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Thread: Navigators trophy

  1. #1
    Join Date
    Nov 2010
    Posts
    73

    Default Navigators trophy

    Hi all,
    I was wondering what facts the race committee considered, when they're deciding if the navigator's trophy should be awarded, and if there were any particular rules about it.
    I seem to remember that a similar award was given in other past long distance races for use of celestial navigation. For example, I also think I remember that in some other races A participant could use electronic navigation when within 25 or so miles from the finish.
    I am putting together a new boat, and in thinking about the radio/navigation package and was thinking about the technological disconnect that would exist between a boat using celestial only for position fixes, and still having the availability of weather routing software and up to the minute weather forecasts and data, not to mention radar. I would be interested to know how many participants in recent years have used only celestial, and how do they fare against the racers using modern equipment.
    Jim

  2. #2
    Join Date
    May 2009
    Posts
    195

    Default

    I think Steve won this trophy in 2012 by using an Astrolabe?

    Quote Originally Posted by jimb522 View Post
    Hi all,
    I was wondering what facts the race committee considered, when they're deciding if the navigator's trophy should be awarded, and if there were any particular rules about it.
    I seem to remember that a similar award was given in other past long distance races for use of celestial navigation. For example, I also think I remember that in some other races A participant could use electronic navigation when within 25 or so miles from the finish.
    I am putting together a new boat, and in thinking about the radio/navigation package and was thinking about the technological disconnect that would exist between a boat using celestial only for position fixes, and still having the availability of weather routing software and up to the minute weather forecasts and data, not to mention radar. I would be interested to know how many participants in recent years have used only celestial, and how do they fare against the racers using modern equipment.
    Jim

  3. #3
    Join Date
    Jan 2012
    Location
    Santa Barbara Sometimes
    Posts
    166

    Default

    The 2012 Navigation Award I received was based on (almost) daily position estimates during the SHTP that were based on sextant sight reductions using the Nautical Almanac Sight Reduction (NASR) method. I used a WWII Navy (White) sextant that I found on ebay more than 10 years ago, see it here: https://photos.app.goo.gl/rcTuKTUqoZQ5c01F2

    From my 2012 SHTP notes:

    “14July2012 Almost there
    At 1606 PDT, 2,108 nm behind, 126 nm to go. Should arrive (cross line) near Hanalei early tomorrow, Sun. Cataloged the sextant sights I reduced: 15 total with good EP’s, several RFIXes, and a great two-body fix (Jupiter and MoonUL).”

    Celestial navigation was standard blue-water practice before GPS became widely available in the mid-90s (and sat-nav before that). Sight reduction using HO249 was (is?) a more popular method than NASR; I prefer NASR because it requires the least volume of reference material – at the expense of more lookups and arithmetic. Noon sights, and/or running fixes on the sun, are generally the simplest way to get a daily position fix.

    Besides the WWII Navy sextant, I’ve enjoyed using a Simex I picked up in a nautical swap meet for a few hundred USD: https://photos.app.goo.gl/fCMsTlx4W1jtGLeB3 I’ve also used the low-end Davis plastic sextants with OK results. But I prefer, and get more accurate results using, metal sextants. There are some ‘great deals’ out there - here’s a cute and fully functional WWII merchant marine lifeboat package I recently picked up for $100: https://photos.app.goo.gl/UNyShcYZQhGA89yo1

    There are a lot of ways to do this! The USPS continues to offer classes (though not as often as they used to), and more expensive but less time consuming commercial courses are available. DIY may also be reasonable, but it’s easy to be overwhelmed…. Here’s a link to the material used in a noon sight primer/seminar I led in May: https://drive.google.com/open?id=0By...mN1U09YYUNmbVU which includes a list of some references I’ve found useful:

    – “American Practical Navigator,” (Bowditch), USG
    – “Dutton’s Nautical Navigation,” Thomas Cutler
    – “Sight Reduction Methods,” USPS
    – “Celestial Navigation,” David Burch
    – “Sextant User’s Guide,” Andrew Evans
    – “Celestial Navigation for Yachtsmen,” Mary Blewitt
    – “The Sextant Handbook,” Bruce Bauer

  4. #4
    Join Date
    Jan 2013
    Location
    Montara, CA
    Posts
    723

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    FYI - Blue Pelican has a PILE of sextants right now, just behind their counter. IIRC, one of them is a Plath.

