Racing Downwind - Crew Position

[Ducati]

Back when I crewed on a 41'-2-ton we were always asked to move to the back of the boat when going down wind. (spinnaker up of course)

I never questioned it but today I would like to know why.

Thanks

 

[Raisin56]

Most spinnakers have about the same sail area as the main and Genoa combined. with all that force pulling at the top of the mast or near it (fractional rig) the leverage wants to pull the stern up and bury the bow in the water. Moving crew aft helps counteract that force.

 

[Rick D]

To Digress...

...I had an interesting conversation with one of the crew of a large ocean racer in the Fastnet 1979 race. He said the crew ran fore and aft under bare poles for eight hours to keep from pitchpoling or broaching. He said they were ready to collapse but for the terror.

 

[Rick Sylvester]

I dunno Rick,

I'm not sure I'd want the increased likelihood for a COB. On a big boat in a dangerous seaway I don't think it'd have much affect. I doubt they could move quickly enough anyway.

Broaching or pitchpoling? That's all about the hand on the wheel.

What do you think?

 

[PaulK]

Your saying you were on a 2-tonner brings to mind the typical IOR designs of the '70's. They were frequently designed with wierd hull shapes, designed to fool the rule into considering them as slower than they actually were. Flat hull sections forward were typical, very narrow bows, very wide maximum beams (to lever the crew weight outboard going upwind) and pinched sterns. This made for very squirrelly behavior going downwind, with lots of boats spinning out, rounding up, and broaching, especially when racing with more sail up than might otherwise be advised. Your skipper may have wanted crew weight aft downwind for a number of reasons: 1/wetted surface. Getting the long, narrow bow out of the water would reduce wetted surface and thus increase speed. 2/ Submarining. The long, narrow bow doesn't tend to provide much lift to get the boat over waves - it cuts right into them instead. Burying the bow is slow- it adds to wetted surface, and if the water comes up over the deck, the water's weight slows the boat down too. Water washing down the deck can take crew with it, and if the hatches aren't properly dogged, it goes below, where it's weight continues to slow the boat until it's pumped out. I believe J/24's require their forward hatches to be closed while racing because of this. I know of one that submarined in a race and is still out there under some 60' of water in Long Island Sound. 3/Rudder immersion. Boat rudders don't work out of the water or if water isn't flowing smoothly over them. The funky shapes mentioned earlier can do things to help make the water flow over the rudder's surfaces to be turbulent instead of smooth. IOR designs sometimes included skegs to help this problem. With the hull shapes making the boats tend to broach, which puts the rudder either into the turbulent top part of the water or out the the water entirely, keeping the rudder in the water, and (for efficiency) as deep as possible becomes important. Weighting the stern down helps keep the rudder in the water, so you can steer. Overall, IOR boats are (were) not that easy to sail.

 

[catsailor]

I posted a rather dramatic photo here, or a big boat digging in with a chute up.
http://sail-delmarva.blogspot.com/2010/04/merits-of-learning-to-sail-on-small.html

Also you-tube is always fun; search spinnaker and pitch-pole.

It really depends on the boat, the seastate, and the speed (once the boat reaches ~ 9 knots the water tends to leave the transom clean even if it is immersed a bit).

 

[Richard Bryer]

Your point about IOR boats and their behavior under spinnaker are certainly true Paul. I have raced a SJ24 for 15+ years and there have been nights when we were dragged all over the lake. We find that we have to have most weight near the back but enough weight at about the mast ( where coincidentally the best view is for flying the chute) to keep the narrow bow in the water enough to make the boat track straight ahead rather than swing to the lee side with the pulling of the chute. Gets very interesting if there are leftover waves from the beam with gusty winds!!

 

[Rick D]

I'm not sure I'd want the increased likelihood for a COB. On a big boat in a dangerous seaway I don't think it'd have much affect. I doubt they could move quickly enough anyway.

Broaching or pitchpoling? That's all about the hand on the wheel.

What do you think?

I really don't know, Rick. I do know that he is an Olympian sailor as are his two kids. What he also told me is that they could not turn around to go back for a boat in distress because the skipper said it would be suicidal to try (a decision for which they were criticized greatly). Considering he was crew, not the skipper, it may be that he was just following orders and what they may have had little effect on the boat's stability. I don't doubt the crew was all over the boat. I just don't know other that IOR boats were squirrely and we all know what the sea state was there.

 

[Rick Sylvester]

Oh yeah,

I certainly didn't mean to impugn your friend, I was just sorta thinking out loud.

I wasn't there and I'm sure it was a hairy ride. I think I read the book. Was it Force Ten?

 

[Alan]

I remember racing a Viper 640 with a make-shift crew that had never sailed one before. As the spinnaker went up I reminded everyone to get to the back of the boat as soon as the boat started to accelerate. They didn't move fast enough and the bow began the bury in the first wave as water rushed over all of us. The next time they were ready and the boat took off with everyone sitting at the stern rail. The keel started to hum as we past 15 knots. We pushed past 20 knots in no time. What a rush!

 

[Rick D]

Re: Oh yeah,

I think it was Fastnet Force Ten. I loaned it to someone years ago and it never rematerialized. I might get it on Kindle again.

 

[rpwillia]

Spinnaker Fun

On very good racer here on the Potomac River told me about one time they were flying the spinnaker in a race and got hit with a wind shift that buried the bow and then spun the boat around 180 on it's nose. Said it happened so fast all they could do was hand on.

On another boat I was racing with we got hit with a gust and a shift with the spinnaker and it broke the dyneema down haul line. That was pretty interesting.

 

[Ed A]

The fastnet force 10 book is awsome it really says alot about all the poor job most of us do in preparing for the big one.
Most of those boats were really equipped well. they had harnesses break mast fall, lifeline teathers break thru the boats. lots of boats broached. It is a facinating insite in to our sport. I think a must read for offshore races and cruisers. I lent my first copy, i wont lend my second!

 

[Ed Schenck]

Never read it. Just checked the library and they have "Fastnet, Force 10" and also this one:
Left for Dead: Surviving the Deadliest Storm in Modern Sailing History . Had them both Held.

 

[Rick D]

Read the second one as well (Left For Dead). The left for dead book is riveting reading, but his side of what happened is a bit different than other survivor's versions. Having said that, I am in no position to speculate on what this guy went through. If it were me, I would read Fastnet Force 10 first for a basis and then Left For Dead. Both are quick reads.

 

[Ducati]

Thanks For Your Feedback

Considering he was crew, not the skipper, it may be that he was just following orders and what they may have had little effect on the boat's stability. I don't doubt the crew was all over the boat. I just don't know other that IOR boats were squirrelly and we all know what the sea state was there. [/B][/COLOR][/QUOTE]

Not sure what is meant by a 2-ton having erratic or "squirrely" characteristics. I will do more reading about these boats however the vessel I rode on (Peterson) was rock solid. We did long distance big water races sometimes with 10"-12" following seas and we never had any fear of losing control. We all took our turns at the helm and it was like driving a freight train. Common sense always prevailed particulairy in big water conditions and when that was the case no one was ever running to the back of the boat to I assume keep the nose up. Anyhow, not sure how this turned into another Perfect Storm-Fastnet-We're all gonna die at sea discussion, but thanks to those who were able focus and stay on topic.

 

[Rick Sylvester]

It's Rick D's fault

Anyhow, not sure how this turned into another Perfect Storm-Fastnet-We're all gonna die at sea discussion, but thanks to those who were able focus and stay on topic.

HE started it. Wait, what were we talking about?

 

[Rick D]

It Was I