On 3 May your 1009 zone time DR position is...

Question 1 of 2707066636eea28f7522a1c51adf0

On 3 May your 1009 zone time DR position is LAT 30°01.0'N, LONG 123°15.0'W. Your vessel is on course 330°T at a speed of 8.6 knots. What is the zone time of local apparent noon (LAN)?

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Question 1 of 27070

On 3 May your 1009 zone time DR position is LAT 30°01.0'N, LONG 123°15.0'W. Your vessel is on course 330°T at a speed of 8.6 knots. What is the zone time of local apparent noon (LAN)?

🔍 Key Concepts

• Local Apparent Noon (LAN) occurs when the Sun is on your local meridian (Sun’s LHA = 000°). • Relationship between longitude and time (4 minutes of time per degree of longitude). • How course and speed affect the DR position at the moment of LAN.

💭 Think About

• First, estimate around what clock time the Sun will cross your local meridian at about 123°W, compared with the standard 1200 zone time meridian. • Figure how far you will move along course 330°T between 1200 and the probable LAN time, and how that changes your longitude. • Decide whether LAN will occur before or after 1200 based on your changing longitude and refine your time estimate accordingly.

✅ Before You Answer

• Verify which time zone meridian applies to LONG 123°15.0'W and how far your DR longitude is from that meridian in degrees and minutes. • Convert the longitude difference to time difference using 4 minutes of time per degree of longitude (and proportion for minutes of arc). • Check the sign of the correction: are you west or east of the time zone meridian, and does that make LAN earlier or later than 1200 local zone time?