Risk analysis of the Type 93 tilting system

Unstad conducted a comprehensive risk analysis of the tilting system on Type 93 in response to findings identified during maintenance. The analysis covered not only the tilt mechanism itself, but also relevant components within the bogie system, and included electrical, hydraulic, and mechanical subsystems. The purpose was to establish a holistic understanding of system functionality, identify root causes of deviations, and assess implications for operational safety, reliability, and performance.

The hydraulic assessment included pressure measurements, inspection of cylinders and emergency accumulators, and a review of hydraulic schematics and technical documentation. The analysis identified deviations affecting tilt system performance, including incorrect carbody positioning and indications of leakage in check valves, which were flagged for further follow-up. In addition, deviations in vehicle ride height were identified and investigated as a potential contributor to system faults and undesirable loads.

The project was carried out through a combination of on-site inspections, technical analysis in Oslo, and close coordination with key stakeholders, including the operator, owner, and maintenance organization. The final report documented the findings and provided concrete recommendations for corrective actions, an improved maintenance strategy, and further follow-up, with the aim of increasing operational reliability and efficiency.