Celestial Navigation · Time — Zone Description East
Your DR longitude is 75°E. What is the zone description?
- A+5 (wrong sign for east)
- B−5 (subtract 5 hours from ZT)✓ Correct
- C−6
- D−4
Explanation
75 ÷ 15 = 5 exactly. East longitude takes a minus sign: ZD = −5. You subtract 5 hours from zone time to obtain GMT/UT (east longitude is ahead of Greenwich).
Authority: Bowditch (Pub. No. 9), Time
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