Long-Term Service, Fleet, and Robustness Planning for Bali LRT Phase 1A Airport Access

Abstract

Bali LRT Phase 1A is a planned 6.04-km airport rail connection from I Gusti Ngurah Rai International Airport to the Sunset Road area. Its Final Feasibility Study (FS) presents operating quantities at seven forecast horizons. This paper asks what sequence of operating decisions is implied when those quantities are read together. Using the FS as the only numerical source, demand-based service is reconstructed, applied headway is compared with that minimum, fleet needs are checked from the 29-min round-trip time, and transition timing is stressed at ±10% and ±20% demand. The seven horizons collapse into four service states: 10, 8, 7, and 6 min. Passenger fleet requirement follows 4, 5, 6, and 6 trainsets. The last step is therefore not another fleet-purchase point; service becomes denser with the same six passenger trainsets while the passenger-baggage route-conflict indicator reaches 31.51%. Demand deviation mainly changes the calendar. In the +20% case, thresholds associated with the baseline years 2039, 2049, and 2059 are crossed at about 2033, 2041, and 2044. For long-term planning, these results support treating the FS years as review points tied to observed demand rather than as fixed activation dates.