Wednesday, February 27, 2013

Know Your Kayak Under the Water (part 1)

As kayakers, we rely on our boats to impose our will on the water, exhorting pure human power against the wind, tides, and currents.  Beyond our own endurance, we have our kayaks and their carefully designed characteristics to safely and efficiently ferry us to our destination.  However, most paddlers when considering a kayak acquisition look above the waterline when over 90% of its vital characteristics lie below the waterline.  Recently, I looked through manufacturer promotional material for several kayaks.  I found happy paddlers in emotionally provocative colorful pictures as one could imagine with a detailed list of above waterline features.  But found little to nothing substantive about the all important hull design.  Sadly, most paddlers do not understand the design features of their hull and its intricacies.  Above all, the hull is the very essence of a kayak's designed performance.  As individuals that kayak, we have different demands as diverse as the seasons.  And selecting a kayak compatible with our skills and needs is very important.  If one design was perfect for everyone, all kayaks would look alike, and we would not have hundreds of models to choose from.  But hull design is all about trade-offs.  Features that deliver the performance a paddler desires or needs will often require a sacrifice in another area.  Despite how instrumental your kayak's hull is to its performance, precious little is has written about it, leaving kayakers in the dark on exactly how and why their hulls perform as they do, and what to look for in a hull shape when considering a kayak purchase.  In this series of articles I will bring to light the deep dark secrets of hull design in simple terms.  We will examine facets of stability.  Explore hull shapes and features below and above the water line that affect stability and in later articles examine hull characteristics of speed and efficiency for moving through the water.  But first we will establish a premise for our examination of hull designs with some basic physical principles to help us dissect hull shape features.

Of primary importance to our endeavors on the water is stability.   In nearly all watercraft, we look to the design of the hull for stability and must sacrifice streamline efficiency to have it.   However, a kayak will permit the task of stability to be delegated to the skills of the paddler, allowing craft stability to be exchanged for a more streamline performance with lower resistance.  But unless your primary task is powering the craft while providing stability every moment you are on the water, this delegated task may not be willingly accepted by many.   Bird watchers, fishermen, and paddlers out for a relaxing day on the water may desire a kayak that provides a high degree of hull stability.  But at what cost?  And why the tradeoff?

First we will look at what stability actually is.  Our kayaks move and twist on the 2D plane of the water rotating around 2 axes.  Since sea kayaks are long and stand little chance of flipping end over end, lateral rotation is of little consequence. So our only concern is its rotation about its longitudinal axis running the length of the kayak.  When we lean left or right we are applying torque on our kayak to spin about this axis.  As we float upon the water, the weight of our kayak and all its contents is pressed upon the water with a downward force and held in check with an upward opposing buoyancy or (weight displacement force).  If the kayaker is properly centered in the kayak, the center of gravity will go straight down through the axis.  In reaction, the opposing center of buoyancy will move straight through the axis in the upward direction to keep the kayak and its contents in check.  Since these forces pass straight through the axis there is no torque being applied, thus no rotation about it.

If the paddler leans to one side, the center of gravity will move away from the axis and impose a torque upon it.  At this point, the designed features of the hull come in to play to react with an opposing righting force by adding more dry hull volume (floatation) in the water on the side of the lean thus imposing an opposing torque by moving its center of buoyancy off-center in the direction of the lean.   Since the weight of the kayak cannot change, to add dry volume on one side of center requires the kayak to reduce wetted volume on the opposite side.   Buoyancy on the side opposite to the lean is also reduced which helps the center of buoyancy migrate in the direction of the lean.  However, when the kayak runs out of dry volume to put in the water, it can no longer move the center of buoyancy to match the center of gravity.  At that point, an unopposed torque will be applied to the kayak hull and it will capsize.   This is the point of capitulation.

So what can we deduce from these physical facts?  First: a kayak hull has only has a fixed amount of stabilization reserves.  If they are spent early providing primary stability, we can expect the kayak hull to capitulate earlier.  Also, as a long wrench with more leverage can apply more torque  than a shorter wrench, a wider kayak will have more leverage to apply more counteracting torque against a leaning torque.  But widening the beam will dramatically sacrifice speed and increase water drag when the kayak moves.  A tradeoff that must be considered wisely.

 So what are these features that work for us?  What does a featureless hull look like?  Lets examine a featureless hull which is simply a floating cylinder.  Since it is round and featureless, its center of buoyancy will always be in the center and cannot move to either side.  Its perfectly round shape does not allow any more volume to be added to one side or taken from another.   It is the same on both sides all the time.  Consequently, any offset in the center of gravity will generate torque on the cylinder, opposed only by the small forces of the cylinder's inertia, and friction of the water.  Picture yourself standing on a perfectly round floating tree trunk.

