18' Trimaran vs F18 Catamaran

Discussion in 'Multihulls' started by Doug Lord, Jun 13, 2010.

  1. powerabout
    Joined: Nov 2007
    Posts: 2,925
    Likes: 66, Points: 48, Legacy Rep: 719
    Location: Melbourne/Singapore/Italy

    powerabout Senior Member

    an F16 can beat an F18 around the cans in anything lower then about 10kts with the same crew weight.
    Dont forget the F18 is about 40kg heavier ( 60-70kg heavier than an F16) than it could be..( thanks to hobie)
    Its as heavy as a Nacra 20 that has a mast bigger than a tornado!
    F18 is a boat built to a box rule, hardly cutting edge/optimised?
  2. Stefan H
    Joined: Dec 2009
    Posts: 32
    Likes: 2, Points: 0, Legacy Rep: 40
    Location: Sweden

    Stefan H Junior Member

    Windrider Rave is possibly faster in high wind/ flat water conditions, I believe its about 18ft (5,2m).
  3. Doug Lord
    Joined: May 2009
    Posts: 16,679
    Likes: 342, Points: 93, Legacy Rep: 1362
    Location: Cocoa, Florida

    Doug Lord Flight Ready

    Could be.....about the same weight with less SA, but far more power than an F18:

    WindRider Rave Specifications
    Length 17' / 5.2 m
    Beam (foil tip to foil tip) 17' / 5.2 m
    Beam (trailered) 7'6" / 2.3 m
    Weight 400 lbs. / 182 kg
    Total Sail Area (Main & Jib) 195 sq. ft. / 18 m2
    Addl. Sail Area w/ optional Reacher +97 sq. ft. / 9 m2
    Draft (foils up) 1' / .3 m
  4. lane
    Joined: Dec 2005
    Posts: 22
    Likes: 0, Points: 1, Legacy Rep: 10
    Location: Austin TX

    lane Junior Member

    Here is a homebuilt simple boat to test the limits of an 18ft tri. 16ft beam and lots of tramp room.
  5. playmaker
    Joined: Jan 2010
    Posts: 6
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Milano

    playmaker Junior Member

    I am naval student working about powered catamaran stability. Is reasonable handling only one hull to calculate stabilty and hydrostatical curves?
  6. Doug Lord
    Joined: May 2009
    Posts: 16,679
    Likes: 342, Points: 93, Legacy Rep: 1362
    Location: Cocoa, Florida

    Doug Lord Flight Ready

    F18 vs 18' tri

    It is my opinion that a trimaran that would beat an F18 and other beachcats under 20' could be done without using all the considerable reserve power available in a trimaran( twice the RM+ of any beach cat for the same crew weight) and that while the boat would probably need to use a version of "foil assist" it would not have to be a full flying foiler.
    Emphasis could, instead, be placed on comfort and easy to manage power.

    While this is about catamarans from an interveiw with Martin Fischer, I think it applies to ALL multihulls-most particularly a trimaran that could accomplish the challenge of this thread:

    CS - Is possible to see in the future a stablished racing class of foiling beachcats ?
    MF: Yes, I am absolutely convinced that foiling multihulls are the next step. The challenge is to make them reliable and easy to handle. I am currently working on putting an A-Class on foils. First tests are very promising. I start flying the boat, also it is not very stable yet, but I think we will get there.

    CS- I've heard from Landy in the A-Class, from M20 pics and reports and from Macca in the Nacra F20 how they are flying with curved boards, so slowly we are going in that direction, not full hydrofoils of course, but is the future in your view (flying beachcats Moth style)?
    MF: Yes, I have here in New Caledonia an A-Class with curved foils. The boat works nicely but it is not yet fully air-borne. If everything works according to plans I’ll have a flying A-Cat before the end of the year.

    The full interview is here: http://catsailingnews.blogspot.com/2010/05/cs-interview-martin-fischer.html
  7. Chris Ostlind

    Chris Ostlind Previous Member

    Prove it
  8. lane
    Joined: Dec 2005
    Posts: 22
    Likes: 0, Points: 1, Legacy Rep: 10
    Location: Austin TX

    lane Junior Member

    A modest Tri-Posal

    Just loaded the picture of my little trimaran. Tri-Again is a homebuilt simple boat to test the limits of an 18ft tri. 16ft beam and lots of tramp room, for sunbathers.

