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/0ByoWPQ0Bj_ywWGVlbnhZanZLRkk/view?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/0ByoWPQ0Bj_ywdDdGYU1KZldJaVk/view?usp=sharing
Steve
