Spoonie

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Everything posted by Spoonie

  1. Spoonie

    don't mock me

    Mmmm... is that cardboard? the front is definitely going to fall off that one
  2. Spoonie

    ticky tack?

    frankly, y’all should learn to float a kite. human poles in a takedown? luxury...
  3. My parents are cleaning out, but in their position was a book of mine I specifically asked them to keep: "Catamaran Sailing To Win", Chris Wilson & Max Press , 1973 Which you can amazingly still get on Amazon https://www.amazon.com/Catamaran-Sailing-Wilson-Chris-Press/dp/B002I7IKCI There was a bunch of reasons I wanted to keep it, but one of it was the notes around the design and campaign of "Miss Nylex", I think one of the first, if not the first solid wing C class. It was also apparently quite controversial in the use of "Nylex", it's sponsor, as part of its name. Anyway, very much old hat now, but I thought some of you might find of interest the short note and drawings by wing designer, Roy Martin on the benefits of rigid wings (circa 1971). The justification for one of the first wings in Catamaran racing we now know and love in the Americas Cup. Cheers Spoon. MissNylexWing1.PDF MissNylexWing2.pdf MissNylexWing3.PDF
  4. Spoonie

    Showtime capsize on return trip

    My wife thinks this is a forum about Sailing
  5. Spoonie

    I'd like to thank the previous owner for...

    Someone in my previous owner history used metal tacks to attach the figure 8 wire to the bulkheads. apparently didn't get perfectly centre in a few places.
  6. Spoonie

    Showtime capsize on return trip

    I don't know where you go it, but I posted it in reply to you up above. It's not a proper keel test. They're attempting to validate design assumptions on acceleration and forces, as opposed to confirming the failure mode of the as built design meets expectations. One of those boats in that paper would go on to have a catastrophic ram failure though. A good example of a proper test would be the work that went into the de Havilland Comet https://en.wikipedia.org/wiki/De_Havilland_Comet I would suggest such a test is cost prohibitive in most yacht design scenarios.
  7. In the old days, the North MK I was a softer cloth and routinely a flatter head than the hyde MK I. From my experience, there was also about a .4kg difference between light and heavy top sections at the dealer (2.2kg to 2.6kg from memory). I think the Aussie top sections seemed like a harder temper though. I also felt the aussie bottom sections were stiffer as well. Maybe psycho sematic. We did weigh a lot of top sections though. I haven't sailed with a MKII sail or carbon section. If the carbon sections are at least consistent from batch to batch, that has to be a good thing! Edit: looking at other top section weights, maybe my memory was a little off. I certainly remember 2.6kg. I had it in my head that the other was 2.2, but that seems a long way from other weights listed online.
  8. Spoonie

    Showtime capsize on return trip

    Nah... as an applied mathematician, it's a guesstimation. you build a model, plop in some boundary assumptions & conditions, and spit out some numbers. Your model could be wrong, your assumptions could be wrong, or both. Chances are you're wrong somewhere. They're certainly called assumptions for a good reason. Newtonian physics being what it is, they could be highly educated guesses, but they're still just an approximation of the real thing. Especially when you add hydrodynamic loading into that picture. You can see from the paper I posted above, the numbers used were relatively arbitrary. 1G loadings with a safety factor of 3 using "quasi-static analysis". In testing, Hugo Boss bumped up against those numbers from time to time. WOXI was a little more comfortable inside the comfort factor, but definitely over the 1G spec. 1g and 3x are too convenient for me. IMHO someone's made an educated guess. Maybe there was some real data that informed those numbers who knows. In some circles though, breaching the comfort factor would be considered an engineering failure. Either way, as fastyacht pointed out, race boats are experimental engineering. There's precisely one of them (in many cases) built to withstand at a bare minimum, the structural needs to get them around whatever race course they're on. With all due respect to the NA's here, to suggest they have a perfect understanding of the dynamic loads placed on those boats, I think would be giving them a lot of credit. Especially the big fancy ones (Boats, not NA's) *shrug*
  9. Spoonie

    Showtime capsize on return trip

    No such structure exists. Everything has a failure mode. One of the practices in building resilient systems is to assume the element has failed and then assess the impacts across the rest of the system. All too often people try to guess why it might fail. If they can't, they assume the risk to be minimal. this can lead to solution designs that are inherently less resilient to failure than other options. Even experienced engineers are not immune to this and there are many famous examples (like the challenger disaster) where an assumed low risk proved to be vastly inaccurate. I know little or nothing about keel design, but back of the envelope, even a forged keel will have failure points. The bolts, the hull structure, the right angle flange at the top of the fin, thinner material mid span to the bulb. Lots of opportunity for failure, but perhaps more reserved capacity for failure in the system. There was also a presentation at the Institute of engineers (I think) a few years back. One of the big boat programs here put a load cell on their keel and I think were genuinely surprised by the extremes of the dynamic loadings. That led them to update their keel maintenance & inspection program but I think was still within design parameters. I seem to remember a paper on it, (maybe this one?) but I can't be arsed looking for it too hard. That paper above though suggests the loadings were as high as the "ultimate loading" they thought the keel would endure, but also that the nature of those loadings was pretty specific to each boats design. I guess that leads to one of the earlier assertions about guesstimating the loads. At any rate, I guess that's a long way of saying in any dynamic critical system, you're always better off assuming a component might fail, and acting accordingly than the opposite
  10. Spoonie

