 On 16 December 1999 , NSB confirmed the option for another six Class 73 trains , costing NOK 680 million , for use on the Østfold Line . On 7 January 2000 , the trains were put into service on the Dovre Line between Oslo and Trondheim , and on the Sørland Line between Kristiansand and Stavanger . The travel time from Trondheim to Oslo was 5 hours and 46 minutes . In an independent marketing survey , Signatur customers were more satisfied than the customers for the two main airlines , Braathens and Scandinavian Airlines , but the train service had a lower reputation than the airlines . By May , the number of passengers on the Sørland Line had fallen by 10 percent . The reason was the limited capacity during the weekends ; while NSB had previously run trains with 400 to 500 seats , Class 73 had considerably less capacity . Additional services were introduced on the Dovre Line from 11 June 2000 , while the introduction on the Bergen Line was delayed because the infrastructure upgrades on the Bergen Line were not yet completed . 
