Navigation & Field Mapmaking
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Full new section text from Survival Solutions

Compass Navigation: Bearings, Declination & Route Finding
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https://noinbox.dev/survival/solutions/compass-navigation.html

Field principle
A compass is a direction tool, not a position finder. Combine it with a map, terrain, distance and checkpoints to avoid confidently walking the wrong route.
Quick visual reference. Read the explanations and limitations before use.
On this page
Identify the compass parts
- Baseplate: Clear edge and direction-of-travel arrow align a map route with the compass.
- Rotating bezel: Degree ring for reading and setting a bearing, usually 0–360 degrees clockwise.
- Magnetic needle: The north-seeking end points toward magnetic north when the compass is level and clear of interference.
- Orienting lines: Parallel lines inside the bezel that align with map grid north lines.
Take a bearing to a landmark
- 1. Aim: Hold the compass level, direction-of-travel arrow aimed at a distant distinct landmark.
- 2. Set: Rotate the bezel until its orienting arrow aligns under the north-seeking needle.
- 3. Read: Read degrees at the direction-of-travel index, not at the needle tip.
- 4. Travel: Choose a close intermediate landmark along that bearing and walk to it; repeat the check.
Convert magnetic and true bearings
- Know the datum: True north, magnetic north and map grid north differ. Read the map legend and its north arrows.
- Use the current declination: When east is positive and west negative: TRUE bearing = MAGNETIC bearing + declination; normalize 0–359 degrees.
- Example: A 70° magnetic bearing at +4° east declination becomes approximately 74° true. A 70° magnetic bearing at −4° west becomes 66° true.
- Reverse: Magnetic bearing = true bearing − declination. Do not correct twice when using an already-adjusted declination compass.
- Check location/date: Declination varies with location and time; older printed map values can be wrong.
Orient a map and measure direction
- Find the north reference: Read map north, grid north, scale and contour interval; use matching north references consistently.
- Align the map: Place compass on the map, adjust for declination, and rotate map and compass until the needle aligns with the orienting arrow.
- Set a course: Join your current known point to a destination; place baseplate edge along the course and rotate bezel until its north lines parallel the map grid.
- Cross-check: Compare expected terrain features, path junctions and crossings. Do not follow a bearing blindly across hazards.
Avoid common errors
- Metal and electronics: Move away from vehicles, steel structures, magnets, phones and electrical equipment while taking a reading.
- Reverse-bearing confusion: A back bearing is 180° opposite the forward bearing (add or subtract 180°). Check before retracing.
- Lost position: Stop, shelter if necessary, identify last known location, retrace only when safe, and use emergency communications if in danger.
- Practice first: Test on a known route in daylight, using more than one visible checkpoint.
Further reading & source material
Use these sources to validate local rules, technical standards and updates. No emergency article replaces official alerts or trained responders.
- NOAA — Magnetic declination and bearings
- USGS — Orient a map with a compass
Related quick references
Field mapmaking
Map symbols quick reference
Back to Navigation & Field Mapmaking

SOURCE LINKS
https://www.ngdc.noaa.gov/geomag/declination.shtml
https://www.usgs.gov/educational-resources/how-get-your-map-and-compass-face-same-direction


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Field Mapmaking: Sketch Maps, Scale & Terrain
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https://noinbox.dev/survival/solutions/field-mapmaking.html

Field principle
A useful field map emphasizes consistent reference points, a dated north arrow, relative distances, hazards, and clear labels. A sketch is for orientation, not a substitute for surveyed maps in high-risk navigation.
Quick visual reference. Read the explanations and limitations before use.
On this page
Set a purpose and north reference
- Choose the use: Draw for walking, evacuation, campsite layout or handoff to a rescue team; the needed accuracy differs.
- Record orientation: Mark true or magnetic north explicitly and the date, not just an unexplained N.
- Define scope: List start point, destination, water, terrain barriers, safe refuge, exit routes and areas you must avoid.
Collect observations
- Anchor known points: Begin with recognizable fixed landmarks such as bridges, trail crossings or surveyed markers.
- Measure route distance: Pace a known 100 m distance to estimate your pace length, then record steps on each trail segment.
- Use bearings: Take compass directions between visible landmarks while away from magnetic interference.
- Record changes: Log bends, junctions, stream crossings, slopes and prominent ridgelines immediately in your notebook.
Use scale and symbols
- Choose scale: At 1:10,000, 1 cm represents 100 m on the ground. Write a numeric and a graphic scale bar.
- Use a legend: Symbols must be explained. Label bridge, river, forest, path, cliff, buildings, hazard and water sources.
- Draw line types: Solid for confirmed paths, dashed for uncertain tracks, hatched or shaded for danger/steep ground.
- Contours: Contours join equal elevations; close spacing suggests steep slopes, wide spacing gentle slopes.
Validate the sketch
- Fix direction errors: Compare the rough map with an existing trusted paper or offline topographic map if available.
- Check the route: Test whether distances and intersection order match observations; note uncertain areas clearly.
- Make a handoff copy: Include author, date, area, north reference, map scale, known coordinates when available, and a short written route description.
- Never extrapolate safety: Do not invent bridges, crossings, water sources or exits; mark unknowns rather than guessing.
Further reading & source material
Use these sources to validate local rules, technical standards and updates. No emergency article replaces official alerts or trained responders.
- USGS — Topographic map symbols
- USGS — What is declination?
Related quick references
Compass navigation
Map symbols quick reference
Back to Navigation & Field Mapmaking

SOURCE LINKS
https://www.usgs.gov/educational-resources/topographic-map-symbols
https://www.usgs.gov/faqs/what-declination


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