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    Re: sextant without paper charts
    From: Scott Owen
    Date: 2008 Oct 30, 21:24 -0500

    Lu Abel wrote:
    > Bill:
    > I suspect we are actually closer in viewpoints than you may think.
    > First of all, I was reacting to an earlier post where Scott seemed to
    > assume that because a just-launched submarine carried a sextant, it
    First, I didn't assume anything, merely trying to relay the current
    state of affairs albeit I did a poor job I admit.  The FACT is that if a
    submarine is not authorized for DNC usage for primary navigation then
    believe it or not [yes in the 21st Century] they would be required to
    carry a paper copy of ALL required navigation pubs/charts which would
    include HO229.  Not all submarines even today are authorized to use DNC
    for primary navigation.  I clearly stated that a prudent Commanding
    Officer would carry a copy but maybe not.  Finally, you never know what
    electronics will die during the heat of battle including your vaunted
    cheap calculators.  I can think of more than three scenarios in the heat
    of battle where a calculator and computers would easily become inoperable.
    > would also be carrying copies of Ho229.  Given that space on a submarine
    > is at a premium and that all six volumes (which it would need to carry)
    > take up more space than is allocated to the average enlisted sailor for
    > all his personal belongings, I had to wonder why one would do that
    Ridiculous.  This is just NOT TRUE.  You actually might be surprised how
    much room submarine sailors have for their personal belongings when
    compared to the actual space consumed by HO229.  I grant it's not a lot
    but more than your claim above.  They actually have significantly more
    room than what is required to store HO229.  Clearly, HO229 may take up a
    lot of room on your small sailboat but on a ship or submarine there is
    enough room to carry all the paper publications and charts that a
    submarine might need for any voyage.  Have you ever been on a nuclear
    powered submarine?  Somehow I doubt it.
    > rather than rely on a calculator.
    I believe I did include calculators but you chose to ignore that part.
    > When I learned celestial, I learned it using 229 for sight reduction (I
    > think scientific calculators were just coming out at prices that rival
    > today's prices for 42" HDTVs).  With a courses in numerical analysis
    > under my belt as a result of a graduate degree in computer science, I
    > think 229 is brilliant.  The requirement for an assumed position which
    > makes the LHA an integral number of degrees reduces the size of 229 by a
    > factor of 600(!).  And I understand how and why double-differences are
    > needed (when the second derivative of the function becomes significant
    > and linear interpolation is no longer accurate).
    WOW I'm impressed.
    > At the same time, I've had the opposite experience you had:  I didn't
    > find 229 giving me insight, just "follow the instructions and the answer
    > will fall out" (although with my understanding of graduate numerical
    > analysis I could figure out what was going on).  On the other hand,
    > perhaps because I am old enough that spherical trig was part of my high
    > school math curriculum, I suddenly found the calculator formulas
    > reviving long-ago learned math and found it reasonably easy to
    > understand the formulas.
    YGTBSM, that's a relief.
    > Different strokes for different folks, I guess.
    > And, yeah, I own a sailboat.   Getting there is all the fun.   BTW, I
    > just read about a collision in Buzzards Bay, Massachusetts where a 59'
    > foot sport fisherman rammed a sailboat, killing its skipper, because the
    > skipper of the sport fisherman was busy entering waypoints in his GPS.
    > I've seen way too many skippers so entranced by their electronics they
    > forget to look up and around, not only because it's required by the Nav
    > Rules, but because that's why we're out on the water in the first place!!
    Same problem on the freeway with people using their cell phone and
    texting... a real problem.
    > Peace,
    > Lu
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