Since have a stability budget, how do we spend it?   If you fish or birdwatch, and paddling is your secondary purpose, or you just want a stable, secure experience in calm conditions, you may want to spend a good part of your stability budget on primary stability.  Primary stability is the instantaneous ability of the craft to apply a righting force to a leaning motion.  Kayaks with high primary stability feel stable initially as any leaning is met with an instantaneous counterforce.   In order to accomplish this, primary stability must be located in the wetted volume of the hull.  High primary stability hulls will have a flattened bottom with possibly a slight "V" or gentle rounded shape.  As such, the hull size below the waterline is larger and drag from water friction is rather high, affecting performance.  Since much of the stability budget is spent on this primary stability, there is less of a secondary stability reaction.  But high primary stability will require more leverage, thus a larger stability budget which must be bought by widening the beam (width) so the hull can achieve enough righting torque on the axis with a longer lever (remember the wrench).  Typically, high primary stability kayaks are wide and short as they do not need an excessive waterline for a kayak that is not designed for blazing speed or cover a lot of distance.  But they are a lot of fun, very practical in rivers and small lakes, swamps, and estuaries and highly maneuverable.  But, a high primary stability exposes the kayak to a serious side effect.  In our theoretical illustration above, we observed the mechanism of stability as a function of the kayak's flotation and the water surface.  We know the kayak will attempt to bring itself level to the surface of the water.  But the surface of the water is often not level (the slope of a wave).  So a kayak with high initial stability can right itself sideways to a small degree; enough to introduce considerable instability in rough water, requiring mitigation with bracing skills from the paddler.  But, for paddlers who rarely venture into rough waters and have no desire to travel far or fast, a primary stability kayak will be a fine investment for a leisurely enjoyable ride.  Performance paddlers will find themselves fighting a sharply increasing  drag as they ramp up speed.  The increase in speed will hit a wall as the kayak reaches its maximum hull speed (explained in a later article).

A kayak facing rough seas will need to minimize the instability side effect from its primary stability, and reserve its stability budget for secondary stability.  Unlike primary stability, secondary stability will not respond instantaneously but apply stability further into the lean.  Secondary stability also exhibits less of the destabilizing behavior in waves since the hull will not react until much further into the lean.  Unlike primary stability, secondary stability assets are in the dry volume of the hull above the waterline.  In the first illustration above, notice how the "V" concentrates most of the flotation in the center, while the flotation at the extremities is pushed out of the water into the dry area of the hull.  This is the secondary stability area in reserve.  Since the dominate flotation force is in the center, the kayak will pivot about it and feel initially unstable until the secondary stability is deployed.  In the second illustration, when the kayak rotates about its axis, dry volume is deployed into the water bolstering flotation at the edge of the kayak, which in turn moves the center of buoyancy to counteract the leaning force.  Since secondary stability assets are stored above the waterline, these kayaks  enjoy an added advantage of a more streamlined hull with much less wetted hull surface resulting in far less drag from water friction when the secondary stability is not deployed.  Secondary stability kayaks cater to more advanced paddlers seeking performance.  In many models, manufacturers will further narrow the beam (width) considerably stripping much of its righting force leverage.  And by this action, delegate much of task of stability to the bracing skills of the paddler in exchange for a considerable increase in performance.  Manufactures may also choose a more rounded hull without a "V".  But the stability principles are the same with more rounded surfaces offering less primary and more secondary stability, with flatter rounded bottoms offering a higher degree of primary stability.  Novice paddlers will find secondary stability kayaks deceptively unstable and unsettling.  With a much more narrow beam, these kayaks will have a much smaller stability budget, but will store most of this tighter stability in reserve for a time when it is really needed.

To illustrate primary stability and secondary stability I presented two mutually exclusive theoretical kayaks.  But in reality, no kayak will have all of one and none of the other.  All hundred or so kayak models will fall somewhere in between catering to many skill levels and a wide range of venues and conditions.  When a paddler chooses where they want to spend their stability budget, they should deliberate long and hard to find the kayak that best suits their needs in the near term and longer term.  Also consider where you are going to paddle and where you want to paddle.  They must also assess their skills and allow room for improvement.  A kayak designed for calm conditions can also perform well in challenging conditions if used with proper skills.  When I purchase a kayak, I am initially a little unstable and grow into its characteristics as my skills improve.   Paddlers for whom the kayak is a vehicle for another purpose or activity may want a lot of primary stability so they can focus on their secondary activity.   Kayakers wanting performance with the intention of piling up a lot of distance will want a performance kayak with a low drag.  Paddling a considerable distance with a higher drag hull can feel like towing a second boat.  A day on the water with a prospective kayak is better than a short test paddle.  When shopping for a kayak, try a lot boats.  You may just fall in love or learn a little more about who your are on the water.

In the next article of this series, we will apply some of our new found knowledge to examine the stability characteristics of a number of actual hull shapes.

Sources:
http://www.rcwarships.com/rcwarships/nwc/stability.html

Copyright 2012 Lyman A Copps

Friday, December 14, 2012

Big Fun in Small Surf


A few kayakers you may know ventured into some winter surf. I am still without drysuit (hurry, hurry with the replacement, Kokatat!) so I came out with my camera to shoot some photos.

The surf that day was quite mild (1-2 feet) and mushy, but folks still had a great time. What's interesting to me is how much variety, fun, and challenge there is in the small stuff. As you look at these photos, it's good to consider how high a two foot wave can look when it's cresting above you
and you're seated in your kayak. Why, it can block your view! Imagine, then, what seriously big surf must look like--its weight, muscle, force. When I read about the stuff, say, Freya Hoffmeister has paddled, I am deeply humbled by both the ocean and true courage.

Take a look.

 Here's the start to the day. This is often how we view the water, standing. It doesn't look dramatic, just a calm day at the beach.


