NavList:

   

Reply

Gary J. LaPook wrote:
> That is the same question for which I have never gotten an answer. The
> arrangement of tables in H.O.249 and H.O. 214 is much more convient,
> often allowing you to do the entire round of sights with only one book
> opening.
> So who's bright idea was it to use LHA instead of latitude in H.O. 229?
>
> gl
>
>
>
> jhk wrote:
>
>
> "Nonetheless, from what I've seen of the NavList, most members will know
> most everything in the book -- and then some.  Which brings me to the
> one question I asked in the book that I can't figure out myself:  Why
> are the tables in H.O. 249 and H.O. 229 ordered differently?  I much
> prefer H.O. 249's order because latitude changes slowly at sea, while
> we're always skipping around in LHA"
>
>
>
> jhk wrote:
>
> > Hi Folks,
> >
> > Frank ask for a little info on my book.
> >
> > It all started from fairly complete notes that I had made for a couple
> > of short courses on CN.  Then I decided to expand them even more,
> > just in case other short-course opportunities cropped up.  That's when
> > I got curious about how other authors treated the subject.  I was
> > surprised to learn how different our approaches were.  Most all
> > authors had incorrect (or misleading) explanations of the "assumed
> > position" used in the St. Hilaire method (or they didn't attempt an
> > explanation at all), naive or incorrect figures, explained only one or
> > two kinds of sights, skipped lunars, omitted any computer
> > applications, had no historical perspective, and had no exercises for
> > the reader's practice and confidence building.
> >
> > So I decided it might be worth while to put my notes into book form.
> > I covered all of the above topics, while making the book topically
> > graduated, allowing the beginner to do a full sight reduction by page
> > 40.  The book is really all about the same level with only one
> > equation (the cosine law, naturally) used for all nine types of sight
> > reductions.  But the 72 exercises are graduated in difficulty, started
> > with only high school math and ending with asking the reader to show
> > that my exact lunar-distance clearing equation reduces the commonly
> > used 2nd-order power series.  So I hope, perhaps naively, that the
> > book has something for everyone.
> >
> > Nonetheless, from what I've seen of the NavList, most members will
> > know most everything in the book -- and then some.  Which brings me to
> > the one question I asked in the book that I can't figure out myself:
> > Why are the tables in H.O. 249 and H.O. 229 ordered differently?  I
> > much prefer H.O. 249's order because latitude changes slowly at sea,
> > while we're always skipping around in LHA.
> >
> > At the risk of being too wordy on the NavList, here's the contents of
> > the book:
> >
> > Celestial Navigation in the GPS Age
> >
> > 1.  Introduction.  The Heroic Era, The Story Retold.
> > The Fundamental Idea:  An Ancient Observation, the Key concept, The
> > Mariner's Angle.
> > The Equal-Altitude Line of Position: The 3-D Picture, The Limitations
> > of Mechanical Methods, The Only Solution.
> >
> > 2.  Plotting the Celestial Navigation LOP.
> > Coordinates:  Latitude and Longitude, Greenwich Hour Angle and
> > Declination.
> > The Navigation Triangle:  Sun and Earth, The Local Hour Angle, Azimuth
> > Angle and Azimuth.
> > Three Plotting Methods:  The Concept, Plotting Variables.
> >
> > 3.  The St. Hilaire Method.  The Captain's Idea, The Straight-line
> > Approximation, The Error, Why St. Hilaire?
> >
> > 4.  The Nautical Almanac - an Overview.  The Daily Pages, The Altitude
> > Corrections.
> >
> > 5.  Sun Sight Reductions.
> > Using Direct Calculation:  Attitude Corrections, The GHA and
> > Declination, The GHA and Declination Increments, The LHA, The Sketch,
> > The Triangle Solutions.
> > Using Tables: The Solution using H.O. 249, The Solution using H.O. 229.
> > Four Examples of Sun Sights.
> >
> > 6.  Sights of Other Celestial Bodies:  Availability, The Planets, The
> > Stars, Star Sights by Direct Calculation,  Star Sights by H.O. 249,
> > The Moon.
> >
> > 7.  Special Sights.  Polaris, Meridian Sights, Latitude without
> > Meridian Shots or UT, Latitude and Longitude from Meridian Sights,
> > Longitude from Altitude and Latitude, Time from a Lunar LOP and a Star
> > Fix, Position without St. Hilaire.
> >
> > 8.  Lunar Distance Sights.  The Concept, Taking a Lunar Sight, The
> > Distance Clearing Concept, Clearing the Lunar Distance, The Sight
> > Reduction,  A Lunar Example, Accuracy, So Why Lunars Today? Other Lunars.
> >
> > 9.  The Altitude Observations.
> > The Sextant:  The Horizon Mirror, The Telescope, Telescopes with
> > Traditional Horizon Mirrors.
> > Sextant Checks and Adjustments: The Telescope, the Index Mirror, The
> > Horizon Mirror, Index Error, Backlash, Sextant Arc Error.
> > Sextant Observations: Observations at Home,  Taking a Sight, Averaging
> > Sights.
> > Altitude Corrections:  Dip, Refraction, Upper and Lower Limbs, Parallax.
> >
> > 10. Operations at Sea:  Celestial before GPS, Celestial with GPS,
> > Those Special Sights, Plotting, Estimated Positions and Running Fixes,
> > Special LOP Orientations, Great-Circle Sailing, Time, Accuracy.
> >
> > 11.  Tables, Calculators, and Computers - the Debate:  Sight Reduction
> > Tables, Calculators and Computers.
> >
> > 12.  Insights from the Navigation Triangle:  Equivalent Triangles, The
> > Azimuth Rules, Understanding Inspection Tables, Special Cases of the
> > Azimuth Equation.
> >
> > 13.  Exercises for Understanding and Confidence:  Sight Reduction and
> > the Navigation Triangle; Navigational Astronomy; Courses, Distances,
> > and Charts; Lunar Distances; Computer Programming.
> >
> > Appendices:  A. Navigation Triangle Formulae,  B. Calculator
> > Keystrokes,  C. The Nautical Almanac,  D.  Sight Reduction Tables,  E.
> > Sight Reduction Worksheets,  F. Concepts in Plane Trigonometry,  G.
> > Sextant Arc Error Tables,  H. Dip Short of Horizon,  I. A Brief
> > History of Navigation,  J. Annotated Bibliography
> >
> > .....  John Karl
> >
> >
> >
> >
> > >


--~--~---------~--~----~------------~-------~--~----~
To post to this group, send email to NavList@fer3.com
To , send email to NavList-@fer3.com
-~----------~----~----~----~------~----~------~--~---

   

Reply