High Performance MPX Foil/Self-righting Trimaran-The Test Model

Discussion in 'Multihulls' started by Doug Lord, Dec 28, 2010.

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

    WOLF---daughter of fire arrow / Concept Model

    The curved piece has been modified in order to lower the ama hull(stage 1 of the two stage ama) while maintaining high dihedral crossarms.


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

    WOLF---daughter of fire arrow / Concept Model / Bottoms Up!

    Another way of looking at the boat:

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

    Doug Lord Flight Ready

    WOLF---daughter of fire arrow

    Updated 3/25/17 specs and notes:
    NOTE: I'm sure various changes will continue until(and after) the boat is launched-that's what development is all about.

    WOLF Specifications


    LOA 15.458' (4.7m)
    ---
    Beam max-18.75' (5.72m)changed 3/22/17
    -beam folded-8' (2.4m)
    -main hull beam on deck: 2.625'(.8m)
    -main hull beam at wl: 2.125'(.65m)
    -main hull L/B at wl:7.27/1 (planing)
    ---
    Two Stage Ama-11.5' (3.5m) changed 3/22/17
    -ama hull-7.7' (2.35m)
    -ama hull beam .58' (.18m)
    -ama hull L/B=13.3/1 (planing)
    - curved piece-5.9' (1.8m) changed 3/22/17
    - overlap- 2' (.61m)
    - two stage ama canted bottom out 12 degrees.
    - two stage ama buoyancy(not including crossarms)=252lb(61%)
    -added 3/25/17 : Note: planing two stage ama is designed for incidental contact with the water. Not to be sailed "on" on a regular basis since foils provide vertical lift. The planing surface is used to reduce drag when the ama does make incidental water/wave contact at speed.
    ---
    Weight:
    -boat-210lb (95.45kg)changed 3/22/17
    -crew-215lb (97.7kg)
    -sailing/flying weight: 425lb. (193.18kg.)changed 3/22/17
    ---
    Sail Area:
    -main + jib= 165sq.ft(15.34sq.m)changed 3/22/17
    - spin/screecher about 150 sq.ft(13.9sq.m)
    -pounds per sq.ft./SA:
    --upwind=2.58 changed 3/22/17
    --downwind=1.35 changed 3/22/17
    ---
    Designed flight angle of heel: 5.5 degrees to 15 degrees. Standard 10 degrees.
    ---
    Main hull flight altitude at centerline: .5'(.15m)---2'(.61m),Standard 1.19'(.36m)
    ---
    Righting moment:
    -crew 215 @11'= 2365ft.lb.(3206.5 N/m)*
    -boat 200 @ 7.5'=1500ft.lb.(2033.7 N/m)
    TOTAL RM= 3865ft.lb (5240.2 N/m)
    Downforce from main foil(if used) approx. 1500ft.lb.(2033.7 N/m)
    * N/m conversion done from online converter
    ---
    Foils:
    -uptip foil in each ama, adjustable AOI and up/down(mostly retractable). Tentative AOI-3-5 degrees over twisted foil. Asymmetrical section.-- added 3/25/17
    -mainfoil wand altitude control, adjustable AOI(nominal 2.5 degrees),up/down(mostly retractable). Symmetrical section.-- added 3/25/17
    -rudder T-foil, adjustable AOI(nominal zero degrees),retractable.
    -Note that in their smooth water configuration, the uptip foils can be left down at their flying position when the boat is pulled up on the beach! And, of course, as mentioned before these foils do not have to be raised or lowered each time the boat tacks or gybes. This is not found on any other boat using uptip foils.
    The Fire Arrow Type/ WOLF uptip foils are shallow draft compared to most other types of hydrofoil. added 3/29/17
    ---
    Planing surface on lee ama hull is designed to be flat when main hull is just clear of the water(6") and that will occur at an angle of heel of 12 degrees.(Depending on foil lift-3/25/17)
     
    Last edited: Mar 29, 2017
  4. Doug Lord
    Joined: May 2009
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    Doug Lord Flight Ready