    Cancelling a Race for High Winds: No limits in SI's

    Crazy Ivan.... when i was mountain biking lots I went riding with a mate. We were elbow to elbow down this trail drifting through corners with shear drop offs on the outside. It was fun because we trusted eachother’s capability implicitly. I have the same implicit trust (and distrust) of my fellow skippers. some I outright avoid, others I have no quams about being gunwhale to gunwhale with knowing that should something go pear shaped, the other would respond. I’ve come to expect even great sailors have the odd crazy ivan. It’s how you both react when you are close that makes difference between fast, fun, and safe. As to abandonment, as Fast said, devil is in the details. I would have thought that was a bit soft, especially because it was closed flat waters, but maybe Im missing something. I certainly agree documenting wind speeds makes things more complicated. unfortunantely here, racing will be cancelled on strom and gale force warnings regardless of conditions. that’s a liability issue. On the flipside, i’ve had arguments with RO’s who refused to abandon despite active lightening storms on course. The RO had the idea that lightening would go aound the boat, and besides, his kid was winning. That day on another course a laser was struck, exploded, and the sailor found himself in hospital for a week. on our course another boat returned to shore after apparently experiencing an electric shock holding on to the stay. That club developed an explicit storm risk policy after that as part of their risk mitigation plan, providing clear guidance to RO’s introducing greater consensus and the ability for the executive team to overrule the RO on such things if it was deemed appropriate to do so. it was a policy document though, not an SI.
  11. Spoonie

    Australian Sailing

    QYA has had interesting things going on as far back as the late 90's.
  12. Spoonie

    wtf Australia what is yall doing??

    well on the bright side, it should provide some phd candidate with a nice little bit of research on global wind patterns.
  13. Spoonie

    wtf Australia what is yall doing??

    i have a maths degree (dynamic systems mostly). I’d say the maths component of that was pretty tough. just say’n
  14. Spoonie

    Non-furler headsail handling options

    Outside gybe with a 2m strop between your sheets and the chutes clew. The strop acts a bit like a delay fuse when you madly pull the sheets through. For me, the problem is dropping the lazy sheet in front of the bow. You need to somehow keep the sheets tight while letting the kite blow forward. Hence the strop.
  15. Spoonie

    Non-furler headsail handling options

    This. I now have two jibs and a storm jib. the #2 has two sets of cringles and a big zipper along the bottom. I've never actually used it as a #3 because most club racing gets called off before it's windy enough, and I'd spill my drink if it was that windy out for fun. That's beside the point. I'm comfortable knowing that if it ever does reach 30-35's I can reef the #2 without a headsail change. Top investment so far Putting hanks on, If you run a thin line up and back from the head when you hoist, you can also pull the jib down and hold it down without leaving the cockpit. Sheet on, pull jib down, will stay reasonably manageable flaked on the bow Put a bit of bunjy cord between your pull pit so the bottom hank doesn't twist on the forestay turnbuckle
  16. Spoonie

    talk to me about the tartan 30

    "oh my, I have a thing for 30'ers... just look at her form, her curves, with that integrated keel? And what I would do to have an aft bustle like that. Could you imagine what we could do in that cabin?" ...or is that not what you meant?
  17. Spoonie

    Best 2-up beercan racer

    I had a custom rope bag made up for the front of the cockpit with bottle holders. Otherwise get yourself some of these: https://decathlon.com.au/products/168751# Beer goes in bag, tack/gybe, beer comes out. I'm considering gymbles
  18. Trust me, I'm a consultant. I'm never wrong
  19. I note that the instruction says "fitted" not "permanently installed". The wording is very specific. The SR use the terms "fitted" "securely fitted" "fastened" "securely fastened" "Permanently installed" presumably, very specifically. Of course the SR's also say the VHF for 5 is recommended to be permanently installed (not fitted). But the SI's "Amend" that rule. To my interpretation, for what that's worth, a hand hold tethered into a bracket is "fitted" to the boat. Get the right safety guy and you'll get sign off. As to the protests, you can always appeal. Very clear appeal path from club level upwards. You might win on any one of the 5 interpretations that have been posted on the same concept. They might just write clearer instructions in response. Probably a win win either way. How much do you like going sailing? a simple vhf, removable aerial, small portable battery, and wiring will set you back about $500 and about 5kg's. Our club has made VHF's compulsory for Cat 7 after an incident last year. *shrug*
  20. Spoonie

    Sun Fast 3300

    Time to spend some more time in dinghy's shaggy
  21. Spoonie

    Why skippers fail in PHRF, it's not the boat

    With all due respect, perhaps he should, but I definitely don't agree with the majority of your advice. I'm sorry, I don't normally down vote, but I had to, to counter the sea of approvals. Whether it's OD or Handicap, make no mistake it's your performance against the rest of the fleet that matters. It's time against the clock *and* the fleet. You really can't ignore that. With that in mind, Shenanigans that screw you over in handicap races screw you over in OD racing and vice versa. Things that allow you to win in handicap racing, allow you to win in OD and versa. Around the cans, the most important move you will make in any race (OD or handicap), is to be on the correct side of the first shift relative to the fleet, with clear air and ability to tack. It is the one and only time you have leverage over the whole fleet. From then on, it's all about making sure you are in the right position, relative to the fleet, to take advantage of the next shift. You are always trying to be between the fleet, the next shift, and the next mark. If you're on your own, it's just about the next shift and the next mark. Certainly starting on port tack, then checking in 5 mins later to see where the fleet is a sure way to be wrong probably 50% of the time at the one time you could be putting significant time (real or virtual) into the whole fleet. Also, if the fleet is diverse, then there's a high probability that at least some of them are sailing in very different breeze to you regardless. Sailing your boat to its maximum performance speed wise is the barrier to entry to the podium in any race, but it's only 1/3rd of the picture. With the right leverage, a slow boat that is in phase will beat a faster boat that's out of phase nearly every time. Why is this relative to the fleet bit important? because sailing is a game of risk. Whether OD or handicap, the boat that plays that game the best *compared to the rest of the fleet* generally wins. So that sometimes mean forgoing what may be a more optimal course, because it's only optimal if you're right. Speed, Strength, Smarts: The golden triangle. Speed, You have to be get the maximum potential speed out of your boat (with some exceptions) at all times. Strength, you need to have more capability (boat handling, endurance, etc...) than the next guy. Smarts, your strategy and tactics need to be better than the next guy. If you lack any one of those 3, then you need a double handling of the other two. For what it's worth, here are my tips: 1) We've established speed is a given. Faster boats always have the advantage. It sucks being a slower boat in a handicap fleet because all things being equal, they will be 2nd to the shifts and rolled on downwind legs. The closer boats are in handicap and speed, the fairer the results will likely be. In an OD fleet a lack of speed is death 2) Always know where the fleet is, and I mean always. You need to know how you're doing in your own little patch, and relative to your own fleet. going fast in the wrong direction compared to everyone else is not fast. Waiting for 5 mins is death. at 6 knots, 5 mins in the wrong direction will put you 100m behind in 5 deg shift. 33sec lost right there. more than Double that in a 10 deg shift. Do that off the start and get a 10deg shift against you, you will have just lost 1min against *the whole fleet*. It doesn't matter if it's handicap or OD, you need to do a lot to make that up. 3) Always know where you're going with respect to the next mark. See above. That mostly means being to the left of the mark when the breeze is going left, and to the right when the breeze is going right. It also keeps you in check w.r.t the fleet. The fleet will mostly just follow who they *think* is right. Not who actually is. 4) clean air and room to move as you need to wins races. Sometimes you need to sacrifice either speed, or opportunity to maintain that. There's no point getting getting the most out of a shift or whatever to be stuck with someone on your hip. Balance that risk (shenanigans vs, opportunity) and think ahead. 5) To perhaps clarify an earlier comment from someone, team work is key. The best crew is the one that works together well. they have a secret language and things magically happen without much discussion. They don't need to be rockstars to do that, just good team people. The best skippers don't bark orders, they give their team room to execute and learn. 6) practice. All truisms regardless of OD or handicap. In short, I first heard this idea that Handicap racing was somehow different last year. I was taken by surprise frankly, because I really struggle to see any difference. Control what you can control, which is your position between the fleet and the next mark. Ignore the rest, never take the foot off the gas. *shrug*
  22. Spoonie

    boy is this girl in for a surprise..

    I’m not sure that’s true. Virtual conferences in various fields do exist. But IMHO, they suck... if you really want to meet and exchange ideas, it is very hard to beat a face to face conversation.
  23. Spoonie

    boy is this girl in for a surprise..

    For sure, but it’s like any of the carbon based industries. Either a transition to carbon neutrality is needed, or a orderly exit of the industry ala Germany’s shutdown of the coal industry. I suspect it will be a long time before air travel is displaced by technology in business. Face to face conversation is still the best form of communication in many settings. Ethical organisations though is becoming a thing and certainly limiting travel may be part of that. I would suggest leisure travel is more an indication of economic circumstances than the price of the flight. Eg the Aus dollar makes it twice as expensive to say travel to the states or Europe than it did 10 years ago.
  24. In short, a lot. There a lot of standing jokes about it. How do you pick a dentist in the bunch, how do you pick the masters riders on the track etc... etc... a bike shop that supported me for a long time would always keep one $20k bike in the floor. They helped inflate overall sales and they would always sell a couple a year.