Category Archives: Department of Public Works

Atanua Marina

Over the past two years, the Linden Department of Public Works has greatly expanded the opportunities for mainland sailors. In Sansara, they upgraded Sea of Fables with new racelines and content, and then added roughly three dozen new coastal waterway sims to provide Bay City with both North and South passages to sailing areas in East Sansara and Heterocera.

The efforts in Nautilus have been equally impressive, with the development of Dire Strait, a new passage to Corsica, and the addition of many coastal waterway sims at strategic points to make extensive cruising possible.

Leeward Cruise July 10 2012

Satori (aka the Southern Continent,  the Japanese Continent, or Mãebaleia) is now getting attention as well. Satori, like Gaeta (and I suppose like Australia too) has few inland waterways, and it’s coastal routes were cluttered with impassable builds. Well, that’s slowly changing as new water sims are added on both the East and West coasts.

 

Leeward Cruisers applauded this change and made several excursions to Satori in recent months. Well, on Tuesday July 9 LCC’s at it again with a cruise that will start from the Atanua Marina and end at DYC in Knaptrackicon.

Kudos go to Abnor Mole for his very nice Atanua Marina build that will be LCC’s Tuesday launch point. It’s located in the Northwest corner of the sim, and it’s horseshoe-shaped, with a large, protected dock area facing south.

The rez point is thoughtfully done as well. It encloses the entire marina area, but then extends a good distance south over open water. Even a large flotilla should find ample space to stage a start there.

One of the nicest things about the Atanua Marina is the long rez time; autoreturn is set for 30 minutes there, so there’s no need to rush if you need to make last-minute repairs to your boat before you get underway. 🙂

Come cruising with Leeward on Tuesday at 5:00pm SLT, and see if you agree Atanua’s a nice addition for sailors. If you like it, be sure to say thanks to Abnor Mole and Michael Linden next time you see them! 🙂

J-Class Numbers

J-Class numbers

Numerology

Since the J-Classic Regatta Series is warming up, I went hunting through old files and spreadsheets I have on  J-Class, trying to see if I had any performance data that I hadn’t gotten around to post yet.

multi trudeau

The image above is fairly old, but I think it’s still accurate. The chart that compares the performance of the J-Class without a spinnaker to the Trudeau Twenty, the Knockabout, and the Leetlecat. When wind= 5.0m/s, you can see the major difference between the boats occurs predominantly on upwind performance. Using just main and jib over 100° apparent, all four boats are pretty similar.

I also threw in the knockabout performance data with winged sails over 130° (shown in pink). Winging the sails enhances performance over 140 degrees in knockabout and T20. There is no performance boost in the J-Class, however. (C’mon… that’s why you have a spinnaker).

ez-hud-main-spin

 Here is another, fairly similar example of performance With different sails.
The blue line in the above chart shows the Speed Over Ground for the J-Class Using the EZ-HUD that comes with the boat. That’s a quick way to get the ‘manufacturer’s recommended’ sail settings. I then plotted the boat speed at different angles using  just the mainsail or just the spinnaker. Those results are shown in green and red above.
 The chart showsthat with 5.0 m/s wind, the spinnaker becomes effective with apprent wind angle >90°, and the spinnaker boost effect is rather substantial over a broad downwind range, falling off quickly over 170.

  polar-2

The image above is a polar plot showing similar data for the EZ-HUD, mainsail, and spinnaker. The shape of the spinnaker curve is a close match for the RL parachute.

11-and-5mps-plus-reefing

The next chart (shown above) shows a similar graph, but in this case 11.0 m/s  wind is compared with 5.0 m/s. With both wind speeds, there is a big jump in performance (i.e., boat speed) when the boat fall off to 40° apparent. 

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New Lines, No Rocks, Blake Bumps

Which object does not belong?

Which object does not belong?

