So I'm here in Seattle working on my boat, making plans for trips with a choice of thousands of miles of beautiful coastline. I'm planning a 10 day trip in June and then a six week vacation in August/Sept. There are lots of choices - the difficulty is what to leave out, not searching for something that I want to see.
The same would be true in most areas of the world. Coastline is beautiful and teeming with life. Its also fragile.
Watching what's happening in the Gulf right now is pretty sad. Its also making me angry. There seem to be plenty of mistakes happening and the costs of the mistakes may be paid for years and years. I'm not an expert on anything oil related, but there are people who are experts. Relying on one company to stop and fix this thing seems naive - its not their Gulf, its all of ours.
If you're not angry about what's happening down there yet, here's a video which might help you along that path. Caution, it contains foul language.
If you still aren't angry, here are two more related stories.
BP blocking journalists from spill sites
3 million feet of boom in Gulf, but does it help?
Friday, May 28, 2010
Monday, May 17, 2010
A single handed weekend
I'm back from a beautiful weekend of sailing. Blue skies, fairly warm, and even a little bit of wind thrown in there.
I left early friday evening for Blakeley Harbor to anchor out. There was a nice wind on friday, 5-10 knots from the north so I had an easy downwind sail. Blue skies, easy sailing, things were pretty nice. I've sailed single handed before so nothing really new so far, more good practice though. Anchoring single handed went pretty well. There are times when having more people aboard would be very handy - but I'm trying to develop these skills and the only way I can see myself learning this stuff is by doing it. When there are others aboard things just happen and you aren't forced to think through how you would do it if you were sailing by yourself. Anyway, friday ended well, safely at anchor, clear skies, lots of stars.
Saturday morning I had to figure out raising the anchor while staying safe in the anchorage. There was a little over 5 knots of breeze blowing through so it wasn't a huge challenge and it went well in these conditions. I like to spray down the chain as it comes up to keep mud out of the anchor locker, so I was on the bow spraying, raising the anchor, stopping to walk back to the helm to maneuver the boat, back to the bow to raise more chain, down below to spread the chain around as it castled, back to the helm, back to the bow... It was pretty smooth. It it had been blowing 20 knots or more it would have been more of a challenge.
I got out to Puget sound with the idea of heading south to Quartermaster harbor...but there was no wind. I'm pretty patient so I waited for four hours with the sails up bobbing around while I drifted first north and then south with the current, watching the current go from an ebb to a flood. Finally I'd had enough and motored back to Blakeley for a repeat. This time I lowered the chain from the windlass remote rather than being at the bow and unleashing the chain from the windlass clutch. When using the clutch I can lower chain very quickly - it can just rip out of the locker. That could be handy, but I'm not at the helm when doing it. Using the remote the Lighthouse lowers chain much more slowly, but its controllable as I can maneuver at the same time. I'll try both of these approaches again, it might be that I use them in different circumstances. When I finished anchoring it was still early so I waxed the topsides for a while, cleaned things up, read, enjoyed the sun, had dinner and just generally enjoyed being out.
Sunday morning I had a small inspiration for making raising the anchor easier. I fastened the hose nozzle to the bow of the boat pointing down at the chain. I was then able to use the windlass remote to raise the whole rode, stopping once to reflake the chain below - but this was done while the anchor was still on the ground so I wasn't moving anywhere. It was pretty smooth. As the anchor tore free I was able to get it to the bow and then head very slowly forward with the autopilot on while I moved around cleaning things up and getting ready for a sail. I'll work on making the hose nozzle/bow connection easier and try it some more. If only I could see the chain rode at the bow from the helm, that would make placing the boat as the chain came up easier. Maybe some sort of mirror setup would help with that?
Getting back out to the sound there was again no wind. I motored slowly toward Shilshole and after about 1/2 hour a few knots of wind arrived. I let the genoa out and started sailing at about a knot north! The wind slowly filled in to between 10 and 15 N, which is more than enough to drive the boat at hull speed. Sweet!
