Another navagiation question

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Nice N Easy

I must admit that after the recent discourse on the caught in the fog thread, I am wondering what this post will bring. So, just for the sake of argument, her goes. You are sailing from Clearwater, Fl. to Port Mansfield, Tx. Your only nav. aids are your compass and your brain. You have NO electronics. No GPS, no Loran, no Radar, etc. The jetties at Port Mansfield are very short and low. Meaning difficult to see from any distance. There are no landmarks for approx. 100 miles either north or south, and no other inlet. And I do mean NO landmarks. Nothing but sand dunes that shift and change regularly. If you miss the inlet more than a mile or two, there is no way of knowing whether you are north or south of it. So, how would you navigate your boat to get into the inlet. I am really interested in hearing the responses of both the experienced and un experienced sailors on this board.
 
Jun 6, 2006
6,990
currently boatless wishing Harrington Harbor North, MD
Are we permitted to use a map(s)?

Otherwise I'm just guessing like a blind man with a Rubix cube.
 
Jun 6, 2006
6,990
currently boatless wishing Harrington Harbor North, MD
coast hop and DR

Assuming I get to use a map. I'd shoot for a landmark that I can be sure to find somewhat to the east of Port Mansfield. Then DR along the coast for the appropriate distance. Shortly before I arrive at Port Mansfield by DR I post everybody on deck with every eyeball looking for the jettys.
 

BobW

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Jul 21, 2005
456
Hunter 31 San Pedro, Ca
Well, let's see.....

If I have no charts AND no radio (you didn't say I had no radio) and I really HAD to make the trip, I'd set a course for Houston, which would take me past the mouth of the Mississippi. I don't think I'd miss Houston..... then I'd sail down the coast until I hit 100 miles of landmark-less coastline and start looking for what MUST be Port Mansfield. If I have no charts but DO have a radio, then I'm in a REAL quandry, because real men don't get lost, and real men don't ask directions...... but I think in this case I'd be willing to swallow my pride and check my position when I passed an oil rig or town or another boat. :) With a chart, but no radio, I'm gonna aim for Corpus Christi and follow the coast down. And if I'm halfway across the Gulf, WITH my radio, nav aids and charts, and suddenly they disappear...... well, I'm gonna sail NORTH! That direction means two critical things: 1. I WILL find land. 2. That land WILL be in the good ol' USA! (even Louisiana counts, doesn't it???) OK, can I have my GPS and chart plotter back.... pretty please??? You see, I'm NOT an old salt, and I appreciate modern tools...... gosh, I don't even own a typewriter anymore. ;D Cheers, Bob s/v X SAIL R 8
 
Jun 6, 2006
6,990
currently boatless wishing Harrington Harbor North, MD
OOPS

After down losding the maps from the USCG site and looking at them I see that Fort Mansfield is right on the southern tip of TX so instead of sailing to a point east of it I'd sail to a point north of it then DR south.
 
Dec 13, 2006
9
Catalina 28 North Padre Island, TX
A long trip to run aground

Port Mansfield cut presently has sandbars that reduce depth to four feet. So you could just run aground anywhere on this 300 mile barrier island. Or, sail to the marked entrance of the Corpus ship channel at Port Aransas. Then take a left and go south back 60 miles to Port Mansfield. Thirty years ago I sailed through Port Mansfield cut to borrow a soldering iron to repair my RDF which was my state-of-the-art navigation instrument. Rick
 
Jun 6, 2006
6,990
currently boatless wishing Harrington Harbor North, MD
Can I make my own tools while in route?

If I don't get to use a map then I'd sneak over to the library in Clearwater and find the Latitude of Port Mansfield and then sneak over to home depot and buy a tape measure. Then once under way I'd construct a device (the name escapes me) that the ancient south pacific sailors used. It is a length of twine with knots on it tied to a piece of wood. You put a knot in your teeth and stretch out the string holding the piece of wood so that one end is on the horizon facing north. Since I know that the altitude of the north star is equal to my latitude, if Polaris is above the stick I know I'm north of Port Mansfield's latitude and if Polaris is below the end of the stick I'm south. Simple high school trig (the tables are in my copy of Bowditch, I don't have to throw Bowditch overboard do I?) is all that is needed to calculate where to put the knot in the string. I'd still try for a spot north of Port Mansfield however as this would be the first time I tried this. If I hit my landmark dead on I might try to sail direct on a future trip. This is fun. I feel all salty already.
 
