1932 ARA Box Car Roster
The introduction of the 1932 ARA Box Car can be looked upon as a watershed event in the history of freight car design. Alone, it did not receive the recognition, in terms of orders, that its descendants, the 1937 AAR design, the Modified 1937 AAR design and the Postwar AAR design, did. However, it can be viewed as one of the most successful designs ever when the sum total of its progeny are viewed.
The '32 ARA ushered in the use of tabbed side sills with a portion of the structural integrity of the car being in the sides, rather than the underframe. The ARA underframe used on the '32 car became the standard for the subsequent iternations of the design, with little variation. However, the biggest outcome of the introduction of this car, was the mass adoption among many different buyers that it created. While it had more variation among components than its offspring, it helped create the new circumstances whereby many railroads could buy a car of the same basic design, rather than each road having its own mechanical department's design.
A couple of notes about the design, courtesy of Jeff Koeller and Ed Hawkins:
1. The inside heights shown varied, but the different IH dimensions were due to variations in the thickness of the floor. The external car body dimensions for the design were the same.
2. The ARA "standard" inside width dimension was 8'-9". However the BAR and Soo Line cars were slightly wider at 9'-2". While these cars had the general height of the 1932 ARA cars, they had the width of the 1937 AAR cars. As such, the BAR and Soo Line cars should be classified as "transitional cars."