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    Magnetic compass sextant fix teaching.
    From: Byron Franklin
    Date: 2013 Jan 2, 10:48 -0800

    [NavList] Magnetic compass sextant fix.
    From: Byron Franklin
    Date: 3 Dec 2012 12:14

    • Byron: Jeremy Allen Navigation on ” face book and Navlist”
    “I got me 2 new cadets :-) They are either going to love celnav or hate it when I am through with them. In either case, they will be well learned in the art.” Byron: Well stated! Jeremy!
    Byron: I have many thoughts and past experience on teaching Navigation. I joined the navy in 1948 after high school, and a few years working at various jobs. I was on the deck force working as a deck hand for two years and then to the bridge as a Quartermaster striker. I was on a very a junior ocean going ships, with very junior Navigator’s, so had to hit the books for my deep sea knowledge. My high school education was poor and my instructors were not knowledgeable. I like science.
    To my Navigation’s plus, was the amount of time spent at sea, for 9 years (1948…) the ship-type had first place for long underway time at sea, for US naval ships. This ship with a old bad gyro is why I developed the “Franklin Piloting Technique. My next sea experience was on sophisticated submarines, the
    SSBN A. Lincoln. This new Polaris sub needed qualified Navigation QM rate personnel, I volunteered and, after attending inertial Navigation School, I reported aboard as a chief and senior QM. After a few years the sub was to go to the yards for repair. I was overdue for shore duty and was transferred to Officers Candidate School “OCS.” in Newport RI. I was to teach Navigation, including celestial and piloting using class-room and underway small craft for training.
    The commanding Officer had sent a request to his seniors requesting that only officer were to teach these smart college graduates “OCS.” The CO’S request was soon evaluated by many educators and senior officers. After a few weeks the evaluation was completed. The decision was that the chiefs were to be kept. The OCS students that were taught by enlisted had better average grades and students made comments like “I can read,” I don’t need someone to read for me.” The chief’s appearance, background, credibility and sea stories were a plus. Later at OCS, I taught Radar and I was selected to teach “how to teach.” To new incoming instructors.
    While teaching navigation at OCS, a senior QM stated to me, that he did not like teaching three point lines of bearings intersecting fixes in the class-room, then, taking the OC class on small craft (YP’S) with bad gyro’s that caused plotting large triangles on the chart. This was bad for the credibility of the instructor and demotivator for the student. I quickly taught him my piloting technique; he was soon at sea with his students. The QMC came back to the class and cited that his students could solve compass error for themselves and they got that text book fix and were excited about their own experience and accomplishments. The QM talked me into putting the technique on paper and sending it to the Hydrographic Office. Mr. Brown at HO. evaluated it and placed it in the next Bowditch (1978.) Soon after, Annapolis, MD and OCS, Newport was teaching my technique.
    An evaluation of FPT at OCS. Newport stated “the students were taught the “Franklin Piloting Technique” and were able to find and correct the compass error them-selves.”
    So what is the message from the background above? The Instructor needs to be knowledgeable and creditable to breed confidence in to the novice. The novice needs to be motivated and please, by getting good results (fixes) from the start.
    I say he should start simple navigation by learning piloting with compass and sextant and FPT on the chart. He/she will get that good dependable fix, and completely understand how to plot, oppose to jumping into CELNAV and fear of not being able to get a fix. After the piloting raises understanding,
    then, CELNAV, and its form and chart work. Previous piloting fixing will give motivate, confidence and self-desire to spend necessary time for Celestial and love of Navigation now and in the future.
    I have experience this idea, one of my tasks underway was to do a day’s Navigation with Officers that were already schooled in Navigation. Most of them tried to get out of the day’s work because of past problems of no Celnav fix or bad fixes. Much of their trouble was fear of their past, bad fixes and not spending the time to improve, so why try. Going to all the schools and reading the text will not make the Navigator, School and text can lead the way. Getting good fixes from the start, motivation, time spent, and desire are the key to Navigation. A good start is to ensure motivation, by ensuring simple easy, good fixes from the start.

