Boats designed for rudders, or not
I agree that most traditional sea kayaks are designed to be relatively balanced without a skeg or rudder. These are not the boats I aspire to paddle, but obvioulsy they are for many sea kayakers. The good news is that most rudders and skegs may be removed from the water when poking around rock gardens or more maneuverability is needed at slow speeds.
My experience is with kayaks that ARE designed for use with a rudder or skeg. My comments are based on this experience where a rudder is not an afterthought, but rather and integral part of a hulls design.
When I was a newbie, the opinions of many here shamed me into unbolting my rudder and storing it in the garage. Without a rudder, my kayak was a weathercocking machine. Somehow I managed to keep this boat going straight fairly well. Despite being out of lateral balance this boat was still faster than the tarditional looking sea kayaks I often passd.
A few wasted years later, I put the rudder back on the boat. My average speed doubled and my range tripled. I had more fun, more stabilty and could now link up surfing runs. However, when I needed to turn into the wind quickly or even when I was just bobbing around, I would flip up the rudder, just like I assume most do with their skegs.
I understand the hydrodynamics of hulls and rudders to a fairly high degree. I have extensive seat-of-the-pants experience in the QCC700 with the three differnt cockpit locations they have offered over the years. I’ve tried these various set ups with and without rudders. I have even swapped out rudder blades to judge the effect of different blades. I suspect I am in a very small minority of paddlers who has analysed rudder use to such a degree and then made the changes necessary to get better performance. Probably more importantly, I have a lifetime at the helm of racing sailboats. I continue to learn about the characteristics of rudder shapes on my surfski. I already have three different rudders for this boat that I’ve only paddled for a few months now.
Really efficient performance begins to happen when a kayak is designed with the CG forward of the LCB (bow down trim) and the lateral forces balance (weathercockings) are balanced by a foil shaped rudder. If the rudder area is tuned just right, you can make the kayak almost lift to windward. At my typical cruising speeds this meant I had to cut about 3/4" of meat off the bottom of the Feathercraft rudder that came on my origuinal QCC700. Once tuned properly, like a well designed sailboat, I cruised in a sidebreeze with a degree or two of positive rudder angle. This meant the rudder was balancing weathercocking forces by generating lift to windward. Once I had this dialed in, this boat resisted sideslipping incredibly well, tracked like on rails, yet was also very responsive to rudder inputs. This is very cool stuff that racing sailboats experience all the time, but rarely experienced or even considered on kayaks.
I wish the seat of my surfski was located about 6" forward. It would be a better boat if the bow grabbed a little more water so there would be just a touch of weather helm when I used an 8" weedless rudder that this boat loves. I am seeing surfski designers begin to ooch their seats more forward.
I don’t remember what the point of this discussion is. Before the haters jump on me more than they already have I need to say this:
IMPROVED SPEED, EFFICIENCY, RANGE, SURFABILITY THAT A RUDDER CAN OFFER ARE NOT NECESSARILY GOALS THAT EVERY PADDLER THINKS JUSTIFIES THE USE OF SUCH APPENDAGES. IT IS THE RESPONSIBILITY OF EACH PADDLER TO DECIDE WHICH EQUIPMENT IS BEST SUITED FOR THEIR PADDLING GOALS.
I use a Kestrel, not sure the model,
maybe 3500 or 2500. It’s readings seems to be consistent with buoy reports and other sites. Not cheap, but a nice gadget.
Dogmaticus
the Beaufort scale
I did some Googling
and found many of my old friends. Assuming you want a hand held unit your choices for a reasonably accurate reading are a propeller of some kind connected to a recorder/display or a hot wire anemometer. The problem with hand held propeller units is that they have to be turned to the wind accurately. I could not find one that also had a vane to control for wind direction. I did find a hot wire model for $160. That is remarkably cheap but I have no idea how well it works. You would normally expect to pay $400 or more. A more difficult problem in measurement from a kayak is that near the surface of the water wind speed varies a lot with distance from the surface. I don’t know if there is a general principle about that. But I do know you can raise and lower the anemometer and get different readings.
Aiming the Unit
Some good points there, Doc. I think that out on the water, aiming the unit would not be difficult, since you can just align it with the Langmuir Spirals (those long streaks of foam). There can be changes in wind direction, but out on the open water they are usually slight when the wind is strong, so the foam streaks (or just aim perpendicular to the waves) seems like it would work. In calmer conditions, I don't think I'd be interested in wind speed anyway, but that's just me. I must admit I'm tempted to get one of these toys someday.
40-45 kts.
I gotta say one more thing about this. Whether by design or circustances when we get into these kind of situations, and we all have, we run the risk of someone else having to come to our rescue and maybe putting their life at risk. No judgement is being past, just an observation. I went out an inlet one winter day at a time my skill level was such that i had no business doing it. The wind and tide changed and i had a close call before i got back safely. I never thought about the fact someone else could have been put in danger trying to save me. I do now. VF
“But he was living his life to the …
fullest.”
