Subject: Re: [harryproa] Re: Rig questions, again
From: Gardner Pomper
Date: 1/3/2010, 9:25 PM
To: harryproa@yahoogroups.com.au
Reply-to:
harryproa@yahoogroups.com.au

 

It seems like the only time that you would have turbulent air on the 2nd mast would be when you are really, really hard on the wind and the booms are directly over the lw hull. As soon as you ease them at all, you would have plenty of separation for the airflow.


In my current design, there would only be 12' between the masts, so I could have a 4' jib boom and a 7.5' main boom, so they clear each other. I assume that I can make the mainsail on an easyrig just as big as a unarig, so I get the extra jib sail area for free, don't I ?

Also, I end up with an extremely high aspect ratio for my sails. With a 34' luff and a 7.5' boom and an 80% roach, I have 200 sq ft, for an aspect ratio of 5.0. I am not sure how comfortable I am with that. I saw a posting with a graph from Marcaj that showed an AR 6 sail providing max lift at a 10 degree apparent wind angle (which is good), but it falls off dramatically at 15 degrees, so it seems that it might be extremely twitchy to sail in real iife.

- Gardner

On Sun, Jan 3, 2010 at 9:52 AM, Mike Crawford <jmichael@gwi.net> wrote:
 


  I'd love to see a schooner easyrig.  But I'm not sure you'd get the clean air you'd want for that second jib unless you make the lw hull longer for more separation between masts.  The wing mast leading edges of a schooner una will be more tolerant of a bit of turbulence than jibs.  Plus, all the una sail is behind that mast, so if you have a large roach or flattop main, you'll probably get more sail area from a schooner una.

  But a schooner easyrig is definitely something I'd like to see someone else try.  I want one, but not badly enough to fund the experiment on my own.  If only Todd were still in the group with those beautiful models he could build and test...

       - Mike



 
Gardner Pomper wrote:
 
One question I did have from Mike's explanation is : why not use 2 easyrigs in a schooner? That would give the ease of handling of the easyrig, along with the redudancy and ease of steering of a schooner. In my case, particularly, it would probably give enough extra sail area to avoid 2 part masts and keep the low heeling moment of a schooner rig.

- Gardner



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