Friday, May 28, 2010

Sailing On A Star

Moon Princess Kaguya from "The Tale of the Bamboo Cutter's Daughter"


A week ago Friday, JAXA* launched an H-IIA missile from Tanegashima Space Center. On board were four small earth orbit satellites built by Japanese universities as well as the main attraction - Akatsuki, a craft which will carry out an extensive study of the atmosphere of Venus. Also on board was Ikaros, a "space yacht" built by JAXA which is testing the use of the sunshine for propulsion.

Here's the launch and separation of Akatsuki from the launch vehicle (2 min 46 seconds)


The next clip runs about 12 minutes and details (with English subtitles) the Akatsuki spacecraft and mission. It's quite impressive and if all goes well, will provide a wealth of information about the climate of Venus, which in turn may help us to better understand our own planet.



As a sailor, I was curious about the Ikaros mission. Particularly, how one could use sunlight to "tack" "upwind" in space to a planet closer to the Sun. Essentially, the sail is set so that the spacecraft's orbital velocity around the sun is slowed by the sunshine (photons). In other words, the sail is used as a brake, like when backing the jib on Bluesette. As the orbital velocity drops, the craft's orbit gets smaller - closer and closer to Venus. I found a website at Cal Tech with an excellent explanation of this - Tacking Solar Sails .

The Ikaros space craft (Interplanetary Kite-craft Accelerated by Radiation Of the Sun) carries a sail that is just 0.0075mm thick wound around its core. Ikaros will spin at 20 rpm to unwind the sail using centrifugal force. When deployed, the square sail will measure 46 feet on a side. This clip is in Japanese, but you can get the (ahem) drift by watching the animation. There are thin film solar cells and dust counters attached to the sail. In addition to testing the sailing concept, the development of this craft and a much large one later on this decade, will lead to lower cost solar cells - an important element of Japan's efforts to reduce greenhouse gas emissions.



Fair winds Ikaros and Akatsuki.

Until next, sweet sailing.

*JAXA website is here: Japan Aerospace Exploration Agency

Saturday, May 15, 2010

Capsize Drill

Nice video from Swarkestone Sailing Club in England, showing how it's done.



And when things don't go so well...

This clip from Severn Sailing Club on the River Avon features a couple of instructors demonstrating capsize recovery. The boat starts to turn turtle and it looks to me that the mast gets stuck on the river bottom, they almost lose the rudder, and in the end break the dagger board! (This is why I have a masthead float.)



Be safe out there. Wear your PFD.

Until next, sweet sailing.

Wednesday, May 5, 2010

Blast Off - 2010


Bluesette on the way to the ramp with new sails and new mast head float.


Our first day of sailing for 2010 finally arrived on Monday, which happened to be Japan's Constitution Day holiday. Smack in the middle of a "Golden Week" of back to back holidays, we expected a crowd, but we were the only sailboat on the lake. Apparently, others had chosen Sunday.

The wind was much higher than forecast and more than we had hoped for on our first day back on the water. I'm still nursing a rotator cuff injury in my left shoulder, which can hurt like a son of a ..um... gun, so wasn't looking for a workout. The wind was up around 12 knots and gusty with frequent directional shifts thrown in for good measure. That kept us too busy for taking any pictures while sailing.

Still, it was a good day. After a long reach and some downwind time, we spent the next hour and a half beating our way back toward the yacht club. Splashing through chop kept us wet - well, K blocked most of it, so not so much got to me ;) which was good since except for my sailing boots, I was just wearing cotton.





Usually the wind at Hinuma is from the northeast - off the ocean, which makes for smoother flow over the lake and easier docking. But Monday the wind was from the south. It's always tricky (for me anyway) to dock when the wind is blowing from the south - offshore, straight down the dock - as it can shift at any time and ruin an approach requiring a trip to the opposite side of the dock. So, as K was wearing a wetsuit, rather than risk us being blown into the dock by the shifting winds, she hopped off the boat in 1 meter of water, walked us the last couple of meters in, and tied us up as I lowered the sails. Maybe not an elegant display of skill, but safe and effective. As my first flight instructor used to say, "any landing you can walk away from is a good one."

So how were the new sails? They worked well, I like the way they go up and down with much more ease and big windows are a nice feature. Whether they are any faster, I don't know - we were overpowered most of the time and just trying to keep the rail out of the water. I think on a more moderate day - say 5 to 9 knots - any difference in speed will be more evident.

As for the mast head floats, we didn't need them this trip. It does seem to me that not having the weight and drag of the Hobbie teardrop atop the mast is a better arrangement.


Three generations of the Hakuta family bring Bluesette out of the water


It was past two o'clock when left the yacht harbor, so we stopped at Mama's Kitchen for a late lunch. Luckily, they were open and after a salad and pasta (my pasta had a delicious tomato and crab sauce) Mama treated us to some banana cake. While we finishing that, her daughter was taking rolls out of the oven and gave us two of them to take home - K had cinnamon, and I had raisin. - yum. They spoil us.



Bluesette at Hinuma Yacht Harbor - Good sailing, food and friends.


Until next, sweet sailing.