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RobGallagher 11-04-2011 11:11 PM

What happens if...
 
Something strange happened Thursday afternoon while sailing in Fisher's Island Sound.

Close hauled with the current we where having a great time in 25 - 30 knots of wind.

C&C 30 MK1, full main, 135 jib rolled up a couple of turns to maybe 130??

Passed by an area that gets shallow, so, wind against the current + shallow water = steep chop.

At the same time the wind seemed to really gust higher.

Something strange happened at this time, the boat heeled over further than I think she ever has. Close to a knock down with rail buried DEEP in the water.

The boat appeared to stall or slow considerably and the rudder felt like it locked up. I could not steer much at all.

I luffed, furled the jib and tried to fall of to gain a bit of speed under just the mainsail.

Still did not appear to gain speed, felt stalled. I though lobster pot? (Shallower water/rocks in New England = more pots. Did I snag one?)

I looked over the stern and though I saw a what could have been a line but there was so much turbulence coming off the rudder I could not be sure.

Looking forward to check my heading and sail trim I was about to as my girlfriend to go below and grab the line cutter. I checked over the stern one more time and could not see anything and it appeared some of the turbulence was gone. At the same time we picked up a little speed and off we went.

Note: We where only out for a short sail in familiar waters so I didn't bother turning on any electronics. I have no idea about speed over ground or through the water.

So after all that information, my question is:
Would a lobster pot line around the rudder while close hauled with a bit too much sail up cause the boat to come close to a knock down situation? I don't think we ever completely stopped so I'm not sure if we would have rounded down or what...??
If not, any idea what happened?

In 10 yrs of sailing the boat I've never come that close to losing control. C&C 30 MK1's are notoriously stiff beasts and I was having a blast up until that time. In fact, I've had more sail up in heavier winds with less drastic effects.

Sailormon6 11-05-2011 08:53 AM

We can't know for sure what happened. We can only give you our best guess. Mine is that the boat was overpowered by the wind and too much sail area while trying to beat to windward, and she was laboring. Here's your description of what happened: "...the boat heeled over further than I think she ever has. Close to a knock down with rail buried DEEP in the water. The boat appeared to stall or slow considerably and the rudder felt like it locked up. I could not steer much at all." In my opinion, excessive heeling caused an increase in drag, and that, along with the wave chop, gradually reduced her speed. As she gradually lost speed, she gradually lost lift over the surfaces of the keel and rudder, and at some point, her aerodynamic and hydrodynamic surfaces (the keel, rudder and sails) stalled. As she lost speed, you had to turn the wheel or tiller even more to keep her head to windward, and the effect of applying hard rudder was like applying the brakes, slowing her even more.

You said, " I've had more sail up in heavier winds with less drastic effects." On those other occasions, you might not have encountered as much chop, or you might have had the sails trimmed a little better, or your underwater surfaces might have been a little cleaner and smoother. A slight difference in the conditions can result in a very different result. I think it would not have happened if you had tucked in a single reef and rolled up a little more jib.

Of course, it could have been a lobster pot, but from your description, I don't think so.

sawingknots 11-05-2011 09:25 AM

maybe you touched the bottem and the the momentum[sic] of the boat carried it over and past

RobGallagher 11-05-2011 10:14 AM

Thanks for your replies. And thanks for reading that long winded description of what happened :)

@Sailorman, Good assessment. The only thing is, when I looked over the stern I could see that the rudder was near center but would not turn.

@sawingknots, could not have touched bottom, I was close to a shallow area but well outside the buoy.

Faster 11-05-2011 11:12 AM

Tiller or wheel? Could something in the lazarette have tumbled in the knockdown and blocked the steering system? and it fell free once you righted?

RobGallagher 11-05-2011 09:18 PM

Quote:

Originally Posted by Faster (Post 793861)
Tiller or wheel? Could something in the lazarette have tumbled in the knockdown and blocked the steering system? and it fell free once you righted?

hmmm.... Never thought of that. Will have a look tomorrow.

paulk 11-06-2011 11:03 AM

We have a friend whose steering gear "locked up" on him. Seems he forgot he'd turned on the autopilot...

WDS123 11-06-2011 12:36 PM

Good idea to ease the sails and head down.


My guess is that your loss of rudder control was due to the rudder ending up in a hydrodynamic state of 'chaos' - either cavitation, out of the water, or heeled over enough for rudder to be 'near horizontal' ; all might cause temporary loss of rudder.

I am betting that the rudder was partially out of the water and at an angle far from vertical.

Ascalon 11-07-2011 02:37 AM

Quote:

Originally Posted by Sailormon6 (Post 793836)
We can't know for sure what happened. We can only give you our best guess. Mine is that the boat was overpowered by the wind and too much sail area while trying to beat to windward, and she was laboring. Here's your description of what happened: "...the boat heeled over further than I think she ever has. Close to a knock down with rail buried DEEP in the water. The boat appeared to stall or slow considerably and the rudder felt like it locked up. I could not steer much at all." In my opinion, excessive heeling caused an increase in drag, and that, along with the wave chop, gradually reduced her speed. As she gradually lost speed, she gradually lost lift over the surfaces of the keel and rudder, and at some point, her aerodynamic and hydrodynamic surfaces (the keel, rudder and sails) stalled. As she lost speed, you had to turn the wheel or tiller even more to keep her head to windward, and the effect of applying hard rudder was like applying the brakes, slowing her even more.

I would endorse this as the most likely explanation.

I also note that your first action to shorten sail was to furl the jib. In boats with rolling furlers I know this is the most tempting option when having to shorten sail, but it's not always the best. In my experience, on a lot of broad-beamed cruising yachts the headsail is extremely vital to pointing ability under heavy conditions.

I think that by doing so you exacerbated already heavy weather helm and is perhaps part of the reason why you experienced such a delayed recovery.

In such conditions, by all means take in some headsail - but leave yourself something to work with, and don't be afraid to reef the main if you're overpowered. On big ponderous boats, generally the improved control gained by leaving some headsail out is well worth the extra canvas.

RobGallagher 11-14-2011 09:49 AM

Thanks for the well thought out replies.


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