Hey Howard, I think I talked to that same guy when I was looking for a 17. He was totally unprepared for that attempted crossing! He would have just disappeared without a trace if he hadn't turned back. Mark M23 & M15 former M17 too On Dec 4, 2014 2:47 PM, "Howard Audsley" <haudsley@tranquility.net> wrote:
I purchased my M17 from a gent who set off from San Francisco towards Hawaii. His ONLY means of navigation was one hand held GPS unit. Not sure if he had any paper charts, but he did not have a sextant, so if the GPS gave out, was lost overboard or otherwise put out of commission, not sure how he was going to find Hawaii. That is a big place to wander around looking for such a tiny spec of land. Lucky for him he turned back after 4 or 5 days, so it never became an issue.
Anyway, yet another solution to one GPS and a sextant is several cheap GPS units. Two or three of them combined are less expensive than a sextant, but do the same thing. Leave the spares and fresh batteries safely stashed in the box until you need them.
BTW, I use an older Garmin GPS chart plotter with depth finder built in. So in addition to knowing where I am, I know how much water is beneath me. Mine also has the nifty feature of tide tables built in. On tidal waters, that is more handy than you might think.
But like the others, I still don't venture far on unfamiliar waters without paper charts. I pay as much attention to them as the GPS.
On Dec 4, 2014, at 3:37 PM, Thomas Buzzi wrote:
Hi Connie, Thanks for the added info. I finally get the idea of how a chronometer works using GMT. If your onboard timepiece associates hours with 15 degrees west long then wherever you are at noon GMT is...... humm, lost it. Oh, you have to measure the height of the sun at your present position to tell you the degree long. to plot on your chart. Somehow. Too bad we don't live closer. I have always wanted to learn how to use a sextant but reading the information just never sunk in. Oh well, I can get a hand bearing compass and some local charts. Sounds like fun and a good feeling to know where I am even if the gps quits. Tom B
On Thu, Dec 4, 2014 at 3:11 PM, Conbert Benneck <chbenneck@gmail.com> wrote:
On 12/4/2014 2:01 PM, Thomas Buzzi wrote:
Tom
I also can highly recommend the Dava Sobel book on "Longitude".
She describes the basic problem that mariners had determining longitude, and then tells the story of how the British Government put up a prize for anyone who could make an accurate chronometer. The Government was pressured to do this because of all the naval and merchant ships that were lost as a result of not having an accurate way to establish longitude reliably.
If you divide the earth's circumference of 360 degrees by 24 hours, your answer shows you that the earth rotates 15 degrees per hour.
Wherever you may be on the surface of the earth, the sun rises, climbs to its meridian at what navigators call Local Apparent Noon (LAN) at your location, and then starts descending again.
If you had an accurate time piece set to Greenwich Mean Time, and the time pieces' error rate was constant, then knowing that, and the time of your LAN it is a very simple math problem to determine how far West or East of Greenwich you are located at that specific moment
If you measure the height of the sun at that point; and note the exact time of the observation, in seconds; minutes; and hours, you can now establish your longitudinal position (dependent on the accuracy of your measurements). You have to do it in that order since each second counts in the calculation, and accuracy of time of observation is critical. Seconds change rapidly, minutes only 60 seconds later....
Example: New York City is roughly at 75 degrees W Longitude from 0 degree Greenwich, England. Divide 75 degrees by 15 (the degrees in an hour) and you will see that New York's geographical position is 5 hours West of Greenwich.
This goes on until you reach the 180th degree West, called the International Date Line, which is located in the Pacific Ocean.
When you reach the International Date Line heading West from the USA, it is Thursday; but once you have crossed the Date Line it becomes Friday, and the beginning of a new day for the 180 degree East of Greenwich area of the world.
-------------------------------
Last thought: If a salt water wave or spray hits my sextant I can just rinse it off with fresh water and dry it with a towel and it keeps working (with a drop of oil in the mechanism once in awhile) Gin also will do the job, but I don't think my rinse solutions will work for electronics.... They are nice toys and give you pretty pictures but don't trust your life or the safety of your boat to them. They are only a secondary source of information.
