Celestial Navigation · Sextant Corrections — Apparent Altitude
Sextant altitude is 25°00.0'. The index error is 1.0' OFF the arc and the dip is 4.0'. What is the apparent altitude (ha)?
- A25°05.0'
- B25°03.0'
- C24°55.0'
- D24°57.0'✓ Correct
Explanation
Index error off the arc is added: 25°00.0' + 1.0' = 25°01.0'. Then dip is subtracted: 25°01.0' − 4.0' = 24°57.0'.
Authority: Nautical Almanac; Bowditch (Pub. No. 9)
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