When were double stack container cars introduced?
I don’t know when they were introduced, but I believe SP started useing them on the Sunset in 1983.
I believe that the earliest ones came into use about 1979 or 1980.
For the definitive answer, see David J. DeBoer’s 1992 book, Piggyback and Containers: A History of Rail Intermodal on Americas’s Steel Highway (Golden West Books, ISBN: 0870951084).
- PDN.
From an article in MR Oct 1983 issue:
Southern Pacific and American Car and Foundry started developing the double stack idea and built a single unit test car, SP513300 in 1977. An articulated 3 unit car followed a couple years later. This was followed by 41 of the five unit cars, built through 1981. These were designed to carry 35 and 40 foot containers. Because of the end bulkheads, it couldn’t carry a longer container, even on the upper position.
The SP513300 is currently on display at the California State Railroad Museum.