Dogmaticus
yes and maybe no
Anything to reduce the effect of the wind helps. Interesting that the Explorer is implicated, as not too long ago there was very little out there that had less windage than an Explorer; most sea kayaks available had far more freeboard. Now, there are lots to choose from.
The whole lower windage thing can make other things worse- edging, for instance. Boats with very little freeboard lose some edging security when water is onto the deck- not so much different as the reason there are creek boats vs play boats in whitewater. Big breaking seas can be unnerving in a boat where a lot can flow over your deck.
As for fully loaded, that is a real interesting point. More mass means it is slower to respond to the wind (kinda nice that the loaded boat is also lower as well, decreasing windage and increasing draft, the latter of which will reduce the effect of lee drift when lying to the wind). Also means it is harder to accelerate, or even build a higher speed to be able to move the CLR forward (by now, should be apparent that that speed is a critical component of turning upwind), and even slower to respond to turning strokes.
At the same time, the most annoying thing that happens when turning upwind is the bow rising up on a crest and getting blown back downwind. The extra mass reduces that effect. I have had only minimal experience, but the theory implies that loading a boat with heavy items at the ends (while still maintaining proper trim) should make the boat less susceptable. I have tried this, and it seemed small, but observable.
Guess it is the old, “not better or worse, just different”.
karl
Thanks…
…I was kind of thinking this through more after I asked and was thinking that, well, it would be better here, but maybe not if the boat was designed like this, etc. Ended up realizing that from what I could figure anyway, it just depended on the situation. Thanks and I appreciate your comments.
Vaughn
As one of the guys who used to go and get people I can tell you that they train for that, and in fact hope you screw up so they can have fun and do what they train for! I recall as a young EMT doing ER shifts and hoping for a busy night....but that meant folk would be badly hurt. kind of a catch 22. Same with Mt Rescue.
Don't sweat it...what is life threatening for a sea kayaker is fun and games for a rescue swimmer. Besides, they need the experience.
Envyabull!
You are a smart guy, and I appreciate your posts, as like Karl’s they are thoughtful and right on. You are in the wrong place here in a sense. These are sea touring folk who love traditional sea kayaking and all that goes with it. I’d say it’s a site heavily influenced by traditional Brit sea kayaking mantra. That’s all good, but it aint where you are.
I’m generalizing I know, but I believe most here don’t do the type of paddling you do, and are not likely to undersatnd your points.
Find a race site, or ocean performance paddling site and i think you wont experience the disconnect. It’s all good, but I think it’s just a case of a poor fit.
Anyone who engages in a rudders Vs skeg BS debate just does not understand the scope of kayak design, or the possibilities, attributes of each. How many skegas are in tha Molokai? I think that’s typically rough water?
good point
I fully appreciate that point and have thought the same thing in the past watching the rescue shows on TV.
I have to say though that if you read one of my responses above you will see that despite the high winds there were enough factors that mitigated the risk to a reasonable level. Again, I would not have done this on the ocean for sure.
Matt
GPs, freeboard, and windage
Has not been mentioned, which may mean its unimportant, but I wonder if factors in dealing with wind to keep in mind are excess freeboard and low windage design overall. I find the AA to be relatively unaffected by the wind, at least the winds I paddle in, and the Force 4 is to a lesser extent although it is a very easy boat to drive into the wind which is a big advantage. Both would seem to be low windage by design. Of course the Greenland hunting SOF is better than either excepting its weather cocking trait. I also find GPs to be easier to use in windy conditions. I admire you folks who can use a EP in the wind. I find that without great care they tend to sail away and can generate a good deal of force to throw you over unless kept low. I wonder if the ability to maintain a high cadence with a GP might be of value in wind since it means less time when the boat is not being influenced by a stroke which in turn might mean less opportunity for the wind to “take” the boat between strokes.
Sorry
But I had a problem with this post right from the start with the title, “weathercocking in a gale.”
You can debate the fine points until your blue in the face, but realistically, what problems aren’t you going to be faced with in winds to this extreme?" Weathercocking would be about the most minor associated problems with the conditions described. Seems pretty simple to me.
To be fair
Matt did use quotation marks around weathercocking in the body of his first post and indicated that he was not referring to weathercocking in the normal sense, but what I would call the "pinning" of a boat by the wind when it gets blown into a beam wind position and becomes very difficult if not impossible to change from that orientation. If anything this thread has been a great discussion of why this happens and how to address it. I think he was also mentioning another, but related issue which has not been discussed which I took to be he was experiencing the boat yawing going downwind on short/steep wind waves.
I agree the winds as described are up there in the extreme range and close to KYAG. After all, at sea 40Kts will generate 30+ foot waves given time. Far above my experience now and in the future I hope.
Wind speed
1) I live near where Matt was paddling. We lost many trees that day, and whilst we were out walking the dogs in the wood. there were some fairly sustained gusts that really scared us that a tree may fall onto us. I spent my youth windsurfing and developed a fairly good sense of wind speed. 40-50 knts is not an unreasonable estimate that day, particularly the gusts.
