Gotthard Tunnel Derailment Sparks Debate over LL Brakes Used in Swiss and German Rail Freight Trains
German high-speed train operator Deutsche Bahn's braking system faces criticism from Swiss authorities as well.
The Swiss Federal Railways (SBB) have raised concerns over the LL brakes used in freight trains, a brake type also employed by the German Rail. Following a freight train derailment in the Gotthard Tunnel, Switzerland, the SBB are advocating for stricter maintenance and potentially even a ban on the use of these LL brakes.
The SBB's criticism is primarily based on a final report by the Safety Investigation Authority (Sust) regarding the derailment in 2023. The Sust attributed the accident to a breakage of the wheel disc due to fatigue cracks resulting from thermal overload. In response, the Sust has recommended longer maintenance intervals, improved testing methods, and a study on the influence of composite brake blocks, including type LL, on wheel thermal load.
The SBB's 60,000 freight wagons, according to German Rail, are predominantly equipped with LL brakes. The LL brake type, referred to as a "whisper brake," offers low friction and noise benefits. However, the SBB does not use any wagons with LL brakes in freight traffic, noting that the thermal stress on wheels is greater with this brake type compared to traditional grey cast iron brake blocks.
In August 2023, a freight train derailed in the west tube of the Gotthard Tunnel, with no injuries reported. The removal of the wagons and subsequent track renewal took months, delaying traffic without restrictions until a year later.
While recommendations following the incident do not specifically target German Rail’s use of LL brakes, the concerns over potential issues with thermal stress and material fatigue highlight the need for closer scrutiny of the LL brake system in the broader European rail network.
[Sources: ntv.de, mwa/dpa]
- German Rail
- Train Traffic
- Switzerland
Enrichment Data:
The Sust investigation revealed that material fatigue cracks found in LL brake pads were a contributing factor in the Gotthard Base Tunnel derailment. The increased thermal stress associated with the LL brakes may have aggravated these cracks, leading to a catastrophic wheel disk breakage.
The SUST has subsequently recommended several measures to address these issues:
- Enhanced Maintenance and Inspection: The European Union Agency for Railways should focus on enhancing maintenance and inspection of wheelsets to minimize the risk of similar incidents.
- Regulation Adjustment: Adjustments to regulations related to wheel diameter could help prevent future derailments.
- Investigation of Brake Shoes: The SUST has recommended investigating the role of brake shoes in increasing thermal load on wheels.
- Documentation and Design Changes: Safety notices were issued for SBB Cargo regarding equipment inspection documentation, and design modifications to switches were recommended to prevent derailments in the future.
The SUST's recommendations suggest the European Union Agency for Railways should focus on enhanced maintenance and inspection of wheelsets, as increased thermal stress associated with the LL brakes may have contributed to the material fatigue cracks found in the brake pads, potentially leading to future derailments. Considering the SBB does not use wagons with LL brakes in freight traffic due to greater thermal stress on wheels, German Rail might need to review its vocational training programs to ensure proper understanding of the impact of the LL brakes on wheel thermal load. The transportation industry, including rail freight traffic in Switzerland and Germany, should thus consider revising its community policy and finance investments to prioritize safer brake systems and more frequent maintenance checks.
