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Crew finds new career path: "Rudders R Us"
Log Date: July 16, 1998
Author: Terry Moore
Location: Sisimiut
Weather: Sunny, blue sky - yippee!
Click on the pictures below to view enlargements
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You know, as simplistic as my empirical interpretations may be, I genuinely thought I was on to something in the Greenland weather department. Without exception, if the weather is so bad that no right-minded person would venture far past their front door, the wind blows from the south.
If the sky is so blue and cloudless that you are afraid to look up for fear of being overcome with the joy of being alive, and you know that Greenland is the only place you ever want to be, well, then, the wind blows from the north. That's it. The sum of all my meteorological experience here. It seems to hold true irrespective of barometric pressure, frontal systems, or whether or not Homer has changed his socks that day. And here I am on a boat that doesn't go upwind too well, headed north - which all adds up to this one unpleasant truth: we only get to sail on really nasty days.
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Until today, that is. The wind gods chose today to take me to task for my hubris. Not a cloud in the sky, light north breeze all night, and we even started off rowing in the flat midmorning calm in order to show those same gods that we were willing to work for it, so they would take pity on us and waft a little wind our way. Sure enough, after about an hour the breeze started filling in from the south. All of a sudden, Sisimiut seemed a lot closer. Twenty hours of rowing vanished before the prospect of a four-hour downhill slide into the (hopefully) northern terminus of our Greenland voyage.
Which overjoyed everyone on board, except for me. My universe had just gone topsy-turvy. Wind from the south on a sunny day? Four knots on a gentle breeze, and me in my cotton t-shirt? Above the Arctic Circle? I am so lost. And if that weren't bad enough, as soon as we picked up speed under sail, the rudder that we had just put on worked well.
I suppose I should back up a little. The past three weeks have been a continuous educational evolution on Viking rudder theory, all within the confines of this fishbowl. Rob and Hodding and I have dissected, measured, theorized, speculated and just plain old made-stuff-up to try and explain all the problems we have been having coming up with a rudder that works well.
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Let me introduce the cast of characters: we have Rob's rudder (known as "Obs
Uddah" because the letter R reminds Rob too much of risotto, a meal Jan cooked
last year in the roughest conditions, with predictable results) which steers the
boat well, but wants to go hard over to port all by itself, sometimes taking you
with it, depending on wind and sea conditions.
Cleopatra is the big foil rudder (Cleopatra's barge had a foil rudder) which steers
the boat very well, even though Doug accidentally took the power planer to one side
of it in the shipyard in Nuuk. That, however is a different story entirely. Despite
its efficiency, I am afraid of this rudder because of its size.
The Original, sometimes called the small rudder, is the one that we gave up on very
early on in Maine last year. This year, with the attachment point for the rudder
eight inches further aft, this rudder steers the boat acceptably - but it too tries
to go hard over to port if left to its own devices.
And last, John's rudder (John Gardner made it). So here's the problem. Three of the
four rudders are traditional Viking rudders. Two of those three go hard over to port
when you don't want them to. The one that works well - Cleopatra - is sort of cheating
(Vikings apparently didn't use the foil shape) and besides, it is too big anyway.
Ob's Uddah and John's rudder are also a little too big for comfort - they place too
much stress on the attachments. Until we were anchored in Soapstone Harbor near Atangmik,
John's rudder didn't even have a hole in it for the attaching rope, which we call
a withe.
All this experimentation and thought has led me to believe pretty firmly that this
tendency for the Viking rudders to clunk hard over to port is due to the tendency
of the boat to turn to port on its own, together with the fact that Viking rudders
have as much surface area forward of the axis of rotation of the rudder blade as
aft of the axis. (Picture a square with the rudder post dividing it exactly in half.)
Cleopatra has only one-third as much surface area forward of the axis as aft, and
it does not turn by itself. Simple then - alter John's rudder to change the ratio
of fore and aft surface areas, right?
Just as it was literally about to go under the ax, John gave a silent plea with his
big blue eyes for just one chance for his untried masterpiece - how could I turn
that down? I marked out my proposed changes - so that once we put it in the water
and it turned itself hard over, we could drag it back out and begin the alterations.
We sailed for 20 hours in 15 to 20 knots of wind, at speeds of up to 10 knots, along
the most rugged, remote, snow-capped coast I have ever seen. John's rudder required
little more than light finger pressure to hold a course. Effortless. Stunning, actually.
I have been able to justify the rudder's behavior in light of my certainty about
fore-and-aft proportions only because when I drilled the hole for the withe, I moved
it forward, thereby moving the axis of rotation forward, changing those proportions
in what I thought would be our favor. (Much like I can mumble to myself about high-pressure
systems and local weather-makers producing strange winds.)
Whatever the reason, we now have a rudder that works beautifully. But it is still
too big. Now Rob's rudder is the sacrificial goat, and the plan is to make it like
John's, only more along the size of the original. We put it on today for our row/sail
to Sisimiut just to see if any of the relatively minor changes that Rob has introduced
(a shave here, a scrape there) made any difference - knowing that he hadn't done
anything much to its shape.
That brings us up to today, when scooting along on that south wind that shouldn't
be, Rob's rudder - that shouldn't steer - held a true course, whether anybody bothered
to hang on or not. Now we have two Viking rudders that work, and I am finally ready
to throw in the towel and admit that I don't get it. I think Greenland is a magical
place - literally.
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As a postscript, the gods tossed me a bone toward the end of the day. The wind
died a few miles short of town, and we had to row in the leftover slop for hours.
Pretty amusing to watch us ejecting our oar blades out the back of a wave and pitching
face forward onto the deck, everyone stroking at their own pace trying to catch the
elusive crests as they slid past the hull.
With any luck, you won't hear me expounding at length about rudders anymore, although
I suspect the subject will never be very far from the surface until I am sleeping
soundly in a sod longhouse in L'Anse aux Meadows.
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