The Finicky Genoa

Last night we came up against the precise finickiness of the genoa, our biggest upwind jib. It is masthead height, tacks to the bow, and trims through the ring along with the solent and staysail. Our polars say that upwind it is good to about 13 knots true wind speed. But actually, at that windspeed, the boat is completely overpowered with the sail. What works at 10 knots TWS, is actually then overpowered at 11kts TWS, and I spent the night (see the sleep data!) constantly easing the traveller, pulling it back in, filling ballast tanks 2 and 3, then emptying them, then easing the mainsheet for a bit more aerodynamic twist to the mainsail way up there at the top to ease the heeling, then in a light spot of 9 knots TWS, the boat stands upright, so if a tank is full, it must be emptied, which it doesn’t want to do because the boat isn’t heeling, so then you have to ease the 40 degree keel cant to 20 degrees. And of course immediately after doing that, the extra knot of breeze comes back, so you have to re-cant the keel, which takes 100 amps for about a minute. I would try to come back below and lay down for a 20 minute nap, but then the boat would lay over, and I’d have to go relieve the pressure, or the boat would stand up straight, and I’d have to go put on some more power.

That particular sail, the genoa, is this most finicky. The solent, in the same wind conditions, will happily pull the boat along, and will occasionally give higher speeds than the genoa, but in our game of data, our programs call for the genoa, so I unrolled that sail. What it really needs is to not be sailing close-hauled upwind, but for the boat to be angled off about 10 degrees or more. Then that genoa comes to play.

The stars were out in full force last evening, and I had hoped to be able to open H.A. Rey’s The Stars, my favorite star book because it tells the mythology behind the constellations, but unfortunately, this finickiness with the genoa prevented such a pleasure. Perhaps tonight!

Position
16° 17’S x 26° 37’W
Course
124° True
Speed
11.6 knots
True Wind Speed
10.0 knots
True Wind Direction
019°
Sail Plan
Genoa plus full mainsail
Air temperature
84° F / 28.8° C
Sea Temperature
84° F / 28.8° C