Class 'F' - Flat Car Type

FA - Flat car specifically equipped with superstructure or containers for transporting set-up vehicles, not suitable for miscellaneous commodities.

FB - Bulkhead flat cars. Equipped with fixed or permanently attached movable bulkheads or ends a minimum of three feet in height and flat floor for general commodity loading.

FC - Flat cars, specifically equipped to carry trailers, containers, chassis, or removable trailer bodies for the transportation of freight in TOFC/COFC service.

FCA - Flat car, articulated multi-unit, specially equipped to carry trailers, containers, chassis, or removable trailer bodies for transportation of freight in TOFC/COFC service.

FD - Depressed center flat car of special construction having the portion of floor extending between trucks depressed provide necessary overhead clearance for lading.

FL - Flat logging car or truck. This is either an ordinary flat car, or car consisting of two trucks fitted with cross supports over truck bolsters; the trucks connected by a skeleton or flexible frame and logs loaded lengthwise on cross supports.

FM - Ordinary flat car for general service. This car has flooring laid over sills and without sides or ends.

FW - Flat car with hole to enable lading to be lowered due to clearance limits.

Note: Where cars are specially modified or equipped for handling particular commodities, the letter "S" must be affixed to the applicable designating letters. This would not apply to cars with FA, FD, FL, OR FW designation.

Class 'G' - Gondola Car Type

GA - Open top car, having fixed sides and ends and drop bottom, consisting of doors hinged crosswise of car, to dump between rails.

GB - Open top car, having fixed sides, fixed or drop ends and solid bottom.

GD - Open top car, having fixed or drop ends, solid bottom, and sides equipped with doors for dumping.

GH - Open top car, having fixed sides, drop ends and drop bottom, consisting of doors hinged at center sills to dump outside of rails.

GS - Open top car, having fixed sides and ends and drop bottom, consisting of doors hinged at center sills or side sills to dump outside and/or inside of rails.

GT - Open top car, having high fixed sides and fixed or hinged ends and solid bottom, suitable for unloading on dumping machines only.

GW - Open top well-hole car for transportation of special commodities. A solid bottom car with fixed sides and ends, having one or more openings or depressions provided in floor, permitting the lading to be lowered in order to obtain overhead clearance.

Note 1: Where cars are specially modified or equipped for handling particular commodities, the letter "S" must be affixed to the applicable designating letters.

Note 2: If any of these gondola cars are equipped with a roof for protection of contents the letter "R" must be affixed to the regular symbol to designate its special class of service.

Class 'H' - Hopper Car Type

HFA - Open top self-clearing car, having fixed sides and ends and bottom consisting of divided hoppers at center with doors hinged lengthwise, dumping outside and/or inside of rail; also one divided hopper each end, extending from end of car to bolster with doors hinged lengthwise of car and dumping outside of rails.

HK - Open top self-clearing car, having fixed sides and ends and bottom consisting of two or more divided hoppers dumping outside and/or inside of rails. (Includes former designation 'HD').

HM - Open top self-clearing car, having fixed sides and ends and bottom consisting of two divided hoppers with doors hinged crosswise of car and dumping between rails.

HMA - Open top self-clearing car, having fixed sides and ends and bottom consisting of two divided hoppers with doors hinged lengthwise of car and dumping between rails.

HT - Open top self-clearing car, having fixed sides and ends and bottom consisting of three or more divided hoppers with doors hinged crosswise of car and dumping between rails.

HTA - Open top self-clearing car, having fixed sides and ends and bottom consisting of three or more divided hoppers with doors hinged lengthwise of car and dumping between rails.

Note 1: Where cars are specially modified or equipped for handling particular commodities, the letter "S" must be affixed to the applicable designating letters.

Note 2: If any of these gondola cars are equipped with a roof for protection of contents the letter "R" must be affixed to the regular symbol to designate its special class of service.

Class 'L' - Special Car Types

LC - Box car with side doors and roof hatches. May be equipped with end doors.

LF - Flat car equipped to handle one or more demountable containers for the transportation of commodities not under refrigeration.

Note: Not applicable to flat cars designed to handle containers in TOFC/COFC service or containers handling setup vehicles.

LG - Gondola car equipped to handle one or more demountable containers for the transportation of commodities not under refrigeration.

LM - A car equipped with one or more permanently enclosed tanks or containers, provided with one or more openings for lading and equipped for pneumatic or gravity unloading. Car is suitable for handling certain dry powdered or granular commodities, and also low viscosity, non-dangerous liquid commodities.

LO - A permanently enclosed car, other than a box car, regardless of exterior or interior shape, for handling bulk commodities, with or without insulation and provided with openings for loading through top or sides with with weather-tight covers or doors. Car may be provided with one or more bottom openings for unloading, with tight fitting covers, doors, valves, or tight fitting slide or gate to prevent leakage of lading. Car may be provided with facilities for discharge of lading through openings in top or sides and may have one or more compartments. Mechanical or other means may be provided within car to expedite loading or unloading. (All covered hoppers).