Learn to do dead reckoning navigation the classical way, and you will always be safe.
Connie
thanks to all that took the time to share their ideas about this. I have a
pretty good idea of what course to take. I also have a lead on a what sounds like a very interesting book. Fair winds, Tom B, Mont 17 #258
Yes, when he bought the M-17, I took him out for a test sail, we had a nice conversation about pocket cruisers, he told me that he almost bought a Victoria 18 before finding my M-17, but the guy wouldn't sell it to him. The wind was breezing up on our test sail, which it does here in Kansas, I reefed the boat, showed him how to heave-to, he showed good interest in how each of these procedures worked. We agreed upon a price, he brought me cash, and THEN he told me a: that he hadn't been sailing before our test drive, and B: he planned to trailer the boat to Half Mooon Bay, spend 3 weeks learning how to sail, and to then head for Hawaii. 2 months later, I ran into his sister-in-law's husband, who told me that the guy had spent the 3 weeks learning, and headed west. After 3 days out, his having not taught himself how to self steer meant that he couldn't, and hadn't slept. He turned around, drove the boat back to KS, and sold it to Howard! Thomas Howe 785-550-1169 -----Original Message----- From: montgomery_boats [mailto:montgomery_boats-bounces@mailman.xmission.com] On Behalf Of Mark Dvorscak Sent: Thursday, December 04, 2014 6:54 PM To: For and about Montgomery Sailboats Subject: M_Boats: Howard's salt water 17 Hey Howard, I think I talked to that same guy when I was looking for a 17. He was totally unprepared for that attempted crossing! He would have just disappeared without a trace if he hadn't turned back. Mark M23 & M15 former M17 too On Dec 4, 2014 2:47 PM, "Howard Audsley" <haudsley@tranquility.net> wrote:
I purchased my M17 from a gent who set off from San Francisco towards Hawaii. His ONLY means of navigation was one hand held GPS unit. Not sure if he had any paper charts, but he did not have a sextant, so if the GPS gave out, was lost overboard or otherwise put out of commission, not sure how he was going to find Hawaii. That is a big place to wander around looking for such a tiny spec of land. Lucky for him he turned back after 4 or 5 days, so it never became an issue.
Anyway, yet another solution to one GPS and a sextant is several cheap GPS units. Two or three of them combined are less expensive than a sextant, but do the same thing. Leave the spares and fresh batteries safely stashed in the box until you need them.
BTW, I use an older Garmin GPS chart plotter with depth finder built in. So in addition to knowing where I am, I know how much water is beneath me. Mine also has the nifty feature of tide tables built in. On tidal waters, that is more handy than you might think.
But like the others, I still don't venture far on unfamiliar waters without paper charts. I pay as much attention to them as the GPS.
On Dec 4, 2014, at 3:37 PM, Thomas Buzzi wrote:
Hi Connie, Thanks for the added info. I finally get the idea of how a chronometer works using GMT. If your onboard timepiece associates hours with 15 degrees west long then wherever you are at noon GMT is...... humm, lost it. Oh, you have to measure the height of the sun at your present position to tell you the degree long. to plot on your chart. Somehow. Too bad we don't live closer. I have always wanted to learn how to use a sextant but reading the information just never sunk in. Oh well, I can get a hand bearing compass and some local charts. Sounds like fun and a good feeling to know where I am even if the gps quits. Tom B
On Thu, Dec 4, 2014 at 3:11 PM, Conbert Benneck <chbenneck@gmail.com> wrote:
On 12/4/2014 2:01 PM, Thomas Buzzi wrote:
Tom
I also can highly recommend the Dava Sobel book on "Longitude".
She describes the basic problem that mariners had determining longitude, and then tells the story of how the British Government put up a prize for anyone who could make an accurate chronometer. The Government was pressured to do this because of all the naval and merchant ships that were lost as a result of not having an accurate way to establish longitude reliably.
If you divide the earth's circumference of 360 degrees by 24 hours, your answer shows you that the earth rotates 15 degrees per hour.
Wherever you may be on the surface of the earth, the sun rises, climbs to its meridian at what navigators call Local Apparent Noon (LAN) at your location, and then starts descending again.
