Report source applies to the entire analysis, PDF, CSV and AI review. Vessel selection can further narrow each report.
Three-vessel comparison
Independent metric indices. Each vessel is compared with its own earlier reference; there is no overall score.
100 = own reference. Higher fuel/speed indices indicate improvement within matched observations. Oil indices show quantity change: higher means more oil, not better lubrication. Measured values remain visible even when a matched index is pending. Missing source measurements are labelled separately. Core measurement coverage is separately shown as a percentage. Index bars stop at 200; the number always shows the full result.
Scoring method, coverage and interpretation
Main-engine RPM & fuel
Main-engine fuel only, shown separately from auxiliary engines and boilers. Recorded consumption is available even when weather or operating-state data is insufficient for an optimum RPM.
Running RPM: report-hour weighted mean of positive RPM. ME MT/24 h: interval fuel × 24 / interval hours. ME kg/NM: matched main-engine fuel × 1000 / matched distance. Sources and their coverage remain separate; all operating states are included.
Fuel scope: main engine only. + DG (diesel generator) consumption will be added to the calculation in a future update. Speed basis: reported SOG (kn).
Latest main-engine records
Latest 20 records for the selected chart vessel/source. The full source ledger and CSV include every record. MT = metric tonnes; NM = nautical miles. Zero or missing distance has no per-mile result.
Source health & coverage
A missing observation stays missing. Totals from separate sources are never added together.
Performance relationships
Explore raw observations by vessel and source. Comparable operating bands are assessed below.
Three operating objectives
Observed, qualified bands for each vessel, source, loading and draft. No extrapolation outside measured RPM.
Observed RPM bands and qualification
Hull, propeller & slip monitor
Look for persistent power increase at matched STW, load, draft and mild weather. A review signal is not a fouling diagnosis.
Lubricating oil intelligence
Cylinder oil, main-engine system oil and auxiliary-engine system oil. Units and source periods remain explicit.
Source reconciliation
Calendar-day comparisons flag differences for review. Reporting periods may differ; this is not an automatic calibration verdict.
Source evidence ledger
AI technical review
Server-side ChatGPT analysis grounded in this snapshot.
The review sends the numerical analysis summary to the configured OpenAI service. It does not change records or machinery settings. PDF generation remains available while the review runs.
Methodology
Fuel per 24 hours uses the verified reporting interval; main-engine fuel per nautical mile uses fuel and positive distance from the same source record. Continuous passage and weather screening apply separately to optimum RPM assessment. SFOC requires propulsion energy for the same source period. WNI times remain unconfirmed until selected above. VAF daily totals use their source calendar day.
Oil volume is never silently converted to mass. Hull and propeller screening requires matched conditions and STW. Operational decisions remain subject to machinery limits, passage planning and onboard confirmation.
ITTC in-service performance guidance · Manufacturer lubrication reference · Engine-specific instructions take precedence.