 When you're launched and just past the breakers, you can see how even small swell appears to swallow the kayak.
 From shore, standing, you might not even notice the swell. Look at the photo. You don't see the swell clearly with the eye. But you can tell it's there once you realize that Chris and Lee are in their kayaks, not swimming.
 When the wave crests, it looks really big! This wave may have crested at just above 2 feet. But look
how it appears from the vantage of Dawn, the kayaker!
 And, even the small stuff is fun to surf, lots of energy and great rides.
 Sit on tops, like Frank's, are a lot of fun in the surf. If you don't like to paddle a decked kayak, and aren't interested in learning to roll, these kayaks are terrific options, and fun in the surf!
 This photo looks dramatic! Lee has just finished surfing and now it's time to brace!
 With a nice low brace, Lee and his kayak bounce through the soup. It's counterintuitive, but leaning in to the foam pile with a solid low brace keeps your kayak upright.
Here, Chris is finished surfing and ready to brace.
 Frank zooms down a nice one!
 I like this photo because it looks so COLD. I think that's a stand up paddle boarder behind Lee. Lots of the SUP crowd is out these days.
 More pretty ones.
 A 1.5-2 foot wave can be truly fun. Look at the ride Dawn's catching!
 Whee!
 This is a pic of Dawn doing a cool layback high brace she learned at Sea Kayak Virginia.
I mean to try these sometime.
So don't think you need massive surf to have a good time in the surf zone.  Most sea kayakers wouldn't know what to do with a wave that's three to four times the size of the one in the photo.

Small surf is fun.

Saturday, December 1, 2012

Finding Stability in a Sea of Chaos


As we indulge the sounds of life, a mosaic of diverse vibrations, notes, and beats play upon our ears at times orchestrated with purpose, other times randomly.   With the experience of life, we perceive these sounds and wire our minds to react to them in thoughtful predictable ways.   The sea is not unlike our terrestrial world.  As we watch the ocean, we see another type of concert manifested in the waves with rhythmic vibrations, harmonics and beats similar to the sounds we surf with our ears.  As kayakers, we are afforded the unique opportunity to become part of the music of the sea.  Where every other water going vessel passively opposes the sea's forces, the kayak alone is able to interpret and play upon each wave with elegance and precision, realizing remarkable stability for watercraft of such narrow proportions.  Last year I faced faced a situation of hostile conditions far out at sea for more than 10 hours (see "50 miles at sea") and learned in course of the trip, rather than futilely react to each wave, there was a opportunity to assimilate with the rhythms of the sea and feel stable in the midst of chaos using my paddle as an instrument, and my cadence as a verse.

But the waves and motions of the sea are even more complex and diverse than a symphony orchestra.  Waves originate from many sources and many directions, close by from boats to storms and winds hundreds and thousands of miles away, and even reflect from rocks and shorelines and move in opposite directions making the water very confused and difficult for kayaks.  A paddler unfamiliar with such conditions, like a person encountering a loud strange and unanticipated sound will react defensively with a thoughtless opposing reaction.  As we gain knowledge of unfamiliar sounds, we respond with a predictable and well thought out action.  Similarly, as kayakers, we will encounter difficult conditions many times and must develop ways to handle these situations.  Especially in a long trip where we may face difficult conditions for hours and days at a time, we do not have the luxury to react to each wave.

Large cruise ships use sophisticated stabilization systems with bracing fins that work exactly in the same manner as a kayaker braces with a paddle to provide remarkable stability in rough seas.  As its complex computer algorithms interpret the sea's motions and rhythms, so do our minds in an even more eloquent way with the the ability to anticipate the conditions and instinctually apply the proper stabilizing actions.

The kayak itself has little innate stability.  Although wider beam kayaks for the novice possess a higher degree of primary stability,  nothing comes close to the skills of a skillful paddler.  In wavy conditions, primary stability works against the paddler and shows its weakness inherent in every other craft as it characteristically applies a righting force to bring the kayak level to the surface of the water.  If that surface is on the slope of a wave, the kayak's primary stability will actually attempt to right the kayak more sideways which can be seriously destabilizing in the moving motion of the waves.  In challenging conditions, lower primary stability is more desirable as the paddler assumes the responsibility for providing the stability.  But every kayak still has some primary stability, and the paddler will be pressed to mitigate the affects of the waves on that primary stability in addition to the other effects by applying a brace to each stroke.

Applying a brace to the stroke is a simple matter slightly angling the blade downward during the stroke.   Angling the blade will add a downward force component in addition to a forward thrust.  Adjusting the downward angle of the paddle can be done very quickly.  Often times the paddler will need to try a number of angle settings to find just the right bracing strength.  But once the right angle is found, its normally good for the wave set and should be noted for similar reoccurring sets of waves.  If more bracing force is required to cross over a sharply pointed wave or through a whitecap break, a downward pry can be added to the stroke by pushing straight down on the braced blade during a stroke.  The pry can be used only when a brace is applied to the stroke.  Otherwise, the blade will knife downward and possibly compromise stability.  If a wave hitting the kayak requires a pry on a brace, the paddler should be ready to brace quickly on the other side to address a possible abnormally harsh transition to the downward slope with a temporary shift to a fast cadence.   As I paddled long hours in rough conditions, I was periodically hit by isolated waves which posed a problem, requiring a fast cadence until the wave passed.  On a couple of occasions  a wave broke over my bow, causing the kayak to spin off course like a compass needle.  The fast cadence possibly averted a capsize far from shore.    

As waves travel through the ocean they combine and cancel each other out.  Over a distance, the resulting set of waves normalize into a consistant procession known as a "wave train".  The waves further congregate into groups like harmonics from a string instrument, which  called "sets".  The kayaker will notice groups of similar size waves passing in cycles as wave sets come and go.  The paddler will need to adjust to changing wave sets by altering the brace angle and cadence to match the oncoming set of waves and make fine adjustments.  Through a number of cycles the paddler will notice a pattern which can be anticipated and formulated into a strategy to be used at any time in the future.  As we learn to anticipate the notes of songs we hear many times, paddlers on longer trips will have the ability to predict when wave sets will arrive and structure tasks around the arrival of specific sets of waves.
As a padder moves through a rough conditions with the wave train at the beam, the kayak will transition between the upward and downward slopes of each wave.   With a normalized wave train, the waves are spaced consistency.   The paddler may use this to an advantage, by matching their stroke cadence to the consistant period of the wave train.  A slower cadence is used for longer wave periods.  A faster cadence is used for more confused conditions with sharp pointed waves.  When in doubt, I always start with a faster cadence and adjust downward to empirically match the conditions.  The transition between braces should match the crest and the trough where the slope changes.  After a while I was able to develop an instinct to match my cadence to the wave train and develop a strategy for a number of conditions and realize a feeling of stability and confidence in a sea of chaos as these motions became more instinctual.

