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Re: Exercise #15 Day's Run (almost)
From: Jeremy C
Date: 2008 Jun 29, 13:52 -0700
From: Jeremy C
Date: 2008 Jun 29, 13:52 -0700
Correct, the departure Latitude should be 15 degrees, 14' North, not 14 degrees. Jeremy On Jun 14, 4:32�pm, "Giuseppe Menga"wrote: > Jeremy, > On my account at 14�14' N (the course is due west, so no change of latitude) > on the meridian passage the 10-6-2008 (decl. 23� 1.91'N) the height of the > sun was 81�12.10', taking into account all corrections Hs should be almost > 1� lower than yours. Did I do something wrong? > Giuseppe > > > > ----- Original Message ----- > From: "Anabasis" > To: "NavList" > Sent: Saturday, June 14, 2008 10:26 AM > Subject: [NavList 5443] Exercise #15 Day's Run (almost) > > Exercise #15 �Day�s Run (almost) > > There has been some request from members of the group to have an �old > school� exercise where �DR�s� are actual dead reckoning positions and > not GPS fixes; giving us a bit of ambiguity as to where the vessel was > at the time of the sight. �This exercise should fit that description. > The scenario is departing anchorage and then heading out to sea, where > position and other celestial checks will be done throughout the day. > The only given position will be the departure point, and all sights > will be based on the previous reductions and running DR tracks. > This scenario is the exact trip we made on 10 June 2008 from > departure until the end of my evening watch at 20h 00m. > > For all sights, height of eye is 106 ft, Index error is 0.0. �All > times are local zone time, and the ship is keeping �ZD-10. �The local > date is 10 June 2008. > > A ship takes departure from the Saipan anchorage at 9h 00m local > time. �Position is fixed by visual and radar LOP�s and is determined > to be Lat 14deg 14.0� N; Longitude 145deg 38� East. �The ship steams > on a course of 270 deg True at making turns (engine speed) for 12.0 > knots. > > At 10h 25m 59s, a lower limb observation of the sun is made. �Hs is > 62deg 22.4�. �Temp is 85deg F Pressure is 1010 MB. > > At 12h 19m LAN is observed. �The Hs of the lower limb of the sun is > 82deg 06.0�. �Temp is 98 deg F Pressure is 1010 MB. �Soon after LAN, > the navigator sees that the moon has risen and takes an observation of > the upper limb of the moon. �Hs is 6deg 20.8� at 12h 23m 20s. > Determine a running 12h 00m fix (noon position). �Also determine > distance run as well as course and speed made good since departure. > > At 16h 03m 42s a PM Azimuth of the Sun is observed on the starboard > gyro repeater. �The sun�s observed bearing is 286.4 degrees PGC. �The > course PGC is 273.5 degrees, Variation from the chart is 1.3 degrees > East. �Course per magnetic steering compass is 286.0 degrees. > Determine Gyro error and Deviation on this heading. > > At 1645 the ship alters course to 180 degrees true, maintaining 12.0 > knots. > > At 17h 25m 20s, a lower limb observation of the sun is made. �Temp is > 95deg Pressure is 1010MB. Hs is 18deg 55.6� > > Star time approaches, determine sunset, time of stars, determine LHA > of Aries, and select stars to be shot. > > Around 18h 15m, the moon approaches Meridian Transit (LAM). �The > following data is collected: > Moon UL: Hs 78deg 34.9� at 18h 11m 58s > Moon UL: Hs 78deg 37.5� at 18h 13m 03s > Moon UL: Hs 78deg 37.2� at 18h 13m 41s > Moon UL: Hs 78deg 36.4� at 18h 14m 20s > Moon UL: Hs 78deg 37.2� at 18h 14m 46s > Moon UL: Hs 78deg 36.1� at 18h 15m 27s > Moon UL: Hs 78deg 35.7� at 18h 16m 12s > Moon UL: Hs 78deg 35.4� at 18h 16m 42s > Moon UL: Hs 78deg 34.2� at 18h 17m 10s > Moon UL: Hs 78deg 33.4� at 18h 17m 42s > Sun UL: Hs 7deg 27.2� at 18h 18m 33s > Sun UL: Hs 7deg 15.8� at 18h 19m 17s > Sun UL: Hs 7 deg 08.8� at 18h 19m 50s > Sun UL: Hs 7 deg 01.2� at 18h 20m 27s > Determine the 18h 15m fix. > > As the sun was near setting, an amplitude was observed on the > Celestial Horizon. �The sun�s bearing was 294.7 degrees. �The ship was > steering 180 PGC, 168 per magnetic compass, and the variation off of > the chart was 1.3 degrees East. �Determine Magnetic Deviation at this > heading. > > PM star time was poor with clouds and a hazy horizon. �Only two bodies > were observed. �Temp was 84 deg F, pressure is 1010MB. > Arcturus was shot at 19h 20m 51s Hs is 60deg 34.0� > Dubhe was observed at 19h 13m 53s �Hs is 41deg 58.6. > Determine the 1900 star fix. > > Have fun > Jeremy- Hide quoted text - > > - Show quoted text - --~--~---------~--~----~------------~-------~--~----~ Navigation List archive: www.fer3.com/arc To post, email NavList@fer3.com To , email NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---