Chart Navigation & Plotting · Fixes — Three-Point Fix / Station Pointer
A station pointer (three-arm protractor) is used to plot a fix from:
- AThe barometric pressure
- BA single compass bearing
- CDepth soundings only
- DTwo measured horizontal angles between three charted objects✓ Correct
Explanation
The station pointer's three arms are set to the two horizontal sextant angles measured between three identified charted objects; sliding it until each arm lies on its object fixes the vessel's position at the center. It gives a very accurate fix independent of compass error.
Authority: Bowditch (Pub. No. 9), Horizontal Angles
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