Operation of electric trains at GKB

On 4 August 2025 at the first time electric trains started operation at GKB in regular passenger service. To quickly solve this need, GKB has rented 12 double-deck cars from DB of Dosto 1997 generation (built by Adtranz/Bombardier Transportation), including driving trailers to offer the low-floor entrance. From these cars were formed four three-car rakes, of them one is a reserve and three, sandwiched by Vectrons, are running as a temporary solution on the S6 line Graz Hauptbahnhof - Wies-Eibiswald according to the current timetable (i. e. outside the Koralmbahn), with a maximum speed of 140 km/h.

The Vectrons are hired from Railpool (193 801 and 805) and from Beacon Rail (X4E 601, 604, 862, 867 and 876). One Vectron is used as a reserve. The sandwich operation is applied because the section (Graz -) Werndorf - Wettmannstätten is ETCS-only, and the double-deck driving trailers do not have ETCS OBU. The two locomotives are used because the turnaround times at Graz Hbf are too short to enable locomotives to switch on the front of the trains (head shunt reversal).

Electric operation from December 2025

Moreover, GKB has bought from DB 22 double-deck cars of Dosto 1994 generation, which are since April 2025 at the DB Fahrzeuginstandhaltung (FZI) Neumünster works for interior refurbishing. One of the cars is to be used for spare parts only, thence it will be not refurbished. The work on the first cars is scheduled to be completed by December, so that from the 14th, these cars with the new exterior design of the S-Bahn Steiermark can run on the modified S6 line via the Koralmbahn and with an expanded transport offer. The remainder of the batch of 21 cars is scheduled to be completed by June 2026. Subsequently, the 12 rented cars will be returned to DB.

In total seven three-car rakes will be formed from the refurbished cars, the driving trailers again without the ETCS OBU. These trains will run on the Koralmbahn at a top speed of 140 km/h, again hauled by the Vectrons, however no more sandwiched, because the trains will have at least a 15-minute turnaround time in Graz Hbf, so here the locomotives will be changed, in other words, another locomotive will be coupled to the front of the train, because there is no space for head shunt reversal. In contrary, the latter will be made in Wies-Eibiswald, where the are tracks availale for it.

Following this change, GKB will partially withdraw from service its own double-deck cars, built by SGP Graz in 1993 (five Class BS driving trailers, Nos. 201 - 205, and ten Class B intermediate cars, Nos. 101 - 110), which are usually hauled in the push-pull mode with the Class DH 1500 locomotives (six ones built 1975 - 78 by Jenbacher Werke). GKB was thus the first operator in Austria to use double-deck carriages. However, some of them will continue to be used also after December 2025 on certain S7 services between Graz Hbf and Köflach.

Even after 14 December 2025, the existing GTW 2/8 DMUs will continue to run on lines S61 and S7 to Wettmannstätten and Köflach (13 Class 5063 units were ordered at Stadler in February 2009, in service since December 2010, twelve are now in service, since one DMU was cancelled after an traffic accident 2018). The GTW 2/8s will be used until the latter sections are also electrified, at present envisaged in 2033 (initally expected in 2028).

For the future, GKB plans to purchase new EMUs for fully electric operation. According to the tender specification TED 762014-2024, 28 trains are to be delivered by 2028, with an option for up to 72 more. The first round of the tender, launched in December 2024, ended without a result, as SCHIG (Schieneninfrastruktur-Dienstleistungsgesellschaft) and in particular the Kärnten Land had such requirements for these new vehicles that their approval would have required too much expense, and the tender was therefore closed. A second tender was then launched, the deadline for submitting tenders being the end of June 2025.