A/B Ratio

[DanM]

Has anyone ever been privy to the A/B Ratio of the Carver 466? Any past Carver engineers on the forum?

TIA,
Dan

[km1125]

No idea.

But if you haven't already read this, then take a look:
https://northwestyachts.com/wp-content/ ... Seaton.pdf

and just a sample:

Now I own or have read almost every book on yacht design and naval architecture and
none of them, as far as I'm aware, mentions an A/B ratio……period. For naval architects,
there is no such thing as an A/B ratio. The reason for that, I believe, is that the A/B Ratio
neglects several areas of importance to the stability of a vessel. In a nutshell, the
following areas of design are what govern the stability of the vessel.
 The vertical and horizontal center of gravity
 Beam of the vessel
 The shape of the hull
 Tankage and location of same
 Non-watertight openings and where they are located.
These are just a few of the conditions that go into the calculations. The A/B ratio does not
consider any of these.

[DanM]

Hi KM, Thanks for sharing this. It's a very interesting read. It highlights the many issues in yacht design that are not absolutes and in some cases purely speculative as far as importance or accuracy. This is one I actually thought was a bit more defined, Lesson learned.

[bud37]

Source of the post Has anyone ever been privy to the A/B Ratio of the Carver 466? Any past Carver engineers on the forum?

TIA,
Dan

Okay , so I am curious now.....how did this come up ?

[Midnightsun]

I had to look it up. Now I know a Suzuki Samurai 4x4 had a poor A/B ratio.

◊A/B RATIO
A/B ratio measures the ratio of the side-view area of the
vessel above the water to the side-view area below the
water. For stability and sea-worthiness, this ratio should
be as small as possible, since more area above the water
means more area on which wind and waves can exert
pressure to capsize the vessel.
In practice, it's very difficult to build a yacht with an A/B
ratio below 2.0 with reasonably comfortable
accommodations. Once again, Beebe recommends an A/B
ratio of 2.6 or less for an ocean-going trawler.