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Sea distance between ports via or around the canals, route map and ETA.
Tonnes a day from power and SFOC, voyage fuel, days left on board.
What a speed change does to fuel per day and per mile.
Tonnes from volume, temperature and density (ASTM Table 54B).
Navigation
Sea distance between ports via or around the canals, route map and ETA.
Compass, magnetic and true; variation, deviation and gyro error.
Distance and course between two positions.
Solve any one from the other two; arrival time across time zones.
Course to steer against a current; set and drift.
Amplitude and azimuth: the sun’s true bearing and the compass error.
Rise, set, meridian passage and twilights for any position and date.
Position after a course and distance (Mercator sailing).
Doubling the angle, four-point bearing, vertical sextant angle; wheel-over.
Hs to Ho (index error, dip, refraction, semi-diameter); latitude by meridian altitude.
The speed to arrive on time at a pilot station or berth.
Watchkeeping
Closest point of approach from two radar plots.
True wind from apparent wind, with the Beaufort force.
Distance to the horizon, geographic range of a light, dip.
Check a week of rest hours against MLC and STCW.
Clock changes between zones, across the date line, shared over the watches.
Validate an IMO number; decode an MMSI: kind of station and country.
Seamanship
FWA, DWA, sinkage by TPC and the cargo still to load.
Height at any time between low and high water; when the depth is enough.
Trim, hog or sag, mean of means; marks corrected to the perpendiculars.
Estimate GM from the roll period (IMO formula), and the reverse.
Barrass squat in open and confined water; UKC.
Cable to pay out for the depth, in shackles; swinging circle.
Expanding square and sector search legs, courses and times.
Engine
Tonnes a day from power and SFOC, voyage fuel, days left on board.
What a speed change does to fuel per day and per mile.
Theoretical speed from pitch and rpm; apparent and real slip.
Engine power from mean indicated pressure; mechanical efficiency.
Tonnes from volume, temperature and density (ASTM Table 54B).
Temperature for injection viscosity, from the fuel’s viscosity.
g/kWh to kilograms and litres a day, and back.
Three-phase kW, kVA and kVAr, current and generator load.
Pay and conversions
Daily and monthly wage, contract end, days on board, leave.
Knots, miles, fathoms, bar, kW, °C; position formats.
Reference
International Code of Signals flags and their meanings; spelling.
Lights and day shapes by vessel, with the rule.
Wind force, speeds, sea description and wave heights; Douglas sea state.
Distress, safety and working channels with frequencies; GMDSS frequencies.