    Attached Files:

  9. Doug Lord
    Joined: May 2009
    Posts: 16,679
    Likes: 342, Points: 93, Legacy Rep: 1362
    Location: Cocoa, Florida

    Doug Lord Flight Ready

    Hi Lane, have you sailed the boat? What rig are you using?
  10. Chris Ostlind

    Chris Ostlind Previous Member

    Still waiting for the proof that a foil assisted 18' trimaran can be produced for the same price and quality of fit and finish as an F18 Capricorn.

    Get those pencils out boys and girls and give Doug a hand. I have a feeling he's planning on manufacturing the boat in Rwanda, where the Tutsis will do the work and the Hutus will run the factory. ;-)

    One is simply not going to be able to make a comparable trimaran with three hulls at the same price as one can produce a wildly hot boat that has only two hulls.

    BTW: Nice effort, Lane. After those conversations many years ago, it's nice to see it realized and on the trailer headed for funville.
  11. Doug Lord
    Joined: May 2009
    Posts: 16,679
    Likes: 342, Points: 93, Legacy Rep: 1362
    Location: Cocoa, Florida

    Doug Lord Flight Ready

    Magnum 18S performance tri

    What this proves is that a performance tri can be built and sold for $19,235(including spinnaker)
    compared with the cost of the state of the art Wildcat F18-the latest creation of Martin Fischer and Hobie- at $22,499(not sure this includes all sails-see below). It probably isn't as fast as an F18 though it can be sailed singlehanded which makes its sailing weight substantially LESS than the F18.
    For the performance,design and comfort enhancements I'd probably include in a final design the two would be close in price-with the tri more comfortable and faster.


    1) Construction--Composite glass/polyester
    2) Hull Length-5.30m (18ft)
    3) Float Length -3.8m
    4) Float Volume -200 litres each (filled with bouyancy) -451lb. buoyancy in salt water. VERY IMP: this means that this boat cannot fly the main hull since there is no method of dynamic lift associated with the ama.
    5) Widths:
    --4.30m trimaran overall
    --0.92m (max) Principle hull at waterline
    --1.72m on the road
    6) Mast length -18: 7.0m 18S: 7.30m
    7) Mast height above waterline -18: 7.75m 18S: 8.05
    8) Standard Sail Areas
    --Classic 18: Main 11.5m2 18S: Main 12m2 129 sq.ft.
    --Classic 18: Furling Jib 4.5m2 18S: Furling Jib 4.75m 51
    --Total upwind SA 18S-180 sq.ft.
    9) Draught 0.2m ,1.0m with centreboard down
    10) Weight 200kg

    11) Standard Rigging:
    --Rotating mast.
    --Full battened main with downhaul.
    --Furling jib is standard.
    --All sheets and halyards supplied.
    --Trapeze kit optional on classic 18 but std. on 18S
    --Composite (racing) rudder foil std.
    12) CE Classification-Category "C" (unsinkable)


    Hobie Wildcat F18

    Hobie Cat Europe asked a panel of esteemed naval architects(Martin Fischer-see interview url in a previous post), Olympic sailors, and sailmakers to design and build an F18-class category killer. The result? The all-new Hobie Wild Cat F18. This no apologies racing cat will unquestionably make its presence known in F18 racing. Wave-piercing hulls, integrated wing mast section, and minimal drag from its high-aspect rudders and centerboards contribute to outrageous lift when sailing to windward. Downwind is a sleigh ride with the full spinnaker rig. Whether fleet racing or blistering across the water for the sheer thrill of it, the Wild Cat will most certainly satisfy your need for velocity.

