Crossbow fl

Discussion in 'Sailboats' started by Doug Lord, Jun 21, 2012.

  1. Doug Lord
    Joined: May 2009
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    Doug Lord Flight Ready

    UPDATED SUMMARY: 8/9/14
    ================================
    This is a detailed summary of the boat and its systems-some of it posted before. Funding will be sought and looks possible right now. I believe that this technology can open up a whole new world of singlehanded performance monohull sailing to people who might otherwise never get to experience a planing reach with an asy flying! There is nothing like it anywhere and it would pioneer a whole new way to sail a fast monohull dinghy.
    IMPORTANT: the decision has been made to go with the powered up version of the Crossbow fl . The rotating seat(along with the Trapeze Power Ballast System) is the key to making the powered up version work and I'm now convinced that "we" can make it work-and work well.


    ==================
    Crossbow fl

    Part 1--The key to this boat is the Trapeze Power Ballast System wing. The wing is sealed and allows ballast to slide side to side as the wing slides. The cg of the ballast(80lb) moves nominally 13' (slightly less in practice-about 12.5' in 3 seconds/ 4.17 feet per second/2.84mph) from the center line of the boat. Same weight movement as if the wing was 24' long! Trapeze wires support the wing and a carbon "apparatus" holds the wing at the center of the boat. This apparatus allows the wing to pivot around a vertical axis, and a fore an aft axis parallel to the centerline. Weight is adjustable in 9lb increments. Everything is adjustable including the speed of wing+ballast movement. The system will be electric with battery capacity enough for rapid and frequent movement of the ballast + wing over two 8 hour days w/o recharging. Capacity can be increased in special cases. Movement is controlled precisely by the crew using a joystick.
    ---
    Part 2- Another key to the boat is the buoyancy of the sealed wing and its wing tips which far exceeds the buoyancy required to float the ballast. That means the wing can be used to create righting moment( due to its buoyancy and not the ballast) in a knock down, righting the boat.
    ---
    Part 3- The prototype will test DSS foils which have worked very well -especially in the Quant 28 Sportboat(unparalleled race record) and in the Infinity 36. The foils will be used in an entirely new way -they will plug in rather than operate from a trunk in the boat. The other applications of DSS work in a trunk that allows the board to retract or partially retract. The new Quant 30 uses unique curved DSS foils that can be independently retracted and/or deployed. The Crossbow system allows the foils to be inserted and locked in individual trunks. The boat is designed to facilitate this by sailing at a 10 degree angle of heel keeping the windward foil clear of the water and reducing hull wetted surface. These foils appear to offer modest RM upwind and nothing short of tremendous RM off the wind. In a boat like this, the combination of DSS foils and the Trapeze Wing movable ballast system, offer lots of power to carry sail and planing performance with an extremely wide crew weight range. For DSS to be most effective, the hull must be designed specifically for it to allow the foils to be in the proper position when exiting the hull. The foils must be at least 1 chord below the surface at a 10 degree angle of heel.
    ---
    Part 4- One of the most important phases of the development of this concept and the refining of the Crossbow fl prototype design is complete-model testing. For over 10 years the concept of the Trapeze Power Ballast System has been extensively tested on numerous RC models as well as a few non-RC models. The results are conclusive: the system works and a prototype has an excellent chance of success.
    In different places in this forum an ongoing, uninformed minority lash out at model testing which is too bad. Julian Bethwaite, among many other's, has remarked that model testing saves time and money. Alain Thebault(Hydroptere), Dr. Sam Bradfield(Skat, Rave , Osprey and more), Greg Ketterman(Hobie Trifoiler and Longshot), Bill Burns(CBTFco), Hugh Welbourn(Dynamic Stability Systems), Yves Parlier(Mediatis Region Aquitaine ),Bernard Smith(40 knot sailboat), Paul Larsen(Sail Rocket) and many others have used RC model testing to test basic concepts and refine the design prior to building a full size prototype. It is one of the best ways to test-particularly so in regard to the Trapwing System. Testing involved the function of the Trapeze Power Ballast System and not the electrical system.
    Testing the movable ballast system is one of the areas of RC model testing where the results can be 100% trusted and where the potential of the Trapeze Power Ballast System has been thoroughly tested. One difference in the model testing of the system is that the skipper has to have faster reactions than are required on the full size boat, since, as the system is scaled up reaction of the boat and the ballast take longer to happen. That means that the skipper of the RC boat has to have quicker reactions and more "anticipation" than the full size sailor on Crossbow-and also means that sailing a Trapeze Power Ballast System model is excellent preparation for sailing the full size boat.
    ---
    Part 5- The Rotating Seat- this is a system that will allow the skipper to sit facing the opposite side instead of facing forward like most small singlehanded keelboats do-and to be able to switch sides while remaining seated. I personally prefer to sail with the hiking stik in my aft hand and the sheet in my forward hand. On this boat the wing control/joystick will most probably be handled by the forward hand as well UNLESS there is a way to do it by using a twist grip on the extenstion tiller-but thats a ways off if it happens at all. The biggest advantage of the Rotating Seat is the fact that it increases the RM generated by the crew 4 times over what was possible with the fixed single or tilting seat both of which faced forward.The seat will be set up to be able to be moved manually or electrically.
    ---
    Part 6-The Development Team: (from post #1)

