Tim, I suspect this is a narrow-gauge car in Newfoundland service.  As you may recall, during the Second World War, Britain traded bases for old destroyers, including some in Newfoundland (then a British colony).  Since this car is lettered for the U.S. Air Force, I'm assuming that we are looking at a photo taken sometime circa or after 1947, and likely in aviation gasoline service or possibly jet fuel.

I believe this car was likely built by Canadian Car & Foundry, whose standard cars seem to have a lot in common with AC&F cars.  I presume that they built AC&F frames under licence, but don't know this for a fact.