    Fire Arrow Test Model/ Maserati/ M24 Test Model/WOLF-daughter of fire arrow

    It just dawned on me how interesting this comparison really is. The M24 is a heavily modified Diam 24 trimaran that is being used as a Test Model for the new 100' Macif. It is being used to test foil configurations, primarily. As far as I know the M24 has not tested a hydrofoil on the daggerboard like Fire Arrow, Maserati and WOLF. However, it does use Uptip foils on the amas because of their ability ,coupled with a rudder T-foil, to automatically control ama altitude. Fire Arrow was the first trimaran foiler of any size to use Uptip ama foils.......
    The 5.5' Fire Arrow was originally an exact scale model of a 19.5 sport tri but when the decision was made to build the WOLF at 15.5' the Fire Arrow became the "technical" test model for that boat and has tested the basic three point foil system, oversquare platform configuration, Two Stage Ama and planing ama and main hulls. The limited testing of the Fire Arrow proved that the foil system worked 100%-more model testing may be done. From a testing standpoint for the Fire Arrow/ WOLF development, one of the most significant milestones has been the successful testing in over 6000 ocean miles of the basic Fire Arrow Foil System by the modified full foiling MOD 70 Maserati. The main elements of the Fire Arrow Foil System tested by Maserati are the three point foiling configuration based on an ama foil that works like an Uptip foil to give automatic altitude control to the ama, the rudder T-foil and the "Manta" foil on the daggerboard which is an adjustable AOI hydrofoil capable of lifting the whole boat as does the daggerboard foil on the Fire Arrow (and WOLF). The Maserati use of the basic Fire Arrow Foil System(independently designed and developed by Guillaume Verdier) proved beyond a shadow of a doubt the value of the Fire Arrow Foil System that I designed and developed over the last 7 years. Now I hope to take this development one step further through the design and development of the 15.5' WOLF.

    M24 Test Model:

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    Fire Arrow Test Model:

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    Maserati Using the Basic Fire Arrow Foil System:

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    Last edited: Mar 30, 2017
  5. Doug Lord
    Joined: May 2009
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    Location: Cocoa, Florida

    Doug Lord Flight Ready

    WOLF---daughter of fire arrow / Concept Model

    These are basically where the main seats will go. They will have 3" to 4" cushions. Keep in mind that there is a lot more detail to finish off the installation. There will actually be two levels of seating in case the skipper needs more RM to get started. Thought about making the main seats slide but that was a bad idea.
    Extreme comfort is a major requirement of this boat.


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

    Doug Lord Flight Ready

    WOLF---daughter of fire arrow / dihedral test

    Just tested the model set up to simulate the mainhull floating at static with the boat heeled so that the inboard edge of the ama planing surface was just touching the water. The resulting angle of heel was 8 degrees which is excellent! So dihedral is final for now.....
     
  7. Doug Lord
    Joined: May 2009
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    Location: Cocoa, Florida

    Doug Lord Flight Ready

    WOLF---daughter of fire arrow

    Finished carbonating of the underside of the curved pieces and crossarms to lock in the dihedral. Also extended the wing mast which was originally made for the Crossbow model-now it will work for both. It matches the mold at Falcon so it is exact scale......

    Picture illustrating the clearance under the ama hulls when the boat is sitting level:

    [​IMG]
     
  8. Doug Lord
    Joined: May 2009
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    Location: Cocoa, Florida

    Doug Lord Flight Ready

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

    Doug Lord Flight Ready

    WOLF---daughter of fire arrow

    Looking at possibly increasing SA from 165 upwind since the boat has more than enough RM. And that's figuring RM with skipper in the seat-not at max outboard and no downforce from the main foil.
    Want to foil upwind from 7-8 knots wind and foil offwind from 5 knots wind.
    More to come......
     
  10. Doug Lord
    Joined: May 2009
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    Location: Cocoa, Florida

    Doug Lord Flight Ready

    WOLF---daughter of fire arrow

    Rough notes on the sailplan for Wolf in prep for doing the final sailplan and weight study for the fullsize boat:
    ====================
    WOLF max SA based on max RM and tentative weight estimates:

