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      Abbreviated rules   07/28/2017

      Underdawg did an excellent job of explaining the rules.  Here's the simplified version: Don't insinuate Pedo.  Warning and or timeout for a first offense.  PermaFlick for any subsequent offenses Don't out members.  See above for penalties.  Caveat:  if you have ever used your own real name or personal information here on the forums since, like, ever - it doesn't count and you are fair game. If you see spam posts, report it to the mods.  We do not hang out in every thread 24/7 If you see any of the above, report it to the mods by hitting the Report button in the offending post.   We do not take action for foul language, off-subject content, or abusive behavior unless it escalates to persistent stalking.  There may be times that we might warn someone or flick someone for something particularly egregious.  There is no standard, we will know it when we see it.  If you continually report things that do not fall into rules #1 or 2 above, you may very well get a timeout yourself for annoying the Mods with repeated whining.  Use your best judgement. Warnings, timeouts, suspensions and flicks are arbitrary and capricious.  Deal with it.  Welcome to anarchy.   If you are a newbie, there are unwritten rules to adhere to.  They will be explained to you soon enough.  

Doug Lord

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Everything posted by Doug Lord

  1. Sailors Powerboat

    My Dads motorsailer.He started out with a Larchmont "O" boat and then decided to take the family on a cruise. So he found a good deal on this Hand designed motorsailer and had it completely refurbished at Higgins in New Orleans and we took off for Miami, the Isle of Pines, Havana, Nova Scotia and ,finally Brazil......
  2. Foils

    why I waste my time with a complete ass like you beats the hell out of me... I don't -generally- use Froude #'s in design work. I use the old "speed-length ratio"(1.34 X square root of the wl length) or as modified in Vellingas book- 1.5 instead of 1.34 for monohulls. Of course, if for any reason I needed a Froude number I would just multiply the SLR X .30........
  3. Foils

    Dario Valenza along with many others (including me) has been doing much research on foils-particularly for the A Class. This is a segment published Wednesday December 10, 2014: Active foils with mechanical sensors tend to be at a disadvantage in light winds and marginal foiling conditions because there is a drag penalty associated with the control system. In non-foiling conditions the sensors can be disconnected and retracted. But then no lift is available so any puffs would see the passive boat move ahead in foil-assisted mode. Arguably the active setup is also heavier depending on where the sensors are located and how they connect to the foils. So on a small cat the passive foil would have the competitive edge in very light winds. The exact crossover remains a subject of investigation and will be found to depend on variables such as displacement/length ratio, sail area/wetted area ratio and the exact design of the foils... Once foiling the active system requires less deliberate correction by the skipper. This favours the less advanced sailor but probably makes little difference to the nuanced expert who is constantly making adjustments by muscle memory. The crucial difference is this: An active foil can be smaller for a given takeoff speed because lift coefficient can be maximized when needed and dialed out when not required. You can have an aggressively cambered foil on takeoff and a flat low-drag one at high speeds. This is not impossible with passive foils. For example, the section used in the upper portion can have more camber than the one used near the tips. But the compromise is more critical. It is more difficult to have early takeoff and low drag at high speeds.
  4. Foils

    And I was thinking good riddance! Don't let the door hit you in the ass......
  5. Foils

    Latest development of decavitator foils(record setting) : Decavitator rudder foil showing offset.pdf
  6. Foils

    Well, you weren't gone long!! For water: speed in mph X Chord in ft.X 121,000 or for quick reference, table p35 vellinga's book
  7. Foils

    Actually, my foils are based on the work Mark Drela did with Decavitator, foil below. At it's fastest Fire Arrow would be operating at Reynolds numbers very close to Decavitator. The shape of foils is greatly affected by the speed they are intended to work at so foils on a scale model of Super Foiler or of an AC 50 would look a lot different on the model. Since Fire Arrow is a scale model of a 19.5 ft. foiler , the model foils and the fullsize foils would be somewhat different particularly in thickness/chord ratio. Planform would be very similar. As to "footprint" your comment was more nonsense: whether the rudder and board are aft or forward on the foil, as long as both are the same the footprint wouldn't change!- Decavitator foil from Dr. Mark Drela on boatdesign.net 10/27/13 : It is currently in storage at MIT. On 27 October 1991, Mark Drela set the human powered world-record speed with Decavitator of 18.5 knots (21.3 mph; 34.3 km/h) over a 100-meter race course on the Charles River in Boston, Massachusetts. Fire Arrow has done 2 times wind speed in initial testing- about 10mph in a 5mph wind the very first time she foiled. My 56" LOA by 72" F3 did 18mph max reefed in a 22mph wind about 18 years ago and over 2.4 times windspeed in a 5 mph breeze. She had extremely thin foils......
  8. Foils

