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    Re: Cel Nav!
    From: Robert Gainer
    Date: 2004 Jul 18, 14:37 +0000

    Mike;
    I think you would be very disappointed in practical navigation as done on
    the yachts. It�s not very precise.
    
    When I was a teenager I started sailing coastal on a 13-foot daysailor that
    my father and I built. On that boat the only time I used a sextant was to
    try it out. The results were such that I bought a taffrail log and
    binoculars instead of pursuing it. I later found out that the sextant was a
    stage prop from a High School in New Hampshire. I sailed as far as Canada
    with just a compass and taffrail log.
    
    When I decided to sail trans-Atlantic in a 22� Sea Sprite it was obvious
    that a sextant was going on that trip. I talked to someone in Providence
    Rhode Island that was preparing for his first crossing and among other thing
    navigation was discussed. His theory was that it would take at least 30 days
    to get near any land and he would take a sextant and a book on how to use
    it. In his spare time before landfall he could teach himself all he needed
    to know. He had a taffrail log and that would provide a double check on when
    to start looking for land. I gather that he learned how to do the sight and
    the steps necessarily to reduce it and plot the answer. Unfortunately he
    didn�t know when he departed that you need a nautical almanac and tables to
    work out any thing other then the sample problems in the book. The taffrail
    log was almost right on, but he still run up on the Channel Islands in the
    night. The boat was a total loss.
    
    After that, a quick study of celestial navigation was definitely in the
    plan. I learned 211 (Ageton), 229 and 249. I did not consider Lunar Distance
    as a possibility at that time. I selected H.O. 211 because on a 22 foot boat
    the physical size of the tables made a difference. I used a 13-dollar (at
    that time) Davis sextant and Timex wristwatch. The trip itself was a
    testament to the preparation, nothing of much note happened.
    
    A couple of thing that makes for good times at the yacht club bar did
    happen. On the Grand Banks I came on deck about 0100 hours and saw a
    searchlight pointing my way from the east and I thought that a ship that was
    part of the fishing fleet was coming my way. After 5 min or so the bearing
    to the light did not change. 5 more min and the bearing did not change. 3 or
    4 min more and I changed my self-steering to pass to the south of the ship.
    The bearing still did not change. I turned on my cabin and spreader lights.
    Still no change. The search light from that ship just got larger brighter
    and higher. I now made a 90-degree turn to the south and called to that ship
    on my vhf. Still no change. Still that light just got larger, brighter and
    higher. Panic was at hand, but then I saw the light rise up and out of the
    mist. It was the moon rising in the east. I did not enter this into my log.
    At the time I did not want anyone to know how stupid I was. At this stage in
    my life everyone already knows how stupid I am so I tell the story now. The
    mist on the Grand Banks meant that with my height of eye there was a large
    amount of time that no horizon was available to me. In fact on that boat my
    height (6 feet) of eye was so low that any kind of weather made it hard to
    get a shot.
    
    I few hundred miles from England a ship stopped by to see if I was where I
    wanted to be. After explaining that I was going to England and not just lost
    they asked if I needed anything and went on their way. Before going they
    gave me a check on my position and it turned out that the latitude was very
    close but the longitude was off by something in the order of 20 miles. What
    you hear about Timex watches is true, the Timex watch that I was using took
    a licking and kept on ticking, just not an accurate tick. I now use a
    electronic chronometer with a radio for a time check. The wind was not very
    cooperative that summer and one week later the same ship stopped by again.
    After exchanging pleasantries they asked why I wanted to stay offshore
    instead of finishing the trip. I told them I wanted to finish the trip but
    the lack of wind had an effect. In the week they had reached there
    destination, unloaded and reloaded and my boat had moved only 75 miles. A
    few days later I made landfall after 59 days at sea. I was � nautical mile
    north of Bishop Rock Light when I was shooting to get � south of the Light.
    
    That trip was done with a Davis sextant made of plastic. I think the precise
    landfall makes a good story but it was just luck. The plastic sextant can be
    read to the nearest minute and the scale has an error of up to 7 minutes.
    Add to this, the motion of a boat that small makes me suspect that seven to
    eleven miles is about all you can hope for in day to day use. After that
    trip I got a Freiberger, which I used for over ten years with great success.
    I lent that out to a friend who unfortunately had a motorcycle accident and
    died. His family thought that it was one of his things and there was no way
    I was going to say anything. I bought another Freiberger. I have now
    replaced my Freiberger with a Cassens & Plath sextant. The better sextant
    does give me a better result. Among the yachtsmen this is a hot topic for
    debate. Many clam that the precision that you can archive with the sight is
    such that the accuracy of the instrument doesn�t matter. I now have had over
    30 years experience at this and find that on a good day with the Cassens &
    Plath I can get within 6 or 7 tenths of a mile and with the plastic sextant
    only within 2 miles or so.
    
