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[edit] Means of Navigation

Means of Navigation seems to me to have very little to do with Naval Architecture per se. It has more place in articles on Navigation Lights (usually mount green to starboard and red to port?) and in ones on Navigation. I have suggested this section be split and moved/merged into those two articles

Fiddle Faddle 16:26, 17 April 2006 (UTC)

I would tend to agree. In general this definition does not describe commercial / naval design as much as recreational vessel design concepts. The issues of propulsion and stability are not well defined and the role of regulatory bodies such as Lloyd's Register and the American Bureau of Shipping is not addressed at all.

I would recommend a wholsale re-write.

agree re rewrite. I have also performed both merges today Fiddle Faddle 10:03, 4 May 2006 (UTC)

[edit] Froude Number

"Generally, the speed of a vessel is critical to its efficiency. The basic speed of a vessel is its hull speed. For hull speed of displacement (non-planing) vessels, adding more energy to the propulsion has little effect on the speed. For this type of vessel the maximum efficient speed increases as the square root of the waterline length. This relationship is known as the Froude number Fn = ( Speed in knots / (Waterline length in feet)^0.5)"

Is this number the same as that in Froude number?

Fiddle Faddle 22:13, 3 May 2006 (UTC)

There are more than a few inaccuracies in this entry. The whole thing seems to be a bit of a meander between yacht designer and naval architect. I will attempt to sort it out and add some references once I get a bit of time. Jmvolc 02:36, 16 May 2006 (UTC)

That would be great. I've split "Naval Architect" away form "Naval architecture" on the basis that one is the science and the other the profession, but I've run out of technical ability to do more than tidy things. To stay in metaphor, that is deck chair re-arrangement, so it needs a subject expert to make it work :) Fiddle Faddle 07:26, 16 May 2006 (UTC)

[edit] Cleanup

The topic deserves more information gathered into sections that are less rambling. There are many good parts to this, but they warrant organising.

We have a mish-mash of pleasure craft and commercial craft. But that is, surely, not what naval architecture is about. It is about the mixture of practical and aesthetic design to create a vessel that does its job efficiently and economically - as true for a racing yacht as for a container ship.

Additionally there are items that simply do not belong here. Those are highlighted with merge tags already, but there may be others, too.

This is a large task, and would be best performed by a knowledgeable person rather than a casual "editor of language"

Fiddle Faddle 22:23, 3 May 2006 (UTC)

[edit] Merge / Split suggestion

Looking way back this article was about Naval Architects, not really about Naval Architecture.

I'm removing the extraneous matter, thatwhich has nothing whatsoever to do with Naval Architecture, and also suggest a split into Architects and Architecture

the page "Naval Architect" is a redirect page to this article, but that is not correct. One is the role and the other is what they do. Thus one shoudl tal about qualifications and the other about the job itself and techniques etc. Thsi means the redirect page needs to become a disambig page. Will do that, too.

Fiddle Faddle 22:26, 13 May 2006 (UTC)

[edit] Proposal for Re-writing this Article

A few points up front:

• I’m of the mind that Naval Architecture and Naval Architects could be dealt with in the same article.

• The article seems to talk around the issue of Naval Architecture and does not hit the main points directly. These are:
  • Configuration
    • Hull Shape
    • Cargo/Weapon spaces
    • Tanks & Void Spaces
    • Machinery Arrangement
    • Accommodation
    • etc.
  • Weight & Centers
  • Hydrostatics
    • Displacement
    • Stability
  • Hydrodynamics
    • Resistance
    • Powering
      • Mechanical
      • Sail
    • Seakeeping
    • Manouvering

• The disciplines of Marine Systems, Electrical and Combat Systems Engineering should be mentioned as on smaller projects, these tasks are often undertaken by the Naval Architect.

• A distinction between Yacht Designers (ex: Nathaniel Hereshoff, Colin Archer, Gary Mull) and Naval Architects working on commercial and Naval platforms should be made. It is significant as the background and skills are grounded in the same theory but quite different in application.

• Some text on the history of Naval Architecture and the first recognized figures (ex: William Froude) should be added.

• The text on the various criteria is probably more technical than required here and is incomplete as it is.