    Fire Arrow Main and Rudder foils: since the last , most successful test of the boat in July 2014 a lot of study went into the foils including the main and rudder foils. Both the daggerboard and rudder were shortened 6" (1.7' to scale) to reduce wetted surface. The daggerboard was tricky since the foil had to be opened up and the flap pushrod disconnected, then the daggerboard was cut and lengthened. Finally the pushrod was lengthened, the board closed up, sealed and cosmetisized. Then the mainfoil flap was lengthened and small experimental endplates were added to the flap. Note the short and long partial span mainfoil flaps.
  9. Sure. I think it's a cool spelling for a foil based on the name the designers came up with for the foil they invented in 34. Especially considering that so many people don't have a clue what the name of that type of foil is and call it "J", "L", A/V, "V", and more or they just make up something.You can call it UptiP or uptip, but anything else is just bullshit........
  10. Maserati HK to London

    I missed those-thanks!
  11. SuperFoiler Grand Prix 2018

    Good article here: http://www.mysailing.com.au/latest/superstars-stack-super-foilers-on-sydney-harbour
  12. Thats just plain wrong. The UptiP foil invented by TNZ was one of the most significant developments in the history of foils and certainly in the history of the AC. It was responsible for a great deal of "trickle down" with versions of the foil being used on everything from beachcats to 40fters to every large foiling trimaran . The remarkable thing about that foil is it's ability to be designed to maintain flight altitude with no moving parts and generally without regard to speed. I imagine it will be some time before we see innovation again in the AC anywhere near as significant as the uptip foil is.
  13. Crossbow fl 2017

    Crossbow fl 2017--This thing has such great potential that it needs to be mentioned every now and then: Summary of Features and Specifications: ------------------------------- Features: 1) Self-bailing cockpit 2) Boat rightable from 90+ degree knockdown by crew w/o crew movement using the wing regardless of the position of the sliding ballast. a. ballast wing is sealed and has buoyancy much greater than that required to float the ballast sliding inside. b. ballast+ wing can be moved manually or electrically faster than a crew on a trapeze could move. 3) Rig utilizes modified rotating, A Class wing mast, sealed with masthead buoyancy to prevent turtling, 4) Ballast wing pivots: a. to allow trailering b. to move ballast aft when required with wing extension. c. also pivots athwartship to keep weight low to windward and to keep lee side of wing clear of water. 5) Ballast is adjustable in 10lb increments, 6) Boat can be sailed off a beach, 7) Boat features an asymetrical spinnaker, an underdeck spinnaker chute and retractable bow pole, 8) Seating arrangement: (NEW) . a. The skipper will sit relatively low in the boat on a seat that will manually or electrically rotate 180 degrees. This will allow the skipper to steer with his or her aft hand and handle the single sheet and Trapeze Power Ballast System with their forward hand. For Class racing weight equal to the difference between 250lb. and the skippers weight will be carried in a ballast compartment under the seat. 250lb is the maximum crew weight for racing. 9) Large, buoyant "spray rails" act to help provide a dry ride and knockdown recovery, 10) Self-tending jib with variation of Swift solo single sheet system. 11) Boat uses removable, "plug-in" DSS foils for greatly increased power to carry sail with speed. 12) The new changes effectively "turbo" the boat even allowing for windward planing. 13) Boat has an extremely wide crew weight range: approx 100lb to 250lb for normal sailing. All ratios are based on 250lb crew and would drastically improve with lighter crew weight. For class racing, it would be my desire to see a class adopt the maximum crew weight as standard with lighter crew carrying weight under the seat-or perhaps two "weight classes"-whatever it takes to encourage the widest participation. ------------- Specifications: (changes are to be expected) Hull length-15.6' Beam- 4.75' ---at waterline-3.75' Sail Area-(boat will use a carbon A Class wing mast from Matt McDonald/ Falcon Marine LLC, laid up specifically for this boat). --upwind- 161 sq.ft. -- downwind- 290 sq.ft. Weight-sailing weight w/o crew- 223lb which includes: --hull, rig, foils-124lb --Trapeze Power Ballast System: ---wing-21lb. @ 12'-16' length overall, pivots for transport, and moving weight aft. --- max ballast 78lb(8 pieces of lead-removable-.25" X 8" X 12"-about 9.72lb each) Max Crew weight: 250lb-boat is designed as a singlehander. All up sailing weight including crew-473lb DSS Foils: each 1.63 sq.ft.( 6" X 39") 6.5/1 aspect ratio, Welbourn section. Electrical System for moving ballast: Engineered by Rick Willoughby, who did the original "ballast mover" spread sheet. ------- Ratios- see Eric Sponbergs Design Ratio's PDF below ------------- DLR=55.6 --- SA/D= --upwind-42.48 --downwind- 76.78 --- SA/ws- --3.7/1 --3.48/1 including DSS foil --- SCP/Total weight= .3 and .34 if upwind RM from DSS foil is counted. =========== Attached Files:
  14. Maserati HK to London