If you had an accurate time piece set to Greenwich Mean Time, and the time pieces' error rate was constant, then knowing that, and the time of your LAN it is a very simple math problem to determine how far West or East of Greenwich you are located at that specific moment
If you measure the height of the sun at that point; and note the exact time of the observation, in seconds; minutes; and hours, you can now establish your longitudinal position (dependent on the accuracy of your measurements). You have to do it in that order since each second counts in the calculation, and accuracy of time of observation is critical. Seconds change rapidly, minutes only 60 seconds later....
Example: New York City is roughly at 75 degrees W Longitude from 0 degree Greenwich, England. Divide 75 degrees by 15 (the degrees in an hour) and you will see that New York's geographical position is 5 hours West of Greenwich.
This goes on until you reach the 180th degree West, called the International Date Line, which is located in the Pacific Ocean.
When you reach the International Date Line heading West from the USA, it is Thursday; but once you have crossed the Date Line it becomes Friday, and the beginning of a new day for the 180 degree East of Greenwich area of the world.
-------------------------------
Last thought: If a salt water wave or spray hits my sextant I can just rinse it off with fresh water and dry it with a towel and it keeps working (with a drop of oil in the mechanism once in awhile) Gin also will do the job, but I don't think my rinse solutions will work for electronics.... They are nice toys and give you pretty pictures but don't trust your life or the safety of your boat to them. They are only a secondary source of information.
Learn to do dead reckoning navigation the classical way, and you will always be safe.
Connie
thanks to all that took the time to share their ideas about this. I have a
pretty good idea of what course to take. I also have a lead on a what sounds like a very interesting book. Fair winds, Tom B, Mont 17 #258
Don't mean to beat up on a guy who had a dream that didn't pan out........but he really was wise to turn back. As he told me, the only food he had on board was dry rice. He had water, but it didn't sound like he had enough to make a trip of that distance, and no way of making more. His only sails were the original Reggie Armstrong main, with one reef point; the working jib and 150 genny........all original (1978 in about 2002). And as Thomas mentions, no self steering. If there is a point to all this, it may be to realize that while a well prepared boat might be capable of such a trip, the skipper better be up to it and prepared as well. That is probably good advice for anyone venturing too far from shore. I got lost once in fog so thick I could hardly see the front of the boat, and I was only 100 yards or so from the dock. I finally anchored until the fog lifted. Have not left a dock since without at least a hand held compass on board. On Dec 5, 2014, at 11:15 AM, Thomas Howe wrote:
Yes, when he bought the M-17, I took him out for a test sail, we had a nice conversation about pocket cruisers, he told me that he almost bought a Victoria 18 before finding my M-17, but the guy wouldn't sell it to him. The wind was breezing up on our test sail, which it does here in Kansas, I reefed the boat, showed him how to heave-to, he showed good interest in how each of these procedures worked. We agreed upon a price, he brought me cash, and THEN he told me a: that he hadn't been sailing before our test drive, and B: he planned to trailer the boat to Half Mooon Bay, spend 3 weeks learning how to sail, and to then head for Hawaii. 2 months later, I ran into his sister-in-law's husband, who told me that the guy had spent the 3 weeks learning, and headed west. After 3 days out, his having not taught himself how to self steer meant that he couldn't, and hadn't slept. He turned around, drove the boat back to KS, and sold it to Howard!
Thomas Howe 785-550-1169
-----Original Message----- From: montgomery_boats [mailto:montgomery_boats-bounces@mailman.xmission.com] On Behalf Of Mark Dvorscak Sent: Thursday, December 04, 2014 6:54 PM To: For and about Montgomery Sailboats Subject: M_Boats: Howard's salt water 17
Hey Howard, I think I talked to that same guy when I was looking for a 17. He was totally unprepared for that attempted crossing! He would have just disappeared without a trace if he hadn't turned back. Mark M23 & M15 former M17 too On Dec 4, 2014 2:47 PM, "Howard Audsley" <haudsley@tranquility.net> wrote:
I purchased my M17 from a gent who set off from San Francisco towards Hawaii. His ONLY means of navigation was one hand held GPS unit. Not sure if he had any paper charts, but he did not have a sextant, so if the GPS gave out, was lost overboard or otherwise put out of commission, not sure how he was going to find Hawaii. That is a big place to wander around looking for such a tiny spec of land. Lucky for him he turned back after 4 or 5 days, so it never became an issue.
