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14 Shared Use of Railroad Infrastructure with Noncompliant Public Transit Rail Vehicles: A Practitioner's Guide All work was reviewed by the A-27 Panel: Submission of each of the 13 Task Reports to A-27 Panel for review and comment. Each report was sub- mitted as a draft. The Panel members provided comments that were forwarded to the team. The revised Task report was then resubmitted to the A-27 Panel. Panel meetings. The team met with the Panel members on two occasions, to review progress, brief them on available results or issues requiring guidance and to receive direct comments regarding the Task reports. This report reflects those efforts; however, the insights and conclusions are tempered by first- hand experience gleaned from preparation of an FRA Waiver Petition and direct involvement in all aspects of initiating a shared-track operation. Shared-Track--The Operating Environment Currently mixed operations of light rail transit vehicles and conventional freight trains are permitted only under restrictions established by the FRA using the principle of "temporal sepa- ration". Ironically this is how railroads were run back in the early to mid-1800s, before the advent of electrical train control systems. Characteristics of a Shared-Track Corridor A route that reflects most of these general physical or operating characteristics is an attractive candidate for shared use: It is a light density short line used by freight. The freight operation is a small, relatively self- contained operation with limited volumes of traffic, not a far-flung system with connected facilities and traffic in many states and the technical systems and infrastructure to support such an enterprise; Freight traffic is a mixture of short through trains and some switching operations, with some delivery schedule flexibility; Highway/rail grade crossings and industrial or customer freight sidings are present; The route is presently dark territory or has very few signals, and no centralized traffic control (CTC), with simple radio communications between a freight dispatcher and train or MOW crews; The route is end-to-end and has the potential for downtown distribution via exclusive light rail passenger car street running on at least one end; or possibly an intermediate street run- ning segment; Dedicated passenger and freight crews familiar with route physical characteristics are available; Light rail passenger car performance is the same for all cars and consists do not exceed two cars. The passenger equipment is "captive" and dedicated; Passenger service frequency is no greater than 10-minute headways in peak and 30 minutes in off-peak. Freight operations may have an exclusive operating window for 4 to 6 hours after midnight and before the start of the morning rush hour; Relatively low top speeds (not exceeding 60 MPH) are feasible for passenger equipment with limited requirements for civil speed enforcement; reduced freight speeds possible; Existing operating rule books, practices, and procedures are tailored to freight operations; Upgrades to the infrastructure such as improved track, train control, C&C system, stations, and the like, suitable for a light rail passenger operation, are feasible. Presence of the characteristics outlined above can guide a planner towards a potential shared track project. However, multiple or extreme deviations from these characteristics may justify closer scrutiny of the plan, or render a true shared-track operation infeasible.