Chicken Rigs

So I had my ass handed to me yesterday in 17-20 knots (recorded, not guessed).

The wind wasn't the only contributing factor, I was being a scaredy cat with a lot of traffic around, but it made handling tricky, particularly at any hotted up angles and while trying to go slow (pre-start etc).

What are ppls opinions on chicken rigs? Usefulness, size, shape...

I've seen two recently, a purpose built full height one (higher aspect ratio) and an old KA with the bottom chopped off.

Good weekend

Just a quick on water update.

Had a good three races on the weekend. Jack, Markla and I were competing against a 16 foot skiff, a 29er and contender.

Markla and I are improving, Markla with his boatspeed and pointing (after some spreader changes) and my gybes are coming along nicely, about 50/50 foiling and half the rest with light touch-down before powering off again.

a special hello

a special hello to the two people this month who found the bloog (somehow?) by searching for Fonzie!

and before any of you eagle eyed people see me searching for it in the above image, it was just me seeing how far off the front page the bloog is. for those wondering i gave up at page 20.

resistance prediction, table of hydrostatics

resistance numbers and table of hydrostatics now available as part of the design package.

i don't really have much to say about them except they may be useful for anyone doing a VPP where the lowriding, or partially supported case is of interest.

SLINO Weight Estimate (with pie!)

here i am, friday night watching 7:30 queensland on ABC doing a weight estimate for a boat i have already built and weighed. 

well, its one of the remaining files i promised with the design package. and maybe i am feeling a bit compulsive. 

but it does show some interesting things. the centre of gravity is futher aft and lower than i would have expected as shown in the graphic below (note it excludes skipper weight)

the weight calcs result in the following numbers:
     hull, paint, gantry   = 11.87 kg
     wings (alloy), tramps  = 9.89 kg
     foils, tiller  = 8.50 kg
     rigging, standing, running, control, mast, sail   = 13.06kg

    Total = 43.33 kg
 
This distribution is illustrated below.

this is clearly 6 or so kg overweight. as I have noted previously, changing the wings to carbon would save around 3 kg. changing to dacron tramps (rather than trampoline material) would save some too. and I need to change to carbon spreaders. 

the remainder i think would need to come out of the hull. my construction method of laminating the seams of prefab panels results in a lot more bonding than a moulded boat (2kg i would estimate). 

how else to save weight? maybe less hull, particulary in the foredeck. or if you were confident in your boat handling maybe a lighter panel laminate, like nomex and prepreg. 

that rigging component is still a large piece of the pie. easy to see how a wing is viable from a weight point of view. 

updated design files

Some recent interest in the design has inspired me to complete the design package for the boat.

Lots of detail info here:

http://perverted-moth.blogspot.com/2010/11/slino-design-files.html

New drawings are:

SL2-E1-02__04A - Hull Construction Details
SL2-E2-01__02A -  Centreboard Construction Drawing
SL2-E3-01 Stem and Transom Lug Construction Details
SL2-E4-01 Wing Mounts Construction Details

SL2-F4-01A - Running Rigging Arrangement

SL2-G1-01A - Control System Arrangement
SL2-G1-02A - Control System Parts

I am hosting them on google docs. if anyone has trouble downloading them could you let me know and i will investigate different hosting arrangements.

The Truth is Not-there

Tonight's bloog is one from the vaults - my rather unpleasant, work necessitated Toastmasters experience. It is fair to say this speech went down better with the over 60s than the one on voluntary human extinction movement...

The Truth is Not-there

If the computer game THE SIMS 2 is anything to go by, getting abducted by aliens and bearing their children is as simple as buying the most expensive telescope and looking skyward.

While this isn’t going to harm your chances of getting abducted, there are a number of measures you can take to put your self in a more feasible position.

Today I will outline reliable means of being abducted by aliens.

Alien abductions are much more common than we think. Do you find yourself loosing time? Do you have missing memories. Do you find yourself in new locations with no memory of how you got there. Are you unexpectedly pregnant? If all of this sounds like last weekend. Then there is a strong possibility you were abducted by extra terrestrials. Does this happen every weekend? Multiple abductions are also common.

