Many times on stored Conrail freight cars, either an "RS-41" or "RS-42" is crudely stenciled on the sides of the car. Over the years it has been suggested that this stands for "Retired / Scrap" however, there is a much more important explanation to what the letters and numbers actually mean!
The RS stands for "Repair Status". It took over 40 hours of repairs to put a car in this status so they used the number 41. Then they had an alpha system that should have been stenciled on the old Conrail cars. Two of them were;
RS-41G = 40 to 74 man hours
RS-41N = 75 to 99 man hours
It was used to classify cars for a program at Hollidaysburg. RS-42 was used for cabooses only, while RS-41 was for all Conrail owned freight cars.
This Conrail fact has been confirmed by Conrail previously, as well as Norfolk Southern.