  5. #5
    Join Date
    Jan 2012
    Location
    Santa Barbara Sometimes
    Posts
    166

    Default

    Quote Originally Posted by Gamayun View Post
    FYI - Blue Pelican has a PILE of sextants right now, just behind their counter. IIRC, one of them is a Plath.
    A used sextant can be a great deal, or not. Caveat emptor. “The Sextant Handbook” by Bruce Bauer has a “How to buy a sextant” chapter that is a must read for anyone considering buying a sextant (used or new). A sextant is an optical device designed to make angle measurements and so is only as good as the condition of its optical and mechanical parts. At the very least check these things:

    - General look over: Has it been dropped or otherwise damaged? All the parts there?

    - Corrosion? Check the adjustment screws and other moving parts. If it has a battery compartment (to light the scale), open it and make sure a leaking battery isn’t or hasn’t been in there. If you care about the light (it’s optional), test it.

    - Optical surfaces: mirrors, scope, filters should all look good. Dirt can be cleaned, but scratches may be a big problem, for example, let too much sunlight through. Don’t buy a sextant with damaged optics!

    - Check the basic alignment by sighting a distant (100 ft or more) small and distinct object, for example, a street light or car headlight, with the index arm set to 0. Adjust the micrometer and look for the double image; can you turn the micrometer so the images completely overlap? If not, the sextant needs to be adjusted. Sextants are designed to be adjusted, but don’t buy it unless you are sure it can be adjusted! This includes having the correct tools. There is no standard so many sextants come with custom adjustment tools.

    - Is there a carrying/storage case adequate for your intended usage, or will you make one?

  6. #6
    Join Date
    Nov 2010
    Posts
    73

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    Steve,
    Thank you for replying to my post. Congratulations on your achievement. If you don't mind, I would appreciate a few more details. Under the race rules, were you allowed to take any gps fixes at any time during the race? On the average, what was the distance between your celestial fixes and your DR positions? When you sighted land, were you where you thought you were? During the course of the race, what was your confidence level in your fixes? How much time daily, on the average did you devote to celestial? Basd on on your experience, can you quantify how much of a disadvantage is a competent celestial navigator to an equally well sailed identical boat with gps?
    Are you self-taught or professionally trained?
    Thank you,
    Jim B

  7. #7
    Join Date
    Jan 2012
    Location
    Santa Barbara Sometimes
    Posts
    166

    Default

    Jim,

    Oh boy, a quiz! Here’re some responses, hope it addresses your questions without being TMI:

    1. Under the race rules, were you allowed to take any gps fixes at any time during the race?

    Actually the race rule require at least two GPS aboard, and daily position reporting, but, AFAIK, the rules don’t address how one obtains the reported position, or requirements for the Nav trophy. The trophy is awarded at the discretion of the SHTP committee and/or chair. Might be a good idea for anyone seeking that award to, after reading the 2018 RRC, discuss their intended approach with the race chair before the race.

    2. On the average, what was the distance between your celestial fixes and your DR positions?

    At sea the difference between my celestial positions and GPS range from 1 to 20 nm, and averages about 5 nm. The classes I took required less than a 2-nm error and, with practice, that is pretty easy with sights taken in calm conditions, or ashore. Once the process is mastered reasonably well, it isn’t a big leap to practice it offshore; the new skill is hanging on while operating the sextant, and timing sights with swell.

    3. When you sighted land, were you where you thought you were?

    Yes, within a few miles.

    4. During the course of the race, what was your confidence level in your fixes?

    When reducing a sight, one generally starts with a DR based on the last fix and logged S and C. Usually I find the new estimated position, running fix or two-body fix within ~5 or 10 nm of the DR. Occasionally they come out widely different (more than ~20 nm), and then I look for my arithmetic or look-up error….