I understand those of you who want to have an alien experience face an uphill battle. The field appears rife with kooks and pseudoscientists desperate to discredit your chances. The prospect of medical testing or possibly becoming surrogate parents for alien-human hybrid super soldiers does not appeal to all. Most abductees describe the experience as terrifying or humiliating, but others describe them as transformative or even pleasant

Herein I shall outline reliable ways to get abducted. Then, how to determine the alien’s intentions and finally how to survive your encounter.

The methods to encourage abduction are simple, so lets start there

Be mentally prepared for alien abductions. If you come to terms with the possibility of abduction and prepare yourself physically and mentally, the aliens will look upon you more favorably. Find an inner mantra and mutter it constantly throughout the day. It is especially effective during the daytime in crowded public places where the aliens can sense the thoughts of those around you highlighting you as a perfect abduction candidate.

You can also hang around fellow abductees. Share their habits and interests. For some reason aliens like to take friends, family and associates of abductees. Then drive in your car along deserted roads in rural middle America during the early hours of the morning. When you see lights up ahead and your car radio goes crazy, then the car stops you know you’re getting close.

Make yourself an easy target for the aliens thru self medication of mind altering substances and alcohol. Intoxication will make you more likely to trip and fall and land in a UFO, amphetamines will sharpen your reactions and allow you to see or even catch a fast moving UFOs, and acid will elevate your awareness to tune your mind into the alien nexus and assist with tele-pathetic communication.

Of course your odds of abduction skyrocket, to excuse the pun, when you combine these chemicals in unfamiliar souroundings.

Once successfully abducted you should determine whether your alien means you harm

Can you establish the alien’s mood? If it is attempting to be friendly, chances are that the alien means no harm, but will probably probe you.

Notice how the alien is treating you. Trying to comfort is a much better sign than coming after you with a weapon, or the probe.

Look around you and see how the alien is treating the other abducted persons and animals. Are they harming them? Yeah, that also means your gonna get the probe

So How to survive your alien abduction?

I would suggest thinking pleasant thoughts about staying on planet earth. Aliens can read your thoughts and you don’t want him to misinterpret scenes of leaving earth or probes

If the aforementioned mind control fails, shout that you want to stay, in basic language repeated over and over. Even if their english is rusty the message should get thru eventually.

Reassure the alien that you mean no harm to him, remember that it has come from millions of miles away and is likely not to know what to make of you and your behavior either. Don’t brandish weapons at your first meeting if you can avoid it. It is hard to convince other humans that you mean no harm when you are brandishing your glock 9mm so it could be difficult to convince a completely different species that you come in peace and wish them to live long and prosper if you are armed.

Trust your instincts. If for some reason you feel uncomfortable around the alien see if you can gracefully get away from it. Try to convince it you need to check something out with your leader before attempting to represent the whole human race.

Should you failed non violent measures try fighting back. Even if the alien is stronger than you, as most of them are, putting yourself in their position who would take? Someone who just sits there and accepts they will get the probe, or someone who throws shoes and books at them.

Finally you can let them know that no-one has ever bothered to abduct you before, probably because you are too boring, or too normal. Most abductees are either an easy target, or crave repeated exposure to this marginalized lime light. So you can always try to convince the alien to seek out a more suitable candidate.   

That brings me to the end of today’s discourse. You have heard how mental conditioning, chemistry and the right positioning can enhance your chances of abduction. Next ways to tell if you will be probed, and finally, ways to ensure you get back home safely.

I would recommend that you don’t talk about your experiences. At best other people will think your crazy – at worst you will find yourself followed by black helicopters and men in black. Many people want to be abducted so you can see why the government is so keen to cover this up.

When I look around the audience I see some skeptics amongst you, but to you I ask this: can you give but a single piece of evidence to discredit the facts I have outlined today.

Look to the skys people because they are acoming. 