    Updates from the boat/Team: http://maserati.soldini.it/
  15. SuperFoiler Grand Prix 2018

    Super Foiler- latest video:
  16. Maserati on Foils

    Updates from on-board: http://maserati.soldini.it/
  17. Maserati on Foils

    Maserati in spectacular video: from catsailingnews.com
  18. Maserati HK to London

    Hell no-if the subject is part of the discussion as it was here.
  19. Maserati HK to London

    Translation of Verdiers comments at the end of the video-made relatively shortly before they left Hawaii: "We are here to test the rudders that tends to stall, we have the phenomenon since the boat exists, and so we try to make rudders that are stronger and stiffer, and of course we try to understand why. And it is a complex situation because there is an interference between the main hull rudder and the leeward ama one and so we have made revised drawings for the next season so that the boat can be more controllable and the helm more enjoyable to steer. It is a bit intrinsic to all flying boats as the configurations are quite different for the various flight heights, it would be necessary to change the setting for each condition. If we have more control, we can go faster and it is less dangerous. One of the big works we will do is to make sure the rudder gets up, and that at least when it hits a floating object we do not completely lose the structure of the boat and the control and all that. We will improve anyway."
  20. Maserati HK to London

    This is what the Team said: 13,000 miles, 24,000 kilometres non-stop: this is an uncommonly long route for a 70-foot multihull such as Maserati Multi70. To minimise the risk of damage, instead of sailing in foiling mode the boat will be set up in MOD configuration – although the work to develop the boat’s foiling dagger boards continues with the support of the eminent high-performance yacht designer, Guillaume Verdier.
  21. Maserati on Foils

    Team Maserati: MASERATI MULTI70 SET SAIL TO CONQUER THE RECORD ON THE HONG KONG-LONDON ROUTEJanuary 18, 2018The trimaran Maserati Multi70 left Hong Kong crossing the starting line positioned between the Tai Long Pai and Nga Ying Pal lights, at the exit of the Tathoong canal, at 10: 43′ 23” UTC (18:43 in China, 11:43 in Italy). To beat the record Giovanni Soldini and the crew of the trimaran – Guido Broggi, Oliver Herrera Perez, Alex Pella and Sébastien Audigane – have to complete the course and cross the finish line under the Queen Elizabeth II bridge over the Thames before the 1st of March at 8: 9′ 47” UTC.
  22. Foils

    Fire Arrow Ama foil with wash-in(not wash-out) utilizing iFLAP : This helps the foil work well throughout the speed range especially with low speed takeoff and allows the foil to work, in some respects, like a wand controlled foil but with no moving parts...... See pictures "A" and "B" below that represent two very different load and speed conditions-a perfect illustration of the automatic altitude control of this foil. Furthermore, in light and medium conditions the foils have never needed adjustment after being initially set up.
  23. Artwork by Mike Trim: TNZ Attacks!