Wind instruments and expected Ericson upwind performance

[N.A.]

I'm almost at the end of a fairly massive amount of work necessitated by discoveries during an offshore shakedown last summer... thanks you for all who helped with the many questions that arose over the cpurse of all that!

Now, for the first time in years I have a working wind instrument (with the usual true apparent angles and speed), but I now also have a heading sensor. As a result, I am getting things like a "GWD" (Ground Wind Direction) and tacking angle, all next to my heading on the instrument display.

As a result, I have just discovered that my boat is incapable of going upwind
My heading angle to the true wind seems regularly to be greater than 90 degrees, 70 minimum. That's in 15-20kts TWS and boat speed of 6-7 kts, jib alone, 5' shoal keel, E34.

Furthermore, my angle to the wind (angle of attack? or is that just for the sails?) is typically > 45 degrees to the apparent wind, and... weirdly not the same on port and starboard tacks.

I'm sure all this has to do with my not having the (brand new) instruments set up right yet, and probably also my not fully understanding the different terms. But I had thought that good (race) boats could hold 30 deg to the apparent wind (heading; not including leeway etc for true COG). I'm nowhere near that, more like 45-60 deg at best. My jib is in good shape per the sailmaker, and was properly trimmed. Did not have main up, but with 90% jib was already at or slightly above designed-heel-angle. I don't think I was sailing badly (and I was definitely making way to windward).

A local boat (the Moore 24) is known for a slightly asymmetric hull leading to slightly differing behavior on different tacks, but I have never heard of that for Ericsons.

** What is normal for an Ericson (at least an E34-2) to be able to hold to the apparent wind?

** Is there any reason to expect this would differ on different tacks?

** is the a 180 deg to be accounted for in GWD (i.e., is wind from the North a GWD of 180 deg? That would still not make my numbers make sense, but would be good to know)

** Any other advice/suggestions for (Raymarine) wind/heading instrument set-up?

As always, any thoughts much appreciated.


PS: Probably related to all this is that the heading indicator is not yet calibrated. There is clearly deviation (heading-dependent, but never greater than 10 deg) between the Ritchie pulpit compass and the heading indicator... and between those and a handbearing compass. As a result I am not yet sure which of these is correct; need a smooth, current-free day to check against GPS. If the Ritchie is off, I'll be digging in the forums about how to adjust it to null-out deviation.

 

[Christian Williams]

For what it's worth, I've never had much luck with numbers on heading. And much of my upwind work is probably about 45 degrees off the wind.

There are so many factors. To check how close to the wind you can sail needs a steady breeze of 10-12 knots and a flatish sea, and careful sail set andheel angle, . And then to find the gravy spot between pinching and full. And then ask yourself whether although high, you might also be slow.

The only way to tell is racing, and even that's not always convincing. New sails matter. Helm skill matters. Heel matters.

Cruising boats are always a puzzle, and much of pointing is keeping up momentum, which relates often to helming waves. A dinghy such as a Laser, if you can find YouTube videos coaching how to sail them hard, reveals the athleticism required in throwing weight around, using waves, working the tiller and so on to achieve an average high pointing with full speed. There's a big-boat equivalent to all that, but it is dependent on experience and crew skill and equipment (A $20,000 mainsail).

Not much help, I know. I always felt, in racing days, that one tack allowed pointing higher. But verify? Tacking on headers in a shifting puffy wind just makes it all theoretical.

I rely on the masthead Windex on my E38. Oddly, when i am going fast to windward it has a very small angle indeed to the direction of travel. The Windex is almost pointing straight ahead. Which of course is a lie, but does allow me to keep proper course without the judgement of a compass.

Others will have different experience and perhaps a better answer to normal expectations.

 

[Dave G.]