UFO? / Virtual Punter

n4rks sent this to try to prove to me he has a boat. and it flys. 

i think it is a rather sketchy photo, like those ones of nessie (teh monster, not teh wife), and ufos and stuff. therefore should be subject to doubt. i am even facing the otherway. and winning for that matter. well jack and steve are sort of in front but that's not the point. 

while not sailing nor working and bored i decided to try maknig a version of virtual spectator in rhino script to prove i can do anything in that program. i think it is the best and at 1k worth every penny. i am rather pleased with the results. rendering of the video needs some improvement but it has a lot of potential, and once i have 2D nailed 3D rendered graphics should be simple. background images were systematically raped from google maps at 5 different zoom levels to make up a matrix of around 20,000 tiles. but that is a different story. 

now i just need some decent GPS tracks. 

Hobart

I was in Hobart for a conference a few weeks ago and while sitting down for breakfast at 8am, noticed a lone rider carving up and down the Derwent.


Upon checking the BOM website the following was revealed...

17-31 knots in the hour or so on the water
11.3 deg lowest real temp
3.1 deg lowest apparent temp

Very keen...

housekeeping

a couple of pictures i have been sitting on from the worlds, first courtesy of Thierry and the second from Ben Rankine.

UPDATE: 

Karl, 

I purchased a 2 piece mail foil off a friend at the worlds and spent most evenings adapting it to suit the boat. Only got it ready for the final day of racing. On the way to the start line, after 20 seconds of foiling it failed thru the socket, pushrod tearing open the TE of the vertical. 

Once the lifter had departed, the rapid descent must have overloaded the bottom leg of the gantry, it bucking under compression. I have a Dave Lister style articulating gantry which saved the rest of the gantry, but it rotated up and snapped the tiller off on the hull. 

I was able to recover the lifter vertical, gantry and rudder were still attached, but the tiller/worm drive/extension goned. 

Windward Heel

Could've sworn I posted this ages ago.

I was wondering why 15 degrees seemed to be about the right windward heel for best performance upwind. Also wondered how much lift was actually required by the foil at such a heel angle and the transverse force balance of a moth at such a heel angle. Was fairly convinced this was all related so I developed a spreadsheet to find the heel angle that balances the vertical and transverse forces determined from the righting moments.



If anyone wants a copy to play with, let me know and I'll email it to you.

China and New Boat

Quick update, Markla is in China and I've finally bought a boat. All going to plan will pick it up Friday morning.

Clarke and Dawe

something to correct for narkla's recent left leaning posts...

[Scene: A car yard. BRYAN is perusing the stock. He is approached by JOHN]

John: Morning! Looking for a new car?

Bryan: Nope. New Prime Minister, actually.

John: You’re the third one this morning. Anything in mind?

Bryan: You know....... nothing fancy, reliable, economical family model. Something to get the country from A to B.

John: You mean like a Howard?

Bryan: Yeah....a little Johnny. Nothing flash, does the job. Low maintenance, economical, sensible. Runs for years, no troubles.

John: So.... you used to have one?

Bryan: Yeah. About 10 years. Great little model – don’t know why I got rid of him -- biggest mistake I’ve ever made…

John: What happened?

Bryan: Traded him in for a Kevin 07.

John: Big mistake…

Bryan: Lot of people bought it. Good political mileage.

John: How was the Kevin 07?

Bryan: Came with a $900 factory rebate – that was good.

John: Anything else?

Bryan: Not much. Sounded nice but nothing under the bonnet. It was a lemon.

John: Didn’t stick around for long did it?

Bryan: Nah – had a factory recall. Shipped overseas and was never seen again.

John: What was the problem?

Bryan: Lots. But the final straw was the navigation system. Plug it in and it automatically loses its own way.

John: Whatcha got now?

Bryan: It’s a Gillard-Brown.

John: The hybrid?

Bryan: Yeah. The Eco-drive system – not a good idea. An engine that can’t deliver hooked up to a transmission stuck in permanent reverse…

John: Green paintwork with a red interior. And steering that always lurches to the left for no apparent reason – that’s the one?

Bryan: The Fustercluck model.

John: The only one they made, Bryan. Not the vehicle of choice for the road to recovery – but did they finish up fixing the navigation system?

Bryan: Made it worse. Turn it on and it does a press release, heads off in all directions and goes nowhere.

John: So that’s why you’re here?

Bryan: That’s right. I’m stuck with a government that's wasteful, expensive, ineffective and past its use by date. I don’t suppose you’ve heard of the “Cash for Clunkers” scheme?