I left early friday evening for Blakeley Harbor to anchor out. There was a nice wind on friday, 5-10 knots from the north so I had an easy downwind sail. Blue skies, easy sailing, things were pretty nice. I've sailed single handed before so nothing really new so far, more good practice though. Anchoring single handed went pretty well. There are times when having more people aboard would be very handy - but I'm trying to develop these skills and the only way I can see myself learning this stuff is by doing it. When there are others aboard things just happen and you aren't forced to think through how you would do it if you were sailing by yourself. Anyway, friday ended well, safely at anchor, clear skies, lots of stars.
Saturday morning I had to figure out raising the anchor while staying safe in the anchorage. There was a little over 5 knots of breeze blowing through so it wasn't a huge challenge and it went well in these conditions. I like to spray down the chain as it comes up to keep mud out of the anchor locker, so I was on the bow spraying, raising the anchor, stopping to walk back to the helm to maneuver the boat, back to the bow to raise more chain, down below to spread the chain around as it castled, back to the helm, back to the bow... It was pretty smooth. It it had been blowing 20 knots or more it would have been more of a challenge.
I got out to Puget sound with the idea of heading south to Quartermaster harbor...but there was no wind. I'm pretty patient so I waited for four hours with the sails up bobbing around while I drifted first north and then south with the current, watching the current go from an ebb to a flood. Finally I'd had enough and motored back to Blakeley for a repeat. This time I lowered the chain from the windlass remote rather than being at the bow and unleashing the chain from the windlass clutch. When using the clutch I can lower chain very quickly - it can just rip out of the locker. That could be handy, but I'm not at the helm when doing it. Using the remote the Lighthouse lowers chain much more slowly, but its controllable as I can maneuver at the same time. I'll try both of these approaches again, it might be that I use them in different circumstances. When I finished anchoring it was still early so I waxed the topsides for a while, cleaned things up, read, enjoyed the sun, had dinner and just generally enjoyed being out.
Sunday morning I had a small inspiration for making raising the anchor easier. I fastened the hose nozzle to the bow of the boat pointing down at the chain. I was then able to use the windlass remote to raise the whole rode, stopping once to reflake the chain below - but this was done while the anchor was still on the ground so I wasn't moving anywhere. It was pretty smooth. As the anchor tore free I was able to get it to the bow and then head very slowly forward with the autopilot on while I moved around cleaning things up and getting ready for a sail. I'll work on making the hose nozzle/bow connection easier and try it some more. If only I could see the chain rode at the bow from the helm, that would make placing the boat as the chain came up easier. Maybe some sort of mirror setup would help with that?
Getting back out to the sound there was again no wind. I motored slowly toward Shilshole and after about 1/2 hour a few knots of wind arrived. I let the genoa out and started sailing at about a knot north! The wind slowly filled in to between 10 and 15 N, which is more than enough to drive the boat at hull speed. Sweet!
Thursday, May 13, 2010
Another project done
The sound deadening in the engine compartment is done.
I ripped out all the old material from the engine compartment which was disintegrating and causing a god awful mess. Then came the tedious cleaning to get back to plain wood or gel coat, removing all the old adhesive.
The new sound deadening panels are from Sailors Solutions and come in 1 foot x 1 foot panels, with adhesive on one side and heavy silver film on the other. Installing the panels was a breeze compared to some of the things I've done this winter! Running the engine with the new panels in place is much better - the high frequency annoying noises are gone. I can still hear the lower frequency thrumming - I've got a 4 cylinder diesel engine in the boat, its not exactly going to go away. But I no longer have blood dripping from my ears after running it for a while.
Looking at my list of projects now is pretty satisfying. There just isn't that much left on it that is major. I need to varnish the cabin sole. Someday. Maybe next winter. I need to varnish the exterior teak where the old varnish is flaking off. But maybe I can hire someone to do that with me. Then there are a bunch of smaller things, like getting the equipment for climbing the mast together and figuring out a good jibe preventer setup, etc, etc. When I start getting setup for offshore sailing my list will grow again, but that can wait for a while. I'll be doing coastal sailing this summer, and the boat is setup for that.
