Wavepiercers, Trimarans, SWATH and such...

another low wash from Austria for Venice

I will give you this link for other low wash developments.

http://www.alsphere.at

It's from Austria but in English.
The picture is from this web site ... and shows the low waves behind the boat at 18kn.

some more wave-piercing multi-hulls,
Water Wizards, a 50 ft power cat designed by Tim Kernan of Kernan Yacht
Design (formerly Waterplane), used as a photography/filming platform for yacht races, very long distance capable, with barely any wake.
http://oceanfilmboat.com/

Tim is also working with the new "M-hulls" more information and images can be found at his website.
http://www.waterplane.com/

New Ground effect craft

Check this out,

http://www.gizmag.co.uk/go/6835/

Solution seem a bit complex but I'd love to experience the ride with thos big shock absorbers.

No photos actually fully in ground effect so I'm wondering if it just operated with ground effect assistance.

That brings back certain memories ....

http://www.aero-web.org/database/aircraft/getimage.htm?id=7406

YES I knew I had seen something like that before, I think convair made a large twin turbine Sea plane, she was a beauty, if you can source any photos id apreciate it.

I have done some searching. The historic photos I could find online, taken back when the plane was being flown, are generally poor quality. There are a few at museums, so modern digital photography is still possible -

http://www.fiddlersgreen.net/AC/aircraft/Convair-SeaDart/Seadart.php

Kelly

Thanks K1W1!

Triple Hulls

As our call sign, tri - star; - suggests:
We are involved in the design and engineering of vessels with TRIPLE HULLS.

At the moment: We can not send you any pretty
pictures of our gorgeous looking protypes.
As so much of what we are doing now is
proprietary.

Having designed and built:- monohulls, cats and tris....and as I'm on a short list of people that have operated triple hulled craft beyond 60 knots.....
Perhaps; it is appropriate, that I put some real world experience forward ?

First, you will notice, I avoid the word trimaran.
As does the British Navy.
They prefer the term " stabilised monohull ". Which is possibly accurate, but lacks a certain poetic flair.
Currantly with most sailing trimarans - all the hulls are close to the SAME length.
For very sound reasons. Like needing to resist pitch
poling, in the diagonal - caused by the heeling force of the sails.

Typicaly, a triple hulled vessel, UNDER POWER, has much less of these forces to contend with.
No SAILS......
So the outer hulls can be significantly shorter.
In effect: this is a distinctly, different craft, in many ways - from what is commonly referred to as a trimaran.
So I have been searching for a different name, for this new type of vessel.
Serious suggestions are welcome.

Now to more critical concerns:

There have been disasterous vessels created of all types. Also, within specific parameters, successful ones as well.
With strong evangelists for; single, double or triple hulled craft.
Let us not go into this too much, right now......
Please !! I'ved heard it all....many times....

Suffice to say:
Personaly, I have found that a WELL DESIGNED triple hulled vessel has merit.
Specificaly in terms of:
FUEL EFFICIENCY and SEAKEEPING.

If you question the above - please pause for a moment - and consider why the the US Navy, is presently engaged in a billzillon dollar project involving triple hulled ships ?!

Cheers all !

Good points tri - star. The design of White Rabbit really intrigued me. I was hoping to see some reports on how well that yacht worked out in the real world. But have not seen a peep after the initial fanfare. Heard any scuttlebutt?

Kelly

In sailing there are now many trimarans that are actually sailing on the "outrigger" hull, like this one from Marc Lombard; http://www.oceanlakemarine.com/

Some trimarans are instead called Wavepiercers and are almost catamarans with a center hull, and then there are the ones with just smaller and more narrow side hulls aft, like stabilized monohulls.

But I still like to call all of them trimarans, or perhaps just multihulls...?

Tri Hulls.....

To KCook:

I will give you pertinent data when it's available.
However, there is difinately...an interesting LACK of
reporting......
Including. info. that I know will excite interest - that
I'm not at liberty to release, without upsetting the
people I'm involved with.
As far as the big Australian yards go, their retinence,
one can conclud - is related to the fact that they are
" imbedded " into the US, Littoral Combat Ship program.

To AMG:
I agree with all that you say and personaly like the
word Trimaran.
It certainly flows better than the term,
" stabilized mono".
However, when reliable data does finaly surface re:
POWERED TRI - HULLS, I predict, that the performance
profiles seen, will demand different terminology.

Cheers All !

Hydroptere

Tri-Star,

you must be happy to hear that a trimaran is a very serious contender to be the first to break the 50 knot barrier (average on 500 m) for sail-powered vehicles. It's the fastest sailing boat around now for sure.

It does have some foils under the waterline to help though. Have a look at www.hydroptere.com. Some cool videos of speeding in heavy seas.

Everyone's going for that 50 knot barrier (in windsurfing, kiteboarding and sailing) and 2007 may just be the year that we break it.
For the interested, the record is now in the hands of the windsurfers at 48 knots and a little something. But the kiters haven't been around for long and are approaching fast...

Bruno

50 Knots !?

Great graphic Innomare:

I will admit to perhap; a slight basis and regard
for tri - hulls, that may seem to verge on the
evengelical at times.

However, I will stray into the enemy camp - now
and again.
As with Windsurfers. In '83 I made a few wing sails
for 'surfers. Then the record stood at less than
30 knots - and I predicted this speed could be attained
by a Windsurfer with a wing sail. - And it was.
Unfortuneatly, NOT with one of the sails made by me....
Could not find a sponser, with vision, in time... O well...

It is interesting, that much, that was true then - still
applies now.
So I will make another prediction - that the 'boarders
will continue to have the edge in these speed trials.

We must be ruthless, on occasion - and put aside
inclinations - towards any particular hull form.