2) I would like to hear some comments about wind speed relative to height off the water. Certainly, the closer to the ground/water you are, the slower the wind speed, just like the flow at the edge of a river. My hypothesis is that on average, a kayak would experience lower wind speed than that recorded by a buoy or on the deck of a large vessel. Any thoughts?
3) I thought I could just forget about Fluid Dynamics when I transferred out of Engineering School. Argh!!!
That’s certainly true
Wind speed at “kayak level” will be less than the wind speed at whatever standard height above the ground (or water) it is measured. Still, if you are out paddling in a 30 mph wind, as defined by official measurements, and you note what that wind does to your boat, does it really matter that the wind hitting your boat was (30 - x) mph, or is it enough to know how your boat will be affected the next time you are out when the Weather Service says the wind is blowing 30 mph? I’m not discounting your observation at all though. It would be interesting to compare wind-speed readings at different heights above the water. That needs to be done by someone with a boat that needs no paddler’s input to stay upright in those conditions. Anybody want to loan me their anemometer?
Being a…
… Navy trained weather observer/forcaster with sea time at more latitudes than not - and doing a lot of amphib ops in coastal waters - don’t hurt either.
Of course I’ve forgotten a good bit of the details since - but I think the eyes are still calibrated reasonably OK for wind, sea and surf - even though I do spend most of my time in rather languid tropical waters.
long thread, gems everywhere
Windage has been mentioned, and partially discussed. It is just that this subject, like so many juicy ones, has gone on so long it needs a summary page with indexing!
Less freeboard, thus windage, will make a big difference. But like so many things in boat design, it can be tempting to single out one feature and attribute too much performance to that feature (hard chines, anyone?).
Underhull profile that determines CLR also contributes. The Anas has more rocker at the stern than an Explorer or Romany, or Chatham…and the Pintail or Elaho DS far more stern rocker than the AA.
Then there is the issue of distibution of windage. Notice that most sea kayaks have more windage ahead of the cockpit, not only in height, but also the common raked bow. If one understands the effect of the winds abeam while making way, and why the CLR moves forward with speed, thus producing weatherhelm, then it stands to reason that the extra windage forward, which would produce a lee helm, will then help to “balance” a boat’s tendency to weatherhelm. Whew, sorry for that run-on sentence!
Problem being, the extra windage forward is what can contribute to what one person coined as “pinning” the boat, once over a given wind speed. Most attempts to design in such features will balance a boat only within a certain range of wind speed.
Two local paddlers, both petite (but one REALLY strong), started with a Romany years ago; they found it hard to turn upwind. One got an Anas, the other a Vela. Both were very pleased with the greater ease in turning upwind in higher wind, although missing the Romany for tracking in more typical Force3-5. But now,one just got an LV Romany, and was so happy in Force 5/6 that she immediately sold the AA! Her friend tried the LV, and now has a very nice Vela for sale…
Moral? Re-read the paragraph starting “less freeboars, thus windage…”
As for the GP issue, that is a can of worms! I have an inherent distaste for making such distinctions- for every positive attribute of an GP in high wind, I can come up with an equal number of negatives; same for the standard paddle. The common denominator is the paddler, and their ability to use the positive features and adapt and accomodate the weaknesses of their chosen tool. The group that regularly paddles the Gorge in high winds for the last decade will often switch tools- two people prefer GP’s, the rest standard paddles.
Oh, the petite but not so strong paddler in the Vela that is for sale? She tops out at Force 6, and is not happy but not scared, and is very comfortable and in command in Force 5 (she is 5’2" and 95lb!). One would think that a GP would be a great tool for her (or so I tried to convince her), but her favorite tool is a wing paddle!
Love that phrase, “different strokes…”
So diplomatic!
So well said, Salty.
If my responses to Envyabull seem harsh, it certainly comes with experience within his realm. I am no enemy of rudders! If there is anything that really bothers me, it is that Envy’s excellent summation at the end of the previous post (nicely put variation on “different strokes”) is advice that isn’t apparent in some of his posts.
The viewpoint I have taken in this subject is that of skill based approach, rather than technology. The the “British” approach alluded to by Salty is appropriate- the original poster was inquiring less about what tool should he be using vs what was the environmnental effect that he couldn’t understand. In the BCU 4* sea assessment, if a candidate’s boat has a rudder, it must be fixed inoperable. I am very much in favor of that ethos- if a sea kayaker cannot control a boat without a rudder, do they really understand the forces on the boat, and be able to control the boat using skill instead of technology? Rudders -and skegs!- can break, and if on an expedition, or off shore in rough seas, a kayaker cannot control their boat, I am not sure I want them in my group.
Yeah, Salty, spot on. And in a way, so is Envy. The goal of this is to identify the needs of a group of sea boaters, try to understand what Mother Nature throws at us, and not fight. She will win.