Stadler has been contracted by Central European transport operator, Leo Express to install an additional traction system on its fleet of FLIRT trains.
The upgrade follows infrastructure improvements in the Czech Republic and Slovakia, where parts of the railway network are transitioning to the European standard 25kV/50Hz AC traction system.

Currently equipped with 3kV DC traction, the Leo Express FLIRT trains will be enhanced with the 25kV/50Hz system, enabling dual-traction capability. This will allow the trains to operate seamlessly across upgraded sections of the Czech and Slovak networks while continuing to serve routes in Poland.
The project has been made possible by a subsidy from the Czech Ministry of Transport, allocated to support the modernisation of Leo Express’s five-car FLIRT units.
Stadler will carry out the upgrades at its manufacturing facility in Frauenfeld, Switzerland. The project will involve the installation of the new traction hardware alongside significant software adaptations.
Czech suppliers will also contribute to the project, supporting local industry participation.
Key aspects of the upgrade process include:
- Integration of the 25kV/50Hz traction system into the Train Control and Management System (TCMS)
- Enhancements to the diagnostic system for improved operational oversight
- Addition of a control element to enable switching between the two traction systems
- Conducting a weight assessment, body strength tests, and technical running and brake tests to ensure safety and performance compliance
This collaboration is expected to enhance the reliability and operational range of Leo Express trains, aligning with broader efforts to modernise rail infrastructure in Central Europe.