Aug 30, 2006
118
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Hable Anglais?

I would head for Brownsville, turn right when it gets shallow, take my first left, and Oh i forgot- throw the drugs overboard first.
 

Ross

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Jun 15, 2004
14,693
Islander/Wayfairer 30 sail number 25 Perryville,Md.
After some effort I was able to locate Port

Mansfield on chartviewer. There are two tanks shown on the chart and it is on the ICW There are marks for the channel and flash 2+1 8sec R 17 feet 4 mile light at the channel. I would enter the ICW at Corpus Christi and proceed south. Use chart 11304
 

higgs

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Aug 24, 2005
3,736
Nassau 34 Olcott, NY
What I would do

This is an offshore passage of over 600 miles. I think it would be foolish for me to attempt this type of passage w/o some type of navigational equipment. Since GPS is not available I would buy and learn how to use a sextant before even considering the passage. If i can't have a sextant and time to learn how to use it, I would head to Corpus Christy and follow the shore south from there. No electronics? Can I at least take my ipod?
 

Ross

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Jun 15, 2004
14,693
Islander/Wayfairer 30 sail number 25 Perryville,Md.
Even the earliest navigators depended on latitude

for finding destinations. So a sextant, backstaff, astrolabe or kamal would be essential otherwise you are just a blind man fumbling around in the dark.
 
M

Matthew

DR west, then skirt south

Being new, not good with all that gear you don't have, but raised on the Texas coast I vote for DR course 270 with a best guestimate of rate of progress built on knowing the feel of one's boat until you catch the lights of Corpus Christi. For me that's likely right at seven days. When you catch the lights, bear off south to about 240 and slow down as the water turns brown. Major issue is to get in sight of the barrier while still north of Port Mansfield. Then ease down the sand for what will be the last 15 to 30 miles. (Don't ever get to a place where you see sand without sand to the south of you and you know you are still north of Port Mansfield -- or at lease Brownsville.) Who knows if it would work, but I am fairly confident I could put the boat on Texas ground.
 
Aug 30, 2006
118
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Go West young man!

From eyeballing a world map, Clearwater and Corpus Christi are at the same latitude. Take your pick; i would rather aim a little south and turn north toward the US at the end.
 

Ross

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Jun 15, 2004
14,693
Islander/Wayfairer 30 sail number 25 Perryville,Md.
Between steering errors of 5 degrees and the

currents in the gulf you would do very well to make landfall within 50 miles of Corpus Christi. With no way to determine latitude you would be exporing with no way to record where you have been.
 

tweitz

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Oct 30, 2005
290
Beneteau 323 East Hampton, New York
Navigation

Makes you wonder how the explorers and seafarers of centuries past managed. They non only did not have GPS or radio, their compasses were shaky, they had no real chronometers until the early 19th century, and what passed for charts were worse than road maps.
 

higgs

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Aug 24, 2005
3,736
Nassau 34 Olcott, NY
Add to Ted and Ross

Ted - what you say is right on and is the reason it was not uncommen for our mariner forfathers to starve to death while trying to figure out where land was. Ross - right on, too. Another thing to consider if using DR for the entire trip is that in the 6 or seven days one would, especially in this region, expect a squall or two or more. One thing that a sailor can count on in going through a tough squall is being blown off course. If that squall hit early on the trip and blew one off course, that original compass heading would only magnify the error 500 miles later. Having a reasonably good idea of where you are at all times is absolutely vital. I would never point my boat in one direction and hope to be on course 5 days later.
 
Aug 30, 2006
118
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Agreed

It takes me longer to realize the effects of drift and a less than perfect steering, storms, etc. So at night just out of Clearwater, i'll aim for Polaris and make a mark on the mast in my sightline from standing at the wheel, and steer to that latitude if i'm off on the west end. What would be better?
 

BobW

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Jul 21, 2005
456
Hunter 31 San Pedro, Ca
Putting it together....

our fore-father-sailors often didn't get where they were wanting to go - witness Columbus? Also, much of the European sailing was either coastal, or headed in a known direction and destination, like from Rome to Egypt. You might miss, but you DID hit land. I guess it was a major accomplishment for the people who set out from South America headed west, but just HOW did they know there was ANYTHING out there? Hey, nice and easy, was this a test? How did we do? Cheers, Bob s/v X SAIL R 8
 
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