Surfing at an angle (to waves)

[josko]

<p>I'm becoming comfortable surfing downwind in wind waves; a favorite trip is from Woods Hole to Cuttyhunk in the morning, and then surfing back downwind in the afternoon seabreeze. I've been able to average ~6-7 knots for the return leg in ideal conditions and am having a blast linking waves and learning to keep my speed up.  </p>

<p> </p>

<p>I'm generally fine if my destination is within 15 degrees of dead downwind.  If it's at a higher angle, say 30 deg. (to dead downwind) my boat tends to broach, and in general, I have a hard time tracking in the desired direction.  I've fiddled with my skeg, various rudders, draws, and positioning on the waveface, but am still having a hard time.</p>

<p>What can I do to learn to get better at downwind surfing at increasing angles from dead downwind. FWIW, my primary downwind surfing boat is my P&H Bahiya, but I have the same problem in my NDK Romany Surf.</p>

[rick stoehrer]

so surfing perpendicular up to 30 degrees or so of center, you're doing great and then beyond that...bongo city?

surf specific kayaks have a hard rail or edge, very similar to a surf board. most sea kayaks don't have this feature and they're a whole lot longer...so once that sea boat starts to purl, it's really tough to bring it back and often, you don't...if you can make turns up to 30 degrees and bring it back to center, you're doing great.

i don't think there's a specific trick or technique beyond where you're bringing the boat josko...i think that's just the nature of the boat you're using.

[John Martinsen]

Try zig zagging?

[josko]

So, if the desired course is, say 45 degrees from the wave direction, what's the best strategy to cover water? Surf downwind and then ride in the trough?

By the way, do rudder boats and/or surfskis do better when surfing at an angle?

[rick stoehrer]

so you aren't out thrashing in surf, you're riding wind waves to get somewhere...travelling. not that it makes much diff...sea kayak is a sea kayak...no rails, no hard edge to cut/carve into the water. i guess i'd make my way over best way i could...maybe try to get a lot of it in "up top" and then enjoy the rides down? dunno...don't think there's a right or wrong way.

depending on whether or not you can keep the rudder in the water, you might have more success with a ruddered boat...with some of them with the over the rear rudder at the very stern, they can come out of the water and you'd face the same issue...under hull rudders like on a surf ski will stay on the water better but you've got to take more care launching/landing.

[JohnHuth]

I zig zag in that situation - typically try to catch a set, and then just plain paddle to regain my heading, then catch a set again. But, that's me.

[josko]

I think surfing at high angle in a sea kayak is doable, but requires a set of skills I don't (now) have. I'm catching myself with longer and more controllable high angle rides, and am starting to be able to identify and isolate what caused a particular broach. My motivation is to be able to surf Vineyard Sound and Buzzards bay in a Broader range of wind directions than I now can, and am curious whether other people had come up with the same problem and had been able to address it.

IMHO, surfing and then riding the troughs is the pits! There's got to be a better way.

[kate]

I zigzag too, surfing and then turning and going back into the waves (which is more enjoyable than riding the troughs) and then surfing again. Little by little, headway is made, and it's mostly fun. As for finding a way to maintain a high angle - I agree with Rick that the boat makes a difference, and that there's a point beyond which no boat can go. Fun to keep exploring that edge though!

[Phil Allen]

Josko-

You may have considered this, but at some point the physics gets in your way. The paddler needs to accelerate to approximately the traveling speed of the wave to "catch" it. As you change the direction away from perpendicular to the wave front, you "lose" speed in the direction of the wave and add it to the sideways movement (not a linear relationship). I'm not sure exactly when, but I dont think it would take much of an angular change to reduce the forward component of the speed such that you can no longer match the forward speed of the wave.

If you watch the surfers, they accelerate down the wave, and then turn off to run along up and down the wave face. Same with short boat surfers. While long boats have greater speed than short boats/boards, it's the shorter boat/boards ability to climb back up and then run down the waves that allow them to travel long diagonal distances.

best

Phil

[leong]

You may have considered this, but at some point the physics gets in your way. The paddler needs to accelerate to approximately the traveling speed of the wave to "catch" it. As you change the direction away from perpendicular to the wave front, you "lose" speed in the direction of the wave and add it to the sideways movement (not a linear relationship). I'm not sure exactly when, but I dont think it would take much of an angular change to reduce the forward component of the speed such that you can no longer match the forward speed of the wave.

Quite true, Phil, it’s nothing like a linear relation. To match the speed in the direction of the wave, your forward speed would have to be inversely proportional to the cosine of the angle between the direction of the wave and your heading direction. To demonstrate with numbers, the table below shows how fast you would have to paddle (assume the phase velocity of the wave is 8 knots):

Wave to heading angle Paddling speed in your heading direction

0 degrees 8 knots

30 degrees 9.2 knots

45 degrees 11.3 knots

60 degrees 16 knots

75 degrees 31 knots

Leon

[josko]

I spent some time practicing angled surfing this weekend in fairly small stuff. The 1/cos(angle) wasn't a huge deal; what was getting me was the difference in orbital velocities between the trough and crest. That is, water at the wave crest is moving faster (downsea) than water in the troughs, and that tends to torque the hull broadside. Wth edging and sweeping I could just maintain an angle up to ~45 or so, but it was constant work.

I was also noticing that at slower speeds, my boat (Romany Surf) responds well to outside edge- edging, but when it starts planing, It wants to carve on the inside edge. As i (slowly) got the hang of it, it seemed that the way to recover from a too-high angle (incipient broach) was to build up boatspeed and really lay the boat over on the inside edge. About half the time, it would bring me back into control and angle I wanted - I wonder if I was freeing the bow and stern from the adverse water forces acting to broach me. The other half of the time, well, my roll got better.