There were numereous cars that were marked as "assigned service" and where they
were to be returned when empty. It would be hard to call them unit trains cars.
I remember the Coleman-Port Moody cars, but there were many other of all shapes
and sizes. It was one way to try to guarantee car supply for regular shippers
and because they would always carry the same cargo they did not have to be
thoroughly cleaned every time they were emptied.
Speaking of assigned service, when we were doing the EABS tests we had one car
go bad order and it had to be cut out of the train. When it was fixed and
returned to service it did not get put back in the EABS train set. We had to
chase it all over western Canada for several weeks before we could arrange to
have it set out and put where it belonged. This was particularly annoying as
there was only one EABS equipped train set and that train set was a fixed
length and was then one car short and you could not use a non-EABS equipped car
as a replacement.
DEC
In the 1960s there were dedicated cars painted "Coleman-Port Moody" run as unit
trains or at least as big blocks. They were pictured in the annual report about
1967.
Don Thomas
I always thought the "Unit Train" concept required the train to stay together
throughout one or more cycles. On CPR they started with the Fording coal
trains in 1969 or 1970. No switching was involved at either end; the train
set returned empty to the mine unchanged for another load. Other roads may
have had earlier examples. <snip>
