Celestial Navigation · Time
A vessel in west longitude has a zone description of +5. To convert zone time to UT you must:
- ASubtract 5 hours from zone time
- BSubtract 5 hours from UT
- CAdd 5 hours to zone time✓ Correct
- DMake no change; zone time equals UT in the western hemisphere
Explanation
West longitude zone descriptions are positive and are ADDED to zone time to obtain UT. (East longitude ZDs are negative and subtracted.) ZT +5 means the zone is 5 hours behind Greenwich, so UT = ZT + 5.
Authority: Bowditch (Pub. No. 9)
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