    Byron: I have been experimenting with magnetic compass fixes, with some luck
    and have used the sextant to best get a good fix. What do you think?
    I will also put this on you tube. I am sure someone has used this before?
    At sea can be an enjoyable experience and pastime.
    Navigation and getting fixes should be fun and part of the sailors, life at sea.
    Being good at navigation makes for the complete sailor or skipper.
    Most large boats and ships carry on board a magnetic compass and sextant and the skipper
    has had training either at a school or from the many books on navigation.
    Many skippers have tried to get good magnetic compass fixes only to find poor
    and confusion results on the chart. After additional tries the magnetic bearing compass is stored away
    the attempted fixing is put on hold, maybe permanently.
    If the skipper got what he believes a good fix, he would feel good about the idea and would continue to
    navigate and learn more and will demonstrate his ability to his/her friends. This success will carry the skipper on to more navigation goals and success.
    Why should one skipper get bad fixes and another get good fixes?
    Much is in the incomplete teaching of Navigation by schools and text.
    In 1950’s I was an instructor of Navigation at a Navy School at Newport RI.
    The classroom students were taught how to taking bearings and plot them for a pin point fix.
    The instructor demonstrated in the standard way, by class notes and blackboard.
    This simple idea of, taking bearings and plotting, would be understood by the student. But! When they went to sea on training boats with bad compasses, the pin point fixes turned into large triangles. The results were a turnoff to the students.
    The novice Navigator or skipper must experience early good results to continue and enjoy navigation.
    The magnetic compass can be used with the sextant to get that good fix in an easy technique.
    Easy Technique background: “compass to sextant fixes.”
    The Magnetic compass has 3 errors, 1.Variation, 2. Deviation (they are compass systematic error.) and 3. Random, (random is an unknown error that causes bad fixes.) If the random error is eliminated or reduced leaving systematic, good fixes will be the results.
    The sextant can give the systematic Lines of Position {LOP}
    1. Take one magnetic bearing LOP from the closes Navigation Aid correct the compass error for variation and deviation leaving a true bearing.
    2. Take a sextant angle between the close navaid & another Navaid and apply the angle to the closes magnetic corrected bearing LOP.
    3. Work each sextant angle off each LOP, for 3 or4 LOP’S
    4.Plot each LOP for the fix.
    Example: The magnetic bearing of the charted War College is 343 corrected “variation” -15W=LOP 328T. See Charted Blue LOP’S Newport RI. chart
    Sextant angle “War College and Rose Island LT (RI): 66 degrees/328-66=LOP, RI. 262T
    Sextant angle “Rose Island and Fort Adams (FA): 46 degrees/262-46=LOP 216T
    The Magnetic Compass and correction plotted in this example was a good fix, the sextant prove useful.
    There will be times that the magnetic plus corrections will still leave some doubt, resulting in a triangle.

    Doubt resulting in a triangle.
    The next example will use a 10 degree error instead of the known
    15W. This will introduce a known 5 degree error. The Franklin plotting Technique will be use to find and correct this known error.
    Example: The magnetic bearing War College 343 corrected -10W= (WC) LOP 333T. Pink LOP’S
    Sextant angle “War College and Rose Island LT: 66 degrees/333-66= (RI) LOP 267T.
    Sextant angle “Rose Island and Fort Adams: 46 degrees/267-46= (FA) LOP 221T.
    This example left a triangle, the selected fix is the intersection of the two closer Navaids WC&RI.
    Place yourself on the fix facing the far Navaid (FA). The far Navaid LOP runs to the left of the fix, and is a west error, correction is a minus. Reminder READ= Right East ADD/Left West subtract.
    A bearing of the far Navaid from the fix has a bearing of 216T.
    the difference between the far fort Adams original bearing of 221 and 216 is 5 degree.
    Subtract 5 degrees to correct each LOP’S will give a great fix and compass error of 15W.
    These simple rules can motivate the experience and the novice to enjoy navigation,
    and want to learn more.
    SEE you tube/navtec3331

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