type of railroad equip- ment in service. This capability is relatively easily served by conventional technology, at an acceptable cost. Regardless of the choice and capabilities of train control and communications technolo- gies, these will have to be integrated with Rules and Procedures to complete the frame- work of C&C. Both the freight and passenger operator need to use a unified rulebook and receive movement authority from one control center, preferably the passenger operator. The current variety of vehicle choices necessitates that each new or unique vehicle must be analyzed from a safety perspective, increasing overall system deployment costs. Stan- dardization can facilitate the incorporation of Crash Energy Management (CEM) features by avoiding or limiting the structural and risk analysis necessary for each railcar. Further reduction of the number of standardized vehicle categories and models will contribute to lower unit costs and facilitate acceptance by agencies and regulators. Requirements for Concurrent Shared-Track Operations Under the current North American regulatory framework, each shared-track operation must be approved by a waiver exception. Each such shared-track operation must incorpo- rate measures that are safe, verifiable, and achievable when regulatory exceptions are sought. Detailed engineering or safety criteria allowing routine approval of standard shared-track system designs appear unlikely in the near future. Analysis and research experience to date indicates that shared-track operations that meet the following criteria have an elevated like- lihood of achieving approval in the federal process. 1. Light Density Freight Operation (less than 1.5 million gross tons per annum) 2. Medium Density Transit Operation at Limited Speeds (no more than 20 minutes off peak headway, and at speeds of less than 60 mph) 3. Adoption of Railroad-like Rulebook for Transit Operations 4. Fail-Safe Train Separation Technology for Both Light Passenger Rail Cars and Freight train consists (variance from 49 CFR Parts 234 and 236 must be justified) 5. Common and Shared Communications Network 6. Full FRA Compliance and Reporting, Except: a. Transit Vehicle Design (49 CFR Parts 221, 223, 229, 231, 238, 239) b. Transit Operators are not FRA Engineers (49 CFR 240) c. Minor Variance on Hours of Service (49 CFR 225, 228) Waivers: The waiver process puts the applicant at the whim of authorities that may iden- tify additional requirements due to unforeseen local circumstances or new lessons learned from novel accident scenarios. FRA may require specific risk analyses for the proposed oper- ations. However, planners should be confident that if the proposed operation meets these requirements, the risk of regulatory stall is much reduced. Equipment: Given the disparity in structural capabilities and weights of light passenger rail cars and conventional railroad equipment, the light rail cars cannot be expected to provide pri- mary passive protection in an accident. A dominant role for train control clearly emphasizes crash avoidance over crashworthiness. Command and Control: From the outset the train control system should be designed with concurrent shared-track in mind. This allows the designer to account for high service braking rates of the light passenger rail car and design appropriate block lengths and signal aspects.