NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Silicon Sea INTRO
From: Dan Hogan
Date: 2004 Mar 7, 07:41 -0800
From: Dan Hogan
Date: 2004 Mar 7, 07:41 -0800
THE CRUISE OF THE SILICON SEA (RETURN) rev. 07/03/2004 The Silicon Sea cruise is a series of navigation problems in the form of a circumnavigation. The navigation problems follow a route arond the world (see below). Archives for the navigation problems (Legs) are avaiable for download at http://www.wa6pby.com/ under Silicon Sea file ssea.zip. Newbies, Oldbies, In-between-be's and anyone just plain interested, join in. The only requirement is PARTICIPATE. If you are new to navigation, ASK questions on the list. This is a learning excersise for all of us. The *tentative* schedule of posts will be the the first and third wednesday of the month. This portion of the Silicon Sea cruise will start with Leg 83, approching Hilo, HawaII. Final home port is San Pedro, CA. Obviously those doing their navigation the old fashioned way, working for it, will need a current Nautical Almanac and Sight Reduction method. The dates for Leg 83 will be with the (2001) Nautical Almanac. Leg 84 will require using the year 2002 Nautical Almanac. However, the problems can be worked with any computer navigation program or nav calculators. All cruise and navigation information will be lifted from the 1973 +/- DMA Pilot Charts, Jimmy Cornell's World Cruising Routes, and any documents and charts available within the working group without incurring added expenses. This is a navigation excersize, not a simulated vertual voyage. THE ORIGINAL PLANNED ROUTE: Mallorca, Spain; Valleta, Malta; Port Said; Transit Gulf of Suez and Red Sea; Adan, Yeman; Maldive Islands; Cape Leeuwin, AU; Bass Strait, AU; Sydney Harbor, Australia; Wellington, New Zealand; Cape Horn, Rio de Janerio. FINAL ROUTE IS: Barbados; Panama Canal; HawaII; San Pedro, CA (home port). WE are five to six Legs from arriving at our destination port of San Pedro, California. NAVIGATION TOOLS: I recommend a Navigation Log Book, aka. Spiral Binder, to keep track of your doings. Believe me it can't be done 100% on a computer. A navigation referance text is recommended. Which ever text is issurd by your local government is satisfactory. There are many commercial volumes as well. The minimum tools you will need: 1) A pencil and ERASER. 2) Something to draw straight lines with. 3) Something to layout angles with. 4) Something to use as a plotting sheet. 5) Something to calculate trig. formulas with. 6) A current Nautical Almanac for sight reductions and sun problems. For problems prior to the what ever Nautical Almanac you have available You will need to use a computer navigation program or an online sight. 7) A pair of dividers. 8) A Sight Reduction method. (229, 211, spreadsheet, etc. or... 9) For us lazy souls, a Computer or Calculator Navigation Program of your choice. 10) Plotting Sheets or a piece of paper to make a plotting sheet. Anyone who thinks of something I missed post it to the list. Below is Dan Hogan's QED plotting for the financially under-privileged. Blatantly stolen from Self Contained Celestial Navigation with H.O. 208, John S. Letcher, 1977, International Marine, ISBN 0-87742-082-3. **************** Use lined paper, college ruled, Turn the paper 90d, so the lines are vertical. Ruled lines are used for longitude. Every sixth or twelfth line is darkened to represent a whole degree of longitude. (depending on the scale desired). Lines of latitude are added by construction, starting with the lowest latitude desired. Whole degrees are 60 miles. From your lowest Latitude line, at the most R/H longitude line, draw a line at an angle up from the Latitude of your lowest latitude line plus a 0.5d (i.e.:28.5d). For ten miles to each vertical line use 6 lines; for 5 miles to the line use 12 vertical lines. Where the angled line crosses your 6th and/or 12th line swing an arc until it touches your R/H vertical longitude line. This is the point of the next latitude line. Draw a line perpendicular to the longitude across the page. Repeat the process with each higher latitude (29.5d), etc. The bottom angle line, where it crosses the the intermediate vertical longitude lines, is the distance interval. 10 miles each line for 6 line spacing. 5 miles each line for 12 line spacing. This forms a handy scale of miles or minutes of latitude. The accuracy is within the tolerance of your #2 pencil point. Dan Hogan West Covina, CA Owner Navigation-L List http://www.wa6pby.com dhhogan1@earthlink.net Dan Hogan dhhogan1@earthlink.net http://www.wa6pby.com