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leong

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    Kayak racing, fishing and touring; road bike racing and touring; ski touring; swimming and fitness workouts.
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    Paddle Upwind

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  1. Paul, The other reason I always entered the 6-mile race is there are no portages. The last thing I wanted to do was carry a $3 thousand kayak and run with it.
  2. Hi Paul, I used to race the six-mile event because the start and finish are in the same place. Long time no see. I do most of my paddling in southeast FL now. Leon
  3. https://nypost.com/2023/05/15/huge-tiger-shark-bites-kayak-off-hawaii-coast-in-wild-video/
  4. Mostly to eat the regular sized sharks. Read about it here: https://www.sun-sentinel.com/news/environment/fl-ne-great-white-sharks-return-20221128-4igrqfugbfga5ldahwfzhjptaq-story.html?utm_source=newsletter&utm_medium=email&utm_campaign=Don't Miss&utm_content=5601669677945
  5. Here he is landing: https://www.facebook.com/CyrilDerreumauxAdventure/videos/1505217906596163 Nice extra long wing paddle.
  6. The use of kayaks for clandestine military operations goes back as far as World War 2. Especially the British commandos raiding German shipping at Bordeaux by sneaking up the river in 2-man kayaks in order to plant magnetic mines on ships in the harbor. I wonder if kayaks are used by the Ukraine defense forces? https://www.mensjournal.com/adventure/commemorating-daring-world-war-ii-kayak-raid/ https://www.bbc.com/news/uk-england-suffolk-57205877 https://www.americanspecialops.com/boats/kayak/
  7. >>Most GPS “backcountry nav” phone apps including Gaia GPS do have some version of the feature Leon is talking about." What I'm talking about is not a feature of a GPS no more than a steering wheel is a feature of an automobile. It's just how a GPS works. You don't have to add anything fancy to it unless it gives you something more useful.
  8. I just found a similar thread I posted back on 8/7/13. Perhaps this text that I posted then will help clarify this new topic I started: The GPS knows the kayak’s location and the waypoint’s location in some fixed earth coordinate system. It doesn’t know its own orientation (what direction it’s facing or even if it’s pointing backwards or straight down). It also doesn’t know the heading angle of the kayak. But it does know the Course-Over-Ground (COG) that the kayak is moving along as you paddle and drift with the wind and current. If the COG coincides with the beeline from your present location to the waypoint, the GPS’s arrow (at least it’s an arrow with my GPS) points to the top of the screen. If the kayak’s COG for this latest update is to the left of the present beeline, then the GPS’s arrow points to the right (indicating that you should change your heading to the right), and vice versa. Of course, your COG is the result of the vector sum of the kayak’s forward speed and the cross-velocity vector due to current, wind and wave action. So, the GPS doesn’t really have any idea of current velocity (I mean water speed and direction) or wind or anything else that’s pushing the kayak. All it really knows is the COG and the latest beeline to the waypoint. If you try to keep the arrow always pointing to the top of the screen (via heading changes as necessary) you will be following a straight line to the waypoint.” I also said in response to someone’s question: The arrow doesn’t point to the waypoint. It shows you whether your current COG is to the right or left of the COG to the waypoint. But when the arrow points to the top of the display your current COG corresponds to the COG to the waypoint, but it's not pointing to the waypoint. I’m mentioning the arrow because that’s what I use with my GPS. There are other screens like a line on a map that do the equivalent. Also note that any GPS compass must be disabled.
  9. You're right, Joseph - can't argue with that. However, the point of my post was to make people aware of how a GPS really works. You don't need a phone or a phone app. Just (as in my picture) keep the arrow pointing to the top of the display and there is no need to think about any variables like ferry angle, wind velocity, current drift velocity or paddling velocity. The geometric physics of how a GPS works eliminates all of that. So, in the "goto" waypoint mode the GPS allows you to keep your velocity vector (course over ground velocity) directly on the straight line to the waypoint no matter any side movement caused by wind and/or current. The GPS doesn't know anything about the heading of your kayak, it just knows your velocity vector. Nevertheless, I don’t know, but the Gaia GPS phone app may add some information useful for the paddler. I hope everyone now realizes that the complications of ferry angles become irrelevant when you use a GPS. However, I'm all for knowing how to use ranges and estimating ferry angles.
  10. Jim, I’m not sure you disagree and I don’t agree your way is very simple because it underutilizes the way a GPS works. First some essentials of a navigation GPS (turn off compass if it has one): The GPS knows the lat/long of where it is and it knows velocity it is moving (speed and direction). Say you enter the location (lat/long or whatever map coordinates) of the place you want to paddle to; i.e., the way point. Assume, like in your example, it’s a foggy night, but also assume that the wind velocity, current velocity and paddling velocity are variable (Note velocity is speed and direction). 1. You could estimate your paddling speed, the changing cross current speed and the changing cross wind resultant cross drift speed and do some complicated arithmetic to compute your ferry angle. Of course, it will change in accordance with the changing the wind velocity cross drift and current velocity. 2. You can do as you said which will work fairly well even with variable wind and current velocity. Now here’s the easy and most accurate way to paddle to your waypoint (don’t forget to turn off the GPS’s electronic compass): Just paddle so the arrow in the GPS compass page (see picture) is always pointing to the top of the display. After a while if the arrow is a little to the left of the top just paddle a little to the right to bring the arrow back to the top of the display. Similar for a right correction. Note some GPS models use a page with a straight line and a dot or something to keep on top of the straight line. What could be easier and more accurate than this? In essence, the variable current velocity, your variable paddling velocity and the variable side drift due to variable wind velocity are all implicitly taken care of by the way a GPS works. The GPS doesn’t have to calculate any of the variables and use them to calculate a variable ferry angle. I use this method whenever I paddle back from the Isles of Shoals to Little Harbor. It so good that on a windy day with a strong tidal current It would take me into the harbor’s inlet even just by following the GPS. Of course, one should know how to use ranges, calculate ferry angles and use a compass.
  11. Then again, a GPS knows nothing about cross winds or cross currents and wouldn’t know a ferry angle from a ferry boat. So how does it help you keep your "course over ground" on the straight line from your position to the waypoint you desire to go to? It cares nothing about its orientation; i.e., it even works if you point it up or point it down or face it backwards.
  12. I hope you realize that you don’t need to concern yourself with ferry angles or ranges when you are using a GPS that is reliably working. Of course, you should be familiar with ferry angles for when you won’t or can’t rely on a GPS.
  13. To each his (her) own, I guess. Like I enjoy pedaling my road bike, I enjoy forward stroke paddling as much as the destination. Depending on conditions and paddling partners, on my dozen or so paddles out to IOS, my one-way times varied between 1:12 and 1:30 (except on one return trip in heavy winds and rough water it was over 2 hours).
  14. Same with a normal rocking chair (with curved runners) that works for everyone with no learning time required. Of course if it has short flat runners it has good primary stability but no secondary stability. Also, a keel on a sailboat provides no initial (primary) righting force but has increasing secondary righting force as the boat heels.
  15. https://oceanconservancy.org/photocontest/?ea.tracking.id=21LPFNEAXX&utm_medium=email&utm_source=engagingnetworks&utm_campaign=monthlynewsletter202106&utm_content=20210603-MonthlyNewsletter-Prospects-Email1B-21LPFNEAXX
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