valis
Super Anarchist
I think you shouldn't extrapolate too much from her present heading. She's going to zig and zag as the wind changes, and I'm sure there will be many days where she sails at good speed directly towards her mark.
Jeanne Socrates - nonstop solo RTW 2018
- Thread starter Jud - s/v Sputnik
- Start date
ProaSailor
Super Anarchist
I perfectly understand being forced to tack but she seems to be favoring a dead-downwind style the last few days, which is slow in 10 knots of wind, with headings all over the place except towards the mark. I got very spoiled thirty years ago playing with Dick Newick's 50' trimaran Moxie - an entirely different animal - and it's difficult to adjust to the far slower performance expectations of Jeanne's monohull. It weighs twice as much and is substantially shorter LWL (32' vs. ~46'?) , though has surprisingly similar sail area. Ah, well... I'll try to shut up for a few days and just see what happens. Cheers.
SloopJonB
Super Anarchist
The bottom line here is - she knows what she's doing.
With her level of experience offshore I would be very hesitant to second guess her - on anything.
With her level of experience offshore I would be very hesitant to second guess her - on anything.
IStream
Super Anarchist
- 10,715
- 2,921
I agree, I'm just puzzled is all. I'm sure she's got her reasons and I'm sure they're good ones. Forgotten more than I'll ever know and all that...
When we did a simple transpacific, we ended up 300+ nautical miles NORTH of the rhumbline. And we didn't go far enough.
Rhumbline while shorter, was slower.
ProaSailor
Super Anarchist
blog: Day14 Tues-Wed 16-17th October 2018 Solar panels' power input doubled!
By Jeanne Socrates , on 17 October 2018 20:23
1600 PDT Wednesday - Position: 27.833,-125.775 - Speed: 3.9 knots - Heading: 187
Distance to 10N, 130W: ~1095 nm. at bearing 193. Thirty-nine degrees to starboard of rhumbline. Cosine(193 - 154) = 78% of boat speed toward The Horn, 22% toward her ITCZ target WP. (at heading 187... 84% toward The Horn)
242 nm. further to Horn Wp than rhumbline:
By Jeanne Socrates , on 17 October 2018 20:23
1600 PDT Wednesday - Position: 27.833,-125.775 - Speed: 3.9 knots - Heading: 187
Distance to 10N, 130W: ~1095 nm. at bearing 193. Thirty-nine degrees to starboard of rhumbline. Cosine(193 - 154) = 78% of boat speed toward The Horn, 22% toward her ITCZ target WP. (at heading 187... 84% toward The Horn)
242 nm. further to Horn Wp than rhumbline:
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SloopJonB
Super Anarchist
ProaSailor
Super Anarchist
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Jud - s/v Sputnik
Super Anarchist
- Thread starter
- #150
Webb Chiles’ approach is interesting. He waits for a good weather window to leave, leaves, has no wx info on board. Deals with what comes. No cosines required. It’s taken him very, very far indeed.
valis
Super Anarchist
I also wonder what has happened with her latest tracker positions, but based on the time difference and the lat/lon difference, she was averaging around 5.4 kts to the SSW. I think the indicated "-1.9 kt" speed and "-1 degree" are more bogus reports caused by some conflict between her tracker and her iridium blog updates.
As for her not sailing hot wind angles, remember that she likes to pole out her genoa, with the main out to the other side, which limits her downwind angles pretty severely. This configuration is wonderfully stable and forgiving (I use it a lot when not racing, and when the wind is strong enough to push me to the steep part of my hull-speed curve it's not a bad racing setup either.) Twin headsails are even better for deep downwind work, and much more stable than a spinnaker, but I don't know if she is rigged for this. She's not pushing for the best possible speed -- it's probably more of a "slow and steady, and don't break stuff" approach.
I also see from her recent blog entry that the earlier jog in her route was caused by getting spun and backed while she was sleeping. I think she has an "aux rudder" style of windvane, which is probably less able to steer her boat back on course than a Monitor-style servo pendulum. An off-course or wind-angle alarm might have been a good thing for her to have set up.
As for her not sailing hot wind angles, remember that she likes to pole out her genoa, with the main out to the other side, which limits her downwind angles pretty severely. This configuration is wonderfully stable and forgiving (I use it a lot when not racing, and when the wind is strong enough to push me to the steep part of my hull-speed curve it's not a bad racing setup either.) Twin headsails are even better for deep downwind work, and much more stable than a spinnaker, but I don't know if she is rigged for this. She's not pushing for the best possible speed -- it's probably more of a "slow and steady, and don't break stuff" approach.
I also see from her recent blog entry that the earlier jog in her route was caused by getting spun and backed while she was sleeping. I think she has an "aux rudder" style of windvane, which is probably less able to steer her boat back on course than a Monitor-style servo pendulum. An off-course or wind-angle alarm might have been a good thing for her to have set up.
oysterhead
Member
We have friends on a HR 39 that sailed from Ecuador (where we still are) to Easter Island over the last two weeks.
