SBB ‘categorically rejects’ claims it missed ‘unmistakable warning signs’ in Gotthard derailment

SWITZERLAND: SBB has ‘categorically rejected’ allegations that it ignored ‘unmistakable warning signs’ during the 2023 Gotthard Base Tunnel freight derailment. The rebuttal comes as the national rail company has launched a series of new derailment detectors on the tunnel approaches, which have allowed it to lift the 160 km/h speed restriction.

Switzerland’s national railway has publicly hit back at allegations from a non-public expert report on the Gotthard Base Tunnel derailment that claims SBB failed to heed a series of warning messages that could have minimised the effects of the 2023 incident, rejecting its conclusions as ‘incorrect’.

The assertions were launched into the public eye earlier this month by Rundschau, a current-affairs programme from Switzerland’s German-language public broadcaster SRF.

Fault messages in the tunnel

Citing an expert report submitted to the public prosecutor’s office of the Ticino Canton, Rundschau reported that fault messages appeared after a wheel broke on a freight train travelling through the Gotthard Base Tunnel, but were not acted on while the damaged train continued running. The derailment ultimately caused more than €160m in damage and left one bore of the vital Alpine link closed for more than a year; the report, Rundschau said, concluded that SBB ‘could have prevented the worst’.

According to Rundschau’s account of the report, the fault sequence began after the wheel of the eleventh freight wagon broke. The damaged train continued running for several kilometres before the derailment escalated at the Faido multifunction station, where it was torn apart and caused extensive damage to the tunnel infrastructure.

The programme reported that several messages appeared at the Pollegio operations centre shortly afterwards, including one track section remaining red as if the train were still occupying it, even though it had already passed. Axle-counter faults were also apparently reported after the dangling wheel of the broken axle severed cables. Rundschau said the report concluded that the operations centre should have been alerted as the messages accumulated, around two and a half minutes before the derailment escalated.

The train reportedly triggered eight error messages in total, but neither the system nor staff recognised the danger. Rundschau reported that, according to its own research, similar fault messages had been appearing on dispatchers’ screens for weeks in two other sections because of defective axle counters. The broadcaster pointed to an SBB report that had assessed those faults as not posing an operational risk.

Josef Dittli, a member of the Council of States from Uri and president of the industry association of freight wagon owners, told Rundschau: ‘If a train can travel kilometres into the tunnel and a trail of error messages appears on the screens – if it lights up red in the control centre and nobody intervenes, then something is clearly wrong with the system.’

SBB’s response

While the document itself has not been made public, SBB has acknowledged the findings, issuing a detailed and highly defensive public response. The Swiss railway company fundamentally rejected the assessment, stressing that the conclusions cited were not shared by either transport safety investigation board SUST or the Federal Office of Transport.

‘This is incorrect and an isolated assessment’, the rail company said following the broadcast on Switzerland’s most watched German-language TV channel. Describing the portrayal as ‘false’ and ‘distort[ing] the technical context of the incident’. The rail company said that, firstly, the warning systems at the centre of the dispute were not designed to identify a broken wheel or a derailing wagon. ‘They monitor the infrastructure, not the technical condition of the trains’, SBB said. ‘Therefore, they cannot detect derailments, but rather prevent trains from entering if the infrastructure is not functioning properly.’

SBB said this was ‘precisely what happened’ during the Gotthard incident. ‘Because the infrastructure was damaged, no further trains could enter the tunnel’, the company stated, arguing that the safety systems performed their intended function. It also pointed back to the SUST final report, which it said confirmed that the cause of the accident was ‘the breakage of a freight wagon’s wheel disc’, rather than a failure of SBB systems or operational management. SBB says it ‘categorically rejects the expert opinion’s conclusion. The company’s management acted correctly at all times, and all systems functioned flawlessly.’

Opening up the speed limit

Yet, SBB has now installed the kind of dedicated infrastructure-side detection equipment that did not exist on the tunnel approaches at the time of the accident. In the same week as its public rebuttal to Rundschau, it commissioned new trackside derailment detectors at around 10 locations on the access lines to the Gotthard Base Tunnel.

The detectors have been installed before the portal cross-overs, a sensitive section where passenger and freight trains run at high speed and where turnouts allow trains to cross between tracks. By bringing the detectors online, SBB said it could now lift the temporary 160 km/h speed restriction that had been in place since the tunnel returned to operation in September 2024.

The company said the system was designed to identify a physical derailment on the infrastructure side, rather than relying on control-centre indications intended for other purposes, once again stressing this would not address the original cause of the 2023 accident as ‘derailment detectors cannot prevent derailments’. Their aim instead is to prevent a collision between two trains in case a derailment does occur.

Freight should ‘invest more than the absolute minimum’

For SBB, that fundamental limitation is why the responsibility must shift back to the maintenance of freight wagons used in international traffic. Stating it was in full support of SUST’s recommendations, the rail company is now demanding rapid official measures to improve maintenance standards. ‘To reduce the risk of derailments in the future, attention must be paid to the maintenance of certain freight wagons belonging to international wagon owners’, it said.

SBB also renewed its call for changes to liability rules in rail freight, arguing that the current framework places responsibility on the operator transporting a defective wagon rather than the wagon keeper. ‘The current situation is that if an accident is caused by a defect in a wagon, the railway undertaking transporting the wagon is liable, not the wagon keeper’, SBB said. ‘Wagon keepers therefore have little incentive to invest more than the absolute minimum in wagon safety. Liability legislation must therefore be amended.’