{"assumptions":{"capture_bunker":{"value":0.35,"note":"Share of bunker stems currently mis-chosen against the optimiser"},"capture_demurrage":{"value":0.5,"note":"Share of shore-attributable demurrage currently leaking"},"capture_offhire":{"value":0.5,"note":"Share of time-charter off-hire judged preventable"},"hull_threshold_pct":{"value":5,"note":"ISO 19030 loss at which underwater cleaning becomes economic"},"clean_target_pct":{"value":1.2,"note":"Hull performance loss achievable immediately after cleaning"},"clean_cost_usd":{"value":38000,"note":"Indicative underwater hull clean, MR tanker"},"polish_cost_usd":{"value":12000,"note":"Propeller polish"},"tc_overhaul_usd":{"value":26000,"note":"Turbocharger inspection and overhaul"},"meter_cost_usd":{"value":55000,"note":"Shaft torque meter plus Coriolis mass flow, per vessel"},"clean_lead_weeks":{"value":3,"note":"Lead time to arrange an underwater clean"},"density_share":{"value":0.11,"note":"Portion of the intake gap attributable to density correction"},"tc_fuel_estimate_usd":{"value":2145000,"note":"Estimated annual bunker spend on comparable per-tonne tonnage"},"working_margin_m":{"value":0.05,"note":"Margin the optimiser holds below maximum permissible draft"},"ukc_port_minimum_m":{"value":0.8,"note":"Port minimum under-keel clearance"},"ukc_conservative_m":{"value":1.2,"note":"Conservative fixed under-keel clearance policy"},"voyages_per_year":{"value":22,"note":"Liftings per vessel per year, coastal employment"}}}