Rail transportation plays a strategic role in supporting economic activity and regional connectivity in Indonesia, yet operational risks along busy commuter lines remain inadequately mapped, including on the Padang-Minangkabau International Airport (BIM) line. This study aims to identify potential failure modes, analyze operational risk levels, determine the highest risk priorities, and formulate mitigation recommendations for the Padang-BIM rail line operated by PT Kereta Api Indonesia (Persero) Divre II West Sumatra. A sequential exploratory mixed-method design was employed, combining a qualitative stage (semi-structured interviews) to validate and enrich the list of failure modes with a quantitative stage using the Failure Mode and Effects Analysis (FMEA) method. Data were collected from 18 purposively selected operational staff, covering four operational risk sources: human factors, equipment and infrastructure, environment, and management. Severity (S), Occurrence (O), and Detection (D) were rated on a 1-10 scale and combined into a Risk Priority Number (RPN = S x O x D). Inter-rater reliability was tested using Kendall’s Coefficient of Concordance. The results identified 44 failure modes, of which four were classified as High Risk and one as Medium Risk. The highest-priority failure modes were ignoring warning signs at unguarded level crossings (RPN=432), stalled or trapped vehicles at level crossings (RPN=400), and running through closed barriers at guarded crossings (RPN=378), all originating from road-user behavior classified under the human factor. Rail cracking due to material fatigue (RPN=162) and landslides damaging the track (RPN=144) were also identified as priority risks.