Why a pole for spinnaker?

[Mings74]

Hi all,
After my last play with the spinnaker in very light winds (<5 knots) I tried taking the pole down. Kite seemed to fly okay without it. Whats the benefit of using the pole?, was it easier because of the light winds?, quite often I don't have the main up with the kite, should I?. Cheers Ming

 

[nickdick]

Yes, a pole will be needed in higher winds and in lower winds if you want to do anything other than go downwind. If on that day you had say, 15 knots of wind without a spinnaker the sail would have a mind of it`s own and sway from side to side (innefficient) and frightening as it tends to take the boat over with it. The other rule is that with a pole to windward you can sail very fast with the wind 45 degrees or more forward of the beam with a good reaching sail - without a pole, only downwind as the spinnaker will just flap against the back of the mainsail. There are other benefits such as being able to release the windward clew from a fixed point on the bow when you want to get it off etc. Tip - you`ll need a pole to have more fun !

 

[rivonia]

Pole is realy only req'd on a mono hull we use spinnaker with no pole on our Catamaran and are able to move it around the boat when the the wind shifts.

 

[dt4134]

Sssshhh! Don't tell everyone.

It's amazing how many race crews get so worked up about the spinnaker pole.

 

[Refueler]

For years I flew Spinnakers without a pole as my father and others did. Later I graduated to a pole - but still no uphauls / downhauls. Today I am contemplating whether to rig them or not.

IMHo - lack of a pole means greater care in helming ... you have to keep that head spot on to hold the wind in the spinny .. which often means steering of the wind to be sure it's few degrees ahead of the 1/4 ... I get immense satisfaction getting a spinny to fly without the additions.

 

[Twister_Ken]

The power a big kite can develop is very considerable, damaging even. That's why you want as much control over it as possible. Having two corners fixed in space (tack and head) let's you keep the beast on a tight rein, and tune it to the exact wind angle and strength.

 

[tross]

Because it opens the throat of the spinnaker to the wind and allows you to control airflow over the sail - spinnakers still have a centre of effort which you can control with the pole and the down haul / up haul.

 

[Twister_Ken]

Tross makes a good point. There is a tendency to think of a spinny as a sort of parachute, creating motive force by blocking the wind. But they are not sacks, they are aerofoils, with laminar flow around both sides producing thrust. The pole allows the angle of attack of the foil to be set.

 

[William_H]

Hi Ken just to be correct a spin is a sack with wind right behind the boat and an airfoil with wind to the side.With variations between the 2. I spin a lot and always have a pole. It helps to get the spin out to windward away from the shadow of the main sail. And of course it is a lot more stable especially when most spin work is not square downwind. olewill

 

[Twister_Ken]

And just to semi-correct you, not if you're doing it properly it isn't! Going dead downwind, the act of squaring the pole right back and easing the sheet a long way allows you to present the luff as a leading edge, and generate lift on part of the sail, as well as drag on the rest.

 

[Aeolus_IV]

As other have said, the pole does four things for you:

1/ Allows you to "fix" two of the three corners of the sail making it easier the handle.
2/ Allows you to keep the leading / windward edge of the sail clear of other sails (keeping the pole perpendicular to the wind) which allows you use the spinnaker on points of sail other than down wind.
3/ Allows you to adjust the height of the foot of the sail (giving control over the shape and lift of the sail)
4/ Makes it easer to trim the sail

Should you keep the main up when flying a spinnaker? Yes, it gives you somewhere to "hide" the spinnaker when you wish to raise and drop it. The natural turbulence behind the main will often draw the spinnaker into the boat and make it easier to drop the sail (assuming you're not using a snuffer - which is another discussion).

I think (if I'm right) that you're in the main harbour, I'm just inside the north harbour. If you want a second opinion I could saunter over on day.

Regards,
Jeff.