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How a yacht works: sailboat physics and design

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Re: How a yacht works: sailboat physics and design

#41
If you click 'Home' it is apparent this page is actually about radio-controlled racing yachts, which unlike the HN title explains the weird scope.

Vessel design goals not mentioned in other comments: cruising requires storage space, seaworthiness, living space, will generally prioritize stability/safety, may prioritize low draft for tropical anchorages, may prioritize single-handed sailing, etc. Autonomous vessels which may require visibility, minimum height, battery storage, stealth, etc. Multihull vessels are not discussed, even though they dominate in many categories because they are generally functionally superior in many regards (speed, comfort, safety, living/cargo space, low draft) but cost more to acquire/maintain. Once you study this stuff enough you realize there's a reason why ~nobody cruises on trimarans, people without extra money avoid catamarans, people with enough money prefer to cruise on catamarans, and large seagoing ferries, military and cargo vessels with speed as a design goal are also usually catamarans.

Fun fact: IIRC catamaran comes from kattumaram meaning "two stick tied together" in Tamil, the ancient Dravidian language of southern India. As such it is one of the few Tamil roots that entered international English vocabulary. South Indian seafaring empires once dominated sea trade as far east as Vietnam. Small multihull vessels are the hallmark of the Austronesian peoples, who are believed to have spread from Madagascar to Taiwan thence taken flight to populate the Pacific Ocean. Got breadfruit?

Re: How a yacht works: sailboat physics and design

#42

I've been super interested in sailing since moving to San Francisco and running around the marinas/Embarcadero. Did some digging and found a sailing school that I haven't asked about classes (yet) https://www.spinnaker-sailing.com There's even a school that offers boatbuilding lessons in Sausalito -- a bit too far/much of a time commitment for me! https://www.spauldingcenter.org/current-offerings

Cal Sailing Club is a great way to start. You'll learn more quickly on dinghies than keelboats and the skills will benefit your entire sailing career as you move on to bigger boats.

Also check out the Friday night races at Berkeley Yacht Club. Skippers always need crew so it's pretty easy to get a ride. Just hang out at the gate between 5 and 6pm with your gear and say hi!

https://www.berkeleyyc.org/racing

Re: How a yacht works: sailboat physics and design

#43
post #6

I've been getting into sailing, solely for the purpose of cruising and sailing for fun with no interest in racing. As I've started talking to sailors, I've realized that you need to gauge whether you're speaking with a racer or a cruiser. Racers will claim these are not mutually exclusive categories, because of course racers can also cruise. But racers who cruise will ultimately talk to you like racers. Racers are, a…

I've been seeing some modern junk rig refits on the great lakes the last few years, which really gives me hope about dedicated "get there when we get there" sailors. Those things are basically optimized for chilling the fuck out. Easy to sail (entire tacking maneuver is basically just throw the rudder over and duck), easy to reef, don't heel as hard, straightforward to mend the sail or running rigging on the fly.

Only downside is their close haul is like 12º off the wind vs a bermuda rig and no one knows how to make them. The east coast (esp chesapeake) has some traditional gaff rig setups that have similar tradeoffs, like catboats. I would love to see more small production boats target this end of the "speed/comfort/cost" triangle. Currently it's like if the only bicycles available were race-ready track bikes. But sailing is already a small niche and new boats even smaller I think.

Re: How a yacht works: sailboat physics and design

#44
post #2

This site is an absolute treasure trove of technical material on sail and hull design, with a focus on model yachts but most of the physics scales up. It covers aerofoil theory (momentum, circulation, lifting line), sail twist, downwash, planform effects, Reynolds number, hull resistance, appendage design, VMG, and more. Lots of spreadsheets and practical calculators too—bulb shape optimization, wetted surface area,…

Yeah, I miss the days when a higher proportion of this Internet was content like this.

I prefer these days, when the absolute amount of information like this is higher, even if there's also higher amounts of junk.

I can just not look at the junk today, compared to 25 years ago when the information I wanted only existed in a physical library in a different country.

Re: How a yacht works: sailboat physics and design

#46
I know nothing about sailing. I've been on a few sailboats. I love the idea of wind power - probably why I like flying remote control sailplanes.

I would love to volunteer on someone's race/sail boat to get some experience. I'm happy to take the ASA introductory course or ? course.

Any advice on how to move forward? I'm in the Seattle area.

Re: How a yacht works: sailboat physics and design

#47
post #46

I know nothing about sailing. I've been on a few sailboats. I love the idea of wind power - probably why I like flying remote control sailplanes. I would love to volunteer on someone's race/sail boat to get some experience. I'm happy to take the ASA introductory course or ? course. Any advice on how to move forward? I'm in the Seattle area.

I have just started sailing in the UK. I can't recommend it enough. It's great time away from the computer in nature but still doing really complex technical tasks. The best thing imho is to find and join a local club. There are many that aren't snooty (having Commodores etc) and it's pretty affordable. Members will always be looking for crew. I really wish I had done it sooner.

Re: How a yacht works: sailboat physics and design

#48
post #46

I know nothing about sailing. I've been on a few sailboats. I love the idea of wind power - probably why I like flying remote control sailplanes. I would love to volunteer on someone's race/sail boat to get some experience. I'm happy to take the ASA introductory course or ? course. Any advice on how to move forward? I'm in the Seattle area.

I have just started sailing in the UK. I can't recommend it enough. It's great time away from the computer in nature but still doing really complex technical tasks. The best thing imho is to find and join a local club. There are many that aren't snooty (having Commodores etc) and it's pretty affordable. Members will always be looking for crew. I really wish I had done it sooner.

I should say -- better in my experience to find a community run organisation run by its members than a commercial operation in my experience. A lot of clubs run on the enthusiasm of their members and this means lower prices and more opportunities to get involved

Re: How a yacht works: sailboat physics and design

#49
post #46

I know nothing about sailing. I've been on a few sailboats. I love the idea of wind power - probably why I like flying remote control sailplanes. I would love to volunteer on someone's race/sail boat to get some experience. I'm happy to take the ASA introductory course or ? course. Any advice on how to move forward? I'm in the Seattle area.

Join a club. There's also facebook groups looking for crews. But i guess if you don't have experience, you kind of have to provide an incentive like contributing higher towards the common costs.

Re: How a yacht works: sailboat physics and design

#50
post #25

On a related note, I would love to see an animated explanation for how sail ships worked. As a fan of Hornblower series,I suspect most of the relevant details went over my head because I didn't understand this.

Seems like a good contender for a https://ciechanow.ski/ interactive article.

That's exactly what I was wishing existed when I was looking at these walls of text. There's https://ciechanow.ski/naval-architecture/ which is interesting, but not quite the same
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