As kayakers, the chorus of the sea summons our skills and intuition to artfully ply confused waters with uncommon grace and dexterity while bearing witness to its every nuance like no other craft.  As a musician contributes to a song, the kayaker flows with the beats and rhythms of the sea, wielding their paddle in a special art of seamanship as a small contributor in the greatest composition.


Copyright 2012 Lyman A Copps

Wednesday, November 21, 2012

Kayak Katamaran Kabana
10/25/2012


I am ever in search of the perfect camping solution for different situations, and a recent post by FastYak on the CKC forum shook loose some ideas I had about a floating camping set up. I'm not thinking of a pontoon boat or a platform with flotation that could be towed by kayak to the location of one's choice. My idea is similar but more compact, which is appropriate for a small boat. 

Mountaineering and the relatively new sport of tree climbing/camping make use of suspended sleeping platforms or portaledges like this.  I have no idea how they transport the things but am assuming they don't climb up the wall or tree with the fully assembled platform hanging off their backs. Presumably it comes apart like a tent and can be stored more compactly. 

The thought of sleeping suspended that high is absolutely terrifying to me.  Being wide awake is no more comforting. I can barely even stand to look at the photos. However, the platform, minus the suspension straps is an idea that could possibly be modified for paddling. 

Such a kayaking platform would consist of two side poles and a spreader bar on each end (or vice versa) between which some kind of taught strong fabric is strung. The whole thing would be securely supported across the back and front decks of two kayaks (the "pontoons"). To get an idea of how the crossbars might work have a look at this photo of two double kayaks attached together like a catamaran for use with a Balogh Sail. For the Kayak Katamaran Kabana there would only be 2 crossbars. There would be some permanent mounting base on the kayak to which the poles would be attached. Pole length would be determined by the desired size, structural requirements and engineering limitations of the materials. The longitudinal bars would of course have to be attached in some way to the crossbars.

It could be a camping platform, sun deck, swimming/diving/fishing platform, etc. A tent could be erected on top. To reduce weight and bulk it might even be possible to use strong specially constructed paddles for 2 of the poles with those also serving as the spare paddles. Other dual purpose features could possibly be incorporated as well. Perhaps a folded configuration of the fabric could double as a sail with poles or pole parts serving as mast, boom or spar. Also, in heavy wave conditions having the two kayaks securely attached to each other could provide additional stability, more like a catamaran. 

If designed right it could be taken down and the fabric stowed in a hatch with the poles stored on deck as are spare paddles. Since 2 kayaks are needed for support there will be 2 kayakers who need a place to lay their heads. So a double platform like this Black Diamond Cliff Cabana would be needed.  For mountaineering these platforms must be over-engineered for strength given the consequences of failure. That also makes them heavy, the Cliff Cabana weighing about 20 pounds. Seems to me a kayak supported platform would not have to be that heavy. 

Has my imagination run wild? Probably yes. But it would be so cool to have a Kayak Katamaran Kabana - paddle over to a unique corner of the marsh or swamp, drop anchor or tie off to a tree, set up the platform and spend the night gently rocked to sleep on the water.

Any mechanical, structural or materials engineers out there with any ideas about how to do this?

Monday, November 19, 2012

Beautiful Contrarians



Sooner or later someone will say to you, “Everything about learning to kayak is so counterintuitive.” For instance, to turn your kayak, you do all the work on the side opposite from the direction you wish to turn; to keep your kayak from turning over in a wave, you lean in to the wave, sometimes until you are buried by it, in order to stay upright; to roll, you keep your head in the water until the end. At first these things feel completely, dangerously unnatural. Why? Because they are unnatural-- at least to our land brains.

Maybe, like me, after you've kayaked a bit, you’ll begin to discover that your land intuition isn’t all it’s cracked up to be, and that by learning to kayak, your brain becomes engaged in the entire world differently, all the time, not just when you're on the water. Perhaps when you are wanting to steer a situation the way you would steer a car, you think: no, this situation requires my kayak brain, and to steer this situation, I must work on the opposite side, even though it is counterintuitive.  Perhaps someone pushes you around and you think it’s time to hide, but you learn to lean in hard against whatever’s coming at you in order to stay upright. 




Or maybe you find yourself suddenly upside down and submerged and wanting to panic, but kayaking has taught you that you’re fine, you can hang out a while without worry or panic, only to roll back up, and keep paddling forward.

Kayaking may be counterintuitive, but the lessons transfer well to the non kayaking side of life too. 

Tuesday, November 13, 2012

A Harbinger for an Ancient Legacy


Recently, the science of kayak hull design has taken and interesting turn which brings together aspects of the kayak and surfski into new exciting high performance craft that promises to shape the future and change the way we paddle.  In this article, I present some background information and dive into design features of the Epic 18x which I believe is the most compelling hybrid design to date.

