Posted By: Wouter
F12 fundamental concept, a document - 11/12/07 02:39 PM
Dear interested readers.
At this time it is good to formalize the F12 concept, so that we all are on the same page and can coordinate all our efforts more closely to a single end goal.
Here is draft document that summerizes the setup that I have been working on for the last few years.
http://www.xs4all.nl/~whijink/F12/The_F12_catamaran_concept_draft_version.doc
At this time it is a draft version, as I have a little trouble getting my mind of the F12 design details and focus back on the big picture. So some changes may still be made to the document later on.
However I think the basic idea will be clear.
Now Retired Geek has shown us all that a multichine hull can look very attractively. The push rod setup as proposed by myself is proving itself more and more attractive in the way of construction and cost. Some parties has offered to do some prototyping. And the recent decision by ISAF has made the F12 project alot more important as we may well find ourself totally depending on our own soon.
I say we are on the good track to a succesful implementation of an F12 design. But indeed for us to proceed succesfully we'll need to make some difficult decisions. For example daggerboards will be in or out and once decided it will have to stay that way. And from then onwards everybody associated with the F12 project will need to accept and honour that decision.
I propose to settle these points and the basic F12 specs before X-mas.
With respect to the basic F12 specs I remind everyone that earlier we had more or less settled on :
overall length 3.750 mtr
overall width 2.000 mtr
overall mast length max 6.000 mtr.
overall sail area max 7.000 sq. mtr.
Overall max luff length 5.300 mtr
The latter two specs lead to an mainsail aspect ratio of 4 which is sufficiently high for good performance. F18 and F16 mainsails have a ratio of 4.25. The hobie wave of 3.40. The Moth are around 4.25 as well I believe. Hobie 14 mainsail has a ratio of 3.
I'm not looking forward to breaking this open, but if anybody feels the need to do so then now is the time to do it. If convincing arguments are given then we may well change these.
Wouter
At this time it is good to formalize the F12 concept, so that we all are on the same page and can coordinate all our efforts more closely to a single end goal.
Here is draft document that summerizes the setup that I have been working on for the last few years.
http:/
At this time it is a draft version, as I have a little trouble getting my mind of the F12 design details and focus back on the big picture. So some changes may still be made to the document later on.
However I think the basic idea will be clear.
Now Retired Geek has shown us all that a multichine hull can look very attractively. The push rod setup as proposed by myself is proving itself more and more attractive in the way of construction and cost. Some parties has offered to do some prototyping. And the recent decision by ISAF has made the F12 project alot more important as we may well find ourself totally depending on our own soon.
I say we are on the good track to a succesful implementation of an F12 design. But indeed for us to proceed succesfully we'll need to make some difficult decisions. For example daggerboards will be in or out and once decided it will have to stay that way. And from then onwards everybody associated with the F12 project will need to accept and honour that decision.
I propose to settle these points and the basic F12 specs before X-mas.
With respect to the basic F12 specs I remind everyone that earlier we had more or less settled on :
overall length 3.750 mtr
overall width 2.000 mtr
overall mast length max 6.000 mtr.
overall sail area max 7.000 sq. mtr.
Overall max luff length 5.300 mtr
The latter two specs lead to an mainsail aspect ratio of 4 which is sufficiently high for good performance. F18 and F16 mainsails have a ratio of 4.25. The hobie wave of 3.40. The Moth are around 4.25 as well I believe. Hobie 14 mainsail has a ratio of 3.
I'm not looking forward to breaking this open, but if anybody feels the need to do so then now is the time to do it. If convincing arguments are given then we may well change these.
Wouter