Crows Nest Quiz

Remember those aptitude tests from grammar school? Look at the above picture of Crows Nest in the center of Blake Sea and decide which of the three objects does not belong.  If you answered Glorfindel Arrow, you lose 15 points and need to go back and study the thread on this topic at SlSailing.org.

On May 20, the  spectator’s platform is scheduled to move from Crows Nest to the southern end of Haggerty, facing north. That’s a much better location, and it will leave Fastnet Light as a solitary, majestic icon at the center of Blake Sea.

According to Admiral (ret.) MarkTwain White, the lighthouse will move slightly also, ending up “On the centerline (of Blake) between north and south and somewhat west of center.”

The Orange Race Buoy in Crows Nest, presently too close to the hazard of Fastnet’s rocky crag, will shift as well. It’s new location “Will make the orarge mark a great offset mark in connection to fastnet but not so close to the rocks…”

Danshire Plans New Line in Debelox

Thank you also to MarkTwain White for helping plan a new Linden race line for Danshire Yacht Club. We took a look at the options yesterday, and tentatively decided on Debelox, as shown below. The proposed line will be long for Big-Boat Races, and aligned for races with a default wind from the ESE. That should allow an ample pre-start mill area and long first leg options for races to Gaeta, or to the North or South Coasts of Corsica.

The planned line is still tentative, so please let me know if you have suggestions. We also don’t have a timetable for placement of the line, so please be patient. LL Department of Public Works is short-staffed and has many responsibilities. As soon as the new line goes in, however, Danshire will remove it’s current temporary line and fill in much of that space with expanded docks and club facilities for visiting sailors.
Proposed Debelox Raceline

Sorbet Rocky Road

Speaking of DYC, SL Sailing, and the Linden DPW, I’d like to give a big shout out to Michael Linden, who gave sailors a big assist yesterday by removing hazards on the SouthEastern coast of Gaeta.

Gaeta Grand Tour Course

Gaeta Grand Tour Course

In a sturdy boat with a quick breeze it’s actually possible to circumnavigate Gaeta in about an hour. The sailing is relatively low-lag with pretty stable sim crossings, possibly due to the reduced traffic and smaller number of builds on this island continent. That’s just a guess, I have no real numbers on it, but I am impressed that the sailing is about as good as it gets anywhere, at least for the moment.

Tig Spijkers has organized a number of Fleet races around Gaeta with strongly positive feedback, encouraging a lot of us to pull out our maps and start designing new courses that take advantage of Gaeta’s coastal waterways. Several days ago however our quiet regional promotion campaign to Sail Gaeta Now came to an abrupt halt, landing on the rocks both figuratively and literally.

Sorbet_003 copy

As shown in the image above, Sorbet sim lies on the southeast coast of Gaeta. The passage along the narrow outside channel was hazardous but interesting. It was full of massive, sculpted rocks that kept both skipper and crew awake. With skill and a little luck, however, most sailors were able to navigate the edge of Sorbet successfully even in large boats such as the VOJ or J-Class.

A few days ago however, the local sim owner made coastal adjustments that, when combined with the Linden rocks, inadvertently blocked the passage to most sailboats. Carmen Foden crashed trying to sail through and reported the problem;  I crashed in the same spot, and so did Chaos Mandelbrot and Tig Spijkers.  With that one change, suddenly Gaeta was no longer circumnavigable. As you can see from the above picture, there is a narrow canal, an inland waterway in the region, but it is far too narrow and shallow to support a keelboat.
sorbet

Tig contacted Michael Linden about the issue,  and I’m thrilled to say that he came up with a fix that rapidly reopened the coastal waters off Sorbet. The rocks are now gone, and he even placed two appropriately textured navigational markers (one is indicated  by the green arrow above). I thanked the owner of Sorbet for their support of sailing, and to make sure we were all good neighbors, I bought a lot of potted plants they had on sale there. If I give you a plant for Christmas, now you know why (grin).

But the real news is: Around Gaeta racing and cruising is now open again! Thank you Michael and DPW!!!

