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    Re: And even more celestial-in-case-GPS-goes-down silliness
    From: Rommel John Miller
    Date: 2016 Jul 18, 14:51 -0400

    “teach all Navy personnel” sounds suspect, (like the tale of Chicken Little, or the new clothes the Emperor wears) but I am sure once properly learned no one would forfeit their knowledge of Celestial Navigation willingly.  Why?  Because not only does someone have to learn the proper ways of caring for the sextant, adjusting the sextant and aligning the sextant, not to mention in the sight of “letting her rise” as opposed to “bringing her down” let alone rocking and rolling the sextant to get an arc. 

     

    This is why every lifeboat and/or ditch bag should have one of those Davis Mk 3 tucked away safely. 

     

    Think of the Hitchcock film called “Lifeboat” it is a study of a varying group of survivors from a U-Boat attack, trying to survive.  A person aboard happens to find an Aircraft sextant which the Mk. 3 is based upon.  And from there the one person aboard with the rudimentary knowledge of celestial figures out pretty closely as to where they are; I believe they also had a compass. 

     

    Then think of Redford in “All is Lost” and his first glimpse of Celestial comes from finding where it is snugly stowed away, and then unpacking it for the first and last time.  Somehow a copy of Blewitt’s’ “Celestial Navigation for Yachtsmen” appears, and he studies it and within one day knows what to do with a sextant a pencil and paper.  Too bad he doesn’t have the sight reduction 249 which the book references and pretty much assumes the navigator to have.  He also has the boat’s compass, and while Blewitt doesn’t advise the reader on the need to correct the compass and correct your timepiece before every sighting, but Toghill in “Celestial Navigation” does; he also relies upon 229 for sight reduction. 

     

    If I were raw to CN and I really needed it after the electronics fail, and water on them especially salt water, is more common to their failing than a satellite actually falling out of the sky. 

     

    Case in point my Garmin GPSMap 640, the GPS is only as good as its internal database of informatics is.  An outdated, and old road map let alone nautical chart can spell problems.  Old maps and charts allow us to generalized and use DR as well as EP somewhat better, but if you navigate the Chesapeake you should have all the Notice to Mariners with correction made to your charts well in advance of counting on them to show shoals and obstructions. 

     

    How many of us are anal about ensuring our charts are up to date and in agreement with Notice to Mariners?  I know the Navy was (when I was in and a QM) and still is I hope. 

     

    Even then does the Navy trust an E-3 or E-2 Striker, or even a E-4 (Third Class Petty Officer) with the valuable ship’s sextant?  Hell no, only the Navigation officer was allowed to touch it, let alone adjust it.

     

    Maybe a CPO (E-7) or above might be allowed to handle the sextant, but time and rank does have its privileges. 

     

    The rest of us had to learn CN on something like the Davis Mk 15.

     

    It is silly to me that they or anyone dropped CN in the first place, to rely entirely on the technology of electronics.  Since I was in the Navy of the IBM card and 1.5” magnetic tape reels, I can vouch on how easy it is for a system to fail. 

     

    Or as my math professor taught me in College:  ALL SYSTEMS LEAK, and that is so true of Weaponry control aboard ships and subs.  One my ship you never knew when an “Emergency Alpha” would be called, but it means a spill of Alpha grade particles somewhere down in control.  Alpha grade are pieces of radioactive material, and why all hands had to stand fast and steady was to ensure even by accident someone not on the haz mat might get contaminated.  It was serious stuff and the Marine Detachment aboard were the real cops we had aboard ship.  If anyone moved and was caught, during a drill or god forbid the real thing, the Marines would tear that sailor a new ass-hole.  Something about a gung ho marine staring anyone down, it is enough to make you crap your pants.  Let alone they carried the equivalent of AR-15’s only twenty time more potent and powerful. 

     

    Now, since revile is at 0530 aboard ship, it was usually before the sun began to peak over the horizon, and the duty NO and Petty Office could take the Dawn shot of three celestial objects; We took a midmorning shot, noon shot and midafternoon shot of the Sun and then then another shot at dusk of three objects.  Usually Sirius, Betelgeuse, and Venus. 

     

    The site below reminds us too that Betelgeuse will one day, far off but not too far off will cease to be, like so many satellites. 

     

    http://earthsky.org/brightest-stars/betelgeuse-will-explode-someday

     

    RJ Miller

    Hebron, MD

     

    From: NavList@fer3.com [mailto:NavList@fer3.com] On Behalf Of Lu Abel
    Sent: Monday, July 18, 2016 1:49 PM
    To: rommeljohnmiller@gmail.com
    Subject: [NavList] And even more celestial-in-case-GPS-goes-down silliness

     

    A group of US Senators has introduces a bill that will require the Navy to "teach all Navy personnel" celestial navigation "in case GPS goes down."

     


    Probably more due to sensationalist journalism than bill contents, but this article does not specify whether, for example, medical personnel would be required to know celestial...

     

    I forwarded this to a fellow US Power Squadrons member who is currently studying our top offshore and celestial navigation course.   I didn't realize that he was ex-Navy. 

     

    His reply was "The Quartermasters on our ship were required to take sextant sights annually to show their skills.  None ever got it right and no one cared.  Even then the entire ship would have been useless if we did not have a means such as SatNav (predecessor to GPS) to verify our SINS (Ship’s Inertial Navigation System).  Once rendered invalid, we could still get home using SINS or at least point in the right direction using our WWII Sperry gyrocompass (which all ships carried).  I am sure that today’s inertial platforms can go for longer times between verification than ours could.   Somehow I do not think that sextant coordinates would be of much use to fire a missile and if we could not fire missiles, we had no purpose but to go home."    


     

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