I had an interesting event in our
Lagoon 46 that I thought I’d share.
I’m not inexperienced, but not an old
salt either. (old, just not that salty!) Most of my experience has been in mono’s years ago, but we've moved to a cat and I’m still
learning the ins and outs of cruising cat performance.
We were on a broad reach, starboard tack, AWA about 130-135. Winds were steady about 15 knots.
Boat speed about 5-6 knots. Comfy. Quiet. Lulled into a sunny day not-a-care-in-the-world mood. Full main, no
jib. (I know some people will stop reading here and say “well, that was your problem,” and they are probably right. More on that in a minute.) At the time, it felt like the self-tacking
jib was flailing a little too much and not contributing to our forward motion, so I just furled it.
Comes time to Gybe. I sheet in the main and throw the
helm over to port. We pass through the
wind and the main fills on the new port tack. I spin the
helm almost full to starboard and…nothing. The
boat keeps turning to port. In a matter of what seemed like about 8 seconds, we rounded from a port tack broad reach to being close-hauled and heading on about a 70 AWA.
At this point in time, I settled on the close haul for about a minute to gather my thoughts, then deployed full jib, and tacked to a starboard tack letting the boat go all the way to a broad reach and settled in there while I thought about what just happened. Luckily, we had plenty of room and the gybe was more to stay on course than any obstacle avoidance.
I finally bore away again to our original broad reach. Later when I decided to gybe again, the gybe went as I would have expected, and we went from about a +130 AWA to about a -130 AWA.
I am taking this as a
learning episode and welcome anyone’s thoughtful input on what happened.
My thoughts:
First: Unbalanced
sails. Even if the jib is not doing a lot, it is there to balance the boat, especially when changing points of sail. I am now paying a lot more attention to how much helm I’m using and paying attention more to my sail plan and its balance, not just in the
current configuration, but in any configuration that may come up. I think the boat settled in at the 70 AWA because the sheeting of the main was such that it was depowered enough at that angle to stop the turn while adding enough forward vector to gather speed and give us more
rudder authority.
Second: The
Lagoon 46
mast has been moved aft from other designs. This puts the
mast almost squarely in the center of the boat. That means that rotational torque has a greater effect than if it were off center. This allowed the
wind to force the boat around regardless of
rudder position. Again, sail balance was off. A jib would have countered this torque with a nice counter force on a long arm from the mast, as it did during the second gybe.
Third: at 5-6 knots there isn’t a huge amount of rudder authority, and certainly not enough to overcome the torque of the main by itself. There is a lot of
power in that main!
What are your thoughts? Am I missing anything? This quick event was both surprising and humbling. It took me a while to figure out what I think happened, but like I said, I'm open to other's insights as well.
This does have me thinking though about heaving to in the cat with a self-tacking jib. While some claim that you should secure the clew to windward before tacking, others have claimed that it can be done on a cat without the jib and counter helm after tacking. After this experience, I think that might be possible, to an extent, but the sheeting on the main needs to be just right or it will overpower the helm. This seems like a good afternoon of trial and error one weekend…