Sail inventory

[LogoFreak]

Hi,

It's getting close to the time for me to have my boat measured for a new gennaker and I have a few options. Trying to have a good balance for various wind conditions. Does anyone know at what TWS will our boat achieve hull speed with a 135% Genoa? On a reach. I have the option of two different gennakers and don't want to go too big or too small, one is the helix gennaker and the other is the easy furling gennaker. The Helix can point higher while the easy furling gennaker can run deeper. Either sail can achieve similar angles but they're optimized differently, at least that's how I understand it.

[Gary Brockman]

I think it depends on what conditions you anticipate needing to use the sail in the most often. Are you going to be close/beam reaching or running more often? I have an A-3 (reacher) and an A-2 (runner) and I use the A-2 more often than i do the A-3. In light to moderate wind, I think you gain more impact with a runner than you do with a reacher. If the wind picks up, it's also harder to carry a reacher than a runner. Don't know if this helps, but i would go with the Easy furling gennaker.

[PaulJacobs]

Hi Gary,
First, regarding hull speed for a C34; from my experience Pleiades, in relatively flat water (viz. Narragansett Bay) with a properly trimmed 135% Genoa and a full (TR) mainsail will essentially reach hull speed in roughly 12-14 knots of true wind speed on a close reach (AWA = 70-80 degrees), about 14-15 knots on a beam reach (AWA = 90-100), and about 16-18 knots on a broad reach (AWA =120 - 130 degrees), assuming the hull is NOT surfing.
Second, I am having a hard time reading the plot you included.  I assume the abscissa is true wind speed (TWS) and the ordinate is true wind angle (TWA) although it might be apparent wind angle (AWA)?  I cannot read what the almost horizontal curves represent, nor the "quasi-parabolic" curves.  Please explain.
Third, I am really surprised that the operational domains for the two different sails (Helix and Easy Furling Genniker, or EFG) barely overlap - around 130 degrees TWA (or AWA?) from about 9 - 12 knots.  Assuming the plots are valid, then clearly the Helix is definitely intended for close reaching, beam reaching, and barely broad reaching, while the EFG is more like a traditional spinnaker, and is intended to be used mostly when broad reaching. 
Fourth, except in very light air (TWS<5 knots), or if racing, your C34 will move along nicely from 5 knots TWS up to about 18 knots when beating, close reaching, beam reaching and even broad reaching up to about 120 degrees AWA.  Beyond 130 degrees AWA things will slow down especially below 10 knots TWS.  It is this sailing domain where a genniker can really help.  Thus, I agree, if I intended to purchase only one genniker, I would go with the EFG.

Dr. Paul Jacobs
Pleiades
1990 MK 1.5 # 1068
TR, FK
Wickford, RI

[LogoFreak]

Thank you for the feedback guys! I'll try to the a better plot as this one is hard to see even for me.

[LogoFreak]

Decided to to with the Helix furling gennaker (710sq/ft), biggest consideration was that I can have it made with a UV strip. I plan on hoisting it at the marina before leaving for a weekend/week and taking it down when I return. Down the road if I find that I need a larger more downwind capable gennaker I will order the G2 (1065aq/ft).

Picture shows 3 options, smallest is the helix (torsion cable in the luff), then is the easy furling gennaker (torsion cable in the luff) and the last is the G2 (external torsion cable). They are all setup for top down furling.