[Rhodes22-list] Doyle UPS sail experience, helm balance, etc.

[The Rhodes 22 Email List]

Hi Ted,

Yes, I'm loving the Rhodes - fits all my criteria so beautifully.

I'm thinking the USP takes care of the low wind speed situations perfectly.
I'm really not sure how much faster you'll go with it vs a 130 in, say 3 or
4 mph wind but since, in my case, it's free, I'm sure going to find out.

So, I want my jib to take care of everything from 10 mph up to 20 or so.
Beyond that I'll just sail with the main. Once you reach hull speed what's
the point of more sail?

So, my quandary is whether to go with something around 100% so I can rig a
self tacking feature when I'm feeling lazy.  I figured 100% would give me
roughly 125 sq feet. The 175 is 200 sq feet - less than double the sail
area. 

Drive from a sail at a given wind speed is directly proportional to its
area. Drive from a sail of a given area is proportional to the square of
wind speed.  So 3 mph gives you 9*(sail area)*(a constant) and 10 mph gives
you 100* (sail area)*(a constant) . So you can see that wind speed quickly
becomes more important than sail area -  10 times more force at 10 mph vs 3
mph. 

At 10 mph wind, force on a 175 completely unfurled would be 100*(200 sq
ft)*(a constant) = 20,000*(a constant) and on a 100% would be 100*(125 sq
ft) * (a constant) = 12,500 * (a constant). Seems like that 12,500 whatevers
might be all the power I need to get near hull speed and the 20,000
whatevers would have you furling the 175.  

For 3 mph the numbers are 1,800 * (a constant) and 1,125 * (a constant)
respectively. 

I just worked through this for my own benefit - going on instinct
previously.  Glad to see numbers confirm instinct.  I reserve the right to
be wrong.

Remaining quandary is whether 100% should be hank on. I've been sailing a
San Juan 21 and got a sun brella deck sail bag for its jib so leave it
hooked to halyard,  hanked on and sheets attached, with bag zipped around
sail and fore stay. So to go sailing, unzip bag, yank it off, go back to
cockpit and raise jib when ready. About 30 seconds slower than with roller
furling. I have also rigged a line to pull down jib so I can douse it in
seconds. Yeah, stuffing it back in bag takes a few minutes. I've used this
for a while and has really reduced my sense of "needing" roller furling. A
plus: you get slightly cleaner airflow at luff.

 Brooks Bridges 
R22 1986/2006 
 Cambridge, MD 



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