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1939 World's Fair RailroadThe City Of New York, Acting by the
Board of Transportation About the Contract DrawingsThe contract for furnishing the block signal system defines all the equipment to be installed and tested for a continuous, seamless signal system from the 71st-Continental Avenues Station through Jamaica Yard to the World's Fair Terminal. The signal system consists of automatic and approach signals, home signals, train stops, switch machines, track circuits, relay cases, relay room and tower at the World's Fair Terminal and changes to the existing interlocking machine and model board at Jamaica Yard. The contract drawing book comprises 99 pages and includes all drawings required to install the entire signal and telephone system, including all circuit changes required. The contract is very specific in its call for signal equipment manufactured and installed by the Union Switch and Signal Company: for example, the switch machines and train stop mechanisms are all to be operated pneumatically. The contract drawings include General Signal Arrangements, which are single-line plans illustrating the track layout for the entire contract, including the control lines (defining the extent of unoccupied track to clear each signal), and Location Plans, which are double-line track plans showing all track equipment, including indicating which of the two running rails is the signal track circuit signal rail (heavy line) and which is the return (negative) rail for the propulsion current (to the substation). Also included are typical layouts of automatic, approach, and home signals, and a plan for the changes to be made to the Jamaica Yard tower model board for new Contact Rail Illuminated Indications. Please see Understanding NYC Subway Single-Line Signal Diagrams for information on the notation used in the General Signal Arrangements. Understanding the ContractThe Jamaica Yard lead tracks, which are designated D5 and D6, start on the lower level of 75th Avenue Station on the Queens Line. Before the World's Fair Railroad was installed, they continued over the Grand Central Parkway into Jamaica Yard, where track D5 ended at a bumper post before the yard storage tracks and track D6 forked into yard storage tracks 30 through 33. Contract Drawing 7-6 shows the bumper post at the end track D5 removed and extended to the World's Fair Terminal. A turnout switch was installed on the storage ladder tracks to extend track D6 to the World's Fair Terminal. A crossover was installed to connect track D5 to D6. In the Jamaica Yard signals have a maximum (most permissive) signal aspect of yellow. Since track D5 and D6 become mainline tracks under the contract, all these signals are to be augmented to display a maximum aspect of green, for distant control. This is shown in Contract Drawing 7-6. The curve in the subway section approaching the Jamaica Yard, which until the advent of the World's Fair Terminal was only used for yard moves, required additional safety for the mainline traffic now destined to that terminal. To that end, "two-shot" Grade Time (GT) control was added to the existing signals around the curve on track D6 to enforce an appropriate speed limit. The characteristic S aspect of this type of control was added to signal heads, and new trackside relay cases were installed, modifying a total of seven signals. Contract Drawings 7-2, 7-5 and 7-6 show the addition of the GT signaling. With the installation of the additional turnout switch, crossover, GT signaling and extenuation of tracks D5 and D6 changes where required to the Jamaica Yard Tower Union Switch & Signal Model 14 mechanical interlocking machine and its model board, as shown on Contract Drawings 7-79 and 7-80. Tracks D5 and D6 continue past the Jamaica Yard on their way to the World's Fair Terminal Station. Contract Drawings 7-3, 7-4, 7-7, 7-8, 7-9 and 7-10 show the tracks D5 and D6 and a middle track called track D7 before the World's Fair Terminal. Track D7 was used for storage of extra trains when the crowds at the World's Fair were heavy. The extra trains were brought out of the storage tracks to the platform tracks. After the World's FairAfter the World's Fair, the terminal station, tracks D5, D6 and D7 were removed completely, and Jamaica Yard was reconfigured to its original layout. The seven GT signals remain in service today. Contract Drawings
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