On 20 September your 0730 zone time position was LAT 28°58.0'N, LONG 152°26.0'W. Your vessel was steaming on course 225°T at a speed of 19.0 knots. An observation of the Sun's lower limb was made at 0931 ZT. The chronometer read 07h 29m 20s and was slow 02m 22s. The observed altitude (Ho) was 44°14.4'. LAN occurred at 1206 zone time. The observed altitude (Ho) was 62°49.5'. What was the longitude of your 1200 zone time running fix?
Official USCG Answer & Rule Citation
Correct Answer: Option B — LONG 153°23.5'W
The 0730 position is advanced to the time of the meridian passage. By determining the latitude from the meridian altitude and calculating the longitude based on the time difference from the prime meridian, the 1200 running fix is established at 153°23.5'W.
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