Weather helm varies by wind speed

-- Last Updated: Oct-04-07 10:05 AM EST --

I was out at Skamokawa, WA, last weekend for the OOPS (Oregon Ocean Paddling Society) camp out and BBQ. Paddling my Tempest 170.

Participated in a wind and waves strokes class on Saturday afternoon. Maybe 10 knots breeze. 2 ft waves. On the crossing, beam wind and waves, I experienced strong weather cocking as usual in those conditions. Real PITA. Another T170 paddler said they experience the same thing.

Then Sunday I was at Ilwaco (down the street 30 miles), for the rough water rescues class. 20 knots wind, building to 30+. 2-3 ft waves. The Tempest was incredibly wind neutral at the higher wind speed. Extreme luxury! No problem staying on any course without the skeg. With the skeg down, I could get it where a slight adjustment of the slider would put me on a heading slightly windward. A slight adjustment the other way, slightly leeward. It was great!

Others commented that they felt some lee cocking as the wind picked up. I swam for the last rescue so paddled the couple miles back to the put in with a couple inches of water in my cockpit. That might have been lucky as that should further prevent lee cocking. Of course the bit of sloshing and momentum in beam waves was the down side.

An experienced paddler, paddling an Explorer, had put a couple water jugs in the bow compartment. I asked him after the trip if that was to prevent lee cocking. He said he hadn't been paddling the Explorer for that long and wanted to make sure the bow got enough bite in the water. I didn't pursue it and am still not sure of the exact intended purpose; to prevent lee cocking, less bob in the water, some other effect?

Do you experience a change in weather helm with wind speed in your kayak? Do you trim differently for expected high winds versus moderate winds?

Paul

Yes to both
Weather cocking is caused by imbalance of aerodynamic drag on the hull above the waterline and hydrodynamic drag below the water line.



The hull will weathercock until the imbalance is canceled.



Since both aerodynamic and hydrodynamic drag vary with the square of speed, it is expected that the strength of weathercocking will change as wind speed and boat speed changes.



Changes in trim change the ratio of aerodynamic to hydrodynamic forces, so trim will also alter weathercocking behavior.



My Guillemot is all but impossible to paddle off the wind with the bow empty if the wind is stronger than 10 knots or so. Two liters of water in the bow allows me to easily paddle off the wind.

what he said…
so the wind and waves were pretty fun in Ilwaco?



we had gusts to 45 knots on MON.



steve

Yes and No
Oh man, you ever been ‘locked in’? Almost stuck? On several occasions I’ve paddled downwind in a large bay that narrows to a creek. As you near the creek there’s a bridge. If you get your boat sideways to the wind and waves (looking back for your kayak buddies) where the bay gets narrow you can have a hell of a time turning either direction. The stronger the wind the more difficult to get ‘un-sideways’.



No, I never tried to trim the boat to affect weathercocking. (I mash my T165 pretty low in the water).

The boat did like beam wind
I noticed that, too. The boat liked to be sideways to the wind and waves.



Boat turned best with quarter sweeps. At the bow to point windward (pinning the bow) and at the stern to point leeward (pinning the stern.) Problem with rudder strokes is I wasn’t moving very fast most of the time, often just holding my position in the wind while we did rescues, or mussed around about what we wanted to do next.



