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Starpath Emergency Nav
Introduction • What is emergency
navigation? • Scope of this course • Preparation for navigational emergencies • Latitude regions and seasons defined • Time in navigation • Finding position vs keeping track of position • Choosing a route • Compass checks • Steering without a compass Lesson 2 — STEERING BY WIND AND SWELLS Reading the wind • Swells, waves, and ripples • Wind shifts Lesson 3 — STEERING BY THE STARS Being an explanation of the concept of steering "by the shape of the whole sky" • Or whatever part is showing • Using key ideas such as leading stars and trailing stars • Circumpolar stars • And numerous tricks for learning "the shape" • Including special star groups • Overhead stars • Half-latitude rule • The tropics rule • Polynesian star paths • Circumpolar star paths • Timing low stars • and more Lesson 4 — STEERING BY THE SUN Sunrise and sunset • Morning sun and afternoon sun • Local Apparent Noon • Solar time method • The shadow-tip method • The tropics rule for the sun • Sun crossing due east or due west • Sun compasses Lesson 5 — STEERING BY OTHER THINGS IN THE SKY The moon • The planets • Clouds, birds, and planes Lesson 6 — STEERING IN FOG OR OVERCAST SKIES How to make a magnetic compass • Direction finding with a portable radio • Streaming a line along the centerline Ocean currents • Tidal currents • Wind-driven currents • Coastal currents • Finding boat speed • DR errors from speed and direction • DR errors from currents and leeway • Progress to weather Lesson 8 — LATITUDE AND LONGITUDE AT SEA Makeshift altitude measurements and calibrations • Makeshift altitude corrections •Latitude by Polaris • Latitude from zenith stars • Latitude from horizon-grazing stars • Latitude from double transits of circumpolar stars • Latitude from the sun at LAN • Latitude from the length of day • Keeping track of latitude • Longitude from sunrise or sunset • Longitude from LAN (the equation of time) • Finding GMT from a known position • Keeping track of longitude Lesson 9 — COASTAL PILOTING WITHOUT INSTRUMENTS Signs of land at sea • Visible range of lights and land • Finding distance off • Running fix from radio bearings • Course made good in current Lesson 10 — WHAT TO DO WITH WHAT YOU'VE GOT (A SUMMARY) Routine navigation with everything • Position by radio contact • Everything but GMT • Everything but a sextant • Everything but sight reduction tables • Everything but a compass • Everything but an almanac • Nothing but GMT |