John: Join the queue brother.

will get back into moths soon, just waiting for it to warm up. 

and finish getting married.

and finish cresta #1.

Good photo of Mark from Worlds

W00t cadel

I'm off on a ride to celebrate

Course and Wind Plots

A couple of plots showing the Speed, Apparent and True Wind Vectors from the ride around the park. Unfortunately the Kestrel turned off after 15 mins, which was only about 5 mins after the GPS started tracking. But the concept looks to work. Now to fine tune the weather vane for the Kestrel, it had a tendency to go berserk in the higher winds, but otherwise working alright.

Speed (no colour gradient)


Apparent Wind

True Wind

All Vectors (culled the data for clarity)

All Vectors (a lot of data to sift through)

Foredeck

Just mucking around with some concept designs...





More of the hull, deck and wings to come. Not happy with them as a whole yet.

New Toy

So I've been thinking for awhile that GPS data on its own isn't enough really. How do you know what the wind is doing? Sure you might be going faster, but there may be a few more knots of breeze, you may be cracked off a bit...sooo many variables exist. Putting a big boat data system on a dinghy is not feasible.

On the drawing board has been an affordable wind guage/anemometer that can be mounted on a dinghy. There's been many sketches, but most have a fatal flaw. Electronics are getting more accessible and feature rich, just look at the smartphones, why not implement something for dinghy sailing. Then this came along...

http://www.nkhome.com/kestrel/kestrel-4500/

This piece of kit is allowing me to test some ideas to see if some sort of wind recording device is feasible/affordable for dinghy sailors. It might be that just a windvane mount for it is necessary as opposed to a dedicated electronic device. There are a lot of options from a fully featured miniature computer system to a bare bones data logger. I see no reason a small smartphone can't be setup in a waterproof box to record and possibly output to a display the real-time performance data of a sailing dinghy.

I mounted it on a weather vane on the bike and rode around the local criterium circuit on a windy day to get some data. Playing with it now and will post on the results once I have them sorted.

Excuse the short, rambling post, I'm sick.

New New Thing

My new new thing has arrived. It is sailing related, it is not a boat (although I'm looking at a few of those too). Once I've played with it a bit I will show you...

Second hand market

So I've been putting this off for awhile because I'm not really sure what to say. So what better way to say nothing than write a rambling blog post on a dull Wednesday night.

Having been in the market for a second hand boat for over a year now, the current market frustrates me. There seem to be plenty of boats on the worldwide market, but I can't justify paying anywhere near the asking prices. A number of boats have come round and round with very slight price drops every couple of months. One of my friends boats included, a good quality prowler zero. (Sorry Al, any publicity is good publicity right? :)

It is an interesting marketplace. Secondhand boats don't seem to be selling as fast as would be expected for such a "popular"/"high profile" class. Owners also seem to be willing to hold onto boats for as long as required to get a good price.

Clearly some secondhand boats are selling, we met some at the worlds, but it doesn't appear to be many compared with how many are still for sale doing the round'n'round.

Price doesn't seem to be a contributing factor with plenty of new mach2's selling.

Maybe I'm ranting a bit here because of my desire to be on the water instead of blogging. Sure I can afford these boats, hell even a mach2 if i want to demolish my savings, but there would be little point spending twice as much to have the same amount of fun.

For now I guess I'll keep stealing Markla's boat (once it is back in working order). It was behaving quite well during the short session I had with it at the worlds. It probably won't get as much attention two weeks from now anyway.

In other news, Markla has plenty of video from a session at Southport a few weeks ago (Post it Markla!). Markla also has to fit a near new ONE PIECE fastacraft foil to his boat. Long story short, he bought a near new two piece fastacraft at the worlds, we fitted it in one day, moments into its first airborne run it disintegrated at the joint ripping the pushrod out the back of the strut, plus plenty of other damage to the main foil, subsequent crash destroyed the gantry and broke the tiller, tiller (and the raking mechanism) were lost overboard, Mark was very upset. Word is that John Ilett was very good about it later and swapped broken main foil for near new one piece of his own after the regatta.

Twatter - marklamarkla

marklamarkla for twitter updates