Downwind without a whisker pole... and: Parasailor?

[Pete the Cat]

I will keep an eye out for something cheaper, but Forespar has one listed as right for an E34 that is 10-18 feet long (part # 401106, telescoping; oddly they do not list specs, but fisheriessupply does, along with the 17# weight and 2"/2.5" ODs) I see from Forespar, though, that they suggest for a whisker pole having the( max genoa % * the J length.... there's math again...), which for my boat is 130% * 15 ft. That suggests I need a 20' pole... not the 18 listed (which may assume nothing bigger than 120%, or maybe an E34 instead of a 34-2 with longer J), but a size up. The need for a larger size seems even more likely if I ever got a big drifter (150-ish?) or asymmetrical. But then the larger pole is also heavier... so I ask you:

--> Pole length for E34: Any suggestions as to the correct max extension for a whisker-pole for an E34-2? Is 18' enough, even with a 130% genoa? 150% drifter or asymmetrical?

--> Topping lift: For rigging the pole, I understand I'll need a topping lift, though it is tempting to use the spare jib halyward for that... is that a bad idea? I.e., do I need to add one? T here is not a sheave/panel/etc for it already.

--> Pole downhaul: is this necessary for a whisker pole, or just for spinnaker poles (where the sail tacks/clews are free)? My E34 has no convenient place to attach something like that (toerail is not drilled, nor even metal), so unless necessary my enthusiasm for deck mounted additions is low.

Anyway, knowing the right pole size is obviously step one in trying to find a used one

Many thanks!

Here are my .02 cents on your questions. Much of this is personal preference and the kind of sailing you anticipate
1. Pole length: I am personally not a big promoter of large jibs and sail in SF Bay and Maine (I have boats in both places). I suppose if you need a 135% to sail in your area (like SoCal) things will be different, but I use a 125% in Maine and a 95% in SF Bay and find them appropriate--I will likely go down to a 110% in Maine next time--the tiny fraction of additional speed downwind is not worth the chafe and noise. I really do not like longer poles than are absolutely necessary either. I had an adjustable aluminum pole that came with the Tartan 37 that I finally dumped (weighed way too much for me to manage on a pitching deck) for a CF spinnaker pole that was actually a foot shorter than J. The reason was that I was cruising downwind for a couple years and needed to gybe the jib. Nice to be able to ease the guy forward to the headstay and then easiy dip the pole and reconnect on the new gybe--found I could do this and reef the jib a bit as well to moderate the rolling. On my Ericson 32, the aluminum spinnaker pole is about 6" shorter than J with my 95%. A short pole also makes managing things easier when you can roll the jib up and reach the jaws with the pole attached. Makes taking down the pole and storing it less of a balancing act when things get snotty.
2. Topping life: You could probably use a halyard for a topping lift, but that might really chafe the line at the sheave and is likely to make a mess of your halyard leads. Installing a block in the right place on the mast and running an exterior lift line seems like a much better and not very expensive idea--you are going to have to secure the lift line when you are not using it, so adding the other end and running it all outside of the mast is not the end of the world.
3. Downhaul; You are also going to need some sort of down haul imho because the pole (particularly with large genoas and rolly seas) could sky on you. I note that folks run whisker poles without a downhaul in calm conditions, but if you are going offshore I think the pole should be rigged for proper topping lift and downhaul for safety reasons. If the wind comes up and the boat starts rolling, you will dearly wish you had control before going forward.
I fly spinnakers regularly with these shorter poles and really cannot imagine that I would get better performance out of the chute with a few inches more in length, but racers are racers. In my racing days, I crewed for grossly overweight owner sailors who made us weigh our sea bags for ocean races. So it depends on your preferences and experience.
I prefer spinnaker poles with two bridles to some of the cheap whisker poles that just push the sail out in light air.
FWIW.

 

[bgary]

The question seems to be, can you make your boat go 15 percent faster when sailing 33 degrees off the DDW course. That would be 5.75 knots vs 5 knots, for example.

Short answer: yes. DDW is almost always slower than broad reaching. The question is, which wind angle provides the best ratio of increased speed against increased distance.

Longer answer: the polar diagram for a boat will show which downwind angle(s) are optimal. Polars will be different for every design, but even heavy displacement boats will have polars that show a bulge off to the side of the DDW vector, indicating an angle where the net speed-made good in a downwind direction is better than sailing DDW.

As an example:



The yellow line indicates what the speeds will be for this (example) boat in 20 knots of breeze. It shows that sailing DDW, the boat should go about 11 knots. But it shows two other things

-- at a wind-angle of about 130 degrees, the boat will be going fast, but ...the wrong direction

-- at a wind angle of about 150-160 degrees, the boat will not be going as fast through the water, but will be the angle at which the boat is netting out in the downwind direction (a horizontal line that just touches the polar curve shows where the best mix of speed and downwind course-made-good occurs)

Listening to on-board audio from (e.g., TP-52s in the Med Cup) you'll sometimes hear the tactician say "you're too fast". Tacticians often reduce polars to a set of targets; e.g. in 20 knots of breeze, headed to a downwind mark, the optimal angle implies an optimal boatspeed. If they're going "too fast", that means they're sailing too high an angle, and although boatspeed feels great, they're getting it at the cost of extra distance. Similar for sailing upwind. "too fast" means they're sailing too low and should come up to the optimal upwind angle.... even though it's slower through the water, it's faster to the mark.

Polars are not cheap to get (generally requires having someone model the boat in a computer and run the model through a velocity-prediction program). But one can get fairly close over time on their own just by keeping track of which angles produced good speed *and* good progress (course made good).

$.02

 

[nukey99]

Is the polar you have attached above for your Ericson 32-3, if so, I would be comfortable to use that as a baseline for our Ericson 35-3. Great illustration and explanation, thanks for posting it.

 

[bgary]

Is the polar you have attached above for your Ericson 32-3

No, I am not aware of one for the 32-3. Would love to find one. Somewhere on the forums I think someone said they got one (35-3? 38? not sure) as part of their package for an ORC rating. Worth a search.

(and, no, that polar is for a Volvo-60. Pretty sure my boat has never gone 20 knots downwind...)

 

[ConchyDug]

At around 16kt TWS the Ericson hull form likes DDW. You're just carving a bigger trench in the ocean at that point. Carrying the A-kite that low in 20kts is another matter though, you'll probably need new underwear. I included the polar for a 38 with a 16kt TWS crossover range for the headsail and spinnaker. The spinnaker is faster by fractions of a knot at the that wind speed. Best performance(VMG)is indicated by the tiny circles. To me the juice isn't worth the squeeze beyond 16kts to carry a kite. The shoal keel definitely adds to the squirrelly-ness of flying a 1200sqft kite. I also included 10kt TWS crossover to show how much difference a kite makes in the lighter stuff. I don't use a sprit the tackline goes thru a frictionless ring I lashed on the anchor bail and runs back to a clutch by the cockpit.