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The EMD F7 was a Diesel-electric locomotive produced between February 1949 and December 1953 by the Electro-Motive Division of General Motors (EMD) and General Motors Diesel (GMD). Although originally promoted by EMD as a freight-hauling unit, the F7 was also used in passenger service hauling such trains as the Santa Fe Railway's ''Super Chief and El Capitan''. ==History== The F7 was the fourth model in GM-EMD's successful line of F unit locomotives, and by far the best-selling cab unit of all time. In fact, more F7's were built than all other F units combined. It succeeded the F3 model in GM-EMD's F unit sequence, and was replaced in turn by the F9. Final assembly was at GM-EMD's La Grange, Illinois plant or GMD's London, Ontario facility. The F7 differed from the F3, primarily in internal equipment (mostly electrical) and some external features. Its continuous tractive effort rating was 20% higher (e.g. for an F7 with gearing, compared to for an F3 with the same gearing. A total of 2,366 cab-equipped lead A units and 1,483 cabless-booster or B units were built. (Note: the B unit is often referred to as an "F7B", whereas the A unit is simply an "F7".) Many F7s remained in service for decades, as railroads found them economical to operate and maintain. However, the locomotive was not very popular with yard crews who operated them in switching service because they were difficult to mount and dismount, and it was also nearly impossible for the engineer to see hand signals from a ground crew without leaning way outside the window. As most of these engines were bought and operated before two-way radio became standard on most American railroads, this was a major point of contention. In later years, with the advent of the “road switchers” such as the EMD GP7, F units were primarily used in “through freight” and “unit train” service where there was very little or no switching to be done on line of road. 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「EMD F7」の詳細全文を読む スポンサード リンク
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