LP - Open-top car having solid bottom and fixed ends equipped with sloping floor or longitudinal floor risers or sidestakes for the handling of pulpwood and not suitable for general commodity loading.

LS - A car of special construction having two separable interlocking units which form car body. Units may be separated and load interposed between and locked in place to form a complete transportation unit. (Schnable car).

LU - An enclosed car with roof, having a special metal beam of heavy design at top of each side to support a series of retractable overhead side doors and their appurtenances, or other types of doors, running substantially the length of car, which beams also support the roof details. Car may be equipped with special loading devices or racks for handling various commodities. (This designation was created for Southern Railway All-Door Box Cars...)

Class 'N' - Caboose Car Type

NE - All cabooses.

Class 'R' - Refrigerator Car Types

RB - Bunkerless refrigerator car with or without ventilating devices and with or without device for attaching portable heaters. Constructed with insulation in sides, ends, floor and roof to meet maximum UA factor requirement of 250 BTU/F/hour for 50 foot cars and 300 BTU/F/Hour for 60 foot cars. Effective for cars ordered new after March 1, 1984.

RBL - Car similar in construction to 'RB' type car, but equipped in addition with adjustable loading or stowing device.

Note: Cars equipped with interior side rails only, built new, rebuilt or reclassified on and after January 1, 1966, in order to qualify for the 'RBL' designation, shall have a minimum of four (4) usable side rails on each wall of car, each extending from doorway to approximately four (4) feet from end of car.

RP - Mechanical Refrigerator car equipped with or without means of ventilation and provided with apparatus for furnishing protection against heat and/or cold. Apparatus operated by power other than from the car axle(s).

RPB - Mechanical Refrigerator car. Similar to 'RP' type car but designed primarily for use in bulk potato or similar type loading as cars are equipped with interior slope sheets and conveyors and/or equipment for mechanical loading and unloading.

RPC - Mechanical Refrigerator car similar in design to an 'RP' but equipped with permanently affixed container(s).

RPL - Mechanical Refrigerator. Similar to 'RP' but equipped in addition with adjustable loading or stowing device.

RS - Bunker Refrigerator car equipped with ice bunkers. Designed primarily for use of chunk ice and with or without means of ventilation.

Class 'S' - Stock Car Type

SC - Car for transportation of livestock equipped with roof, slatted sides and side doors and double deck. With or without feed and water troughs.

SM - Car for transportation of livestock equipped with roof, slatted sides and side doors, and single deck. With or without feed and water troughs.

ST - Car for transportation of livestock equipped with roof, slatted sides and side doors, and fixed triple deck. With or without feed and water troughs.

Class 'T' - Tank Car Type

T - Tank Car. Tank car means any car which is used only for the transportation of liquids, liquefied gases, compressed gases, or solids that are liquefied prior to unloading. Car may be without underframe if container serving as superstructure is designed to serve as underframe. If car has underframe, it must be designed only for the carriage of one of more enclosed containers (with or without compartments) that form the superstructure and are integral parts of the car. All such containers must be securely attached to the underframe when offered for transportation but may have demountable features. Before any car can be considered a tank car hereunder, the design of all such containers thereon must have been approved 1) by the AAR Committee on Tank Cars as having met all applicable AAR specifications and requirements and 2) by said Committee or, in appropriate cases, the Department of Transportation, as having met all applicable specifications and requirements of Subpart I of the Regulations for Transportation of Explosives and Other Dangerous Articles.

Class 'X' - Box Car Type

XM - Box car for general service equipped with side or side and end doors.

XF - Non-insulated box car similar in design to 'XM', designed and specifically prepared with a U.S. Food and Drug Administration approved white epoxy or other comparable white coating to seal interior walls, doors, and ends, and provide a smooth durable surface to prevent contamination.

XL - Loader Equipped. Box car similar in design to 'XM', with steel perforated side walls or equipped with interior side rails for securement of certain types of lading and/or permanently attached movable bulkheads.

Note: Cars equipped with interior side rails only, built new, rebuilt or reclassified on and after January 1, 1966, in order to qualify for the 'XL' designation, shall have a minimum of four (4) usable side rails on each wall of car, each extending from doorway to approximately four (4) feet from end of car, plus facilities in doorway to accommodate doorway members. The facilities in the doorway are not required in cars equipped with plug type doors.

XP - Box car similar in design to 'XM', but which is specially equipped, designed, and/or structurally suitable for a specific commodity loading; except box cars dedicated to the transportation of commodities in paragraph A, Rule 97, AAR Interchange Rules, must be designated, 'XP'.

Note 1: The specific lading for which intended must be included in the description column in The Official Railway Equipment Register.

Note 2: Box cars having an 'XM' designation being changed to 'XP' must be reported to the Secretary, Transportation Division, ten (10) days prior to restenciling. XT - Box car with or without doors either metal lined or enclosing one or more tanks.

Note: When any of the foregoing Class 'X' cars are insulated, the letter 'I' should be added to the designation.