1.5. RAILWAY TERMS
The definitions of railway terms used by TRS personnel are
sometimes different from those used by the AAR, commercial
railroaders, and most laymen. The following terms and definitions
are pertinent to a clear understanding of this text.
Current of trafficmovement of trains on a main track, in one
direction, specified by the rules. On a singletrack line
where as many trains must run one way as the other, the
current of traffic is in both directions. On a doubleor
multipletrack line, the direction of each track is
designated and has a current of traffic established for it
according to the direction of train movements on it. For
example, suppose you have a doubletrack line connecting
Pittsburgh with Philadelphia, Pennsylvania. One track would
be for eastbound traffic and the other for westbound.
Divisionportion of railroad assigned to the supervision of a
superintendent. In the TRS, the transportation railway
battalion (TRB) commander is the railway superintendent, and
the battalion under his command is normally assigned a rail
division from 145 to 241 kilometers (90 to 150 miles) in
length.
Engine (as used in TM 55200 means railway locomotive) (l) a
unit propelled by any form of energy, or (2) a combination of
such units, other than steam, operated from a single control,
used in train or yard service. The TRS normally uses diesel
electric locomotives; however, it uses any railroads and any
equipment found in a theater including steam and electric
locomotives and electrified rail lines.
Extra traintrain not authorized by a timetable schedule. It
may be designated: (1) extra, for any extra train except
passenger extra or work extra; (2) passenger extra, for
passenger train extra; (3) work extra, for work train extra.
Extra trains carry white classification signals on the front
of the locomotive and are always authorized by train order.
Fixed signalsignal with a fixed location for regulating
railroad traffic.
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