Distance off a landmark of known height using the sextant vertical angle. Classical pilotage method.
Formula
$$ d = \frac{h}{\tan(\theta)} $$Symbol legend
| Symbol | Meaning | Unit | Source |
|---|---|---|---|
| $h$ | Landmark height above sea level | m | chart |
| $θ$ | Vertical sextant angle | ° | observation |
| $d$ | Distance off | m (or nm) | result |
Sources
- Admiralty Manual of Navigation BR45.