    I then got an Allied built Chance 30/30. It was a great boat to sail but had
    a few problems offshore if you get into very bad weather. Admittedly you
    wouldn�t make it a habit to sail in a hurricane but it gives you a very good
    idea of what a boat is capable of in cruising.
    
    In October of 1976 I was in Hurricane Gloria with 90 Knots wind speed and 45
    foot (or better, its hard to tell) waves. Just to the north of me was the
    590 foot 15,028 ton Sylvia L
    Ossa with a crew of 37. She sank with a loss of all hands sometime between
    the 13 to the 15 of October. During the height of the storm the truck
    fitting failed by cracking between the hole for the headstay clevis pin and
    the corner of the casting adjacent to the mast. The loss of the headstay was
    to say the least very awkward at that time. In trying to turn the boat
    downwind after the headstay went the rudderstock failed at the bottom of the
    bolt under the tiller and the stock sheared off.
    
    Within the next hour the motion of the boat was so violent that the hull
    failed with a crack forming between the aft most keel bolts. You could see
    the sides of the crack moving up and down as the boat rolled. She started to
    make water at that point. After getting beat up for that hour I had the boat
    back under control and hove to. Before the storm was fully over the steering
    was repaired and a new
    head stay was up. The leak was getting bad so I started for the nearest dry
    land as fast as I could go.
    At this point Hurricane Holly was predicted to be coming my way. I had
    enough of bad weather so I sent out a Mayday by SSB and a Dutch tugboat
    received that, they relayed it to the German ship Hagen of the Hapag-Lloyd
    line. She had passed me in the night some 100 miles to the west but she
    turned around and came back to get me. We both had RDF equipment and tried
    to get a bearing on each other with a long count. Both of us get
    inconsistent results.
    
    During the morning of the rescue I got a few quick shots of the sun. I
    picked the one that felt best and plotted that. The navigator on the Hagen
    and I compared notes and decided that the Hagen was very close to the LOP
    that I had and that they would run down that line and see what they could
    find. I must have been close because that worked and we got together. Again
    because of the conditions I think that was just luck. With luck you make it
    and without you don�t get to send letters to the navigation list. When she
    got to me the wind was climbing and had reached 60 knots.
    
    When my boat came alongside the Hagen the crack at the aft two keel bolts
    propagated along the entire length of the keel. The bottom of the boat
    flexed downward and opened up at the bolts and she started to sink. In the
    hour so before we meet we spoke by VHF and they asked for the dimensions and
    weight of the boat. There plan was to weld a cradle to the deck and if they
    could they wanted to pick up the boat with two wire slings and swing her
    inboard to the steel cradle. When we did get together the captain kept his
    ship away from my boat a few feet and had two of his crew come onboard with
    wire cutters, they helped me off and then cut the standing rigging while
    some crew on deck held the mast. They brought the rig on deck and on the
    next roll she was out of the water.
    I don�t think she hit the ship but once during the entire time. That one
    strike crushed about ten feet of hull-deck joint. I had been beat up so much
    from going up the mast to rig a headstay that I couldn�t walk and that�s why
    I needed help to get off my boat. The entire rescue was over in fewer than
    ten minuets and they never came to a full stop.
    
    The bottom line is the keel area of the boat is not strong enough and the
    rudderstock needs to be solid instead of heavy wall tubing. When the boat
    was on deck I found that the fairing forward of the rudder had also failed
    and the keel had dropped over 1/2 inch by digging out the fiberglass under
    the washers for the keel bolts. Other then that I thought the boat was
    great.
    
    I have had many other trips both Trans-Atlantic and coastwise delivery
    trips. For the most part they are very straightforward and not too exciting.
    For excitement I have been on a sinking commercial ship and mid Atlantic on
    a 27 foot Vega that caught on fire. I have sailed the Bay of Biscay in the
    wintertime (the spray froze on the sextant) on a 100-ton gaff-rigged ketch
    that was over 100 years old. But as they say �a dull trip is the hallmark of
    good seamanship�. If you need some specific information instead of just same
    ramblings about sailing just ask.
    Robert Gainer
    
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