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    Re: Franklin Piloting
    From: Byron Franklin
    Date: 2012 Sep 7, 16:57 -0700

    Byron:Franklin Piloting: The two closer NAVAID intersection name as the fix need not be perfect and may be a distance from the actual position of the observer, but because of the rule of sixty and NAVAID relative position the large % or all of the error will be known. The magnetic compass fix will also benefit with increase accuracy for the same reasons that it will work with gyro compass.
    The % of error found depended on the indicator distance and the choice of NAVAIDS.
    The technique will improve or collapse the triangle even with some small compass change during taking bearing. The technique, with systematic or radon error, will always better the fix. The indicator or far bearing NAVAID if far enough, can allow the two closer bearings fix to be not accurate and still give good
    compass error correction. IE. If the far is about 6 Nautical miles the Closest Point Approach of the line of one degree error bearing will miss the ships position by about 100 yards.( rule of sixty) The two close, depending on distance(0.5) may miss by 17yds plus or minuses, this will be your fix. If your fix is 20 yds off true ship position than you are correct by about 80%, depending on the geometric of Navaids most cases 100%
    you need not know everything, and need not do the math or geometry, just try a few fixes
    and test for yourself. A sea story how the technique ended in BOWDITCH. I was over my time at sea and should have gone on scheduled shore duty (1973 ;) My sub SSBN 602 was going to the yards in Hawaii, I had a choice go to Hawaii or shore duty. My shore duty was at Newport RI. Officers Candidate School. I was to teach Navigation. When I reported in I was the junior chief. The OCS. Had class room classes and also at sea small craft (YP’S) classes. After I was teaching and had my own OCS classes, one of the senior chief said”I hate teaching in the class room using pin point fixes and than going on the YP’S with their bad gyro and the OC’S plotting triangles.” We were friends so I quickly drew a picture and explained my technique. The senior Chief went to sea with his OC’S for a few weeks, When he came back to the room class’s he told me that he taught the OC’S, what I taught him. The OC’S collapsed their own triangles and found compass error getting good fixes, while he (Chief) was able to sit on the chart table and observe. The senior Chief convinced me to write the technique and send it to HO. The head Navigation Sciences,” Ernest Brown “later wrote me a letter saying, he tried to break the technique, staying up all night and could not do so. He stated that in the WW2 he was on a Navigator on a DD and wish he knew of the technique and it was the best thing he ever evaluated. Soon after it was in the curriculum at Annapolis and OCS Newport and in Bowditch. The Civilian books never picked it for their use?
    Later I will give details on Navaid selection. Any Navaid selection will work and this information need not be known to find compass error but it will be interesting, especially if you teach navigation.

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