Anyway, yet another solution to one GPS and a sextant is several cheap GPS units. Two or three of them combined are less expensive than a sextant, but do the same thing. Leave the spares and fresh batteries safely stashed in the box until you need them.
BTW, I use an older Garmin GPS chart plotter with depth finder built in. So in addition to knowing where I am, I know how much water is beneath me. Mine also has the nifty feature of tide tables built in. On tidal waters, that is more handy than you might think.
But like the others, I still don't venture far on unfamiliar waters without paper charts. I pay as much attention to them as the GPS.
On Dec 4, 2014, at 3:37 PM, Thomas Buzzi wrote:
Hi Connie, Thanks for the added info. I finally get the idea of how a chronometer works using GMT. If your onboard timepiece associates hours with 15 degrees west long then wherever you are at noon GMT is...... humm, lost it. Oh, you have to measure the height of the sun at your present position to tell you the degree long. to plot on your chart. Somehow. Too bad we don't live closer. I have always wanted to learn how to use a sextant but reading the information just never sunk in. Oh well, I can get a hand bearing compass and some local charts. Sounds like fun and a good feeling to know where I am even if the gps quits. Tom B
On Thu, Dec 4, 2014 at 3:11 PM, Conbert Benneck <chbenneck@gmail.com> wrote:
On 12/4/2014 2:01 PM, Thomas Buzzi wrote:
Tom
I also can highly recommend the Dava Sobel book on "Longitude".
She describes the basic problem that mariners had determining longitude, and then tells the story of how the British Government put up a prize for anyone who could make an accurate chronometer. The Government was pressured to do this because of all the naval and merchant ships that were lost as a result of not having an accurate way to establish longitude reliably.
If you divide the earth's circumference of 360 degrees by 24 hours, your answer shows you that the earth rotates 15 degrees per hour.
Wherever you may be on the surface of the earth, the sun rises, climbs to its meridian at what navigators call Local Apparent Noon (LAN) at your location, and then starts descending again.
If you had an accurate time piece set to Greenwich Mean Time, and the time pieces' error rate was constant, then knowing that, and the time of your LAN it is a very simple math problem to determine how far West or East of Greenwich you are located at that specific moment
If you measure the height of the sun at that point; and note the exact time of the observation, in seconds; minutes; and hours, you can now establish your longitudinal position (dependent on the accuracy of your measurements). You have to do it in that order since each second counts in the calculation, and accuracy of time of observation is critical. Seconds change rapidly, minutes only 60 seconds later....
Example: New York City is roughly at 75 degrees W Longitude from 0 degree Greenwich, England. Divide 75 degrees by 15 (the degrees in an hour) and you will see that New York's geographical position is 5 hours West of Greenwich.
This goes on until you reach the 180th degree West, called the International Date Line, which is located in the Pacific Ocean.
When you reach the International Date Line heading West from the USA, it is Thursday; but once you have crossed the Date Line it becomes Friday, and the beginning of a new day for the 180 degree East of Greenwich area of the world.
-------------------------------
Last thought: If a salt water wave or spray hits my sextant I can just rinse it off with fresh water and dry it with a towel and it keeps working (with a drop of oil in the mechanism once in awhile) Gin also will do the job, but I don't think my rinse solutions will work for electronics.... They are nice toys and give you pretty pictures but don't trust your life or the safety of your boat to them. They are only a secondary source of information.
Learn to do dead reckoning navigation the classical way, and you will always be safe.
Connie
thanks to all that took the time to share their ideas about this. I have a
pretty good idea of what course to take. I also have a lead on a what sounds like a very interesting book. Fair winds, Tom B, Mont 17 #258
participants (3)
-
Howard Audsley -
Mark Dvorscak -
Thomas Howe