• The remaining text seems to make an attempt at providing a thumbnail lesson in Naval Architecture. I'm not convinced that this adds to the understanding of the subject. Example : The text on Hull Speed is incorrect and incomplete. The correct term is Speed-Length Ratio. "Hull Speed" is a term coined by early yacht designers to describe the point at which the wave making resistance of a hullform increases dramatically with speed. In reality, the ratio (1.34) is often exceeded by high-powered displacement vessels. Furthermore multi-hulls are subject to exactly the same hydrodynamic rules that monohulls are with the added complication of hull interactions. Speed-Length Ratio has been replace by the non-dimensional Froude Number(Fn = v / (g L)^0.5). This sort of thing is probably best left out of the article to improve general comprehension.

• Naval Architecture is about shape and function - I would like to see a lot more images.

Please advise if I can make a stab at this or if that would be considered improper.

Cheers, Jmvolc 22:49, 16 May 2006 (UTC)

Suggestion: be bold

Write it. Obviously you will keep the good points of this along with the points you are adding.

no issue with incorporating the architect with the architecture as long as it does not turn into the curent fog. But, if it is separate, why not link to it with a synopsis and a "main article" link? This might give the clarity that is needed

Where the content becomes overly technical, why not use the "synopsis and main article" technique?

If we assume the current article is a good inspiration piece, and acknowledge that it took work to create, then I see that your efforts will be approved of. Of course others will leap in and edit, but that is what WP is all about.

Fiddle Faddle 23:08, 16 May 2006 (UTC)

Oh, and if you can explain how (eg) a Tornado cat (20' long) can hit 30 knots without planing or dragging a huge wake (that Hull Speed technical explanation) then you'll answer a load of questions! Fiddle Faddle 23:11, 16 May 2006 (UTC)

... I can but it's gonna hurt

Resistance can be broken down into two components frictional resistance and wave-making resistance. Frictional resistance is a function of the surface area immersed in the water (Wetted Area). Wave making resistance is a function of the square root of the waterline length (Froude Number) and the displacement. A Tornado Cat has a very low wetted area and a very low displacement for it's length. Note that it does not have a shape that can generate any dynamic lift (planing) so it always stays in a displacement mode. At high speeds (Fn>=1.0) the wave making resistance varies approximately as the square of the displacement. Due to it's very light displacement it generates a very small wave train allowing it to power well beyond its "Hull Speed". This is also facilitated by by virtual lengthening caused by the boundary layer and the immersed transom.

At 30knots the Fn for a Tornado (LWL=6.10m) is ... Fn = 30 x 0.5144 / (9.81 x 6.10)^0.5

    Fn = 1.99  
    The "Hull Speed" is around 6knots!!

There is no 'silver bullet' the hull is just very well suited to go fast. Jmvolc 00:04, 17 May 2006 (UTC)

Didn't hurt that much :). I even understood it!

Question: This looks from a non expert's viewpoint as something that should be part of either the main article or a sub article on boat speed theory. I suspect it would make the Naval Architecture article unreadable, but it looks highly worthy of a separate article. Fancy creating it (or checking to see what is around and editing them to include it?

Fiddle Faddle 07:02, 17 May 2006 (UTC)

Curiously enough, there is an entry on Hull speed and what a sorry mess it is. I would like to delete it in its entirety and re-work the Hull (watercraft) article to address Froude number is a simple manner. What do you think? Jmvolc 00:53, 18 May 2006 (UTC)

I'd go for it. I just looked at it. It has facts but no information. It is a great start, but not encyclopaedic, in the sense that it still requires translation in order to be useful. Frankly, where there is a mess I think it is wise to assume that no-one else will do it, so go ahead. Fiddle Faddle 06:19, 18 May 2006 (UTC)

[edit] Re-write

I have followed the guidance provided by the contributers to this discussion and boldly re-worked the article while still using much of the original content. It is shorter and hopefully addresses the subject matter completely, succintly and plainly. Please provide any comments, queries or criticisms here so that the article can be further improved.

Jmvolc 00:29, 7 December 2006 (UTC)

This is potentially an interesting page. However there is still too much vague and self congratulatory material. I don't have the knowledge to rewrite, but this is not of encyclopaedic quality.

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