Jump to content

Spoonie

Members
  • Content Count

    749
  • Joined

  • Last visited

Everything posted by Spoonie

  1. Flappy sails are unhappy sails... most of the time... ...I'm actually qualified to tell you that.
  2. I think from memory, the safety at sea training calls that keeping warm.
  3. I have a thirty footer. Ronstan dinghy extension works just fine. If you're halling that hard on the extension you have other problems.
  4. And that's fine, but two yachts on a pleasure cruise heading in two different directions in what sounds basically like open water should never be in the position they need rules to avoid bumping in to each other. There are two fundamental principles I live by out on the water: 1) I have ultimate control of what my vessel does and does not do 2) until proven otherwise, the other guy is an idiot, act accordingly if you don't need to be in the same corridor then don't. If you do, make your intentions clear, loud, and early, and only assume the other guy will respond if t
  5. Where T.F is Cid Harbour? I mean, i grew up halfway between brisbane and hammo, thought I had sailed to most places on that strip of coast. Never heard of Cid Harbour. Gladstone or Keppel would be about half way. A few sharks, and less crocs but just as many box jellies as Airlie...
  6. Yup.... Always assume the other boats will do something stupid and act accordingly, Ideally well before you need to.
  7. I dunno, it sounds like the other boat is being precious to me. Assuming both boats are keeping a proper look out then the risk of collision should be low, unless one or boat are limited in manoeuvrability. If you are looking out, then you have to assume the other person isn't. you're both out for a casual sail, it sounds like it would have really been no skin off the other guys nose to pinch up a bit for a ways out to make sure it was a safe crossing. Also, they don't know if you're stuck on a particular heading so can't manoeuvre. IMHO if your are pulling the colreg
  8. PS, I'd be stoked to have a boat called a Navier...
  9. technically, a solution can still be trivial even if the problem is difficult or complex. It is probably more correct to relate non-trivial to complicatedness. just say'n...
  10. Well there you go. that makes sense. the way I think about this is to imagine bending a batten. If you take a batten and bend it , it forms a fair curve. If you push that curve one side or the other, one side becomes more round, and the other becomes more straight. If you bend the batten more the distance between the two ends gets shorter.
  11. Depends on what the other settings are. Someone is trying to induce bend lower down the mast. Typically that results in a straighter mast from the spreaders upwards. Means a flatter main at the bottom but fuller mid and top sections. Also might result in less forestay tension as the mast compresses so your jib knuckles up. Where as tight D1's result in a more rigid lower section pushing the bend further up the mast. That means the mid/head of the main is likely to flatten more and the forestay remains tighter, so a flatter jib. I'd say, and I could be wrong, the 7 setting is
  12. This is another one of those "a good coach in a coach boat would probably see the problem in about 15mins" type problems. Let's assume the performance difference is real. And that when trimming both sails, exactly the same way on one tack over the other, and sailing the boat exactly the same way on both tacks, you get a bubble in the front of the main on one tack and not on the other. This means one of two things: 1) the pressure at the front of the main is higher on one tack than the other 2) the angle of attack of the main sail is different on one tack than the other
  13. I think that was my comment in the other thread. The first rule of instruments is they're probably wrong. The 2nd rule is...
  14. While this may be true, it is very much a guilty until proven innocent thing. Having "on the balance of probabilities" decided you haven't sailed the course, the onus then falls back on you to prove otherwise. Any PC would invariably face a level of bias against and/or under value any new evidence presented in a protest room. The first determination will have a greater bearing in their minds on the outcome. It's the same reason fake news sticks so well. It's hard for someone to make a new determination on something once they have already learned or decided on an existing one. Espec
  15. No it's a problem here too... Especially old boats on moorings, surveyed or not. Might be better now I don't know but after every storm here it seems like the insurance goes up as random mooring minder X washes up on a beach and takes a few more expensive boats with it.
  16. On a 24' 1T boat, I think the pros would have looked at the numbers and turned the instruments off by now. Fundamental rule of computational systems though, always compare what the computer is telling you against reality. Plenty of plane crashes (and the odd shipwreck) have happened because the pilots believed their instruments first and reality second.
  17. If your instruments are telling you you are 40% off and 10-20deg down, you need to stop doing that. Go back to basics and sail the boat. Get some other reference point; an analog compass, other competitors, hand held GPS. Without sog and cog numbers, I'm willing to bet you're sailing your boat into oblivion because your instruments are telling you to.
  18. ^^^^^This^^^^^ I mean real simple question from this, have you used an independent hand held GPS to measure SOG on both tacks? is the difference more pronounced when the boat is healing (upwind) vs not (downwind)? When you are sailing against other boats, do you get disproportionately smoked on starboard tack? 40% off is a lot. If that was real, you would certainly know about it as other boats whizzed past you. First rule of instrument based systems is they're probably wrong. Second rule of instrument based systems is... well you get the idea. IMHO People get too fixate
  19. Actually, it is really easy to define. surfing is the act of falling forwards off a wave. Planing is a hydrodynamic state. The point is not to get hung up on it. A boat that is planing is planing, regardless of how it got into that state, including whether it got there by surfing. It is perfectly reasonable for a boat to fall off the plane when it stops surfing. That doesn't mean it wasn't planing. where the confusion lies is when you try to make it an either/or thing when it isn't. They are two seperate things that may happen to overlap through consequence o
  20. So... I've somewhat found this thread painful to read. I don't know why I'm still reading it. But here we go... There are three fundamental hydrostatic forces on a sailboat you need to worry about. The amount of water it pushes downwards, the amount of water it pushes forward, and the surface friction of the water across the hull surface. Newtons third law, any water the boat pushes, will push back in the opposite direction. To which We basically have two vectors: One pushing up, and one pushing backwards. If the one pushing up reduces the one pushing backwards (through hull des
  21. I do feel like we could turn this into another version "hot or not" .... so Planing or Surfing? Hint, it's a trick question:
  22. Hold on and hope? Judging by the volvo videos, the same way any of us ride big swells. There's not a lot of active trim. Occasionally one or two guys on the grinder ready but no apparent active trimming. At a much smaller scale there's a nice video of Brendan Casey talking through the technique in a Laser. I like the laser videos because everything is over emphasised. Here is Chris Nicholson talking through the technique on for a volvo 65 though. There's not lot of active trimming on any of the volvo videos even though Chris talks about it. It's all helm. It is worth noting th
  23. IMHO the key here is the helmsman is doing a really good job picking a path between wave sets. The concentration is intense.
  24. Incidently, the same thing happens at mach 1. A big energy hump to get over which decreases as flow over more and more bits of your craft go supersonic. A really nice explanation here: https://www.quora.com/Why-is-air-drag-the-strongest-at-about-Mach-1-but-significantly-weaker-beyond-that/answer/Kim-Aaron?ch=10&share=702a0f40&srid=uImx8U Not that you'll ever be getting your melges 24 or cal 40 anywhere near mach 1, but the physics is not dissimilar in that the bow wave is a compression wave that actually starts some distance in front of the bow. You are ostensibly pushing
  25. I shouldn't be so short. But supply enough energy to the order of rho vee squared and anything can exceed "hull speed" without necessarily planing.
×
×
  • Create New...