Re: Digest Number 1850
> the "long boomed gaff rig", being a low aspect airfoil isGood point. I had not thought of that. I am more dubious about the
> less affected
> by changes in angle of attack..
advantages of a heavy boat with great momentum, however, based on my
racing experience.
Peter
The three factors mentioned by Bolger interact thusly to cope with the
motorboat wake: the "great momentum" keeps her moving through the
wave, the "deep, easy (lined) bow" cleanly slicing and smoothly lifting
to the wave (thereby imparting less abrupt motion to the boat), while
the "long boomed gaff rig", being a low aspect airfoil is less affected
by changes in angle of attack, and will therefore be more likely to not
lose its drive. The greater mass of the long boom and the gaff may
also contribute by slowing the motion of the sail, helping it to keep
the wind in.
Bob
---
motorboat wake: the "great momentum" keeps her moving through the
wave, the "deep, easy (lined) bow" cleanly slicing and smoothly lifting
to the wave (thereby imparting less abrupt motion to the boat), while
the "long boomed gaff rig", being a low aspect airfoil is less affected
by changes in angle of attack, and will therefore be more likely to not
lose its drive. The greater mass of the long boom and the gaff may
also contribute by slowing the motion of the sail, helping it to keep
the wind in.
Bob
---
> Message: 12
> Date: Wed, 14 Jan 2004 18:10:25 -0000
> From: "pvanderwaart" <pvanderw@...>
> Subject: Re: Which Box?
>
>> PCB writes: "...with her deep, easy bow,
>> great momentum, and longboomed gaff rig,
>> she's much better able to cope with the
>> plague of motorboat wakes in light weather
>> than lighter boats with more modern-looking
>> rigs"
>
> This is one of those PCB statements that takes a little thought to
> understand. In fact, I am not sure I do. My first reaction on
> thinking about the post was that having a long gaff and boom sent
> flailing about by a succession of wakes was not very conducive to
> forward progress or peace of mind. However, perhaps he is suggesting
> that as a gaff sloop, Monhegan has more sail area in her basic rig
> and is less dependent on light sails (i.e. spinnakers and reachers).
> Flying a spin from a bouncing boat in a breath of wind is tedious.
>
> Certainly one of the advantages of a complex hull shape over a box
> shape is less wetted surface, although I'm not sure that Monhegan is
> exemplary in that regard. Other boats to consider would be the
> plywood 12 1/2 and the Lynx catboat. I wonder if PCB ever considered
> a cuddy cabin version of Seabord '86.
>
> I was not sure what wind strength was part of the original picture.
> Perhaps light air is not a major consideration.
>
> Peter
>