Refraction correction for a sextant sun altitude at standard atmospheric conditions - Bennett empirical formula.
Formula
$$ R = \frac{1}{\tan(h_a + 7.31/(h_a + 4.4))} $$Symbol legend
| Symbol | Meaning | Unit | Source |
|---|---|---|---|
| $h_a$ | Apparent altitude | deg | sextant reading |
Sources
- Bennett G.G. - J. Nav. 1982.
- Bowditch Pub.9 Ch.20.