superg

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About superg

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    Anarchist
  1. Racing is a highly structured activity; I prefer less structured activities. That doesn't mean I don't enjoy sailing a high performance boat and pushing for better performance. I work very hard to improve my skills while sailing recreationally, and I am probably as passionate about speed, thrills and technique as many racers. I realize that racing would probably up my game, but the structure makes it less fun for me. I would rather test myself by going out when I want, in the challenging conditions of my choosing. By analogy, I free ski on 190 cm race stock giant slalom skis, I can carve a good 40 mph turn on hard snow, but running gates doesn't interest me any more. I get satisfaction from skiing fast for the sensation, the speed thrills and the sense of accomplishment, without being timed through gates. And I get a lot more runs in not waiting at the top of the course. I do sense a tendency among racers to question why anyone would not want to race. Or to suggest that non-racers are poseurs if they sail a high performance boat. That kind of reinforces my preference for "free sailing." Finally (and flame away) there is the culture of competitive alcohol consumption among racing sailors, and I never found sailing (or skiing) any fun when hung over.
  2. Definition of upwind planing is subject to debate. Usual definition is that upwind planing implies VMG > VMG in displacement mode close hauled. Many boats can plane while making upwind VMG (Viper can easily exceed 10 knots at 60 degree TWA but can't match its VMG Going hull speed at 40ish degree TWA. ) Only a few designs (defined by Bethwaite based on sail carrying power) can upwind plane with VMG exceeding displacement VMG. I reckon a sportboat like Viper has SCP in the 0.25 range but that's a guess. Bethwaite mentions FD, 505, Tasar and of course 29er, 49er and other skiffs with sufficient SCP to upwind plane by VMG definition. That said, close reaching at 10 knots plus is too much fun to worry about definitions unless your racing on W/L course.
  3. I attached Weathermeter to the headboard of our Viper 640. I could read the windspeed in iPhone via Bluetooth. Worked pretty well but WM only records average speeds over measured interval. It does not true record second by second data (or iPhone app has no way to see raw data if it is recorded) so I could not use WM to build a polar diagram. Also the Bluetooth connection was intermittent and once it failed, the unit sent no data until the main was dropped and Ghe unit was reset.
  4. What are the most challenging engineering issues of swing keels?
  5. 1003 at full throttle moves my Viper at hull speed 6 knots and will run for hours at 3-4 knots. Typically we only use 10-15% of the battery getting in and out of slip on a typical day.
  6. From specs it looks like a chined Viper.
  7. I'm over 60, and find the Viper 640 to be very manageable solo, great two to three up and comfortable to day sail with four. This is on a 9000' mountain lake with spikey winds. We added a furling jib that can be reverted to class jib in minutes. Solo, I don't furl the jib until 18 knots TWS. Granted, I am depowering big time upwind.
  8. Morning winds typically light from the south-- cool air flowing from surrounding mountain tops north along the Blue River Valley. Wind usually veers to the west by late morning or midday. Buts lots of apparently random shifts and puffs before the prevailing westerlies settle in. Unlike Lake Garda, the prevailing weather comes from the west across the lake, perpendicular to the north-south density flows, and prevailing winds dominate after noon. Dillon's renowned violent storms and microbursts generally come from the W or NW. Watch for rain streams (virga) and plumes of pine pollen and dust, signs of downburst winds. Not a lot of warning of extreme weather so watch Peak One and Buffalo Head closely for signs.
  9. Air density at Dillon (9017') is 0.71X sea level. Force varies by square of wind speed, Dillon lift/drag is equivalent to sea level lift/drag at .84x wind speed. Dillon. Kts Sea level 10 kts 8.4 kts sea level 15 kts. 12.6 kts 20 kts. 16.8 kts 25 kts 21 kts Onset of white caps is 2-3 knots higher wind than at sea level. My boat performs to the sea level polar as close as I can tell, meaning that the lower power from lower air density is offset by decreased air drag.
  10. Hmmm, some folks would likely consider that to be "grossly negligent"... http://keysnews.com/node/36757 The route through jewfish creek. Not 30 knots in.jewfish creek itself.So basically you're either a self aggrandizing sack of shit lawyer, or you were misquoted. Which is it?There are places that are no wake. The rest, 30 knots. Shit for brains.Recent research findings on trolls. Sorry about the poor image quality.
  11. The Seascape 18 would fill an attractive niche in the US if it can be brought in economically. A nice mix of performance and camping-friendly format. Early adopters, please post your reports so this little boat gets some attention!
  12. ^ recycled video from previous page. Nothing new to show?
  13. I singlehand my Viper to 12-15 TWS in two-sail mode. Over that, I furl the jib. Mauri Sails jib with luff wire; Ronstan series 60 furler; reversible to class jib in minutes. The Viper is very comfortable for four-up daysailing with two non-sailors.
  14. To quote what I posted previously,"VPP studies suggested that a heavier crew weight than GP26 class rule would be generally faster around a W/L track in 15 knots and above." Essentially the GP26 4 person crew weight is too light for optimum performace in over 15 knots. 5 is better. As the wind strength increases, and you need to sail upwind, extra crew will make the boat faster upwind. A Gp 26 will be less over-powered with a short-handed crew of 3 than similar "powered up" sportsboats; the boat has a heavy bulb on a deep fin, and my design has a very stable hull form. Would it be easy to sail a GP26 with 3 people in 15 knots or more? A crew that small will need to be very, very good to set/gybe/take-down the spinnaker. Jim, I will be looking forward to your 6m design, which sounds like it will better fit my needs (smaller crews, more stability than the current 20s)