The kayak is a remarkable invention of the Inuit people allowing them to thrive in barren, hostile lands, not otherwise suitable for habitation.   This powerful tool while bountiful with its benefits, demanded a discipline and strict set of age old skills.  Modern renditions of the kayak gave this remarkable craft to the masses and introduced them to the rich Greenland traditions and discipline.  But nothing from the past is immune to the scrutiny of science, as paddlers demanded greater performance and mastery of the seas.  As science and technology have influenced the kayak, the surfski, having come from a very different past, faced an even more profound transformation, producing remarkable paddle craft capable of achieving high speeds on the rough ocean, not only squeezing efficiency from the paddler's every stroke, but augmenting it with energy captured from the sea itself.  As the quest for kayak speed progressed, high speed flat water racing kayaks emerged, achieving high speeds, but leaving the paddler with a much less seaworthy craft as optimizations for speed sculpted away its traditional rough water handling features.   However, the kayak industry is now taking a long look at the surfski and finding ways to adopt its remarkable design elements.  Recently, one kayak manufacturer introduced an exciting new iteration of its kayak that is every bit a kayak above the waterline, but every bit a surfski below the waterline.  While new designs are common, the paddling community took notice as this new radical design achieved staggering speeds and proved itself a formidable expedition kayak.   However, as with the racing kayak, there are always tradeoffs in exchange for gains.  But, for the first time, a near hybrid design emerged, capable of being paddled like a kayak or surfski on the ocean,  casting a shadow on the pedigree of two rich and storied legacies and their legendary disciplines.

The surf ski sprouted from modern western culture along the coast of 20th century Australia.  As the populations ventured into the turbulent surf,  a need arose for a suitable lifesaving craft capable of negotiating the surf.  In New South Wales, Harry McLaren and his brother Jack in 1916 built sit atop, hand paddle boards to navigate the family's oyster beds.   Variations of these craft were later used for lifesaving and proved much more agile than 5 person surf boats that required a high degree of skill.   In time, lifesavers realized a double surf ski could do most everything a life boat could.  These early surf skis were very wide and bare little resemblance to those in use today. With little reverence for its past, the surf ski was transformed into a high speed, ocean going paddle craft for recreational and racing purposes.  The length grew to increase the waterline for speed and provide more stability when smashing through the waves.  To reduce drag, hulls were narrowed and the "swede" hull design which places the point of maximum beam behind the cockpit was implemented.  With the point of maximum beam behind the cockpit, water inertia and friction on the hull is reduced as water is moved out of the way more slowly over a longer wedge.  The swede hull also places the paddler closer to the water for a better vertical stroke by locating the cockpit in a more narrow part of the hull.  The iconic pointed ends and most of the rocker that allowed Greenland kayaks to keep their bows above the waves in rough seas are sacrificed in favor of a much longer waterline for speed.  To replace the missing rocker and the up-swept ends, the bow was made much more buoyant by squaring it off and making it taller.  These efficiencies, the lack of rocker and extended hull length, allows surfskis to put their full length on the water and achieve a greater bow angle and more effectively harness the gravity off the face of a wave to add significant speed to the overall average.  Wave riding skills are an intricate part of surfski discipline.  Surf skis have no edging control, so secondary stability and chines in the hull that produce a distinct secondary stability are not required by surfski technique.  Instead, a smooth rounded hull is used to reduce the wetted surface, thereby further reducing water friction.  But this requires more technique and a strict discipline to keep them upright.  Stability is attained through bracing and proper posture centered over the keel.  Typically, the paddler will lean forward to utilize the strongest torso muscles with knees close together, head pointed forward, chin up.  A rudder provides all directional movement and must be available at all times.  Surfski designs increased rudder availability by relocating the rudder forward of the stern to keep it in the water on steep waves that often lift the stern.  Unlike kayaks, surf skis have not attained a payload capacity and serve a short duration paddling purpose.  Surfskis are very different from a kayaks and demand a different skill set and paddling style.  Surf ski Discipline, and technique has evolved into two primary goals: keeping upright, and maximizing forward thrust.  Sprint kayaks share a similar technique with surfskis on flat water.  A proper stroke is crucial: Blade entry, catch, and follow through.  Also important, is a technique to maximize the efficient transfer of energy to the hull.  Surfskis are paddled with a wing paddle.  Forward lean with strong torso rotation is needed to utilize the core muscles for a sustained strong drive.  Good technique will propagate the rotation to the seat and transmit the energy through the legs which pump up and down to deliver energy to the hull through the foot pegs. Surfskis are not rolled, but are easily remounted from deep water.

As the relentless persistence of science sculpted the kayak,  new designs took shape along the same path of technological optimization as the surfski.  However, the purpose of the kayak is very different.  Not primarily designed for speed, the kayak was created for much more practical purposes and survival, including transportation, hunting, and fishing in rough waters, requiring maneuverability, stealth, and high degree of seaworthiness.  The Inuits solution: a highly rockered, upward pointed hull ends kept the kayak from diving into large waves, but reduced the waterline of the craft which was not that important.  The pronounced "V" shape of its hull and chines had little primary stability, but added a reliable secondary stability. The pronounced rockered "V" shaped hull also helped these kayaks track straight, and turn easy with edging.  Greenland kayaks have no skeg or rudder.  However, the pronounced "V" adds wetted surface and water friction to the hull which is not a problem for the Inuit style kayak.   East Greenland kayaks were flatter with little rocker giving them more speed with a longer waterline, but were less suitable for rougher waters as the rockerless pointed bow did not have enough buoyancy to lift above the waves.  Greenland kayaks fit snug to the paddler allowing a more symbiotic relation between paddler and craft for easy, quicker edging control and rolling in the event of a capsize. However, they had little room for gear.  Unlike surfskis, kayaks do not require a highly disciplined posture and steep paddle angle.  A lower paddle angle allows a wide unobstructed view angle for hunting, fishing, and keeping other paddlers in sight.  Kayaks can be righted with a brace or a roll.  Historically, the Inuits had no method for reentering their kayaks, since being separated from one's kayak meant certain death in the ice cold waters.  Their very lives relied on their rolls and other righting skills.  Modern kayaking allows the wet exit as a last line safety measure, in turn several methods for kayak reentry were added.   British style kayaks brought the kayak to the masses, while attempting to retain the spirit and characteristics of the original Greenland design.  The symbiotic fit is exchanged for a high volume hull to accommodate a generous amount of gear and paddlers of all shapes and sizes.  Thigh braces restore some of the body extension fit of Greenland kayaks.  West coast kayaks from the western American coast similarly retain the pointed bow and rocker, but add a rudder to a flattened stern to reduce weather-cocking in the high winds of the western American waters.

