What boatspeed should I expect, as a percentage of True wind?

[smj]

Originally Posted by GRIT

Going back to the Original topic:

I'll be arriving in Ft Lauderdale, from St Augustine, in 2 hours or so. I was just looking at the average speed, and thought I'd post it here. Going slower overnight, with 2 reefs in the main, and a reefed jib. A fairly relaxing trip overall.

Winds 20 with gusts to 30 yesterday, and now winds 15 with gusts to 20. 160 awa yesterday, 120 awa now.

I meant to get a photo at 24 hours, but this is pretty close.

Cheers.
Paul.

Just looking at this again and realized your actual speed through water must have been much higher as you must have been fighting a considerable current from the Gulf Stream for a good part of the trip?

[GRIT]

There were times when I had current in favour as well as against. Judging by the log, it pretty much evened out. It shows nearly identical distance through the water as distance over ground. I was generally within 3 miles of shore, and once south of Cape Canaveral, I favoured the shore a little more, sometimes coming within a mile of the beach.

It was quite bumpy for the first 100 miles, so I purposely kept the speeds lower for comfort. I had two reefs in the main and the jib was nearly useless, due to the angle of the wind. Overnight, it was quite gusty, so I kept the reefs in and eventually furled the jib completely, still making 7-8 knots. Shortly after sunup, the wind worked it's way a little closer to the beam, and dropped about 8 knots to the mid teens, and the seas lay down a bit. I took out one reef, and rolled out the Code Zero, to get the speed up.

A friend mentioned that I tend to travel when there's wind, which might make the boat look faster than in lighter winds.

Of course that's true, any boat can sail fast in heavy winds. I'm including a photo of the log for Nov 16, a trip from Winya Bay (Just north of Charleston SC) to St Augustine. Wind at 70-110 TWA, on average, and under 14 knots for the entire trip, except a strong gust about 50 miles into the trip, which hit 25 knots for 5 minutes. There was a northbound current of about a knot, for much of the trip, which slowed the progress "over ground" by 23 miles, as shown on the log.

Most of that trip was with the code zero up, and full mainsail.

Our last boat was a Corbin 39, which usually averaged about 100 miles a day. To say I'm chuffed at 200 miles per day, would be an understatement.

Cheers.
Paul.

[GRIT]

Originally Posted by fxykty

Still no upwind inside-the-shroud screecher for light wind upwind. With our 36sqm self tacker (plus 86sqm round top main) we are under powered under 9 knots TWS upwind. At best in flat water we can sail ~50% TWS but at closer angles 30-32* AWA due to the slower speeds for a reasonable but not exciting VMG.

I am still dreaming of a 70sqm screecher that will sheet to the aft corner of the cabin top for an effective angle of 6*. It only needs to go to 15 knots AWS so can be built fairly light. Unfortunately some structural upgrades take priority right now, but that sail and its sheeting position are next on the list.

All that said, due to our relatively new to us non-schedule cruising lifestyle we now wait if there’s not enough wind to sail well - fortunately on the mid Queensland coast that’s not too common. We do seem to be the one of the few boats willing to sail upwind though - we’re witnessing a lot of motoring or staying put during non-favourable wind directions.

Our gennaker (or code 0 I suppose it would be called now) does very well for AWAs 45-135* and even for wing and wing at 175* AWA. But except in really light wind (under 4 knots TWS, when we go slower) it’s hard to go upwind as the 90-100% TWS boat speed means our TWA is 75-80*.

I expect if we get the screecher then we’ll use the gennaker less and will want a large top down furling asymmetric for 80-170* AWA. We do have a symmetrical spinnaker that came with the boat but don’t use it much as it’s a bit more of a hassle to set up than the furling sail, but it does cover the 120-180* AWAs.

Now those are some good numbers! I don't know if we'll ever match them, but it's something to strive for.

We can only point to 60AWA with our code zero. It's nylon, and must be cut with a bit more belly than yours. I expect the screecher to be much better than our code zero, as it'll sheet to 7 degrees, but will be much smaller at around 55m2.

Cheers.
Paul.

[django37]

This is condomaram sailing, boatspeed is more than 50% of TWS to windward (mostly). OBS: TWS is measured in SI units (Airplane and boat speed may be measured in knots - other speeds in m/s) Current slightly against.

[GRIT]

Is that normal in the EU, for boats to use M/S rather than KN?

Those numbers look good, but I've seen so many people take pictures of their "best" numbers, which may have flashed up for a second or so, and say that this is what they're doing in real life. Any chance of you taking a one minute video, and posting that? I've asked Arsenpeluga to do the same, as his numbers are also very interesting, and he has a similar boat to yours, but he has so far declined to post a video.

The whole reason this thread was started, was because I couldn't find any real examples of how fast people sail in certain wind conditions, and at certain angles. It seems most people (I don't mean you) are deceptive about how fast they really sail, and it's promulgated the idea that all cats are fast, and can point nearly as well as a monohull.

I don't know if we're fast, but on a recent voyage around Cape Hatteras, we passed 14 catamarans (shown on AIS) in 200 miles, and 4 admitted they were motorsailing at the time. We didn't run the engine after leaving the anchorage, until 1 hour before dropping it again Cape Lookout. I therefore can assume we're probably faster than most of those cats (of course they weren't all trying for maximum speed). This makes me question any photos of instruments showing good/great speeds.

I started taking 1 minute videos of our boat's performance in certain wind conditions. I'm doing this for two reasons:

1. So more experienced cat sailors can comment on my speeds, and what they think I may be doing wrong (or right). Folks on this thread have commented on some of the videos, and helped me improve my sailing skills, which makes me happy to post videos like that.

2. To help folks who may be thinking of buying a catamaran, understand what realistic numbers might look like. Since so many people only show pictures, or don't show anything at all and simply state "we always make 200 miles a day" (which I read here on CF) I want to try to temper people's expectations, so they're not disappointed when they don't see those numbers themselves. (Like me!)

I've gotten quite a few e-mails and in person comments saying that our boat performs well, and better than the commentor's personal boat. Yet, when I read about catamaran performance, like yours and others, I often can't maintain the numbers they claim, and now I've started to wonder if they can themselves.

I can take a picture of some pretty awesome numbers, but they don't hold up for very long, which is why I take video. Even then, I don't take video of really poor numbers, so even those numbers aren't representative of "every day" numbers.

Please contribute a video of your cat's performance numbers, I'd really be interested to see it. Video of spray off the sterns, or bows, contributes nothing, please show the numbers for a full minute, and that'll really tell the tale. It would be nice if you describe what you've done to get those numbers. Lighten the boat, added sail area, special trimming tricks... to help us Newbies learn more about how to sail our cats "fast". PS; video with audio, as I do, just to show the engines aren't running.

Cheers.
Paul.

[django37]

Oh Grit, you dont have to believe me. I've owned a boat for 70 years now, have raced something like 2000 races, mostly in dinghies, the Lagoon is my 7th cruising cat, the last 6 years I've sailed her round the world. Of course she has some special larger sails than standard - condomarams are undercanvassed. But just forget, you have seen theese pictures ...