Celestial Navigation · Sight Reduction — Pub 229 vs 249
Compared with Pub. No. 229, Pub. No. 249 (Air tables) is characterized by:
- AHigher precision to a tenth of a minute
- BUse only for the Moon
- CFaster, lower-precision reduction suited to rapid use✓ Correct
- DRequiring a computer
Explanation
Pub. 229 gives altitude to 0.1' for full marine precision; Pub. 249 is quicker and to 1', adequate for many purposes and favored for its speed and the selected-star volume. Both use the assumed-position/intercept method.
Authority: Pub. No. 229 and Pub. No. 249 introductions
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