Been using a wing for about 10 years
First, let me say that I’m not a lily dipper. When I get in any of my boats, first thing I do is turn the GPS on and off I go. I enjoy paddling at speed and the exercise for me is important. The wing paddle, I have 3, forces me to paddle correctly, the GPS tells me when my technique is incorrect. The three ONNO wings I have are all different lengths and blade size, all two piece and feather and length adjustable. All are extremely light and the wing I choose to use is dependent on the boat I’m paddling, be it surf ski, sea kayaks and I use a wing on my solo canoe. At my age of 64, I can still paddle much as I’ve done in the past, as I age, no doubt my strength will diminish…but not yet!
Eureka! I better understand thrust force
as result of your clear and simple explanation. I use GP for 7 or so years now and with what some have described as a good wing stroke. Was not deliberate effort, just evolved to what felt efficient to me. My current 2 sticks do have the lenticular shape. CF one with sharper edges appears to have more bite (thrust) than cedar with more rounded. All I know is they work for me with all strokes and braces. And my aging joints creak less.
source of improvement
Great explanation. I would only add that while the lift generated by the outward motion of the wing provides the efficiency increase over a Euro, the largest portion of the total thrust still comes from drag of the paddle. Same as with a Euro.
Interesting
You seem certain that drag predominates - not implying you’re incorrect, just curious how you know that. I haven’t used a wing enough to come to any conclusion - I dislike them in general.
no proof
I cannot prove it so I am not certain, but my clear sense is that the drag predominates. If I lower the wing stroke so that the leading edge is more toward the sky, I get only slightly less power than when the leading edge moves outward. That slight improvement (my guess is about 10%) comes from the lift and makes all the difference in getting that extra few tenths in speed.
no proof
I cannot prove it so I am not certain, but my clear sense is that the drag predominates. If I lower the wing stroke so that the leading edge is more toward the sky, I get only slightly less power than when the leading edge moves outward. That slight improvement (my guess is about 10%) comes from the lift and makes all the difference in getting that extra few tenths in speed.
Hmmm
…I find this very interesting - will have to think about how to assess it qualitatively as you have done.
I’m sure the finite size, odd shapes and highly variable path of wing paddle blades through the water give a wide continuum of behavior, from fully drag-based to highly lifting. I’m guessing a wing might even be counter-productive if not handled correctly.
NASA’s Al Bowers on Wing Paddle Papers
Do Check it out:
http://www.surfski.info/reviews/item/271-wing-paddle-papers.html
Also interesting
Revealing quote from the first paper:
“More successful paddlers entered their blade well forward and closer to the longitudinal axis of the kayak than did less successful paddlers, and moved the blade a large distance laterally from the kayak and only a small distance backward with respect to the water.”
how I think about it
In order to generate lift the flow has to be parallel to a chord. Now at the catch, after full immersion with a vertical blade, the chord is perpendicular to the long axis of the boat and parallel to the water surface. If you were to force the blade straight back (difficult to do with a wing blade), there would be no lift at all. Only if the blade is allowed to move outward from the hull is there flow along the chord. But you are still pulling back with the blade still very much a drag device, but with some additional lift. Note that this basic drag is normal to the induced drag, i.e., the drag due to lift. In other words, the induced drag is not helpful at all. Propelling you forward is the drag of the drag device, plus the lift.
Got To Remember This Was In 1992
And the lateral or “skating” type stroke was in vogue. Eventually with practice and newer wing paddle design, paddlers were able switch back to the old parallel (straight back) stroke. The blade no longer fluttered underwater doing so, and is controllable. Of course, this doesn’t happen overnight, for it takes practice. Somehow, feather angle does play a role in this, for I find that I have no problem going straight back at an 80 degree angle, but immediately capsize when I reset the feather angle to zero degree.
Depending on fatigue and the water, I like to use a combination of both lateral and parallel strokes. Either high angle when I want to accelerate or low angle for just cruising.
Perhaps More Revealing Was
Under Editorial Comments:
“Some of the “slip” in Sanders paper is due to the removal of the paddle from the water (a part of the exit) and may actually contribute to the braking on each stroke because the paddle is not being pulled aft at the exit of each stroke.”
After reading this, I now understood why a member of the U.S. Olympic Team, at a wing paddle stroke clinic in 1995, told me to "pull all the way back (past the hips) on my stroke. I thought the advice was odd and contrary to prevailing custom of removing the blade before the hips.
Oh! Well, perhaps the wing works better as a pump and to strive for lower Struhal numbers?