In a message dated 12/21/00 12:58:47 PM Pacific Standard Time, nehrij@...
<< Dick - A wine car should be RB, the "B" being for beverage or beer, but
that's not a car with an internal tank. "TW" would be from the Tank
designation, with "W" meaning a wood tank, like a vinegar or pickle car.
(Meaning these didn't get the stainless steel or enameled tanks such as used
in GPEX milk cars and Chateau Martin cars.) >>
"TW" was the correct letter designation for the PFE refrigerator cars when
sold and converted to wine service (circa 1933-35). During 1935 the AAR
clarified, and/or added to, its list of M.C.B. designations for tank
cars--the "TW" designation read; A car equipped with one or more lined or
unlined wooden tanks or tubs. Note, "tank" car is not specified.
Modifications were made to this designation both in 1936 and in 1940. The
1940 description read; A car equipped with one or more wooden tanks, or, one
or more metal tubs. Such tanks or tubs may be lined. Car is sometimes
equipped with a roof.
By the 1950s the "TW" designation was greatly simplified to read; Tank car
equipped with one or more wooden containers.