AAR DESIGNATING LETTERS AND DEFINITIONS
Class B-Passenger Type
Class X-Boxcar Type
B-Box Express. A boxcar constructed and equipped to render
XM-Box. A house car for general service and especially for
it suitable for passenger train service, having suitable side
lading requiring protection from the weather, with or without
doors, with or without end doors or windows.
lading tie anchors, and equipped with side, or side and end
Class L-Special Car Type
LB-A house car with high sliding doors at center, both sides.
XC-A house car having individual compartments with a
Balance of sides, approximately the lower half, provided each
multiplicity of side doors and suitable for general commodity
side with two or more doors hinged at top to open outward
with suitable locks at bottom.
XL-Loader Equipped. A house car similar in design to XM,
LC-A house car with side doors and roof hatches. May be
either fully or partially lined with steel perforated side walls or
equipped with end doors.
equipped with interior side rails or stanchions and crossbar
members, for securement of certain types of lading and/or
LRC-A house car heavily insulated, with or without ventilation,
permanently attached movable bulkheads. Cars built or
with or without hatches, with or without gravity conveyors for
rebuilt since 1966 must have a minimum of four side rails.
loading or unloading. May have cross partitions forming
compartments. Designed primarily for the transportation of
XP-A house car similar in design to XM but' specially
solid carbon dioxide.
equipped for specific commodity and not suitable for
miscellaneous commodity lading.
LU-An enclosed car with roof, having a special metal beam of
heavy design at top of each side to support a series of
XR-Auto Device Car. A house car similar in design to XM
retractable overhead side door and their appurtenances, or
boxcar, either lined or unlined, with side or side and end doors
other types of doors, running substantially the length of car,
and equipped with loading racks and/or floor tubes with
which beams also support roof details. Car may be equipped
tiedown chains for loading setup automobiles and trucks.
with special loading devices or racks for handling various
XT-A house car with or without doors and either metal lined or
enclosing one or more tanks.