    1) Max Sail Area-from the sketch:
    a. Black leech line-218sq.ft @ max weight(299 boat weight + 215 crew weight)=2.36lb/sq.ft sail loading.
    -
    b. Red leech line-192sq.ft.
    ---@ max weight(299 boat weight+215 crew weight)= 2.67 lb/sq.ft sail loading
    ---@ new target weight( 275 boat weight + 215 crew weight)=2.55lb/sq.ft
    -
    c. Tentative conclusion go slightly bigger than red line with bigger square top.(est 200sq.ft upwind SA)
    ---------------------------
    2) Max RM:
    a. Max RM from crew=3010ft.lb
    b. Max RM from boat(@299lb)=2392ft.lb
    c. Max RM= 5402ft.lb @max weight(299lb boat weight)/ (5200ft.lb @ 275lb target boat weight)
    ---------------------------
    3) Max Wind Pressure-based on 14' CE(before depowering/reefing) :
    a. 1.76lb/sq.ft @ max boat and crew weight(299lb +215lb).
    b. 1.7 lb/sq.ft @ target boat and crew weight(275lb +215lb).
    --------------------------
    4) Tentative max mast length=25'(.58'/7" chord)
    --------------------------
    5) Does not include RM from mainfoil downforce which will be substantial = +30 to 50%.
    --------------------------
    6) Need sail-loading at 2.8lb/sq.ft or less for upwind foiling(@7-8knots wind speed) and 5 knot wind takeoff.
    --------------------------
    7) Sail-loading with 200sq.ft. (upwind) plus 150sq.ft (downwind)-350sq.ft total at target weight of 275lb boat(max boat weight 299lb) + 215 crew is: 1.4lb/sq.ft.-which is excellent for light air speed and early(5knot wind) takeoff.
    --------------------------
    8) Mast rake(relative to static waterline)=5 degrees.






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    Last edited: Apr 13, 2017
  11. Konstanty
    Joined: Mar 2016
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    Location: Bydgoszcz Poland

    Konstanty Junior Member

    red line ?

    What does this red line mean?
     
  12. Doug Lord
    Joined: May 2009
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    Location: Cocoa, Florida

    Doug Lord Flight Ready

    WOLF---daughter of fire arrow

    The red line on the rough sketch is the leech of the rig reduced in area from 218 to 192 sq.ft. The final main will be a little bigger than the red line and smaller than the black line leach.
    Since this is a foiler, sail loading(lbs/sq.ft) is one of the main keys to its performance so I want the most upwind SA I can get within the constraints of the other elements of the design like daggerboard position(relative to the rig and the main lifting foil on the bottom of the daggerboard), ama foil position, method of sheeting/cockpit etc..
    This boat is wider than it is long and coupled with mainfoil downforce has extraordinary righting moment, particularly when mainfoil downforce is used.
     
  13. Doug Lord
    Joined: May 2009
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    Location: Cocoa, Florida

    Doug Lord Flight Ready

    WOLF---daughter of fire arrow--boom/sheeting

    As lightly drawn in on the sketch above the main foot will come down very low for over half it's length. That's going to require a variation on a wishbone boom
    with a "V" strut attached to the boom to facilitate sheeting. The traveller will be raised up so that the tiller and extension tillers pass under it.
    The mainsheet will be arranged to lead from forward and probably tied into the jib sheet in a manner similar to the Swift Solo which has a system of "relativity" to use to adjust the jib but both sails are sheeted at the same time.


    [​IMG]
     
  14. Doug Lord
    Joined: May 2009
    Posts: 16,679
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    Location: Cocoa, Florida

    Doug Lord Flight Ready

    WOLF---daughter of fire arrow / Concept Model

    Pix of inboard/outboard seating mock-up later today. A couple more shots with the (inboard)seats with high back:

    [​IMG]


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  15. Doug Lord
    Joined: May 2009
    Posts: 16,679
    Likes: 349, Points: 93, Legacy Rep: 1362
    Location: Cocoa, Florida

    Doug Lord Flight Ready

    WOLF---daughter of fire arrow / Concept Model / Two Level Seating

    This is a mock-up of two level seating with 3-4" cushions(not shown). Allows skipper to increase RM when required and/or have a comfortable easy change of seats.

    Seats with cushions in place. Designed for 10 degree angle of heel which is maintained by the wand controlled main foil in most conditions.......
    Lower seat-20", back 16"
    Upper seat -20", back 10"
    --
    Upper seat removable and foldable.


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    Last edited: Apr 16, 2017
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