Another big challenge with the English language includes our use of different words for similar things.  Here it is Class and Type.

Chris quoted from a document in an earlier post.  MCB, later ARA and then ICC specifications differentiated between “Classes” of tank cars.

ACF used the word “Type” together with a year to designate significant design changes in its tank cars, although construction of Types often overlapped.  So, the F&C kit is an MCB/ARA Class II AND an ACF Type 11, while the P2k car is a an ARA Class III and an ACF Type 21.

To further challenge us, UTLX referred to their designs as “Classes.”  So, their Class X and Class V cars were MCB/ARA Class II.  To meet the ARA Class III specs (to which they were a party in the creation) UTLX created their Class X-3 cars, whose design evolved over the next 20 or so years.

I am not sure whether the Type+Year designations we use for General American tank car designs come from the company or us modelers.

Steve Hile