Flatop (Aircraft Carrier) Decks

[RatliffFranklin]

It is interesting to me that no matter the price tag of a luxury yacht, the deck is never wider than the hull.

[kach22i]

Something tells me that you might want a active stability system on such a boat as it could be top heavy and prone to capsizing.

http://www.boatsafe.com/nauticalknowhow/captpat1.htm


The image is just to get a picture of the forces at work, nothing else.

Moment arms and things........................

http://www.nmri.go.jp/eng/khirata/st...n/index_e.html

[RatliffFranklin]

Originally Posted by kach22i

Something tells me that you might want a active stability system on such a boat as it could be top heavy and prone to capsizing.

http://www.boatsafe.com/nauticalknowhow/captpat1.htm


The image is just to get a picture of the forces at work, nothing else.

Moment arms and things........................

http://www.nmri.go.jp/eng/khirata/st...n/index_e.html

Why would a flattop deck automatically be more top heavy than a tall superstructure?

[kach22i]

Originally Posted by RatliffFranklin

Why would a flattop deck automatically be more top heavy than a tall superstructure?

Not this again.

When did I say that?

I think the idea of usable deck area to be an attractive one. Perhaps it's one of the attactions of Cat's and Tri's.

I'm kind of suprised at how little deck area some yatchs have, maybe it's the same as in architecture. I keep designing "transitional spaces" such as porches, but in our northern climate I seem to be fighting clients to keep them from completely enclosing them.

They know what a deck is for (somehow), but often even those get covered with awnings. I guess by the time you are old enough/rich enough to afford a yatch you don't want to be bitten by the wind and sun.

[Excalibur]

Originally Posted by kach22i

Not this again.
They know what a deck is for (somehow), but often even those get covered with awnings. I guess by the time you are old enough/rich enough to afford a yatch you don't want to be bitten by the wind and sun.

Ya, that's pretty much it. If you a maxi for marina sailing, decks are always too cold/hot/wet/dry/andthedarnedbirdsmakemenervous. There just aren't enough folk out there who are willing to give up "in" space for "out" space. A lot of times, this stuff is just market driven, and there is no other logical answer...

[charmc]

I can't find it now, but I saw a design recently for a large monohull sailing yacht with a deck wider than the hull. If I recall correctly, there was a sophisticated system for rapid transfer of water ballast to aid stability. It looked very cool. I can't remember the name of the designer, and searching all the relevant terms hasn't helped. If I ever find it again, I'll post a link.

In general, I'd guess that luxury yachts are nearly all built with tall superstructures because of a desire by owners for all areas to have a great view and at least the feeling of spaciousness. If you were to couple the tall superstructure with a wider deck, more of the budget would be eaten up by stability enhancers, with less left for luxurious fittings and the essential bringalong toys.

Dunno if that's the answer, but it might be one of them...

[kach22i]

I wonder if there is a golden ratio of sorts which a designer could use in designing a superstructure of proper width to height. A kind of "rule of thumb" so that expensive stability systems would not be needed.

I'm thinking that you could go a lot wider than taller before getting into trouble as "RatliffFranklin" first made observation of. Then again being located near the center of movement rather than on the extreem outside movment of a moment arm there must be a comfort factor involved. Kind of like you are better off in the middle of a boat/car than hanging off either end.

[charmc]

Originally Posted by kach22i

I wonder if there is a golden ratio of sorts which a designer could use in designing a superstructure of proper width to height. A kind of "rule of thumb" so that expensive stability systems would not be needed.

I'm thinking that you could go a lot wider than taller before getting into trouble as "RatliffFranklin" first made observation of.

Some of the new WallyDesign concepts appear to have deck sections aft which are wider than the waterline beam. Not exactly the flattop RF referred to, but still, a deck wider than the hull. Leave it to Wally to push the traditions. I notice their superstructures aren't exactly skyscrapers, either.

http://www.wally.com/jumpCh.asp?idUs...tStartRecord=4

[FAST FRED]

No matter how BIG it looks while standing on it , a carrier deck looks like a postage stamp from 300ft and a mile behind at the start of a landing.

All that's looked at is the "meatball" a white light between a set of green datum lights. If the meatball is high , you are high , if low you are low and perhaps about to die.Ramp Strike!

In the old days "meatball , lineup (with the deck centerline) and airspeed" was the mantra.

Today the auto pilot probably lands,40 years ago is a long time .

FF