Blake Sea Shallows

Reseating the keel and replacing the bolts on a large racer/cruiser after you run aground can be a daunting task. If you’re ever in that situation, please get your doctor’s approval before you ask the yacht yard how much this is going to cost…  these days I think you could buy the entire city of Detroit for less.

I’m bringing you this public service advisory because the new Trudeau J-Class has an impressively deep keel that extends 4m below the water surface. It has a deeper draft than most other boats in the Trudeau fleet, but I don’t yet know how it stands up against other big boats like the VOJ or RJ-44.

I’m mentioning it here because there are several points in Blake Sea where the J-Class runs aground, and some of them are in strategic spots.

Atlantic Shallows_007

The water surface in Blake Sea (and most other water regions) is set to a vertical height of 20m. There are several offshore, underwater seabed mounds or ledges but rise to a height of 16-17m. Unless you’re careful and traveling familiar water, there’s a fair chance you’ll run into one of these shallow spots as you are cruising or racing. watching the depth gauge actually may not be much of a help, since a number of the underwater ridges come up fairly abruptly. You don’t get much time for evasive action, and it’s hard to know what direction to turn toward deeper water.

One place where this may present a serious problem is in Atlantic sim, near the blue-striped racing buoy. J-Class boats that mill north of the Atlantic start line or that participate in races that use the Atlantic buoy as a Mark  run a high risk of running aground. Races usually don’t anticipate that problem on a defined segment of the race course. As I’m writing this, Massy Johim just announced one-design J-Class races on the Atlantic line today; it will be interesting to see if this becomes an issue. In my own experience I have run ground and slid free, blaming it on lag or being ‘edited.’ My guess is that most of the time when sailors bang their keel on the bottom in open water they don’t realize what happened.

Blake seabed

Blake seabed

In the other cases, however I guess you could argue that shallow areas and an irregular sea floor are common problems in real life sailing, and so I shouldn’t be complaining about this. Well, actually I’m not complaining, I’m thinking about a fix to get around this issue. In real life I’d use a nautical chart that showed depths and gave a simple topographic map of the seafloor.  As far as I know, that kind of topographic map is not available for either mountainous regions or ocean depths in second life.

I’ve been talking to Tom247 Woodget, who’s actually interested in this kind of issue.  He thought a roaming bot that records location and depth might do the trick; the information could then be turned into a map.  However, I still wonder if there are easier ways to get this kind of information.

MarkTwain White visited the “Atlantic shoal” with me yesterday to see the problem, and suggested that any sailor who finds an unmarked shallow spot in offshore waters should drop him a notecard. He’ll collect them and take appropriate action.

In the meantime… if you see somebody walking across the ocean bottom of Blake, occasionally pausing to write down some numbers… its prolly me.

Passages

 ships-log-copy

Many strong and enduring relationships develop within Second Life that brighten our lives and teach us value and meaning. Inevitably however some of the individuals we love and admire here will pass away in real life, and their digital image will Suddenly disappear, leaving only an empty, inexplicable void behind.  

The sadness and pain we feel at the loss of a dear friend  may abate with time, but the core essence of  words, values and affection that we hold for them will not fade. It becomes part of who we are as individuals and it reaches out through our own thoughts and deeds to strengthen the common bond we share as a community.

linden-memorial-park009

linden-memorial-park013This simple truth is acknowledged each year in Second Life by a Day of Remembrance, when a series of events are held to record and celebrate the friends and loved ones that have given us so much, but are now gone.

This year the Linden Department of Public Works helped establish a more permanent, enduring monument to our SL friends and colleagues by erecting a twelve sim complex, the  Linden Memorial Park. The park opened to the public yesterday. The designers did a truly remarkable job. The park is notable for broad, open spaces of field and forest, with areas set aside for quiet reflection.

At the center of the memorial is a large pool fed by converging streams. A cascade of waterfalls rims the lake and give life to the stately calm of the Park.  A small island in the center  forms the stage for a Memorial Shrine that encloses a symbolic, enduring flame.

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