Gennaker

[Theis]

For those of you that have been considering a gennaker, they are really the cat's meow - particularly if faced with sailing solo. I was fortunate to have someone catch this photo of Solsken last summer under its gennaker and thought it might be of interest.

[Mike Goodwin]

Theis,

What are the luff and foot dimensions on that rag, looks good ?

Mike

[Theis]

Those are good questions, Mike and I don't know. The dimension you give the sailmaker is the dimension of the forestay.

As you are likely aware, a gennaker technically is called something like an asymetrical triaxial spinnaker. All the dimensions are computer generated depending on several design factors, such as the as the desired angles of tack, and the design wind velocity. My gennaker goes downwing to about 165% design degrees and about 15 mph wind. Being a downwind sail, and not a reaching gennaker, it has particularly broad shoulders. Further confusing the dimension scene is that the square footage is of the gennaker is about the same as my number 1 genoa, but the square footage of the gennaker has nothing to do with the square footage of the gennaker. You read that right. My recollection is that the area of a gennaker is figured as the planar triangle. Take the straight line between the three points, and figure the area. The bulge, and the area outside the triangle are not part of the computation. As for the tack, It is longer than the forestay. So, summarizing, I don't have clue as to the answer to your question.

You may have noticed in the pic that the sheet runs to the stern of the boat, and at the top of the spar is the "sock" that makes bringing the puppy down a dream.

[Jim Wiles]

Theis,

Your gennaker really looks great! We fly one also and really enjoy it. Ours is our original spinnaker that was recut and we call it a flasher.

I have been wanting to meet you also since our Ariel, Mon'KeNe, #391 came from Racine. We bought her through brokerage at PJ's in 1980. The owner was a member of both RYC and Burnham (sp) Harbor YC Chicago. We have sailed her on Lake Shelbyville, Shelbyville, Illinois ever since. I hope sometime in the future to have an "eyeball" with you. If you are ever coming down to central Il. send me an email!

Jim

[Theis]

Jim:

Those fancy and expensive rags are fun, aren't they?

The only way we are going to get together is to set a date and time and, if it is up here, hope the Lake behaves itself. My email is theis@owc.net. You're about three hours from Racine, aren't you. Illinois is such a long state that, in terms of proximity, being in the same state means relatively little. I wonder if there are enough Ariel's/Commanders within a couple hours to have a rendezvous of some sort.

[Jim Wiles]

Theis,

You are correct that we are about 3 hrs. away from Racine; we get up to Racine a couple of times a year. In the future we look forward to bringing Mon'KeNe back to her earlier waters. As far as we know her first owner was in the Detroit area. A rendezvous certainly sounds like fun! When we are up on the lakes on charters I'll kind of keep a head count. We chartered a Catalina 38 last summer in Traverse City and I again saw both Ariels and Commanders there. My email is: kb9jlj@yahoo.com

Jim

[Theis]

If you are headed up here from time to time, that makes it easy for me. Let me know, even on the spur of the moment, and we'll head out - perhaps after a lunch at the Yardarm.

[Brendan Watson]

The gennaker set up looks pretty sweet. How does it tack on
the bow? Have you ever tried a spinnaker poled straight out over the bow?
Whats the difference sailing wise, besides the lack of pole, up-haul, down-haul and after-guy?

I dont have the spare boat bucks to order a new gennaker like the sporty one in the picture
but I do like sailing fast downwind and reaching. My low-budget solution was to get a
used, little if at all, J-24 symetrical spinnaker, ($100.00), and a broken Forespar 7'-17'
adjustable whisker pole out of a dumpster which I repaired. There already was an eye strap
on the mast for an up-haul block and the downhaul block is an old and perfect Shaefer
thats shackled to a webbing loop that wraps around the fore-deck cleat.
To make a cheap story short, with the pole extended to about 10' and held back about
9" from the forestay with the sheet hauled right in youy can just about go to weather in light air.
In heavier air I wouldn't mess around. For broad reaching the symetrical works better than
fine. As the air gets heavier, due to the deep cut and size of the chute, I tend to go more and more
down wind. With the GPS reading low to mid six'es with the dinghy jumping out of the water
I felt the time and money was well spent in adding the capability to my boat. As for the pole,
it bends a bit but with the three tubes inside each other is suprisingly strong. Another
thing about the symetrical chute is your ability to go dead downwind which the cruising chutes,
read asymetricals, dont do as well. Is this true of gennakers as well?
No matter how you do it moving the center of effort forward on my Commander has been an
eye opener. The boat develops alot of power with her nose down, throwing a wide bow-
wave with the chop smacking off the hull with a vengeance.

Cheers, B.
Commander #215

[Theis]

The gennaker tacks on the bow with a line (part of the gennaker) that passes through a block on the bow fitting. That line is then cleated to the bow cleat. In that way, the gennaker tack can be brought in or let out, depending on the air and the angle of tack. The other two points of conection are the top of the sock (not the gennaker), and the clew (and a separate sheet line is used leading to one of two blocks mounted on the stern deck, as far aft as possible. Only one sheet line is used ( two can be used but it is more trouble). If you need to tack, the sheet line is moved to the other side.)

I have not used a whisker pole with the gennaker because, assuming there is a breath of air, it holds itself out pretty well. Also, I generally try to avoid going directly downwind, the gennaker being good for anything from a close reach to almost downwind (165 degrees).

I do have a huge #1 genoa (170%) and do use a whisker pole for that because it does collapse, particularly when going wing and wing.

The problem with a spinnaker (as contrasted with a gennaker) is that the spinnaker pole is the problem, particularly when sailing solo. Getting that puppy down can be problematic. There is a lot of force compressed into that pole if the winds go the wrong way, and I fear it could bounce me off the foredeck if things went wrong.