Have you seen this?

Another skinny catamaran! What makes it so different from a dozen other variations I ask earnestly?
 
I dunno, the length of the totally submerged hulls? The advertising? I watched the vid, it all comes across really half arsed. Anyway I thought I'd ask the people who know about these things.
 
Nice graphics, nice site and all that but is there anything substantial in it? I doubt it -got all the hula girls and all that c-r-a-p!

Very entertaining I'm sure but really, is it of use, other than to waste away some time? I doubt it!
 
Nice cartoon work. Are there any real ones?
 
Oh, man, I got a kick out of this - it sounds like a poor bable-fish translation:

The cost of the feasibility study is part of architectural and engineering costs, estimated with total costs. Actual total turn-key construction costs cannot be accurately known until the architecture and engineering phases are completed for any specific vessel design. Since the Hydro Lance has approximately 30% more area of skin and ribs, we project that the material and construction costs, beyond the first like ship, may have about the same percentage of cost increase, then having lower costs in mass modular-production, as compared with a conventional ship. Depending on the selected construction ship-yard, a capital cost of approximately $12,000-18,000.00 per displacement ton of ship constructed, is a "thumb nail" estimate of the first mission specific HARTH blue-water class ship - from womb to operational status, depending on customer requirements and custom variables.

The variables of the mission statement, the 'luxury factor' of interior design of each application and client, and other technical variables make a more accurate cost/price estimates impossible to make, until the Architectural and Engineering phase of each ship is completed. This is, of course, the same for any new conventional type ship to be constructed. Noteworthy is that a conversion, made from certain types of existing vessels, could save up to half of this cost (See Conversions), or more.
Click to expand...
 
That was kinda painful to look at, man.
 
Looks straight out of an early-'60s Popular Mechanics, if you ask me.

Land-based construction estimators can usually give you a pretty decent guess at cost given 50% completion of design documents. For something like this to be credible it would need at least an order-of-magnitude estimate...
 
I suggest a "Fantasy" section, so we could move the thread. :D
 
Well yeah, he obviously hasn't got very far, he's no kid in the vid. Silly claims aside I was more wondering if there was enough merit in the basic idea to make it worth pursuing or if it suffered some fatal flaw. I can think of a few issues in harbour with a craft that's configured like that. Would the numbers come close to stacking up for a craft like that? Done correctly has he got a point from a designers perspective or is it just so much bull.
 
I would say yes, he does have a point. Long, slim hulls do have a lot of technical advantages going for them.

Where the argument breaks down, I think, is that here it has been taken to the extreme. The vessels described have such incredibly long, slender hulls that I have to question both the potential for sufficient volume to actually float the thing, and the structural complications involved in applying loads of several hundred tons on extremely slender and lightweight tubes of a couple hundred feet in length. I see little to no reserve buoyancy, thus limited load capability and a major seaworthiness issue when wave height is comparable to bridgedeck height. I question whether the enormous increase in surface area compared to a more traditional cat of similar weight will really be offset by the reduced wave drag. Similarly, the claim of maintaining 65 knots in a Force 6 with no yaw, pitch or roll does not strike me as realistic. (Although I was at least a bit entertained by the one where the HARTH hulls are Photoshop-grafted to the belly of a Boeing 727.)

Not to bash the fundamental idea, of course- long, slim hulls are a very good engineering solution in a lot of cases. I just don't see the evidence that this one has been thought through.
 
I agree with Matt. There have been some well publicized cases of surface piercing multis breaking a hull immediately in front of the forward crossbeam. That's where the stress ends up being concentrated.

A second problem is sinkage/payload. The tons per inch immersion (that's how we yanks say it anyhoo) is a function of waterplane area, so changes in displacement and LCG due to changes in payload, fueling, provisioning, etc. will tend to sink a small waterplane multihull disproportionately.

Once it is sunk, stability can become an issue. Let's say a catamaran with low freeboard hulls is loaded such that the hulls are almost immersed, and wind, waves, and shifting load heel it to one side. There isn't much reserve bouyancy there, and this can become a dangerous situation. The capsizing of the pontoon boat Lady D in Baltimore Harbor is a case in point: http://www.ntsb.gov/publictn/2006/MAR0601.pdf

Most of the big cat ferries balance these issues pretty well. Looking at those from the largest Australian builders I'll hazard that the surface piercing INCATS push the limits a bit more than the more conservative cats from Austal, but craft from both these companies have good track records. The ones that carry cars must deal with a higher payload than the ones that are strictly passengers. There are plenty of catamaran container ship proposals out there -- but the issue again is having enough waterplane to deal with the payload variables.
 
HARTH Technology

I've noted a very interesting pool of visitors to our website this past weekend. First, I thank you for having taken an interest in the HARTH Technology, Hydro Lance Engineering and the Hydro lance Corporation.

New technologies, concepts and innovations are understandably difficult to visualize. When I was young, the very idea of a 'live picture' coming through the air to a box-with-a-window, was 'mind-boggling' and took some time to grasp how it actually worked. The same was true of the transistor and the marvelous pocket radio replacing plug-in tube radios, and having better reception and big sound. Then came the PC, etc.

Here we are again. The HARTH technology has a strong foundation of real research, science, physics, engineering and testing confirming this reality. And yes, there is no roll, pitch, heave, yaw or sway during operation of the ocean vessel. No bow wake and low surface resistance. This is the first series of vessels first designed for the ocean rather that a boat slip.

Having skimmed over the dialogs, I see the Lady-D being used an example of decent. The Lady-D is first a catamaran. The Hydro Lance is NOT by any definition, with the exception of having more than one hull, a Catamaran, trimaran, SWATH, hydro-foil, etc, but rather a very different discovery.

The forces of waves, or ocean contours, are averaged to a near zero influence on the hulls or vessel. With speed, the hulls become more rigid from hydrostatic pressures. Hull displacement is designed to be far greater than the entire ship required displacement. Sections of a hull might be lost in some incident and the ship would still maintain an upright integrity in elevated sea-states.

These are not your grandfather's row-boats. Should you have a question that I might help you with, always feel free to contact me, or any of our senior staff for some technical resolution.

I hope this has been helpful. Thank each of you for your interest with discussing the questions observed.

Have a good day,

WR
HLE
 
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