Time to sail more! If it was a 80/20 rule before, with 80% of the time spent doing projects and 20% sailing, it should be something more like a 60/40 rule now, with 60% going sailing.
Finally! Its a sailboat not a project. Lets go sailing!
I ripped out all the old material from the engine compartment which was disintegrating and causing a god awful mess. Then came the tedious cleaning to get back to plain wood or gel coat, removing all the old adhesive.
The new sound deadening panels are from Sailors Solutions and come in 1 foot x 1 foot panels, with adhesive on one side and heavy silver film on the other. Installing the panels was a breeze compared to some of the things I've done this winter! Running the engine with the new panels in place is much better - the high frequency annoying noises are gone. I can still hear the lower frequency thrumming - I've got a 4 cylinder diesel engine in the boat, its not exactly going to go away. But I no longer have blood dripping from my ears after running it for a while.
Looking at my list of projects now is pretty satisfying. There just isn't that much left on it that is major. I need to varnish the cabin sole. Someday. Maybe next winter. I need to varnish the exterior teak where the old varnish is flaking off. But maybe I can hire someone to do that with me. Then there are a bunch of smaller things, like getting the equipment for climbing the mast together and figuring out a good jibe preventer setup, etc, etc. When I start getting setup for offshore sailing my list will grow again, but that can wait for a while. I'll be doing coastal sailing this summer, and the boat is setup for that.
Time to sail more! If it was a 80/20 rule before, with 80% of the time spent doing projects and 20% sailing, it should be something more like a 60/40 rule now, with 60% going sailing.
Finally! Its a sailboat not a project. Lets go sailing!
Thursday, April 22, 2010
Celestial Navigation!
I attended a celestial navigation course at Windworks over the April 10th weekend. Everybody knows that celestial navigation is used to figure out where you are when your at sea, right? You use the sextant to measure an angle and then do a bunch of math and voila, now you know where you are!
I understood that overview but never really understood what was really going on. Now I know!
A general overview of celestial navigation is really pretty easy. Don't be confused by my description - its probably much easier than it sounds!
All sailors should know how to do simple navigation. One of the easy things to do when sailing around coastlines is to get a fix for where you are by taking three bearings to landmarks. For example, if you know roughly where you are, look at a chart to pick three things you will be able to see. A lighthouse, a radio tower and the end of a point of land. Go onto deck with a hand bearing compass and record the bearings to each of these three marks. Then go back to your chart and draw lines from the marks along the bearings you measured and the three lines will cross in some small area - that's where you are.
Celestial navigation is basically the same thing. The most basic form is where you pick three stars which will be visible and arranged around the horizon roughly equally. Then you go up on deck with your sextant and take a measurement and record the time. With some basic math (addition and subtraction) and table lookups, you can then end up with three lines of position (LOPs) which will intersect in a small area. The area of intersection is where you are. Its the same as for taking a fix with a compass but with more math.
Its pretty cool.
For a star, the basic idea is that the stars have well known positions in the sky at any particular time. This can all be found by looking it up in tables and doing a little math. After doing this math you end up with the geographic position of the star at that exact time - essentially the point on earth which is directly below the star right then. The next step is to assume that you are at some point, your assumed position. This can be done by estimating where you think you are by dead reckoning. If you're far out its ok, that will be fixed a little bit later. Now comes the magic of the sight reduction tables. Given the geographic position of a star, and your assumed position you can easily calculate a bearing to the star and its exact expected height above your horizon. That part of the calculation is mainly done as table lookups and is a little magic.
So what you do is pick a star (or three) from the tables which you want to measure. Then go onto deck and find the star and then measure the angle between it and the horizon with the sextant. A sextant really only does one thing - it measures angles very precisely. When you measure the angle you also record the time. Then you make an assumption for where you think you are and do the calculation to find where the star was expected to be at that exact time. Once that is done, you have two angles: the height of the star where it was expected to be and the height of the star in reality. The difference between these two angles relates to how far away from your assumed point you are.
Hold your arm up for this next part: if the height of the star was expected to be 45 deg above the horizon (hold your arm out at 45 degrees) but was measured to be 30 degrees (slide your arm down to 30 degrees) then: are you closer or further away from the geographic position of the star? After a bit of thought and repeated arm gestures, the answer comes: you are further away! If the angle measured was greater than the expected angle then you are closer to the star's geographic position than you thought.
So almost done now. You have an assumed position and a bearing to the star at the exact time you measured the star. Draw a line on a chart from where you are to the star. Now adjust your assumed point toward or away from the star by the amount corresponding to the difference in the two angles (the computed angle and the measured angle.) Make a mark on the chart at that point. For example, given your assumed position, the bearing to the star (its azimuth) might be 230 degrees and you are 3.5 miles further away - so put a new mark at that point. You aren't at that point, that would be too easy. So what does that point indicate?
To understand what you just did, think of a streetlight. The geographic position of the streetlight is the point just below the light (for a star its the point directly below the star, for a streetlight, the point directly below the streetlight.) Now pretend you measured an angle of 45 degrees from where you are to the streetlight. If all you know is where the streetlight is and that angle, what it tells you is that you can be anywhere on a circle of a calculated radius out from the streetlight. The one angle won't tell you where you are, but you can draw a circle around the light and you are somewhere on that circle. If you do the same thing again for a second streetlight you will have two circles which intersect. If you add a third streetlight and measure the angle to it, compute the radius you have three circles which intersect in a small area - that's where you are! That's what's going on with our star sights - we use three stars, measure the angles, calculate their position and expected heights and then figure out where we are.
So back to the mark on the chart we made. We moved toward or away from our assumed position by the amount corresponding to the difference in the computed and measured angle. That gave us a point on the chart. Now draw a perpendicular line, a line at a right angle to that point and azimuth and draw a new line. We are somewhere along this line, the line is a line of position. To be exact, we should draw a small portion of a circle with the stars geographic position at its center - but that circle is so large for us that on the chart in front of us the little portion of the circle looks like a line. So just draw a line.
So we have a line on the chart and we're somewhere along that line. This is exactly the same as the coastal situation where we took a bearing to a lighthouse, drew that line on the chart and knew we were somewhere along that line. If you do the same thing two more times with two more stars you get two more lines of position which will intersect in a small triangle, and that will be our fix. We used the stars to figure out where we were on earth. Cool!
You can also use the sun, moon or four of the planets for the fixes.
Celestial navigation is simply to use these bodies to calculate lines of position on a chart. If you draw three lines of position you have a fix and know where you are. In hindsight this all seems pretty obvious. Everybody knows that's how it works, right?
Something you might not know: there are only 57 stars used for navigation out of all the billions and billions of stars out there. Something you do know: stars are really pretty to look at. Something you might not know: the names and positions of the 57 navigation stars.
I don't yet know where the 57 stars are. But now I can figure out where any of them will be at some point in time, walk outside, look in that direction and height above the horizon and there it will be. And that's pretty neat!
I'll be keeping my GPS.
I understood that overview but never really understood what was really going on. Now I know!
A general overview of celestial navigation is really pretty easy. Don't be confused by my description - its probably much easier than it sounds!
All sailors should know how to do simple navigation. One of the easy things to do when sailing around coastlines is to get a fix for where you are by taking three bearings to landmarks. For example, if you know roughly where you are, look at a chart to pick three things you will be able to see. A lighthouse, a radio tower and the end of a point of land. Go onto deck with a hand bearing compass and record the bearings to each of these three marks. Then go back to your chart and draw lines from the marks along the bearings you measured and the three lines will cross in some small area - that's where you are.
Celestial navigation is basically the same thing. The most basic form is where you pick three stars which will be visible and arranged around the horizon roughly equally. Then you go up on deck with your sextant and take a measurement and record the time. With some basic math (addition and subtraction) and table lookups, you can then end up with three lines of position (LOPs) which will intersect in a small area. The area of intersection is where you are. Its the same as for taking a fix with a compass but with more math.
Its pretty cool.
For a star, the basic idea is that the stars have well known positions in the sky at any particular time. This can all be found by looking it up in tables and doing a little math. After doing this math you end up with the geographic position of the star at that exact time - essentially the point on earth which is directly below the star right then. The next step is to assume that you are at some point, your assumed position. This can be done by estimating where you think you are by dead reckoning. If you're far out its ok, that will be fixed a little bit later. Now comes the magic of the sight reduction tables. Given the geographic position of a star, and your assumed position you can easily calculate a bearing to the star and its exact expected height above your horizon. That part of the calculation is mainly done as table lookups and is a little magic.
So what you do is pick a star (or three) from the tables which you want to measure. Then go onto deck and find the star and then measure the angle between it and the horizon with the sextant. A sextant really only does one thing - it measures angles very precisely. When you measure the angle you also record the time. Then you make an assumption for where you think you are and do the calculation to find where the star was expected to be at that exact time. Once that is done, you have two angles: the height of the star where it was expected to be and the height of the star in reality. The difference between these two angles relates to how far away from your assumed point you are.
Hold your arm up for this next part: if the height of the star was expected to be 45 deg above the horizon (hold your arm out at 45 degrees) but was measured to be 30 degrees (slide your arm down to 30 degrees) then: are you closer or further away from the geographic position of the star? After a bit of thought and repeated arm gestures, the answer comes: you are further away! If the angle measured was greater than the expected angle then you are closer to the star's geographic position than you thought.
So almost done now. You have an assumed position and a bearing to the star at the exact time you measured the star. Draw a line on a chart from where you are to the star. Now adjust your assumed point toward or away from the star by the amount corresponding to the difference in the two angles (the computed angle and the measured angle.) Make a mark on the chart at that point. For example, given your assumed position, the bearing to the star (its azimuth) might be 230 degrees and you are 3.5 miles further away - so put a new mark at that point. You aren't at that point, that would be too easy. So what does that point indicate?
To understand what you just did, think of a streetlight. The geographic position of the streetlight is the point just below the light (for a star its the point directly below the star, for a streetlight, the point directly below the streetlight.) Now pretend you measured an angle of 45 degrees from where you are to the streetlight. If all you know is where the streetlight is and that angle, what it tells you is that you can be anywhere on a circle of a calculated radius out from the streetlight. The one angle won't tell you where you are, but you can draw a circle around the light and you are somewhere on that circle. If you do the same thing again for a second streetlight you will have two circles which intersect. If you add a third streetlight and measure the angle to it, compute the radius you have three circles which intersect in a small area - that's where you are! That's what's going on with our star sights - we use three stars, measure the angles, calculate their position and expected heights and then figure out where we are.
So back to the mark on the chart we made. We moved toward or away from our assumed position by the amount corresponding to the difference in the computed and measured angle. That gave us a point on the chart. Now draw a perpendicular line, a line at a right angle to that point and azimuth and draw a new line. We are somewhere along this line, the line is a line of position. To be exact, we should draw a small portion of a circle with the stars geographic position at its center - but that circle is so large for us that on the chart in front of us the little portion of the circle looks like a line. So just draw a line.
So we have a line on the chart and we're somewhere along that line. This is exactly the same as the coastal situation where we took a bearing to a lighthouse, drew that line on the chart and knew we were somewhere along that line. If you do the same thing two more times with two more stars you get two more lines of position which will intersect in a small triangle, and that will be our fix. We used the stars to figure out where we were on earth. Cool!
You can also use the sun, moon or four of the planets for the fixes.
Celestial navigation is simply to use these bodies to calculate lines of position on a chart. If you draw three lines of position you have a fix and know where you are. In hindsight this all seems pretty obvious. Everybody knows that's how it works, right?
Something you might not know: there are only 57 stars used for navigation out of all the billions and billions of stars out there. Something you do know: stars are really pretty to look at. Something you might not know: the names and positions of the 57 navigation stars.
I don't yet know where the 57 stars are. But now I can figure out where any of them will be at some point in time, walk outside, look in that direction and height above the horizon and there it will be. And that's pretty neat!
I'll be keeping my GPS.
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