If the trials were over geater distances, futher off shore.
A tri - with appendages - is my first choice.
However, if a tri - hull is like a Steeple Chase race horse.
A Windsurfer is closer to being a Quarter horse.
And has the advantage. In what amounts to more of
a drag race than most other sail boat races.

It's the simplicity of the boarder's rig that is the key.
As in:
Having NO rudder. With often, just ONE foil below decks
and minimal rigging.
Also consider, the elegant economy, of forcing the
pilot to function as PART of said, rigging. As they
attempt to steer - less than 12 square inches
of wetted surface - in a straight line!

Also, aerodynamicaly, the surfer presents, very minimal
frontal area to the wind. Then there's the INHERENT
reliability - of a minimum of componants.

This is hard to beat.

Especialy, as your TRI - FOILER gains in complexity and
acquires more and more accumulated drag, the harder it
attempts to exceed 50 knots.
At the moment, the challange for lifting foil boats, does not
seem so much about going fast, as:
Keeping all the little bits and pieces attached to each other!

Well...I wish them all luck!
It takes courage and determination to do what they are
doing. So God speed.

Cheers !

After getting started at 4:00 AM and now at the end of a long first day of the Miami Show, I'd like to formulate something remotely coherent, but I'm too tired to type. If you will forgive me for being brief, and slightly tongue in cheek, there's a BIG difference between military protocol and luxury yacht accommodations! Just thought we should keep this in mind while discussing the merits of trimarans. Also, don't forget slip space!

Night all! Catch ya after the show.

Carl

So whatever happened to...

military hydrofoils?
Late '70s-early '80s, out fishing off Marathon ( Fla Keys) on the bay side, summertime.
Off in the distance is this pretty danged large ( 100+ ft.), and obviously Naval vessel, making serious speed. I mean, she is GONE in a matter of a few minutes, over the horizon. Stacks looked like gas turbine-powered.

Any info about then, as well as why currently, they have "faded away"?

TRI HULLS...hydrofoils

To C.Camper:

Re: "....accomodations...."
Yes we agree; if having the maximum amount of
Staterooms possible - is the biggest concern - then
a high performance, muti - hull is possibly, not the
best choice.

Also, as Navies have been known to stack personal
like cordwood......
- And max. pursuit speed, in ALL weathers is required,
it's just possible, that a Naval tactition might not worry
to much about the Captain losing a little cabin space....

Re: "....slip space...."

We realize that you were tired and proberly did not have
the time to read my submission carefully.....
In which I detail, at some length, as to why I do not
refer to our POWER TRI - HULL vessels as trimarans.
Partly, because, people will tend to make the same
presumption that you just did.

To repeat:
As there are NO SAILS - a triple hulled vessel under
power, does not have to contend with the large
heeling forces, as can be generated - by billowing
clouds of canvas.

Therefore; as a high resistance to heeling is not
required with a Power Tri, the outer hulls can be a lot
shorter. Also EXCESSIVE BEAM is no longer of any
performance advantage.......
So concerns about getting into slips - with our designs
- and others, HAVE DIMINISHED.

Also, tis folly, to so quickly brush off, the Billion or so
Pounds the British have spent on a "stabilized monohull".
Or the many, Billions of US dollars, presently being
spent on high speed ships. Some with semi - planing
hulls (?) - and some in a tri - hull configuration.

What IS it?! That these Navies know?
That the marine world, in general, is not yet aware of....

To Loren Schweizer:

Re: Military HYDROFOILS.
At one time, CANADA possessed the worlds fastest
Destroyer. 60 knots or so....With hydrofoils. Cost about:
$ 6 Million. Sold to the US Navy.

You might wonder why, BOTH, civilian and military
hydrofoils have faded quietly from sight....
One possibility is: the ALL or NOTHING aspect, of
hypercritical foils.
i.e.
I belive there was a Hydrofoil Ferry, in service,
in Japan.
That fell forward. When it abruptly lost lift....and came
to a crash stop.
I was told, that a Grandmother died instantly.
Foils have a certain magic - however.....

All for now, chaps!
Obviously, I have had too much time on my hands
- waiting for clients to make up their minds.
However, this just changed and I will be busy in design
mode for the next little while.

Later.....

Err, I think this brings up a point. Most, if not all, exotic or very high performance hull designs are optimised for a very narrow speed range. Compared to conventional hulls. With these new stabilized monohulls, or tri-hulls, or whatever, I wonder if this operational limitation still applies? I'm not arguing that it does, but just wondering out loud.

Kelly

I think I have the answer to this. Most people know, since decades, that multihulls has many advantages over monohulls. However they LOOK DIFFERENT and this is where a Navy has no objections. Very few trimaran yachts today are truly good looking and I think most yacht buyers want to hear that they have a beautiful yacht!

When we can come up with designs that are appealing in itself, not just in performance, then I think trimarans will become much more appreciated.

Good point by Lars. I would add that size is an important factor as well. Very, very hard to make an attractive 40' tri-hull. White Rabbit is an exception, but also a pretty large yacht. It does puzzle me that so few megayachts are multi-hull.

Kelly

To AMG and Kcook:

Gentlemen you must be exceptionaly intelligent and
sophisticated people.
- Because you so often agree with me!
i.e.
AMG, "....trimarans will become much more appreciated."
Kcook, "....hard to make an attractive 40ft. tri - hull."
"....White Rabbit is an exception."
Although, it's proving to be far easier, to achieve positive
aesthetic results with our tri - hulls than cats. Even in the
shorter lengths......
As I will demonstrate, once my associates have resolved
our immediate, proprietry and financial concerns.

After several long years of R & D - I'm looking forward to
our " Show and Tell ".