Features
CaptainCalc is organized by tabs. Below is what’s available today and what’s planned next.
Voyage
Voyage list & create
Manage voyages, create a new voyage, and keep operational context together.
Route & Waypoints editor
Plan a route, edit waypoints, and keep a reusable structure for typical passages.
Voyage templates
Save a known-good voyage plan as a template and reuse it.
Voyage dashboard (CPA/TCPA helpers)
Quick situational calculations integrated into voyage context.
Quick Calcs
ETA
Time to arrival based on speed and distance.
TTG + Fuel
Time-to-go and fuel estimate.
Rhumb Line
Distance & course for rhumb line legs.
Great Circle
Distance & initial course for great circle legs.
Squat
Squat estimate from speed and depth.
UKC
Under-keel clearance estimate.
Anchor Watch
Anchor radius monitoring logic (support).
Compass
Compass correction / true heading helpers.
Turning Circle
Simple turn radius/diameter estimates.
CPA / TCPA
Closest point of approach helpers (manual target).
Displacement
Quick displacement estimate from known components.
TSD ETA
ETA planning with set & drift.
MOB
Man overboard quick workflow helpers.
Set & Drift
Current set/drift helpers and conversions.
Fuel Endurance
Endurance/range from fuel consumption.
Dipping Distance
Line-of-sight / dipping distance helpers.
Tidal Height
Basic tidal height interpolation workflow.
Stopping Distance
Stopping distance estimate (operational support).
Pilot Ladder
Pilot ladder checks and quick helpers.
Mooring Line
Mooring line helpers and quick checks.
Parallel Index
Parallel index helpers and reminders.
Channel Speed
Channel speed planning helper.
Celestial
Observations (Sextant)
Record sextant sights with automatic corrections (dip, refraction, SD, parallax).
Almanac / Ephemeris
High-precision IAU SOFA Engine and NASA JPL DE440 ephemeris (±0.001°). Tracks 57 nav stars with finals.a DUT1 microsecond corrections. Validated against USNO Almanac with 523+ golden tests.
Sight Reduction (Intercept)
LHA, Hc, Zn, intercept, Toward/Away, with proof steps on screen.
Fix (2/3 LOP + Running Fix)
Compute fixes from 2 or 3 LOPs, with geometry quality scoring and running fix flow.
Find Bodies (Planning)
Visible bodies for a given position + UTC, rise/set/transit times, and best-geometry suggestions.
DMS Converter
Safe conversion and validation for DMS / DDM / DD formats.
Records
Stability cases
±0.001 m deterministic precision limits (GM, KG, GZ). Create stability cases, input loads/tanks, and review results with clear warnings.
Draft survey
Draft survey records and displacement workflow.
Tank soundings
Tank management: sounding/ullage context and calibration tables (CSV import).
Cargo planning / holds
Holds list, hold editor, and cargo records inside vessel profile.
Loading advisor
Operational support: density/volume based checks and planning helpers.
Regulations check
Quick checks tied to regulations modules.
Documents & checklists
Departure checklist templates stored as operational records.
Regulations (COLREG / IALA)
COLREG rules list
Quick access to rules and structured content.
Rule detail + diagrams
Lights and shapes diagrams for fast recognition.
Sound signals
Sound signal patterns for practice and reference.
IALA marks
Buoyage marks diagrams and quick reference.