    - I retained the services of Eric Sponberg to help spot glaring errors and to help with engineering.
    - I retained Rick Loheed to build the DSS "plug-in" foils.
    - I'll use Falcon Marine, LLC to "carbonate" the hull and to provide a portion of an A Class Catamaran mast for the Crossbow(laid up for this boat out of his brand new mold). Matt McDonald does some of the finest work I've ever seen on the cats he builds.
    - I've retained Sharon Dixon of Rockledge Architectural to actually carve the hull of this boat from a couple of solid blocks of Styrofoam. The "boxiness" of the shape reflects her capabilities-no compound curves-etc. Using this method and having Matt carbonate it saves above $1500 over having the boat built out of wood. UPDATE: Wood may play a greater role than originally intended but Sharons styro capabilities will still be vital for the large rub rail.
    - I've received a great deal of help from Hugh Welbourn in deciding on the foil section , placement of the foil , angle of incidence and other matters relevant to designing for a DSS system. This boat will use "plug-in" DSS foils that will be installed on the beach(or not) depending on conditions. Testing will be facilitated by simply leaving one foil off.
    - I'll use Rick Willoughby for design of the electrical system. Between Eric, myself and Rick we will choose a supplier in the states for the parts required for a first class, reliable Power Ballast System.

    ======

    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.
    ===========

    Pictures-L to R- 1) sailplan of original and updated Crossbow fl, 2) model of Crossbow fl with DSS foils, 3) same as #2 except shows the Trapeze Power Ballast System wing, 4) Super Scow using Trapeze Power Ballast System, 5) & 6) Melges 24RC using Trapeze Power Ballast System, 7) the completed DSS foils for the fullsize boat, 8) Crossbow fl sail insignia:
     

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  2. Doug Lord
    Joined: May 2009
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    Location: Cocoa, Florida

    Doug Lord Flight Ready

    Inspirational disabled sailors:
    Picture from Scuttlebutt-Billy Floyd, a double amputee, sailing his catamaran on Lake Mohave in Nevada. Floyd lost his legs in a hang gliding accident, but it hasn’t slowed him down. Photo by Tracy Huff. - See more at: http://www.sailingscuttlebutt.com/2...mputee-trapeze/#sthash.B2VESZR2.nzDNcRpo.dpuf
    ------
    Another example of courage and ingenuity: http://www.theguardian.com/society/2009/aug/31/hilary-lister-solo-voyage-britain
    Picture-Paralysed from the neck down, Hilary Lister used advanced technology allowing her to steer and control the sails by sucking and blowing through plastic straws. She completed a solo voyage around Britain! Photograph: Mark Lloyd/PA
    ------
    It's time for a boat like the Crossbow fl.....


    click-
     

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  3. Doug Lord
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    Doug Lord Flight Ready

    I'm going to finish the concept model of the Crossbow fl, pictures of which are in this thread. It needs to be painted and have the rig completed.
    There is a possibility that I might do a performance RC model using the Trapeze Power Ballast System since I don't have any of the RC models shown on this page anymore. The model would be used for videos illustrating the concept.

    NOTE: in post 241 I mentioned Eric Sponbergs paper on design ratio's but failed to include it there-here it is:
     

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    Last edited: Aug 21, 2014
  4. Doug Lord
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    Doug Lord Flight Ready

    I'm working hard on trying to find a way to get this proto done. I'm considering a crowd funding system like Kickstarter or one of the others. Also, going to have an rc cat using the Trapeze Power Ballast System fairly soon and am considering making a nearly exact scale sailing RC model of the Crossbow fl so that people can get an idea of whats involved in handling the system. I've shown several of the original models using the ballast system in this thread but I don't have any of those anymore. So,in addition to the D4Z(cat) system, a scale sailing version of the Crossbow illustrating the concept of the wing having more buoyancy than it takes to float the lead inside(or on it) may be a handy "tool" to have around and would produce some very cool videos. The model could have a working asy spin but that's very expensive -close to $6-800 to put it together so I'm leaning against it.
     
  5. Doug Lord
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    Doug Lord Flight Ready

    Crossbow fl--model

    IF I decide to go ahead with a nearly scale RC sailing model of the Crossbow fl, these are the dimensions:
    LOA-5'
    --
    Beam-1.5'
    --
    Scale weight*-18lb
    --
    Scale SA*-16.75 sq.ft(2412 sq.in)
    --
    Scale Trapeze Power Ballast System weight*=3.32lb

    * These values will change.
     
  6. Skyak
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    Skyak Senior Member

    Doug,
    I have given you some tough advice on this subject in the past. It appears now you have decided to go for it so I will focus on helping you have a successful campaign.

    There are two major crowd funding sights, Kick starter and Indigogo. For this project I think Indigogo might be better because;
    -it is more oriented toward 'giving to a cause' where kickstarter is more toward creating more mainstream commercial companies.
    -Indigogo is not an all-or-nothing funding sight like KS.

    A good video is very important but it will also pay to have some project logo products as rewards. You should have a webb site for communications and you can give mention to donations. Apparel is good -a nice shirt with project logo will be prized as a conversation starter for the cool project they funded. And it might be a bit of work but if you offered a working model of the concept I think you might attract some big bucks. You have the modeling talent, offer it. An alternative would be invitation to participate in some project event -sail the RC or full scale model for example.

    Lastly, you need a clear plan of what will get funded and when it will be produced. This is where you can talk up what you have already done and also the value you are creating for subsequent 'users'. You should be clear -is this 'open source' or is it intended for a specific nonprofit but not everyone.

    I have not seen any crowd-funding projects on this site, only proposals. I think it could be a great tool to move ideas to boats. Maybe we need a thread dedicated to crowd-funding in the 'all things boats' blog.
     
  7. Doug Lord
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    Doug Lord Flight Ready

    Thanks Skyak. I'll decide shortly on whether or not to do a model. It's probably a good idea especially since it will facilitate videos. It will be tough to do(financially) but possible after the cat project is finished(built)-then I will have two complete boats to do testing with-D4Z cat and the Fire Arrow tri. The Crossbow model won't be for testing -just for demonstrating in videos. Ideally, a full size proto would be where to start and use the funding to refine the concept and fund tooling and/or a "production prototype". But it will be difficult to raise any money without some sort of physical "proof of concept"-like a working model.
     
  8. Doug Lord
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    Doug Lord Flight Ready

    Crossbow fl--model

    There are problems in scaling the Crossbow fl down because of the loss in righting moment which means the Trapeze Power Ballast System has to carry
    more lead. That means that the scale buoyancy of the wing won't be enough to float the lead and right the boat as it will in the fullsize version. I may be able to tweak it so the model will work -we'll see.
     
  9. Skyak
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    Skyak Senior Member

    IMO, if you are doing crowd funding I think you should just go for a full scale proto. It cost far more but the result is proof of concept which is a more attractive milestone. It also opens the opportunity to put butts in boats which is the best thing you can do for the concept. I covered this before but if this is to be powered you should do a 'mule' proto -dry land rig showing performance in controlled conditions. If you are using Indigogo you can have milestones that contribution levels cover.

    You have already built RC models and can just video those. If someone wants a scale model just make it a 'reward' ex donate $XXXX and receive a scale model.
     
  10. Doug Lord
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    Doug Lord Flight Ready

    Crossbow fl--model

    Don't have any of the original models shown in this thread but I'll have a cat using the Trapeze Power Ballast System shortly. I definitely won't do a model if
    I find I can't tweak the design enough so that the model works exactly like the fullsize boat will. My preference would be to do a full size proto as well. I've already gone over it with Matt and Eric. The problem is money but that could change.
     
  11. Skyak
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    Skyak Senior Member

    I seem to have lost track of this project. I have been away a while. I thought this was a DSS monohull with shifting ballast above the waterline and a fairly stationary crew. What happened to the model?

    The power ballast would have far less 'gee wiz' value on a catamaran that has more of it's own stability from buoyancy and it does not self right after capsize. I still think that the power ballast on any sailing kayak would be more demonstrative.

    The opinion above is only about what a crowd funding campaign would look like to potential contributors, nothing else. Have there been major changes to the concept? If so could you direct me to the most pertinent post numbers for status?
     
  12. Doug Lord
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    Doug Lord Flight Ready

    The RC models of the Melges 24 RC, Super Scow, microMoth all using the Trapeze Power Ballast System were either sold or recycled. I still have the small concept model. The D4Z model will only demonstrate that the system works on a foiling cat that is extremely powered up-nothing else.
    Ideally a full size proto needs to be built or if that's impossible then an RC scale version that works exactly like the fullsize version needs to be built. The concept of using the wing to right the boat as well as illustrating handling in various conditions would be possible with an RC model IF I can solve the scaling issues satisfactorily. And that may be possible with a very large model-at least 5'LOA(about 1/3rd the size of the fullsize boat)
     

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  13. Doug Lord
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    Doug Lord Flight Ready

    Crossbow fl concept

    This is a rehash of an earlier version of the Crossbow FL concept 18' LOA with much more power and therefore more expense to develop. But I really like the looks though it would be very wet unless it foiled. It's a direction this concept could move in down the line. The original concept of the foils was for foil assist not full flying and was before I knew about DSS.
     

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  14. Doug Lord
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    Doug Lord Flight Ready

    It looks like I can make a model work exactly like the full size boat will work
    and it may be the only avenue open to put this together.
    I'm convinced that the concept offers a fun, fast, safe way to sail and that it needs to go forward. I think that whether a person has a disability or not the opportunity to sail planing dinghy is one of the great thrills on the water and this boat can open that experience to a lot more people.
     

  15. Doug Lord
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    Doug Lord Flight Ready

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