Have you seen this?

[Meanz Beanz]

http://www.hydrolance.net/

Is this guy deluding himself or does he have something?

[rwatson]

Another skinny catamaran! What makes it so different from a dozen other variations I ask earnestly?

[Meanz Beanz]

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.

[the1much]

anyone that says they can build a boat that will never cause sea sickness is about as stupid as the person that came up with that idiotic design.

[safewalrus]

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!

[ted655]

Nice cartoon work. Are there any real ones?

[Manie B]

To me it looks like another 20 something year old snot nose on drugs drawing pretty pictures and elaborate websites, more evidence of the playstation generation.

no sea sickness ever - please please please
stop talking ****
it will take years to do the stress analysis alone

[DanishBagger]

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.

[tinhorn]

That was kinda painful to look at, man.

[masalai]

Another misogynistic masturbator (only said that because the words seem appropriate and go together)

[marshmat]

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...

[ted655]

I suggest a "Fantasy" section, so we could move the thread.

[Meanz Beanz]

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.

[marshmat]

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.

[Stephen Ditmore]

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.