Celestial Navigation · Sight Reduction — Z to Zn Northern Latitude
In north latitude with LHA greater than 180°, the azimuth angle Z is converted to true azimuth Zn by:
- AZn = 360° minus Z
- BZn = Z (no change)✓ Correct
- CZn = 180° minus Z
- DZn = 180° plus Z
Explanation
In north latitude: if LHA > 180°, Zn = Z; if LHA < 180°, Zn = 360° − Z. (In south latitude the rules are Zn = 180° − Z for LHA > 180°, and Zn = 180° + Z for LHA < 180°.)
Authority: Pub. No. 229 / Pub. No. 249 conversion rules
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