EXERCISE 32 — LONG BY CHRONOMETER SUN (Numerical Solution)

NOTE:

 In the following formula,

  • If the LAT and DEC are of same name then sign is (-),
  •  If of contrary names then sign is (+) .

e32q4p2

P = 47˚ 52.9’

Since, sight is before mer. Pass. ,so LHA = 360 – P

LHA          = 312˚ 08.1’
GHA         = 161˚ 01.9’
Long. E    = 151˚ 06.2’

Obs. Long. = 151˚ 06.2’ E

e32q4p3

Azimuth = N 65.9˚ E
T Az          = 065.9˚ (T)
LOP = 155.9˚ – 335.9˚

  1. On 30th April 2008, in DR 00˚ 20’N 060˚ 12’W, the sextant altitude of the sun’s UL East of the Meridian was 44˚ 13.4’ when the GPS clock showed 01h 00m 52s. If IE was 3.1’ off the arc & HE was 20m, find the direction of the LOP and the longitude where it cuts the DR latitude.

                                   d    h     m      s
GMT                        30   13   00    52
LIT (W)                    (-)   04   00    48
LMT                        30   09   00    04

About the author

Vikrant_sharma

12 Comments

  • @vikarant_sharma diagram in first question is wrong obs long value is smaller than DR LONG so it should be drawn in left side of DR long

  • 2nd and 3rd point of the note is also wrong. Correct one is when the sun (and star) is east of the meridian it’s AM, at that time LHA is between 180-360 so P= 360°-LHA. when the sun and (the star) is west of the meridian at that time LHA is between 0°-180° , and LHA=P . Correct ans of the question is P= 49°38.8°… long=175°15.8°…. az=N80.1W or 279.9° true

  • The value of P is wrong. It should be 52°0.1′. Hence LHA would be 52°0.1′ and longitude = 004°29.6’E

    • Calculate latitude course and speed error for following ship
      A)ship steering 230°T at 22.0 knots in latitude 41°24S
      B)ship steering 140°T at 15.0 knots in latitude 56°00N
      Please solve this problem argent machinical project hy

  • solutions of formula cosP is wrongg … it matches the ans in the textbook bt when we try to solve it ans is slight different.. so it is humble request to u to pls correct the answers because students are facing difficulties when trying to get help from youe site …

Leave a Comment