The feasibility study has suggested that a passenger count of 5000 per day per line could be expected if rail is competitive with air travel. This is much lower than German or French high-speed lines, and building double tracks will not be economical. It will, however, be hard to get below three hours from Oslo to Bergen or Trondheim on single track, as meeting trains will be very sensitive to delays. Travel time above three hours makes it hard to compete with air travel. There is no single-track high-speed railway in operation in the world at the moment (one such, the Botniabanan in Sweden is built for 250 km/h, but does not operate above 200). The VWI investigation suggests very long passing loops (15 km) to be able to pass at 160 km/h, and accept some delays without delaying meeting trains. Since these railways would be high-speed only, the passing loops need only to be 30 minutes travel time (80–100 km) apart (assuming one train per hour per direction).