The designs and techniques of kayaks and surfskis evolved separately and are very different.  As they differ in their purpose, their benefits are mutually exclusive to each other.  Paddlers are left at a fork in the road to decide what they want and what they are willing to live without.  Similarly, their circles of paddlers are divided along the same lines.  Slowly, kayak manufactures started dabbling with design aspects of both paddle craft, adopting bits and pieces at a time.  To make a truly hybrid design was a difficult task fought with several technical challenges.  Moreover, they each require different skill sets and disciplines.  Kayak manufacturers began to adopt a very limited number of surfski features, yielding limited gains since these features on a kayak could not be paddled in the manner for which they were originally designed.   At Epic Kayaks, the two founders,  both surf ski champions, over a period of years, ventured so far as to entirely do away with the kayak hull in favor of a swede style surf ski hull in their 18x and 16x models, resulting in kayaks that bare little to no resemblance to their traditional roots, and perform far different than kayaks of Greenland lineage.  They were not the first to try this, but they went further by designing every facit of the craft to give surfski and kayak paddlers what they need to paddle the kayak in the manner befitting both crafts.
 
To satisfy surfski paddlers a reliable rudder that stays submerged and engaged in heavy waves was needed.  While a bottom mounted rudder works quite well for both uses, it cannot be retracted and is therefore unsuitable for most kayak purposes.  The most difficult task for Epic was coming up with a rudder design that would satisfy surfski requirements and fold away to preserve a kayak experience.  Their solution led them down a path to a rudder design unlike any other.  The stern of the hull was severed and turned into the movable portion of the rudder, housing a retractable spring loaded surfski blade, which could be extended from the bottom, forward from the stern.  When not used, the blade retracted into the stern section which in turn, locked into the center position to become the ridged stern of the kayak.  Their solution raised eyebrows in the industry.  While not a perfect surfski rudder, it went a long way to satisfy requirements of a hybrid craft and solved a long standing rudder problem of surfskis and kayaks with a spring retractable blade that moves out of the way when hit by an obstacle, and returns to place when the obstacle was gone.  Obstacles cause standard kayak rudders to kick up and not reset.  Standard surfski rudders just break off unless a stern mounted surf rudder is used.

Epic also did away with the iconic pointed bow and stern of a kayak in favor of the swede surfski hull with an elongated water line and a large  buoyant bow to keep it from burying under the waves.  The large single continuous foot brace facilitates energy transfer through the legs, and elongated cockpit coaming to allow the paddler to easily paddle the kayak like a kayak or surfski/racing K1 with plenty of room to extend the knees through the opening of the coaming enabling the paddler to pump energy into the hull with the legs and rotate down to the seat.  Padded knee holds just under the coaming sides allow the paddler to quickly switch from a surf ski posture to brace for a roll in the event of a capsize.  For a more kayak feel, the seat could be slid forward to allow a smaller paddler's legs to go further under the deck to better contact the hull for bracing and rolling.   Epic designed the seat to retain the functionality and feel of both a kayak and surfski, with smooth bare contoured fiberglass, allowing the surfski paddler a smooth surface to rotate on the seat to engage the lower back muscles and drive energy through the large foot brace.   Like many greenland style kayaks and surfskis, the back is low with little back support.  There is a lumbar pad for the lower back that does an adequate job of support while allowing a good layback roll.   Paddle blade cut-outs on the forward deck were added so the surfski paddler can initiate the catch phase with a vertical stroke close to the hull.  For the kayaker, the craft performed like a kayak responding well to edging, and very easy to roll.  However, as the large coaming provides the surfski paddler with extra room, this further reduces the symbiotic relationship kayak paddlers have with their kayaks, leaving the kayak paddler to alter their bracing technique to grip the undersides of the large coaming with the knees.  The large coaming may also let the paddler come out of the seat during a roll if the paddler does not sufficiently brace their knees against the sides of the cockpit.  To compensate, Epic heavily padded the underside of the deck around the front and sides of the cockpit.  They also put the seat on an ajustable track.  With the lower wetted rounded hull design, the kayak does not hold its course as well with the rudder up, but the rudder is extremely effective in all conditions.  The surfski paddler has what is needed to assume a proper posture, paddle stroke, plus a  reliable forward mounted rudder.  The hull responds like a surfski hull in the sea as it is able to catch waves and not bounce from the bow in rough seas like a high rocker kayak.  The rounded swede hull will likely unsettle beginner and intermediate paddlers initially in rough conditions with its much lower primary stability.  However, when loaded for an expedition, the kayak is quite stable, and rides comfortably at the expense of much of its blazing speed when riding empty.  To capture a little more secondary stability, Epic flared out the gunwales above the waterline behind the cockpit at the widest point of the kayak where the secondary stability emanates.  If the kayak does capsize,  it rolls very easily.  Paddlers of all types will enjoy being placed closer to the water as surfski paddlers expect for their vertical stroke since the cockpit is at a narrower point in the hull.  The 18x is not a beginner kayak, but is one a paddler can grow into and not outgrow.