Easy sail, port tack the whole way in 8-15 knots. They are waiting for a window to depart for the southern Chilean
coast - and that is much more difficult this spring time of year - even from that far west. Nasty disturbances and
headwinds have been the norm for the past two months we have been watching.
She needs to be west and hope to get south of 40 deg S before getting nailed by something unpleasant.
Easy sail, port tack the whole way in 8-15 knots. They are waiting for a window to depart for the southern Chilean
coast - and that is much more difficult this spring time of year - even from that far west. Nasty disturbances and
headwinds have been the norm for the past two months we have been watching.
She needs to be west and hope to get south of 40 deg S before getting nailed by something unpleasant.
ProaSailor
Super Anarchist
That's ~2,174 nm. / 14 = 155 nm./day = 6.5 knot average, port tack the whole way, much of it a beam to broad reach. That's what I'm talking about !
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valis
Super Anarchist
Here's what I just posted on Jeanne's facebook page:
Jeanne continues to make good progress south. As she mentioned on her blog, she is no longer aiming to cross the ITCZ at 130W longitude, but instead is shooting for a crossing a little east of that, where the region is narrower. You can see the contrary winds she will be encountering south of the equator. This will be a challenge, but I suspect when she hits these (and if they don't shift by then), she will be sailing to the southwest for a while.
You can see some tropical storm and hurricane activity on the chart, but neither Hurricane Willa or TS Vicente will have much effect on Jeanne. Even the associated waves will have diminished to virtually nothing by the time they would be reaching her. There is a low-pressure system brewing (the yellow "X"), and NOAA gives it a 20% chance of developing into a larger system. Even this is probably too far away to affect Jeanne, but it will probably increase the amount of rain and thunderstorm activity as she passes through the ITCZ.
Jeanne was having some difficulty getting a usable image from the GOES weather satellites, which she planned on using to see the weather activity in the ITCZ. She and I traded some emails and we were able to figure out a way to get what she needs. These are fairly large image files, and would have been too big for practical download over ham radio or marine SSB radio email. Fortunately, she can also get email with her Iridium satphone (thanks to Global Marine Networks, good folks who I have used myself.)
valis
Super Anarchist
Speaking of GOES satellite images, has anyone recently downloaded these from saildocs.com? I tried, and got a horribly compressed image, with what looks like a halftone screen applied (this is a jpeg, but the original saildocs file was a .tif, 167 kBytes in size (I can't paste .tif's here):
There's a lot of obscured detail, and it seems to me that the compression could be better applied.
Here's a similar image off the NOAA server, only 81 kBytes:
View attachment evpn10 saildocs.tif
There's a lot of obscured detail, and it seems to me that the compression could be better applied.
Here's a similar image off the NOAA server, only 81 kBytes:
View attachment evpn10 saildocs.tif
valis
Super Anarchist
I also think this is probably wfax halftone screening. But compressing this screening (using either TIFF or JPEG) makes things worse, not better. I just got the latest image from saildocs and it's the same thing, so this wasn't a one-time issue.
NOAA has recently changed some of their sat image locations, so a lot of links are broken. Perhaps this is related?
valis
Super Anarchist
Here's an interesting chart I found on a U.S. Navy website: https://www.usno.navy.mil/NOOC/nmfc-ph/RSS/jtwc/pubref/References/GUIDE/chap2/ch2ap.htm
These are similar to pilot charts, but done in streamline fashion. For what it's worth, the chart was done in 1975. And obviously any particular day's wind may look quite different. Compare the above chart with today's conditions (below). Note the big low-pressure system due north of Hawaii, at 40 deg N. The wind there is rotating CCW, while the streamline chart shows a CW-rotation high pressure region. South of the equator it's a fair match -- for now.
These are similar to pilot charts, but done in streamline fashion. For what it's worth, the chart was done in 1975. And obviously any particular day's wind may look quite different. Compare the above chart with today's conditions (below). Note the big low-pressure system due north of Hawaii, at 40 deg N. The wind there is rotating CCW, while the streamline chart shows a CW-rotation high pressure region. South of the equator it's a fair match -- for now.
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ProaSailor
Super Anarchist
This image?Here's an interesting chart I found on a U.S. Navy website: https://www.usno.navy.mil/NOOC/nmfc-ph/RSS/jtwc/pubref/References/GUIDE/chap2/ch2ap.htm
These are similar to pilot charts, but done in streamline fashion. For what it's worth, the chart was done in 1975. And obviously any particular day's wind may look quite different.
P.S. I posted this because using Chrome browser, the image appears broken in @valis post. Not the case using MS 'Edge' browser... A certificate problem on the .mil web site.
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valis
Super Anarchist
Yes, that's the image. I'm using Chrome here and the image displays fine (all of them). Strange...