IMHO...You need to use your main to point higher as it is the foil that controls actual hull direction the best. As in you can move the traveler upwind and push the boat higher, tighten the outhaul to change the foil , etc. How was your head sail trimmed ? Was it up against the spreaders ? Inside or outside track ? How big is the headsail ? In perfect conditions with near perfect trim you may get to 40-45 deg. TRUE wind. Apparent wind "happens" due to your boat speed through the water and the faster the boats goes the higher you will go into the the wind, apparent wind that is. If you were sailing upwind @6 kts and the true wind angle was say 50 degrees the apparent wind angle would be something in the neighborhood of 25-30 degrees, at 8 kts he apparent would be closer to 15-20 deg. Your windex on the mast always shows apparent wind angle when the boat is moving. True wind on your instruments is a calculation done by the instrument taking the apparent(windex) wind direction & STW to give you a true wind reading. When the boat is stationary like sitting at the dock both true and apparent are exactly the same. If you could slam on the brakes and come to a stop while sailing upwind they would also become exactly the same. There is a calibration menu on your instruments. You will have to find that mode. It will involve motoring in a large circle for 1-2 revolutions on a calm day . Make sure your rig is tuned as that will greatly influence upwind performance. If your wind angle varies greatly tack to tack you need to check the rig. Make sure the mast is centered and shrouds are tightened evenly. Of course every boat is a little different but not that much

 

[Out There]

I have always seen different achievable angle for different tacks but I have never had the data to know why. My best upwind angles have required pulling the main traveler up to about 66% windward with a cranked down sheet.

 

[southofvictor]

Hoist the main and see what difference it makes. I’ve messed around under jib only for fun and can’t point anywhere near as high without the main.
How’s your waterline trim? Our boat is a little heavy on the starboard side so we tend to point a little higher on starboard tack.

 

[frick]

On my 1971 E29, pointing high means proper trim on the jib. I would always have me Jib Sheeting way aft to flatten out the bottom of my 130 jenny. I would crank it in almost touching the spreader. Find the heal that is below backwinding, and provides the great speed. Make sure your boom is centered on adjust the downhaul for the proper twist at the top.

If you boat is faster on one tack than the other, you need to adjust your rigging. Mostly liking you mast head is not centered on the boat.

 

[N.A.]

Thanks folks; this is all very helpful.

@southofvictor : I'll check my waterline trim -- I had not thought of that, but both my (full) water tank and my (full) fuel tank are to port (moreso for the water, which is under the port settee; fuel is closer to centerline, but still over to port). Stove also to port... hmm; bunch of weight to port. Boat looks flat in the water, but the above suggests it probably isn't if I look harder.

I did (after my original post) put the main up, and... I could point higher! Well, actually, the wind was so high that I ended up pinching to keep the boat flat, which is to say (as Christian points out) that there are so many variables it is hard to get it right. [for the original post, headsail is a high-footed 90% and was sheeted up against the stays in ~ 12-18 kts wind depending on the moment. @frick Standing rigging was (literally) just replaced and should be reasonably in tune.]

I'll mess with it more. The new instruments make it feel (compared to my prior dearth) like an aircraft cockpit in terms of data, so I was trying to use it all. It's helpful to know from the pros (which several of you clearly are) that there is only so far one should push this. And I certainly do not sail at a level where it matters terribly; I can point as high as I can point, and the instrument reading will not affect that.

I'll try to check the calibrations -- I think they are not all computing using the same inputs (e.g. on further exploration, two different Raymarine displays report different apparent winds -- I can think of no reason for this other than that I have not set them all up properly. I'll look for the calibration menu @Dave G. describes -- with luck maybe I can do them all at once (multiple displays), though nothing ever seems to be so simple...

Probably the most important thing I've discovered in this (other than maybe the trim, to double-check with the rigger when he comes to adjust after it stretches in, and that 45 deg is probably about what I might expect) is that my compasses are not in agreement. That I definitely want to sort out, even if I rarely use them in this day of chartplotters.

Thanks again to all of you; this gives me plenty to look at. Very much appreciated.