Editing EMD FT (section)

== Design and production ==
The first units produced for a customer were built in December 1940 and January 1941 for the [[Atchison, Topeka and Santa Fe Railway]] and numbered the 100 set. These were the first diesel-electric locomotives ever produced with [[dynamic braking]], a system developed at the insistence of the railroad and with its assistance. Initially the four-unit, coupler-equipped set featured two booster units between two cab units in the manner of the demonstrator set. The Brotherhoods of Locomotive Engineers and Firemen, however, insisted that the two cabs required two crews, so the railway had EMD produce extra boosters, and renumbered its earliest sets into four unit sets with one cab unit and three boosters. Negotiation with the unions soon rectified the situation, but as the road's earliest units were geared for higher speeds than subsequent units, these sets continued to be composed of one FTA cab unit and three FTB boosters. This is why the road had ten more FTB booster units than FTA cab units.<ref>Iron Horses of the Santa Fe Trail, E.D. Worley, Southwest Railroad Historical Society 1965, Library of Congress 75-39813</ref> The original A-B-B-A demonstrator set was sold to the [[Southern Railway (U.S.)|Southern Railway]].

The FT was equipped with the [[EMD 567]] medium-speed two-stroke cycle Diesel engine, along with its many successors.

FTs were generally marketed as semi-permanently coupled A-B sets (a lead unit and a cabless booster connected by a solid drawbar) making a single locomotive of {{convert|2700|hp|abbr=on}}. Many railroads used pairs of these sets back to back to make up a four-unit A-B-B-A locomotive rated at {{convert|5400|hp|abbr=on}}. Some railroads purchased semi-permanently coupled A-B-A three-unit sets of {{convert|4050|hp|abbr=on}}. All units in a consist could be run from one cab; [[Multiple-unit train control|multiple unit]] (MU) control systems linked the units together. Some roads, like the initial customer [[Atchison, Topeka and Santa Fe Railway|Santa Fe]], ordered all their FTs with regular couplers on both ends of each unit for added flexibility. This package included "hostler" controls for B units, enabling these units to be operated independently of A units for moving within yard limits, and a fifth porthole was provided in the carbody to enable the "hostler" some measure of visibility. Internally, EMD referred to these units as model FS.