Monthly Archives: September 2009

Blue Mars Open Beta

blue mars
Blue Mars is a new, three-dimensional online world with an ambitious agenda to build a diverse, global community.
The developers tout Blue Mars as a ‘next generation’ 3-D environment, one supposedly unfettered by the legacy limitations of earlier efforts… (presumably meaning Second Life). I’m writing about Blue Mars today because they recently went to “Open Beta,” so you may want to go take a look.
Here’s one of the promo videos:
Vodpod videos no longer available.
The sign-up is free, but (cough) the installation package is over 1 GB.  I also had to wait several days before my “application” was approved, and  it was  more than a little irritating  jumping through all the hoops to set up  my beta account.
Having said that, I admit it:  Blue Mars graphics are very pretty… and actually it was easier and quicker getting approved at Blue Mars than it is to  On the other hand, I guess, once you are “in” to Blue Mars, it’s pretty obvious this is still an early beta; the  resources and user development tools are largely nonexistent at the moment!

But if you sign up, you’ll find out that Mars DOES indeed have water!
Here is a screenshot from one of the (very few) regions currently open:

water on mars

I’ve only spent a few hours on Mars today, mostly getting my bearings and looking around. It certainly looks as though there’s a potential to develop a multifaceted sailing community there. It doesn’t look like it’s presently on their agenda, however. If sailing develops there, it’s going to take a rich, cooperative interaction between Blue Mars and the large group of fantastic, creative developers and single users from the sailing community.

2009 J-Classic: ROUND TWO

J-Classic Round two 800

Sheets to the Wind

sheets to the wind

by Ed Kegel and Moontears Vought

Greetings all! I’m fresh from Blake Sea, sunburned, wind burned, fed up with crashes (stopped counting after the first dozen) and worn out, but satisfied. I now understand her. No, not my girl friend, my J-Class.  Having just completed something I’ve wanted to do from the day I got her………. Sea Trials. And if you think this is a long note, well… it was a long day!

Sugar Reef

Sugar Reef

Have you ever wondered how she behaves under different sheet conditions? How close do I need to trim, for best performance? To reef or not reef, that is the question. And does she take after her distant cousin the Tako in regards to the Spinnaker angles, or does she have her own special needs? Just like a woman, she is complex, finicky at times, can be a real bitch,  but in the end – A JOY TO RIDE.

Many thanks to Moontears Vought, who helped me with this endeaver both with sailing back and forth on the Blake Sea add nauseum, and for being a great sounding board. Her thoughts are always sound and worth investigating. I would also like to thank the numerous other people who’s articles contributed to my understand of sailing in SL. Last but not least thank you Jane Fossett and JoyofRLC Acker, for helping to spread the wealth of information available in various forums and sources about this boat and sailing in general in SL.

OK, enough accolades; lets get to the results. I don’t purport to be a nautical expert, nor a marine engineer. But I do know how to conduct an experiment, limit changes to one variable as much as possible here in SL, and read the data. The conclusions I draw, while they may be up for debate by some, like the physicians debated a person’s illness in Moliere’s time. I am satisfied from the emperical, experimental evidence that I am on sound ground with my  conclusions and will sail her based on that understanding.

1. Moon and I wanted to find out if under a steady wind the boat exhibited any “sweet spots” or preferences in sail angles using the Jib and main sheets.

Venue was the open expanse of Blake Sea. Setting up our own wind at 12m/sec with no variations in speed or angle, we began trying various sail trims. To start we left the main in “Reef 0” condition. Moon was skippering, and I was aboard on the hatchway, centered and did not correct for heel. We took readings of AWA, sheet angles, and boat speed from the INFO HUD. Boat helm was adjusted via the left/right keyboard arrow keys, and sheet trim was made via chat commands imbedded in gestures linked to F-Keys.

A. The Jib and main sheets appear to like the same angle setting at least as far as the sea conditons allowed us to tell. Any mismatch beyond a degree cause a fall off in speed at all angles of wind, sail, and speed we tried.

B. For best speed at whatever heading, the boat wants constant correction of both helm and sail angle. Even with steady wind, to squeeze the last tenths of speed out of her you need to be sailing her every second. And given the variability of race winds, changing direction slightly all the time, its essential to keep adjusting the helm and trimming sails in and out by a degree or two. The AWA is constantly changing.

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J-Class Numbers

J-Class numbers


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).


 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.


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.


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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Getting over it

A Good Start copy
The 2009 J-Classic Regatta Series got off to a wonderful start this past weekend, with a truly fantastic series of first round races.
Since the teams include a number of crewmembers who are racing for the first time, and since we have eight more events  to go in the regatta series, I thought it might be  a good idea to spend a few minutes talking about basic race topics that will probably come up in the rounds ahead. The J-Classic fleet is full of wonderful, racing-savvy sailors who already know most of what I’m going to say better than I do… so I’d ask them to please feel free to post their comments, fill in what I forgot, and add their ideas and opinions on these and any other topics.
I wanted to begin by talking about about Race Starts.  In real life as well as in SL, getting a good start is often critical to a winning  a race.  The first boat that crosses the line on their intended course without fouling gains as a huge advantage, with open water and clean air.  Since there are no other boats around to cramp their style, the first boat over the line can set its own course and run the race just as the crew practiced it. The lead boat is the ‘alpha dog’ at the head of the pack, and its a huge advantage.
So? How do you get a good start? Here’s one simple strategy from Real Life.
“If you win the start, you can win the race.”
When the countdown starts, all boats raise sail and begin to jockey for position and build up momentum.
The prestart is easily the most crowded part of a race, and the Right-Of-Way Rules become critically important.
They often determine who captures the lead.
Rule 10 is:
10. Starboard Rights: Starboard boats have Right-Of-Way over Port Tack Boats
Under Rule 10 most skippers choose to start a race by crossing the line on a Starboard tack, since any boat on Port will need to give way.

