Sunday, March 27, 2016

Why a Compass?


According to Ritchie Navigation, the advantages of using a compass are:

1 Real time compass headings whether your boat is dead in the water, on a plane or moving slowly against an outgoing tide, the compass gives the boat heading. 

2 Straight line steering helps the helmsman avoid steering a serpentine path when steering by the compass heading.

3 Reliability in all situations is a given and it works without power.


I'd add, Able to continue when locked in fog. I can think of two situations I’ve been in when the fog became so bad that visibility was reduced to just feet… The compass enabled me to continue to the destination.


But what if you don’t have a compass?
Point the boat to where you want to go, them immediately look over the stern of the boat and select an object (e.g., tree) centered over the transom. As you row, keep that object centered. Periodically check your heading, since wind and/or current can move you sideways, and you can miss your target, even though you have been faithful in keeping that tree over the center of the transom. 


To maintain a straight line, in calm conditions, use the wake of the boat as a guide for maintaining a course. Note that wind/current can still blow you off course, in spite of maintaining a straight course.

I use the Ritchie ‘reverse reading compass’, available at
Duckworks.


Ritchie Reverse Reading Compass

When mounting the compass, make sure there are no nearby metal objects. or wires with current, which can affect the accuracy of the compass. The Reverse Reading Compass pictured here has compensation adjustments which enable you to correct for minor compensation errors. See Ritchie instructions for compensation adjustments.

Reverse Reading Compass Mounted in my Lillistone Flint

The lubber line (the red line on the compass which must be aligned with the bow of the boat) shows the heading of the boat. In the first photo, the boat’s heading is 350 degrees, read from the floating card in the center of the compass. The movable bezel around the base of the compass is a way to remember what course you want to maintain.


To use the compass, point the boat to where you want to go, or, using a chart, identify the magnetic course, then either move the bezel so that the desired course is directly under the lubber line. Or just remember the course.

As you row, you’ll notice that you may have ‘wandered’ off your intended course due to wind, current, uneven pulling on the two oars, or just plain being mesmerized by the joy of rowing. To correct the course, turn the boat so that you move the red lubber line toward the desired course.

I like having the compass: I maintain a straighter course when using it… and it’s comforting to know I can still row to my desired destination in spite of low, even zero, visibility.

In the next blog, we’ll show you 7 examples of foot stretchers.




8 comments:

  1. I have the same compass from Duckworks, it works well as you say.
    Do you ever try rowing without looking? Sometimes, especially when tired, I close my eyes for a couple of minutes and try to hold course by the feel of the wind and direction of surf or other sounds. Mostly I can stay pretty close, but there have been a few surprises...

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  2. Yes I do! You're absolutely right about fog, Tom. I wasn't care much about a compass on a small boat until I got into fog on the Wisla lagoon. It belongs partially to Poland, and partially to Russia. I just stopped rowing , to wait for clear view and avoid crossing the border if turning east. My one day trip might take much longer if I crossed it! Few photos of below linked flickr report show that:
    https://www.flickr.com/photos/10196268@N05/albums/72157601960742992

    The boat was Robote by Jim Michalak.

    Wojtek

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  3. A compass is also useful when, because of counter currents or wind, your speed drops below ~1.5mph, and you are using a GPS to follow a route. What happens is that the little blue arrow just spins and points randomly (the GPS will not "point" at low speeds); hence, you may not know which direction you are going. During my Everglades Challenge race this happened on several occasions, and I had to use my mounted compass as well (as the stars) to keep me on a straight line. Rule 1: never leave home in a boat without a compass. Rule 2: Never rely totally on your GPS, no matter how lovely and seductive these devices are. Oh, and Rule 3: Always have an old fashioned map with you. Or several.

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  4. Rick, that's a great idea to row (periodically) with eyes closed to train ourselves to be aware of wind, warmth of the sun, sounds as directional 'hints'...

    Wojtek, your 'almost' crossing over into Russian territory is frightening...glad it turned out okay.

    Steve, I use my iPhone (in waterproof case) with an app called "Cyclemeter" when rowing. It is a quite extraordinary app, providing GPS-like capabilities, such as real-time speed, average speed, direction, calories burned, distance, elapsed time... full map of your route taken... for virtually any sport (cycling, walking, rowing, driving, etc. etc.) Downside is that because "Location Services" (GPS) is turned on, battery life is 2-3 hours only, but that can be extended by turning off the screen and letting it run in the background... I've seen no evidence of the less than 1.5 mph problem you have with your GPS. No 'way-points' capability is another 'downside'... so it's not a 'planning' tool, but rather a way of recording what you've done.

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  5. This is my "nav station":
    https://www.flickr.com/photos/ricks_boats/25510536724/in/dateposted-public/
    Same rowing compass.
    "Charts" - Waterproof kayak maps and a waterproof fishing map of the Delta are good enough for a shallow draft rowboat to navigate most of my local waters. I don't need to know the main channel depth.
    The old Garmin 76 has Bluecharts, but the main thing I use it for is as a speedometer - really useful for navigating currents.

    I worry about winding up in some areas of Oakland, but Russia? Your rowing waters are riskier than mine, Wojtek!

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  6. I like the idea of your 'portable' "nav station"... I assume you can undo the 'thumb screws' and put the nav station platform in a locker, with clips to hold the maps, attached to the platform. Nice job, Rick!

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  7. Wojtek, would you please send me (tomoarcruising@gmail.com) your personal email address... I want to send some materials to you... thanks... Tom

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  8. This is a great blog! Thank you for writing it. I use a compass mounted to the adjustable foot stretcher in my boat. That way I can move the whole thing forward and still read it if I'm sailing. If you are close enough to shore or other stationary objects you can also line up two objects with each other over the transom to get a better idea of your real course and see if you are drifting sideways. You can also hold a compass course and line up a single object with the center of the transom to do the same thing.
    All the best,
    Scott

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