    Standard Features:
    >> Fiberglass hulls with EVA anti-skid and one inspection port at the rear
    >> Carbon reinforced rudder blades and daggerboards
    >> Carbon telescopic tiller extension
    >> Mesh trampoline
    >> Harken mainsheet blocks
    >> Harken spinnaker blocks
    >> Spinlock Cunningham blocks
    >> Jib tack line and jib sheet integrated in the front crossbar
    >> Spinnaker tack point and spinnaker halyard are separated
    Type: Hobie Wildcat F18
    Hull: multi
    Year: 2010
    Length: 17'11"
    Beam: 8'6"
    Draft: board up: 7"; board down: 4'2"
    Weight: 397 lbs
    Upwind SA: 227 sq.ft.
    Sail Total Area: 454 sq. ft. upwind and downwind
    Base Price: $22,499-includes everything( 6/21/10 )
    Intro Year: 2009
    Designer: Hobie Cat Europe Design Team

    Attached Files:

    Last edited: Jun 21, 2010
  12. Chris Ostlind

    Chris Ostlind Previous Member

    That's a funny and desperate shot to make your argument, but it's not going to get it. I take it that you've never actually seen a Magnum 18 in person have you?

    Magnum 18's are seriously heavier, have much smaller sail area and do not accelerate the way the Wildcat can, no matter who is having the dream. A Wildcat can sail circles around a Magnum 18 even when the Mag skipper has the pedal to the floor. The single handed potential of this boat only applies to the non-spinny rigged version. Add the spin and you add crew. Put a competitive rig on that Magnum, find some way to build the boat lighter while still being able to handle the loads of the much bigger rig and the fancy foils in the amas and the price goes through the roof.

    You are whistling in your head, son... and you haven't even added the engineering that has to be amortised and all the spendy sail handling hardware that a sailor of this type of boat would expect. I'd really like to see you try to sell an expensive foiling boat with romper room hardware that won't last one season.

    You want cheap, you get heavy and slow. You want fast as an F18 and you get big time expensive. Go back to the Internet scan, Doug. This attempt is DOA.

    Why do you do this... you know, set yourself on fire for a cause that can't be supported in the real world.
  13. Traxxasmaxx
    Joined: Jun 2010
    Posts: 10
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Florida Gulf Coast

    Traxxasmaxx 1978 Johnson Seahorse

    Holy Smokes! This post has gone crazy! Fun to read
  14. Doug Lord
    Joined: May 2009
    Posts: 16,679
    Likes: 342, Points: 93, Legacy Rep: 1362
    Location: Cocoa, Florida

    Doug Lord Flight Ready

    You're caught dead to rights. You simply can't admit when you're wrong-very wrong.
    Weight difference 44lb. SA difference 50 sq. ft.
    So if you REMOVE the weight at the cost per lb of the Wildcat you get 44 X 56= $2464 . Add SA at $15 per sq.ft= 50X 15= $750. Total additional cost: $3214
    Tri as it is now: 19,235 add $3214 in improvements TOTAL COST IMPROVED TRI= $22,449 (cost F 18-probably w/o spin= $22,499)
    There you go-a tri comparable to an F18 for about the same cost.

    You're also wrong about the spinnaker-especialy on the F18 killer: since it flys the main hull with "dynamic heel control"(foils*) and has dynamic lift designed into the ama the boat would just fly with the spin....
    *foils add no cost: F18 Cat has TWO daggerboards and TWO rudders. F18 killer tri has ONE daggerboard(with small lifting foil) and ONE rudder(with small lifting foil)-no net gain in cost.

  15. Chris Ostlind

    Chris Ostlind Previous Member

    First of all, Doug... I can admit I'm wrong. It's just that you haven't proven anything that would require me to do so. Pulling a cost per pound coefficient out of your butt for a boat that is head and shoulders more developed and more professionally finished is as foolish a practice as I've ever seen you perform.

    Let's see now, a resuscitated Yugo weighs 3000 lbs. and a Porsche 911 Targa weighs..... yep, all we have to do is apply Doug's magical, out of his butt, coefficient and Whammo!!!!, we can produce fabulous Yugos that are every bit as good as a Porsche Targa. Yes, that Yugo would be a car I'd love to drive with a smile on my face.

    Secondly, you seem to have, at least, some modicum of respect for Martin Fischer and his professional skills. What you have just done in this tawdry comparison is reduce his input on the Wildcat to something a good deal less by simply inferring that the Magnum hull has gone through a similar engineering regime to arrive at an optimal hull.

    If you can't rise to their level, I guess that it's OK to drag them, screaming and kicking, down to yours.

    Good work, Doug, I'm sure that you'll influence thousands to start putting in orders for boats of that sort.
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.