Paul

whether and lee cocking

– Last Updated: Oct-04-07 1:23 PM EST –

I've been paddling a Tempest 170 RM for 4 years now and have had no trouble with weather cocking, no matter what the wind speed---when the wind increases to 20+ with waves 2-3+feet I do have trouble with leecocking when the boat is empty. I have learned how to correct this somewhat with ruddering bow strokes, duffek etc. When my boat is loaded with camping equipemnt I don't have the problem. The reason why the explorer owner puts the water in his bow hatch is to prevent lee cocking which is caused by the boat's bow being too light and not deep enough in the water, thus catching the wind and forcing the bow to leeward. This can actually pin a boat---the first time it happend to me was in 25--30 knot winds and 2-3'seas---I couldn't get my tempest to head up into the wind by a combination of forward sweeps on the downwind side and reverse sweeps on the upwind side. Later figured out that the reverse sweeps were slowing the boat down and forcing the bow slightly higher in the water, preventing it from turning into the wind---the ruddering bow stroke on the upwind side solves this problem, as does weight in the forward hatch. I didn't know that then however. My solution was to run abeam the wind until I was in the lee of a small island then I could turn upwind and get to my destination. and wouldn't you know it, 20 minutes later the wind died. The only problem I have with putting water in the forward hatch is that it tends to shift, making a roll difficult if not impossible. WHOOPS---SHOULD BE W-E-A-T-H-E-R----sorry my fingers move faster than my brain.

Yup, way fun!

– Last Updated: Oct-04-07 2:27 PM EST –

That was one of those next-level paddles for me.

Felt like the boat was a real plus. Can't complain at all about how it handles in waves and the higher winds.

Once the wind picked up and the waves steepened and lined up I was pretty much riding on one butt cheek (beam waves) for the rest of the crossing from the boat ramp to small sand island. Then on the return, an hour or so on the other butt cheek. Very cheeky. That's a neat feeling letting the waves pick you up and slide you, while staying on course.

It was a little disconcerting heading straight windward, cranking to make any progress at all. That taught me to really lock arms and use torso.

Ah, the drift downwind was so nice. Just extend the GP out to the side and relax. Ah, but that we were heading net down wind, not!

Yeah, you live in a wild area, Steve.

Paul

Related Question/Observation
Is it also true that whether a boat is a “low windage” boat or not has very little to do with whether or not it exhibits weather helm? For example both my AA and Greenland SOF weathercock a fair bit in some conditions, but both are overall a joy in the wind, especially higher winds, since they have low profiles and really do not get blown around at all. I hardly notice the wind in them when using a GP except for dealing with weathercocking at certain points to the wind. They never “pin”, never get shoved around, and remain easy to turn when the wind picks up. Maybe in my head since easy to think weather helm and being affected by wind should be directly related.

not sure
Ed I’m not sure about low profile boats being effected by wind re weather cocking, I am sure that high profile boats, like the Tempest 170 and possibly the explorer do get effected by the wind as far as lee cocking—but I’ve never had a problem with weather cocking with the tempest—if it starts to w/c usually is very easily corrected by a single rudding brace or forward sweep–in more extreme conditions the skeg is put down a little further than normal but have never had a real problem with it, unlike the lee cocking issue which as you know has caused me problems in the past.

More leg weight in the cockpit

– Last Updated: Oct-04-07 2:50 PM EST –

I suspect I have more leg weight more forward than most. The foot pegs set all the way out are still too close for me on most boats, including the Tempest. I removed the foot pegs and foamed the BH. That may be why I get weather helm in lower winds and neutral in higher.

I'm gonna weight the back compartment down in the future for the typical crossing in 10-15 knots.

Really great to compare notes with the rest of you.

Paul

Terminology

– Last Updated: Oct-04-07 2:58 PM EST –

I was wrongly using the term "weather helm" in the title to mean the general effect of wind on the boat. I looked it up afterward and realized weather helm is specifically the effect of wind to steer the boat to windward. Same meaning as weather cocking. I think the term "weather cocking" is just a bit slang, refering to the rooster weather vane which points into the wind.

Is there a general term for the effect of wind on the steering of a boat, without regard to whether it turns the boat to windward or leeward?

Paul

Weather helm… Lee Helm…
Sailing terms…



When the boat wants to head into the wind, you have to pull the tiller(helm) to the windy side of the boat or “helm to weather” to hold a course.



Opposite is “lee helm”, when you have to push the tiller to the lee side of the boat to hold course…



Basically weather cocking and weather helm would be the same tenancy for the boat to turn upwind. But not having a “helm” in a kayak it is generally referred to as weather cocking.



Just don’t say “sheet in” in a kayak.:slight_smile: