Login | Register

Post new topic Reply to topic  [ 70 posts ] 

Sat Apr 25, 2015 10:57 pm

Offline
Regular Contributor
Joined: Tue Feb 24, 2015 11:47 am
Posts: 159
Age: 70
Location: Fremont, Ca.

Getting back to the specifics of go faster boat design for low powered vessels which are required to ship considerable weight of stores, crew, and safety gear for a trip like this develops some interesting leads.
Basically, for much of the course we are boxed in by the lack of wind and the need for multiple crew to supply sustained propulsion.
Ok , so looks like windless planing or foiling might be off the table, when you are looking at a thousand pound laden weight and a continuous max power value of only a couple of hundred Watts available..
One of the big opportunities to excel at a meet like this is to keep the team going when there is no wind!
Looking at traditional load carrying rowing boats is helpful to a point..but where has there been more recent modern development of low powered heavily burdened craft? Particularly in the propeller driven realm?
I am thinking transoceanic bulk carriers. The designers of these impressive but occasionally also ultimately "small" vessels have money to spend on research because they need to have stable efficient platforms to stay profitable. These hulls are displacement all the way. What have they come up with lately?
Well, there might be some payoff here for us.
One thing that's been around since the 70's or so is that big counter-intuitive onion bulb forefoot, you know the below waterline teardrop entry? Never seen one on a small craft..maybe now's the time to give it a test..
Another big boat trick, off tugs this time, is the Kort nozzle, a circular foil surrounding the prop for greater thrust. Could this help a leg powered prop as well?
Naval architects and engineers are paid to put innovations in place because of bottom line dividends, they may have discovered some apps that we can adapt!



Top Top
  Profile Send private message WWWMSNM/WLM

Fri May 08, 2015 12:54 pm

Offline
Regular Contributor
Joined: Tue Feb 24, 2015 11:47 am
Posts: 159
Age: 70
Location: Fremont, Ca.

Of course this "perfect boat" concept is flexible, even arbitrary, depending on uses, waters, weather, economics, crew, and scores of other factors.
The R2AK narrows and expands considerations mightily, but it remains a vast field. You want to survive, you might want to win.
It would be nice to enjoy the entire process from first hearing about the race, to putting all the gear back in the shed.
What you end up with are some of the classic parameters of good boats in all seas, and seasons.

1. Strength. (Logic)
If she can take more than you can..that's a good start.
Bouncing more than once on a rock is helpful.
Hanging happily from her cleats says a lot.
Taking a knockdown or collision, with rig and hull
still servicable, that's a gold standard.

2. Design. (Aesthetics)
Seakindly? Comfortable? Dry? Pleasing to
Senses, Mind and body?
Shaped by the sea and wind, and the man-made power applied.?

3. Function. (Ethics)
Appropriate material, technology and economics to the task at
hand? Graceful multipurpose, or extreme single use?
Efficiency level?

4. Traditional, Innovative, or Hybrid. ( It's alive!)
That would be your call!



Top Top
  Profile Send private message WWWMSNM/WLM

Fri May 15, 2015 3:45 pm

Offline
Regular Contributor
Joined: Tue Feb 24, 2015 11:47 am
Posts: 159
Age: 70
Location: Fremont, Ca.

The Perfect Boat is not only heavily contextual to it's uses, waters,
costs, owners, and all the rest, this vessel is also heavily invested in the fashion of it's times.
Successful innovations are rewarded by extension, refinement, and elaboration, and are often taken to the limit and beyond, applied in randomly inappropriate ways and are prone to become fatal flaws in otherwise nearly "perfect boats". Competitions like the R2AK often become showcases for "the latest"
The work of the sea and human error enforce wonders of correction and the establishment of boundary controls.. But the results are not immediate..
Until workable limits get evolved, enriching the wisdom of maritime tradition, there is that curious headlong following of the style and technology. The trend and an approving clientel, and designer-builders anxious to satisfy the style demand, in large part drives the market.
Listen closely enough though, and you can sometimes hear whisperings around the docks....
......"The Emperor has no clothes..."



Top Top
  Profile Send private message WWWMSNM/WLM

Sun May 17, 2015 6:32 pm

Offline
New Contributor
Joined: Sat May 16, 2015 1:23 am
Posts: 17

I like the finish with the sweep boat option. So the 'perfect' boat for me would be one that does 25 miles a day, but capable of 75 miles a day once the sweep boat is in sight. :-)

With no engine, I would want something that sails well, but not necessarily fast, when there is wind. I would also want to be able to row or skull or paddle it, but only when necessary. I think I would be fun to embark with food for 30 days also. I presume you can make water along the way. Rules aren't all that clear, but I presume solar power and batteries are ok as long as you don't use it for an engine. What are the options these days for affordable desalination?

I think the perfect boat for me would be something 3 handed, so when I get out of hand I could be voted down. I have an Yngling, so I guess that would be the perfect boat for me. I just happen to be on the less than perfect coast, at least for this one. I haven't sailed our Yngling yet, but I am still deciding on options for getting back after dark with no wind. Thinking oars, or paddles. Not sure yet have to wait and see. This would be lots of fun in a Scamp.



Top Top
  Profile Send private message

Mon May 18, 2015 7:06 am

Offline
Regular Contributor
Joined: Fri Feb 01, 2013 1:35 pm
Posts: 41

We're finally on the water - Sealark, my new trimaran. Still finishing some things, and now have two weeks to get everything sorted out and get experience on her. I've posted a picture on http://www.scotdomergueblog.wordpress.com and will be making posts occasionally.



Top Top
  Profile Send private message

Tue May 19, 2015 9:44 am

Offline
Regular Contributor
Joined: Tue Feb 24, 2015 11:47 am
Posts: 159
Age: 70
Location: Fremont, Ca.

Scot!
Congratulations on the launch of S/V Sealark!
Doncha think, after all, the most perfect boats in the world are the ones we build ourselves, for ourselves?
That is an impressive piece of engineering and craftsmanship..
You learned a lot building it, and it will continue to instruct you in the ways of boats, wind, sea, and psychology!
An innovative, unique, and beautiful vessel.
May you serve each other well.



Top Top
  Profile Send private message WWWMSNM/WLM

Sat May 23, 2015 9:58 am

Offline
Regular Contributor
Joined: Fri Feb 01, 2013 1:35 pm
Posts: 41

Sealark had a structural failure yesterday. I think it will be easy enough to correct, perhaps losing the swing-in amas for rowing, but I won't do it before the race, so we are out. We plan to haul her home to Twisp tomorrow. We still hope to participate in the pre-race festivities in PT and see the fleet off (at 5am?!*#&?? - maybe).

I'm not sure what's next for me, nor whether it includes more work on Sealark. If anyone is interested I might consider selling her or parting her out - lots of valuable stuff: 22' custom carbon fiber mast, sails, solar power system for electronics, masthead tri/anchor light, etc.

Best wishes to all!
Scot



Top Top
  Profile Send private message

Sat May 23, 2015 11:01 am

Offline
Major Contributor
User avatar
Joined: Tue Oct 05, 2010 9:57 pm
Posts: 462
Location: Salish Sea

scotdomergue wrote:
Sealark had a structural failure yesterday.


Scot:

where/what was the failure? (just being curious).

_________________
--
:: Dave Scobie
:: Liveaboard on SV SWALLOW - https://sv-swallow.com
:: Owner of M17 #375 - SWEET PEA - https://m17-375.com



Top Top
  Profile Send private message WWW

Sat May 23, 2015 11:41 am

Offline
Regular Contributor
Joined: Fri Feb 01, 2013 1:35 pm
Posts: 41

We were sailing in a good breeze, thinking about putting in a reef. We came about to get some distance from shore before reefing and the starboard akas broke at the pivot bolts. I'd been concerned that was a weak point.

With ama attached only by tramp and lines, she went over - mast & sail in the water. We released sheets and I got around to stand on the daggerboard and pull on the tramp at the port ama, hauling her upright. We spent a half hour sorting things out and tying the starboard ama close along side the vaka before paddling & sailing (jib only, approaching 4 kt at times) the few miles back to Seafarer's Park in Anacortes.

Definitely good to do sea trials close to shore and help! Folks in a power boat immediately came out to offer assistance, though we were able to handle it without.



Top Top
  Profile Send private message

Sat May 23, 2015 6:04 pm

Offline
Recognized Old Salt
User avatar
Joined: Thu Oct 21, 2010 5:55 am
Posts: 640
Location: Port Ludlow, Washington

Scott -

What a bummer. So sorry to hear about that. A real heartbreak for you :(

_________________
Simeon
Voyaging with Noddy, #11



Top Top
  Profile Send private message
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 70 posts ] 

All times are UTC - 8 hours


Who is online

Users browsing this forum: No registered users and 5 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum


Search for:
Jump to: