Piloting 101

[tartansailor]

My respects to the accomplished Skippers of the board, but this is really basic and intended for our newest friends to sailing that I have not yet met.

Compass 290°
Variation 8° E
Deviation 13° W
Boat Speed 10 knots
Current set 005°
Drift 2 knots

What will be the intended track?
What will be the speed of advance?

Don't bother replying, just do it, and I will post the answers this Friday. If you need help, then by all means please send me a private b-mail with your answers, and I will respond in confidence.

Dick

[Neil Gordon]

Good one! (I like how you left out the GPS.)

[ronkberg]

Hi, I hope you are going to give me some navigation lesson(s) on Friday, rather than just the answer. I always found the answers in the back of the book in high school, but navigation on the ocean is much more important to a lot of us reading this board.

I am also curious to hear from others about where to get some navigation courses. I assume that the Maine colleges would have such courses but are there other places, ie tech schools? This could be another way to fill the winter months.

Thanks, Ron

[Joe CD MS 300]

Ron,

The coast guard auxiliary has a good coastal piloting course, at least they did 15-20 years ago, and it was cheap.

Joe

[winthrop fisher]

coast guard still does and free on some of them....

[Joe Mac Phee]

United States Power Squadrons offers a whole series of courses including Piloting and Advanced Piloting (and Marine Electronics, Engine Maintenance, Sail, Weather, Celestial Navigation and more).

Go to the USPS web site to find the Squadron near you and ask about membership. USPS offers a basic boating course to the general public and offers the much more advanced courses to its members.

Joe Mac PHee

[chase]

Ron,

I highly recommend the Power Squadron course in Piloting. Having only sailed for a couple of years last spring, it gave me the confidence to "get out there". The list of mistakes I've avoided due to a solid foundation in Piloting is substantial. The list of mistakes I've MADE is also substantial, but nothing too serious. I like that I learned how to use bearings, dead reckoning, and other techniques in lieu of just GPS.

When I did not receive my test results in a timely manner, I contacted USPS and received a response that night. The next day I heard from their national education director. I will tell you this -- USPS takes education seriously.

I cannot say enough about how much I advanced as a sailor during that course. I'm looking forward to more.

Chase

[Sailing Soldier]

Try Starpath. I think their website is just "starpath.com". I took their Coastal Navigation homestudy course while I was in Iraq. It was pretty good.

[tartansailor]

Neil,
Have a hand held on the boat but only keep it in case of a MOB, or my chart blows over-board. I think that it is taking a big chance sailing out of sight of land and relying on GPS alone to get by. A lightning strike close to the boat, a failed moisture seal, dead batteries, dyslexia in entering coordinates, accidental delete and the list goes on. And when the fog hits its panic city. The best practice I have found are Predicted Log Contests to help answer the question"Where Are We?"
Competing in around the buoys races also taught me to read wind shifts by compass headings.
One time my mentor blind folded me and ordered me to sail a couple of dog legs to a specific destination. The learning curve never peaks.
Dick

[Neil Gordon]

I think that it is taking a big chance sailing out of sight of land and relying on GPS alone to get by.

It's the "relying on ___ alone" part that gets you. One bad input and you're done. Several independent methods and/or independent confirmation is the best practice. None of this requires electronics.

And it has nothing to do with being out of sight of land. It's close to the land where most people get in trouble.

[Cathy Monaghan]

Ron,

Ditto to what everyone else has said about the Coast Guard Auxilliary and the Power Squadron classes. They're are good and FREE. If they are not having any classes in your area, most sailing schools have coastal piloting/navigation programs.

• CLICK HERE for a list of Coast Guard Auxiliiary boating classes. If you already know which course interests you, use their Class Finder to locate a course near you.
  
  CLICK HERE for information on the Power Squadron's boating course. And use this link to find a course near you.

If you can't find a USCGA or USPS course near you, try one of the following schools (they're classes are not free):

• Sawyer's Sailing School, Auburn, ME. Ph: (866) 783-6882. Fax: (207) 783-6882.
  
  Castine Kayak Adventures, Castine, ME. Ph: 207-866-3506 (winter) or 207-326-9045 (summer). (Hey, coastal piloting is coastal piloring whether you're in a sailboat, powerboat or kayak!)
  
  The Maine Sailing School, Falmouth, ME. Ph: 207-878-5213.
  
  Old Quarry Ocean Adventures, Inc.,Stonington, ME. Ph: 207-367-8977. (More kayakers)
  
  WoodenBoat School, , Brooklin, ME. Ph: (207) 359–4651

[tartansailor]

Piloting 101

You are at the helm of a fast sloop on a broad reach surfing in a hard blow, and wondering where you are heading.
Glancing down you note the following:
Compass 290°
Variation 8° E
Deviation 13° W
Boat Speed 10 knots
Your Pilot Chart for the month records: Current set 005°, Drift 2 knots.

What will be the intended track?
What will be the speed of advance?

The first step in determining your True Course:
Remember this memory aid:
T V M D C
True Virtue Makes Dull Company. Add whiskey

True Course Variation Magnetic Course Deviation Compass Course Add Westerly
? 8°E ? 13°W 290°

When calculating the above from left to right you add west and subtract east.
When calculating the above from right to left you subtract west and add east.

In order to get to your True course, you must first determine your Magnetic course, so from above you see that you need to go from right to left, so you subtract west. Therefore:
290° minus 13° west = your Magnetic course of 277° Now you have:

True Course Variation Magnetic Course Deviation Compass
? 8°E 277° 13°W 290°

Again when going from right to left you add east, so 277° plus 8°E gives you your True course of 285° Now you have:

True Course Variation Magnetic Course Deviation Compass
285° 8°E 277° 13°W 290°

Your intended track is 285°


Turning your attention to: Determine Speed of Advance.

Take a sheet of plain graph paper and a protractor. In this example a scale of ½ inch per mile works well, so a speed of 10 knots would be represented by a line 5 inches long.

With North at the top of the sheet and West on the left side, select an O (origin), and from there draw a 5 inch line (to represent 10 NM) at an angle of 285° your True course.

Label the top of the line T H 285° for True Heading of 285°, and the bottom of the line S 10 for a speed of 10 knots.

Your drift is 2 knots, so that would be represented by a line 1 inch long at an angle of set of 005°.

At the end of the line on the left draw a 1 inch line at an angle of 005° Label the top of the line: Set 005°, and at the bottom Drift 2.

Draw a line connecting the O origin to the end of the drift.
Again using north at the top of your sheet as a reference, measure the angle of the connecting line. You should get 296°

Measure the length of the connecting line and you should get 5¼ inches. Plugging in your scale of ½ inch per mile gives you a
Speed of advance of 10½ knots, but your track is 295° not your intended True course of 285°.

Label the top of the connecting line your track TR 296° and the bottom your speed of advance SOA 10.5°

This example shows that in 1 hour you are 2 miles off course, which reinforces the desirability of using a Pilot Chart when planning a cruise.

Dick

[Neil Gordon]

This example shows that in 1 hour you are 2 miles off course, which reinforces the desirability of using a Pilot Chart when planning a cruise.

Outstanding!!!

Just to point out Murphy's Law of Set and Drift...

Adverse currents (or leeway) will surely set you onto the rocks if you don't adjust your course accordingly. If you steer for the rocks, otoh, favorable currents cannot be relied upon to keep you safe.

[Nancy Martin]

As a "home schooler" at the moment, learning navigation from my husband, I have a lesson pretty much every night. If not a lesson I have homework or a quiz pretty much like the one posted.

For my last birthday, in November, a friend gave me a shirt with "navigator" on the back. We have an ongoing grading method that is if I miss a point on the "quiz", I lose letters from the shirt....he doesn't actually remove them just tells me what letters I have lost.
Currently I am a "igator" having lost all letters when I went aground on a rocky shore near Anachortes, WA. Now I'm having to earn them back.

Better here on dry land then when we charter in Anachortes this summer.
Nancy

[rtbates]

IF you are sailing a compass coarse with a magnetic compass why care about the difference between mag and true north. Just plot magnetic using the charts mag rose? And visa versa.