For expedition use, the kayak rides very stable in the water.  The elongated cockpit makes it very easy to exit and enter.  The newer latch style hatches hold tighter and keep the compartments dryer.  They are also very easy to open and secure shut.  The hinged day hatch is especially convenient which stays fastened and has only one latch.

In an industry with hundreds of kayaks of different shapes, sizes, and specializations, the introduction of a new quirky looking design hardly raises much notice.  However, in 2009, paddler Frya Hoffmeister circumnavigated the continent of Australia (8570 miles) in an Epic 18x sport, and shaved more than a month off the time of the only other previous successful attempt by Paul Caffyn.   The paddling community finally accepted the Epic 18x as a serious expedition kayak and began to debate the merits of fast expedition kayaks.  Epic later went full circle and introduced the V8 surfski which adds a surfski top to the "18x Sport" kayak hull.  While this new kayak could never be the perfect solution or satisfy all the intricate demands of both types of craft, it did integrate the spirit of both a kayak and a surfski in an interesting way.  Harnessing all the benefits of this design will place extra demands on the paddler to expand their skill set to encompass at least a subset of kayak and surski techniques.  For their efforts, the paddler can wield a full featured kayak with the speed and prowess of a surfski when empty that settles down to a stable serious expedition kayak when loaded.

These are exciting times to be a paddler with advances in water dynamics and the melding of kayak and surfski technologies.  Only the future will tell if the Epic design will stand as a milestone in the evolution of the kayak, or be seen as a first deep foray into the realm of a true hybrid craft.  Several kayaks have penetrated the market utilizing aspects of both technologies in their own creative ways.  With the success of the Epic 18x, we will certainly see manufacturers committed to produce more hybrid type craft to take paddlers farther and faster.  Along this journey, paddlers will find they too must evolve to meet the skill set demands of these new craft.  Farther down the road refinements will likely mainstream hybrid design kayaks and push kayakers farther away from a 4000 year old legacy and discipline into one created for the modern age.  Only the future will tell if the traditional kayak will fade into irrelevance and be relegated to the romantic fascination of a few.

Copyright 2012 Lyman A Copps

Sunday, November 11, 2012

Kayaking with the Big Kids




Several years ago, I wanted to skill up so that I could do more open water paddling, I ran in to a Catch-22. Most of the recreational paddlers I started paddling with weren't interested in ocean paddling, and the more skilled paddlers I knew routinely closed paddles to those they determined to be "less skilled." I don't think it helped that I was a woman and that most of the sea kayakers were guys. For a while, I felt like I had to drag my husband out on every paddle with the "serious" guy paddlers as some sort of chaperone to prove to the guys and their significant others that I was actually there to kayak.* I found it to be a truly miserable time. I tried to recruit folks from my rec kayaking community to skill up without success and I had limited success "breaking in" to what began to feel like the "big kid" paddles. 

So how did I blast through the impasse? Well, two ways. First, I went out and skilled up the best way I knew how: I routinely invited those paddlers I knew to be more skilled on paddles that I planned. A lot of the time, I didn't know what I was doing. Some of them very rightly told me that, but I was not to be deterred. Once some folks determined that I was determined to get on the ocean, others took the time to correct me AND to offer the resources on where to obtain the correct information. They referenced great resources like saltwatertides.com, leant me nautical charts, and offered insight on the local knowledge they had gained over the years. Most importantly, a few excellent kayakers even began going out with me on the water, then the trips I planned, and supported me in ocean trips even before I knew how to roll. 

The second thing I did was actively work to develop my skills in more formal settings. I found instructors I worked well with and sought out their knowledge. I found that I worked very well with teachers who could clearly demonstrate, who did not overwhelm me with excessive talking, and who had a kind and gentle good humor that kept a nervous learner eager to learn. I almost gave up kayaking after a negative first experience, but Lamar Hudgens at Barrier Island Kayaks showed me that I could do the things I wanted to do AND have a great time. As a result, I've bought two kayaks from him and gone to numerous symposia at his shop.

One very important lesson I learned was that the more skilled kayakers weren't shutting me out of fun trips and adventures because they were cliquish. They were shutting me out because they feared for their safety and the safety of the group. A solid, skilled group of paddlers can only support a few who are less skilled--it's simply a matter of safety. For instance, I planned, or tried to plan, a trip to circumnavigate Bald Head Island in 2009. It was tough for me, even once I got more skilled paddlers to come along; the strong personalities of folks and what I interpreted at the time as an "officious" tone nearly drove me to cancel. But I stuck it out, and as a result, I got to do my first real ocean journey of 20 miles around the Cape of Bald Head.

So where does safety come in to the story? Well, in lots of places. I discovered on that trip that even the skilled paddlers had limits and they (and I) weren't yet aware of mine. They sometimes capsized during surf landings; they didn't always adhere to plan and sometimes took off on their own; some didn't pack enough water. On this trip I discovered that I become violently seasick in ocean swell. I also learned that I could paddle through 5 foot swells, vomit 20 times, and paddle ten miles without bailing out. (Now, seasick medication keeps me happily afloat.) I can't say what the others learned, but I learned I was a lot tougher than I thought and that the "big kid" paddlers still had plenty to learn too. That heartened me considerably. They didn't know it all. They simply knew more than I did and had more practice. With classes and people to practice with, I knew I could learn what they had.




