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D.2.2.b confusion

Posted: 13 Dec 2010, 15:35
by Andy Ashwood
Hi All,

Im trying to penetrate the wording of D.2.2 b at the moment and failing (it could definitly use a little clarification in my opinion) so I thought I would just post my question here:

Assuming that all the dimensions adhere to the IOM rules and just considering the shape, does the hull shadow below contravene D.2.2 b (or any other rule) and if so, why?


Re: D.2.2.b confusion

Posted: 15 Dec 2010, 09:54
by Andy Ashwood
Seems like nobody else understands D.2.2.b either :?

Lets see if we can dissect the wording then:

Construction is unrestricted subject to the following:
(a) The hull shall be a monohull.
(b) Except for trunking for the keel and rudder, the hull shall not have:
(1) voids in the waterplane and/or the underwater profile,
(2) hollows in the plan view and/or the underwater profile that exceed 3 mm,
(3) transverse hollows in the undersurface of the hull that exceed 3 mm when tested parallel to the waterplane as in figure H.2.


1> "waterplane" and "underwater profile" are the "at rest" versions, not all possible versions between upright, heeled over and capsized.
2> A "void" is basically a piece of the hull missing
3> Plan view is the view from above

So, D.2.2.b.1 means "You cannot have any holes in your hull"
D.2.2.b.2 means "The hull shall follow a smooth curve from bow to stern"
D.2.2.b.3 is pretty well explained by diagram H.2 (maybe there should be diagrams for the other two clauses)

Can anybody confirm my interpretation of these clauses?

Andy (amateur builder)

Re: D.2.2.b confusion

Posted: 15 Dec 2010, 17:33
by Lester
Hi Andy

As far as I can see, your cross-section doesn't fall foul of the D.2.2 rule!

Re: D.2.2.b confusion

Posted: 15 Dec 2010, 17:37
by Andy Ashwood
Thank Lester!

That gives me the confidence to start a build :)