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    The Magnetic compass fix.
    From: Byron Franklin
    Date: 2012 Sep 25, 18:58 -0700

    In 1948 I was transferred to the USS Luiseno ATF 156 as a sea-man to work on the deck. My main job was to keep her from rusting, and painting was a day by day task. The ship’s mission was to tow large ship in the ocean also tow targets for naval ships to practice gunnery. The ATF would tow a target a thousand feet astern and the big ship guns would shot shells at the large 60 ton target. We would see Battle Ships with 16 inch shells flying in the air to the target. With the BB hull down the shells could be seen coming toward the ATF, some time to close to us,(cease fire) also shells skipping along the water like a flat stone along a pond. Thing did happen, like in haze or fog they would target us, or the skipping shells would skipped close to Block Island (cease fire). I was selected the hazardous water/General Quarters helmsman and after that the commanding officer pick me as a Quartermaster striker to work on the bridge. I did not go through the QM school as most QM’S striker does.
    My teaching for the bridge was more on the job training. I was not influenced by school training.
    My first use of the sextant was to measure the angle between the Target and the splash of the shells.
    My first use of a bearing circle was sighting NAVAIDS when transiting harbor waters. I soon learn to plot fixes on the chart. WW2 equipment was not like today; we obtained triangles and picked the center as ship position, as I was taught to do on board ship training. We normally selected Navaids in the lower half of the chart near where we normally operate. Far to the north was a large tank that was very visible and easy to include in the round of bearings for a fix. When I used it, it always increased the size of the triangle. I was told that it was plotted on the chart in the wrong position. Later when operation at a torpedo firing range that was close to the larger tank, we used the tank, with smaller triangles.” I thought that strange?” Later on another ship I learn to use that far Navaid and developed the Franklin Piloting Technique that uses the far Navaid to correct gyro and magnetic compass error.
    Magnetic compass error.
    All of the seaman educated by the book and schools are taught that all Line of Position are equal and that the center of the triangle is the ships position. (This is far from the truth.) This idea is hard to break because this is the navigation book/ bible/ class room teaching. It is obvious that the book is wrong, especially with the use of the magnetic compass.
    The magnetic compass bearings carrying the systematic Variation error and random (roll and pitch) and is harder to obtain with a hand held magnetic compass, like my compass, and more likely large in error. The far Navaid like my early days with the far tank and the rule of sixty is predicted to miss the ship with a far, closest point of approach, line of position. The far Navaid can give systematic compass error (such as variation) but should not be part of the fix. With corrected compass plot use only the two closer with a good spread as the fix. Recently I did go along the Newport Shore line to get some magnetic fixes.
    The Variation is 15 degree W, at Newport RI. So it was better to correct the variation. I knew where I took bearing so I could judge the accuracy, the short distance navaids were as I predicted the better fix. I did get good fixes using variation correction, many within 100 yds. Forget the book and teachings if you want to improve your bearings and fixes use the two short as the fix and use the farther Navaid for fix accuracy judgment and for compass error and correction. My advantage was knowing my charted position and on land although my hand held is a small gun like and the wind was blowing. My disadvantage was not having a clear 360 view. I feel that no one will go to the trouble; if they do they will learn and experience a new ball game. If someone tries please give me your thoughts Imay try to show more on you tube video?
    Byron:
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