Finding where you are using what you can see — the foundation of coastal navigation
Contents
Use the links below to jump to any section:
- What a Visual Fix Really Is
- Why Visual Fixes Still Matter
- What You Need Before You Can Take a Fix
- Choosing Suitable Objects for a Visual Fix
- The Three-Bearing Fix (Conceptual Overview)
- Two-Bearing and Single-Bearing Fixes
- Accuracy, Geometry, and Fix Quality
- Fix Timing and Vessel Movement
- When a Visual Fix Is Not Reliable
- Common Civilian Mistakes
- Professional Habits for Reliable Visual Fixes
1. What a Visual Fix Really Is
A visual fix is a confirmed position on the chart, determined by observing real, physical objects outside the ship and relating them to charted information.
It answers one question only:
“Where is the ship right now?”
A fix is not an estimate.
It is not a guess.
It is not “roughly here”.
A fix is a statement of position with confidence.
2. Why Visual Fixes Still Matter
Visual fixing predates radar, GPS, and ECDIS by centuries — and it still survives because it works when everything else fails.
Visual fixes are:
- independent of electronics
- immune to signal loss
- immediately intuitive
- excellent at detecting drift and error
Many modern accidents occur in sight of land, where visual fixes were available but not used.
Professional navigators never abandon visual fixing just because electronics are working.
They use it to verify reality.
3. What You Need Before You Can Take a Fix
Before taking a visual fix, three things must already be true:
You must know what you are looking at.
You must know where it is on the chart.
You must know how to relate the two.
This sounds obvious, but most fixing errors happen because one of these steps is assumed instead of confirmed.
A lighthouse misidentified is worse than no lighthouse at all.
4. Choosing Suitable Objects for a Visual Fix
Not everything you can see is suitable for fixing.
Good fixing objects are:
- clearly charted
- fixed to the land
- easily identifiable
- well separated in bearing
Poor fixing objects include moving vessels, ambiguous shore features, or anything that “might be that”.
When in doubt, do not force a fix.
Wait for better geometry.
5. The Three-Bearing Fix (Conceptual Overview)
The classic visual fix uses three bearings taken to three separate charted objects.
Each bearing defines a line of position — a line along which the ship must lie.
Where three such lines intersect is the ship’s position.
The value of three bearings is not precision — it is confirmation.
If all three meet cleanly, confidence is high.
If they form a triangle, something is wrong.
That triangle is not failure.
It is information.
6. Two-Bearing and Single-Bearing Fixes
In reality, three perfect objects are not always available.
Two bearings can still give a fix, but with reduced confidence.
A single bearing gives position information only when combined with something else — such as a range, transit, or depth contour.
Professional navigation is about using what is available, not waiting for perfection.
7. Accuracy, Geometry, and Fix Quality
Not all fixes are equal.
A good fix depends on geometry, not effort.
Bearings taken to objects that are too close together produce poor fixes.
Bearings taken nearly ahead or astern are less reliable than those abeam.
The best fixes come from objects spaced roughly evenly around the horizon.
This is why fix quality improves with experience — the eye learns what “looks right”.
8. Fix Timing and Vessel Movement
A ship moves continuously.
This means:
- bearings must be taken quickly
- time must be recorded
- position must reflect where the ship was at that moment
If bearings are taken slowly, the ship will have moved between observations and the fix will smear.
This is why visual fixing is a bridge team activity, not a solo task when workload is high.
9. When a Visual Fix Is Not Reliable
Visual fixes lose reliability when:
- visibility is poor
- background lighting hides landmarks
- sun glare obscures detail
- objects are misidentified
- the ship is turning rapidly
In these cases, forcing a fix creates false confidence.
A professional navigator knows when not to plot.
10. Common Civilian Mistakes
Civilians new to navigation commonly:
- fix on whatever is easiest to see, not what is best
- assume landmarks are obvious when they are not
- ignore time and movement
- trust a “neat” fix more than a believable one
Neatness does not equal accuracy.
11. Professional Habits for Reliable Visual Fixes
Experienced watchkeepers develop habits that prevent error.
They constantly compare:
- visual bearings
- ship’s heading
- expected track
- charted dangers
They treat fixes as checks, not answers.
If a fix contradicts expectation, they investigate immediately — they do not adjust the plan to make the fix “fit”.
Closing Perspective
Visual fixing is not an old skill.
It is a human skill.
It teaches spatial awareness, judgement, and humility — qualities that no electronic system can replace.
Everything else in Terrestrial & Coastal Navigation builds on this.
Tags
visual navigation · coastal navigation · position fixing · bridge watchkeeping · chartwork fundamentals · maritime training