    5. How much time daily, on the average did you devote to celestial?

    Probably about an hour, 30 min to several hours. I typically reduced two sights a day, sometimes none or more than two – depending on conditions. The sights themselves are pretty quick, 5, 10 minutes tops. Each reduction takes me about 10 – 15 minutes and the plot takes another ~10 minutes. One of the reasons I prefer noon sights is that they require less calculation and plotting – it’s not hard to take a series of sights, and calculate L and Lo with about 20 min of work: three 5 min sight collections and another 5 min pushing the pencil. Here’s an example used in the May workshop: https://drive.google.com/file/d/0Byo...ew?usp=sharing

    6. Based on your experience, can you quantify how much of a disadvantage is a competent celestial navigator to an equally well sailed identical boat with gps?

    That all depends on what your goal is. If you want to win the race then celestial navigation is definitely a distraction. The GPS gives you a fix at a glance; at best, celestial requires tens of minutes of real concentration (which is tough when you’re tired), and the extra effort doesn’t make you faster, and it’ll rarely be as accurate (though the accuracy doesn’t really matter much practically). If you like doing celestial, there isn’t a better opportunity than while sailing to HI. I’ve been studying celestial navigation for many years and had amused with it a few times during offshore deliveries. In 2012 I really wanted to practice the art while sailing alone. Honestly, I found it a relaxing distraction from repairs, routing and sail plan uncertainties. Corny as it sounds, I find observing the beauty in the sky to be deeply rewarding and uplifting. I’d sight Jupiter and then get out the binoculars and look at his moons…. The crisp clarity of our moon and planets, not to mention the milky way, captured my attention. It can be breathtaking. I think there is no better time at sea then on a clear glittering-sky night with the trades blowing, sailing (hopefully) between the dark squalls. And I get satisfaction from plotting an accurate two-body fix. But, in 2014 I decided to focus on weather and sailing rather than celestial, and concentrate on routing myself based on what I was seeing in the synoptics and offshore weather forecasts. I spent hours each day doing what-ifs. I think the time I spent poring over isobars and GRIBs made me a little faster. I can’t quantify the effect with any certainty because conditions are never the same in the race; 2012 and 2014 didn’t have the same weather. But it seems a safe bet that a focus on moving the boat to the finish line, rather than complicating the navigation task, will better your standing.

    7. Are you self-taught or professionally trained?

    Both. I started with as a DIY’er, then went through the USPS classes (through N). Then I helped teach the classes, and have also presented several seminars. I’m scheduled to lead an introductory one in Santa Barbara on 7 Oct, and everyone is welcome. https://drive.google.com/file/d/0Byo...ew?usp=sharing

    Steve

  8. #8
    Join Date
    Nov 2010
    Posts
    73

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    Steve,
    Well, I would give you an A plus on the quiz. Thank you so much for taking the time and effort to give such a detailed answer. You confirmed most of my suppositions. I did about three 500-600 mile passages across the Gulf of Mexico using celestial, which I taught myself, but never figured out how to do star and planet shots, although I could do sun, Polaris and lunar shots. I actually won my Class A in a Cozumel race in1978 using that limited knowledge when we had a total electrical system failure on the boat less then one day into a four day rase. It was my first use of celestial under fire. Then Loran C and GPS conspired to make me lazy.
    My latest boat I am putting together now is a 39 foot steel Spray replica, complete with gaff rig. It seems to me that I should revive my interest in Celestial to match my 200 year old yacht design, and when my personal circumstances allow me the time, to find a really long off-wind race to use my newly revived celestial skills to avoid sailing off the edge.
    JimB

  9. #9
    Join Date
    Jan 2012
    Location
    Santa Barbara Sometimes
    Posts
    166

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    Jim,

    Sounds like some great stories, and a lot of fun, thanks for sharing. FWIW, I find moon sights to be the most complicated. Good luck with your current projects, and let me know if you want help re-learning celestial.

    Steve

  10. #10
    Join Date
    Nov 2010
    Posts
    73

    Default

    Steve,
    I assume you use H.O. 249 when reducing sights? How do you get your exact time?---i.e.--do you use a timex, or a gimballed chronometer in a box that cost a few thousand bucks. What is your opinion of navigation calculators and/or software or spreadsheets that purport to shorten the time to reduce sights. Thanks.
    Jim

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