Estimated position-error (covariance-based) of a two-body celestial fix given sight crossing angle and per-sight random error.
Formula
$$ \sigma_{fix} = \frac{\sigma_{LOP} \sqrt{2}}{\sin \theta} $$
Symbol legend
| Symbol | Meaning | Unit | Source |
|---|---|---|---|
| $\theta$ | Angle between LOPs | deg | sights geometry |
| $\sigma_{LOP}$ | Per-sight error (1σ) | nm | sextant precision |
Sources
- Bowditch Pub.9 Ch.22.