ALL BEING well, Oslo’s 48 km rail link to the new twin runway Gardermoen airport will open in October 8. Airline traffic is expected to reach 11·7 million in 2000 and 16·8 million in 2010, with 50% of passengers travelling by train. Some doubt remains about the rail link’s opening date as construction has been delayed by use of a toxic water sealant in the Romeriks tunnel taking the line out of Oslo to Lillestrøm.

The same sealant caused difficulties in the Hallandsåsen tunnel forming part of a cut-off on Banverket’s west coast line in Sweden, and work was halted when it was discovered that cattle grazing nearby had been poisoned. This prompted the Norwegian authorities to ban the sealant in the Romeriks tunnel, particularly as the bore passes under a recreation area. As a result, leaking water is having to be pumped out in large quantities. Another consequence is that the water table under the Ostmark forest is falling, causing problems for buildings in the area. A ruling on whether the tunnel can open as planned was due at the end of last month.

The problem has also affected costs. Estimates dating from the 1992 decision to build the line put the price at NKr4·6bn, plus or minus 20%. Inflation has already swallowed the 20%, and the sealant dilemma has taken the price to NKr6·75bn.

NSB Gardermobanen A/S plans to run a weekday 10min interval service from Oslo Sentral, with alternate trains extended over the 18 km to Asker, from where fastest time to the airport will be 45min. At peak hours, all 16 trains will be needed.

Having passed through the Romeriks tunnel, at 13·8 km the longest in Norway, trains will continue from Lillestrøm over new alignment parallel to the existing line past Liersund, Lindeberg and Klofta to Jessheim, where the route turns west to the airport. Lillehammer bound inter-city trains will share these tracks, taking 1h 38min from the airport.

Should it not prove possible to open the Romeriks tunnel in October, airport trains will take the existing line to Lillestrøm, but pathing constraints will limit services to four an hour with the 10min non-stop timing from Oslo Sentral rising to 34min.

NSB Gardermobanen wanted its trains to have the look and feel of an airline service. Adtranz has obliged by producing 16 three-car sets with a bulbous nose and raised cab strongly reminiscent of an aircraft. Designed to run at 210 km/h under 15 kV 16 2??3 Hz catenary, each set costs around NKr50m.

Much effort has been paid to achieving low interior and exterior noise levels; the specification for a train passing at 25m from the track centre was 87dB(A). Pressure sealing and air-conditioning are provided, and one-class seating caters for 170 passengers. Pairs of seats weigh 29 kg and are arranged so that passengers can observe the luggage stacks positioned centrally at each doorway; there are racks over the windows too. An unusual feature are outboard video cameras linked to screens in the cab so that the driver can monitor the boarding process.

The last airport line train is fitted with tilting bodies, as are 16 similar four-car Norwegian Express 220-seat trainsets due to be delivered in 1998-2000 for NSB’s inter-city services to Bergen, Stavanger and Trondheim. o

CAPTION: Layout of Norway’s Gardermobanen Airport Express trains shows the luggage stacks positioned centrally in entrance areas

Airport Express suppliers

Stainless steel car bodies, radial steering bogies and GTO traction converters: Adtranz Sweden

Front end: ABB Offshore Technology

Three-phase traction motors (325 kW continuous rating): ABB Industrial Systems, Sweden

Automatic Train Protection: Adtranz Signal

Control console: Vestfold Engineering

Gangways: Woodville Polymer Engineering

Seats: Ring Mekkanik

Entrance doors: IFE

Internal doors: Quatromatic

Windows: Emmaboda

Windscreen: Isoclima

Couplers: Dellner

Brake system: SAB-Wabco

Pneumatics: Knorr-Bremse

Main compressor: Atlas Copco