The image below from this morning demonstrates this well; the entire Waypont fleet crossed the line on a similar starboard course.

Waypoint starts starboard
But if everyone is on a Starboard tack, you need another trick up your sleeve to get a startline advantage.  Most sailors go with Rule 11:
11. Leeward Rights: Leeward boats have Right-of-Way over Windward Boats
All the crews are vying to cross the line at the same moment, when the countdown hits zero
If you are the leeward boat during that countdown, all the others need to get out of your way. You not only get red carpet treatment; everyone else loses momentum trying to avoid you. It’s even better when you have several boats parallel and overlapped about to cross the line. If you’re the leeward boat, all you need to do is yell “LEEWARD!!!”  or “UP UP UP.” That forces the boat  adjacent to you  to turn into the wind, and often causes a domino effect. All the other boats upwind of them suddenly are forced to turn as well, while you stay on course and wave “bye.”
So: The strategy you want is one that puts you on a starboard tack and  positions you as the leeward boat as you hit the raceline a moment after it turns green.
There are two more nuances…
Most race lines are perpendicular to the wind, so it may not seem to make much difference which point of the line you cross. Well, take a look at Waypoint above… and pictures of any other expert race fleet. They are all starting from the end of the line at the windward buoy. That position gives them the longest  first tack moving toward the windward mark. They all know the boat that makes the fewest tacks while maintaining momentum often leads at the Finish. Those gybes along the way aren’t free; you pay for them in time and momentum. 
There is another thing about that windward raceline buoy, however.
 Take a look at the two pictures below from NYC Sunday Big-Boats a few days ago.  LDeWell Hawker was steaming in on a Starboard tack, aiming to slice the line at 00:00 sec on the far windward edge near the green buoy.  Gemma Vuckovic was also ready, though… a few moments before the top picture, she suddenlycame about, expertly falling into a parallel and overlapped position, just leeward and a fraction of a second ahead of Hawk. The lower image below shows them crossing together, close enough to whisper sailing complements to each other.
If this race were “serious,” however, Hawk knows that Gemma might not be quite so polite! As I mentioned above, the leeward boat has ROW. Gemma could call “UP UP UP”  and force Hawk to turn windward.  Doing so would most probably slam him into that innocent little green buoy at the line’s end.
Hawk’s a pretty great sailor, and he sees this strategy too; Gemma made her point that night. Enough said!
Gemma and Hawk off to a good start.

Gemma and Hawk off to a good start.NYC Big-Boat Race AUG 30

(Note: the start buoys are not considered obstructions or race marks under the Rules. You can’t ask for “Room!” under Rule 19, and sorry… Rule 18 doesn’t apply either. So if Gemma pushes you into a racline buoy next week, dont complain (grin) — it’s your own fault!) 
OK– A good, standard start then means: You do a Starboard tack, nose into the far Lee position, and point your bow at the Windward end of the line…
But just one more thing: After the Start, use your advantage to move into the Windward slot with respect to the rest of the fleet.You needed Leeward rights to control your start position while milling with the fleet in the countdown. Once you cross the line, however, your priorities change a bit; it’s Showtime.  Now you need to stay Windward of the fleet. In that location you can shadow any pretentious competition that tries to creep up on you, and you can defend your lead. After all, on an upwind beat, the windward boat can always speed up by falling slightly off the wind. The attacking leeward boat isnt so lucky; it needs to point higher to pass and it will lose momentum in that process. Even worse, the leeward passing boat has to get by the lead boat’s shadow. It’s not a easy task (grin).
Some of you may wonder if skippers actually use these tactics effectively in SL…
Grin. Maybe not as often as they should! But in the 2007 Tako Cup semifinals and finals, a number of excellent real life and SL skippers paired off, and used the Start Rules to great effect. They were so good and so relentless dueling for leeward advantage that a set of optional pre-start rules were introduced into the competition to make prestarts fair. The Rule changes were exactlywhat happens in real life as well to deal with this situation and it was pretty humorous … and quite amazing… to see it happen in SL. 
I know most sailors in SL and RL are pretty familiar with the strategy I discussed above. I also know it doesn’t apply in all cases, and a skipper being inventive and adaptive, using unconventional strategies in new situations is often important too. 
However, as in chess, choosing  an unconventional opening move can often prove pretty risky…
 On Monday Aug 31, for example, we did a practice run on the Round Two — Fruit Islands Racecourse. A gaggle of great skippers showed up to limber their muscles and stretch their wings across the course as part of their J-Classic practice. If anyone was contemplating some unusual tactics or was interested in testing a novel start, the Monday race was a good place to try it.
As you can see in the figure below, Oh boy did they try it. Despite a crowded pack of very smart, experienced skippers that would likely reach the start line at the same time together, separated by mere inches …
Two boats in the fleet attempted Port starts
Fruit Islands Big-Boat Race AUG 31

Fruit Islands Big-Boat Race AUG 31

As you can see in the second image, The Port start boats came within angstroms of  colliding with a wall of spar-and-canvas from the Starboard ROW boats.
Several of us gasped in horror and apprehension.
Of course, however, the fleet  are all pretty wonderful; they have considerable adaptive resources and were able to steer away, side-stepping catastrophe. Once the collisions were avoided, everyone had a good laugh over the audacity of the Ports starts, and the fleet barely missed a beat while turning away to  confront the real challenge: the J-Classic Fruit Islands course! 
It was pretty funny to watch it on Monday play out… but let me tell you, I’m bring ear plugs for Saturday. A Port start like that on Staturday’s Round 2 race will evoke a chorus of protests that could cause inner ear damage!