 Regular operation with electric locomotives was introduced on 25 November 1944 . To begin with , Class 64 railcars were used . NSB had originally planned to use electric multiple units , but changed the plans during the war and instead decided to use locomotives and cars . The Class 64 trains remained in service on the Flåm Line until May 1947 . They were normally used on the Hardanger Line , but were regularly taken back into use on the Flåm Line when the traffic was at its lowest . 