So, if you're new to skilling up, take heart and be persistent. And if you're more skilled, remember what it felt like when you weren't and invite those who are lesser skilled on some of the more challenging, technical paddles. That way, our community continues to grow and to flourish.

Dawn S's account of the Bald Head Adventure is here:Bald Head Island

*My husband became an excellent kayaker in the process. :)



Thursday, November 8, 2012

Who Are You?

Guest Contribution:
Virginia


Kayakers kayak for different reasons: some of us love to kayak on glassy water and drift along quietly;
some of us like to kayak down rivers; some like to cover lots of miles; some of us like a bit of whitewater; some of us like surf and swell.




In a big community like CKC, it's important to remember that what often works well for one paddler might not work at all for another. Luckily, we mostly know one another from trips, symposia, or the CKC forums and so we are respectful, generous, and kind.

Whatever your kayaking interest, you'll often find at some point you want to “skill up” a bit. Before you sign up for a class or symposium, do some homework on yourself and some fieldwork on your chosen venue and instructor. This can help you spend your hard-earned money wisely and emerge more satisfied with your learning experience.

First, ask yourself what sort of student you are.

Do you do better one on one than in a large group? If so, individual lessons might work better at first than a symposium class with 8 students.

Do you tend to be a thinker and need to understand things theoretically prior to attempting to execute them? Or do you tend to just want to watch and then do? Make sure that both you and your instructor know this in advance. Then you can help your instructor create the best class for your needs.

Do you have any fears? This is important and often overlooked.
For me personally, I wasn't told by the first company I trained with that I was going to learn wet exits with a sprayskirt on. I'd been bullied and trapped underwater as a kid and the idea of being upside down in a skirted kayak seemed overwhelming. Luckily, my instructor (Robert Smith) just sat with me through it, and was reassuring, so it all worked out. But it would have been better if I had known to get details on what would happen that day and to clearly disclose my fears. Now, I'm happy as a clam underwater, but it took me a long time to feel at ease. I need instructors who are patient and not punitive. Now, I seek out those I have heard are patient and encouraging and quickly discard those that are not. It's just what works for me.

Do you have any physical limitations? If so, let your instructor know. Many instructors also have adaptive skills training.

Then, ask yourself what, specifically, you hope to gain from the class. It helps to clarify your goals.

Perhaps you want to be able to turn your kayak with ease in the wind.  Perhaps you want to learn to climb back in your kayak. Perhaps you want to learn to roll. Perhaps you want to learn to surf.



These are all great things to learn and all of them take some time to master. You might dip your toe in at a symposium and get a taste of each. You might take one class a time, then go off and practice with your kayak friends from CKC. For me, I like to learn one thing at a time.

Finally, get some local knowledge. Ask others who know you and whose skills you admire which instructor they think would be a good fit for you.
Look at the kayak forums and websites. Who is more structured? Who tends to be gentle and soft spoken? Who tends to demonstrate strokes clearly and effectively? Who is excellent at navigation? Who is an excellent rolling instructor? Once you've selected a teacher, try to talk with them a bit beforehand.




Teachers and students are individual. A great fit is key to both developing your skills and enjoying learning.

Wednesday, November 7, 2012

Campfire Stew

This is a tradition with me, as long as I have been camping.  It involves me tossing it together while I pack my gear, boats and car the night before a trip.  By the time the car is packed, the stew is ready to head off for the first night of camping.  Usually, the first night involves settingup camp, possibly unloading a boat, finding out where things are.  This is the night for something that can be heated up and eaten right away.  When I have brought this, it seems like many people have a variation on this theme, and tell me about their ideas.  Here is mine.
Saute 2 pounds of hamburg.  Drain well. Saute one huge Vidalia onion up in the leftover oil.
Add 1 bag of frozen green beans, one bag of peas, 2 bags of corn, two large cans of diced tomatoes,
When adding herbs, I always prefer fresh, but use what you have.  Add 1 1/2 tsp. of thyme, oregano, basil, margoram, black pepper and salt. Simmer and adjust seasonings. 
This is very simple, but everyone always eats it--hearty and practical, and good for camping.

Tuesday, November 6, 2012

Lessons Learned from Surfing

SURFING SEA KAYAKS!

There's probably nothing more fun (to some of us adrenaline junkies) than surfing the perfect wave.

That said, and after a surf day that was chock full of lessons learned from observation, I'd like to share these pointers.  Please feel free to add your own comments and knowledge!


·        Assess the waves when you arrive first.  Are they dumping?  What is the timing between them?  What are the conditions?
·        Assess the beach –
a.      Piers? Jetties? Obstacles?
b.      Crowded with people?  Is it safe for them if you surf?
·        Assess the weather
a.      Wind – which direction and where will you get blown
b.      Rip current formed by strong wind?
c.      T-storm likely?
·        Assess your kayak surf group
a.      Skills
b.      Safety
c.      Courtesy
·        Rules
a.      No ‘parking’ down wave of another kayak
b.      No rescues in the surf impact zone
c.      After riding a wave, turn and make a loop out of the ‘flight pattern’ of other kayakers
d.      Be alert for swimmers and surfers on the wave, and do not snake their wave
·        Surf  exit
a.      Stand ocean side of the kayak
·        Getting dumped in the surf
a.      Get on the ocean side of your kayak, not the beach side
b.      Do not put fingers in the toggle loop
c.      Let the kayak go  – you’ll dislocate or injure your shoulder or hand attempting to hang onto it
d.      Do not attempt a ‘pole roll’ near the beach…another good way to injure a shoulder
·        Rescues in swells or at sea
  1. Be Careful!