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    Re: It's four-planet fix time...
    From: Antoine Couëtte
    Date: 2018 Aug 7, 10:22 -0700

    RE : Its-fourplanet-fix-time-Rudzinski-aug-2018-g42485

    Dear Greg,

    It required some time for me ;-) to recompute your Navy MK V Bubble Octant Observations published lately.

    Assuming that you "Hs" values do not require any "instrument correction" and using 70°F / 29.86'' - as you privately indicated to me meanwhile - with Height of Eye = 0', and assuming also that you did observe from N34°10.9' - W119°13.2' which - as a personal guess - was your actual full accuracy position earlier published many times, I am now getting the following results :

    Venus : -1.1 NM (A),   Jupiter - 1.1 NM (A),  Saturn +2.4 NM (T), and Mars -2.3 NM (A)

    yielding an observed position at  N34°10.9' - W119°13.2', lying just only 0.6 NM from your updated [GPS] position, into bearing 055°

    Lessons learnt:

    1 - On an operational standpoint and whenever possible it seems preferable to always process data to full computational accuracy, even when using limited/degraded/impaired accuracy instruments.

    Here we can see that your reprocessed End Fix is only 0.6 NM from your GPS position, i.e. much closer (almost 4x closer) than the position depicted on your graph: see my add-on onto your graph.

    2 - Well Done once again, Greg, you Wizard !

    Best Friendly Navigational Regards,


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