first time i read judy's post i got confused for a second and thought ... WOW that reads like a lot of sail on an M15.  a second reading i saw that there is a 'boat being discussed' change between the first and second paragraphs. i use the word 'about' as each loft will cut the sail just a bit differently. M15 has about 122 sq.ft. of sail in the 'working' configuration (full main and 128% jib). a jerry M17 has about 151 sq.ft. based on judy's report (or 154 sq ft on jerry's brochure) in 'working' configuration (full main and 100% jib) remember that the M15 is really 'powered' by the main.  put two reefs in the main before going to a storm jib.  don't luff the main on the M15 ... she doesn't handle this well because of her lack of a backstay. it is no fun doing a headsail change on an M15 when the seas and wind have increased.  keep in mind before leaving the dock and you 'think' you may need the storm jib.  best to go out and change to a larger jib in seas and wind that are decreasing. the M15 will sail well with a double reefed main and a 128% jib just above 20kts of wind.  in my opinion the M15 will not sail well to weather under jib or main alone ... you need both sails pulling! :: Dave Scobie :: former M15 owner - www.freewebs.com/m15-named-scred :: M17 #375 SWEET PEA - www.m17-375.webs.com :: Sage Marine - www.sagemarine.com --- On Thu, 3/29/12, Judith Blumhorst, DC <drjudyb@blumhorst.com> wrote:

Nope.  The 128% goes on the M15, Jerry's rig dimensions and sailplan works out to 151 square feet with a (theoretical) 100% jib.  His plans for the M17 show:

170% with a luff of 22.42 (about 95-ish percent of max forestay length)  150% with a luff of 22.42'  (the luff would have to be a little shorter for use on a roller furler.) 109% with a luff of 21.5' 80% with a luff of 19.25' 60% with a luff of 12'

However, Bob Eeg has given me slightly different dimensions for his M17 rig so the sails are dimensioned ever so slightly differently.   Bob's changes to the rig works means it pencils out at 148 sf.    The most significant difference is that his OEM 109% jibs are about a foot shorter on the luff. 

Judy Blumhorst Hyde Sails of Northern California www.judybsails.com   judy@judybsails.com

cell: 925.208.1692 fax: 925.820.2327 skype: judith.blumhorst www.HydeSails.com/NorthAmerica  

________________________________   From: Jeffrey Johnston <frjeff@gmail.com> Sent: Thursday, March 29, 2012 5:43 PM   Is the storm jib the 80%? And the "working jib" the 128%?

Jeff