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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

#61

Post by CalChris »

WALoeIII wrote: post #4

Arvel Gentry must be mentioned, he transferred much of the aerodynamics research to sailing with an amazing series of magazine articles. He debunked a lot of faulty theories, like how the slot works, in a meticulous but approachable style. http://gentrysailing.com/magazines.html

Ugh. The slot theory lives on. The physics textbook still used at Berkeley, Giancoli, used the slot effect as an example despite … Gentry being a Berkeley grad. I sent a letter. I never got a response. However, the latest edition deleted the slot example and instead uses the Bernoulli principle yet stops short of Runge Kutta circulation.

Re: How a yacht works: sailboat physics and design

#62

Post by amelius »

reddit_clone wrote: post #3

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.

I'd love to have a simulator for a sailboat, preferably running in a browser.

Re: How a yacht works: sailboat physics and design

#63

Post by OldManAndTheCpp »

Zeetah wrote: 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 own (half of) a racing boat on the Great Lakes.

Buying a boat brings with it dreams of freedom, winning races, beautiful summer days.

The reality is that you need crew! Serious racers will refer to their boat as their “program”, and are always looking for careful, reliable crew.

I’d say look for a “learn to sail” program at whatever yacht club is nearest you, then see if they have a club racing scene. Most clubs have both.

Re: How a yacht works: sailboat physics and design

#64

Post by OldManAndTheCpp »

adriand wrote: post #57
efitz wrote: post #29

Earlier quoted context omitted.

Exactly right. I’ve known from when I started sailing 35 years ago that I was a racer. Sailboat racing is amazing; it’s this incredibly complex exercise involving physical boat handling skills, teamwork, leadership, communication (in a jargon that itself takes a year to internalize), as well as physics, geometry, meteorology, and minute observation of effects (that dark patch on the water or the flutter of a telltale…

That sounds like so much fun. How much of a demand does it place on you physically, ie how fit do you need to be to do it well?

Counterintuitively, the bigger the boat the less the fitness requirement.

Small boats (dinghies) require crew weight in certain places (“hiking” as far out to windward as possible) and have less mechanical advantage in the boat systems.

Larger boats, the forces scale out of the human range quickly and the crew relies on winches and pulleys to move the sails.

Re: How a yacht works: sailboat physics and design

#65

Post by OldManAndTheCpp »

lasermatts wrote: post #14

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

Other people have echoed the same advice, I’ll add to it.

Take enough of a learn to sail class that you understand the basic theory —- I took one at my local yacht club.

Then, find a racing fleet! Racing boats need crew weight to help the boat sail towards the wind (so you can be useful while you are still learning), and not all the jobs require as much sailing knowledge as others (my first job was to pull the free end of the line while someone was winching in the sail).

Skippers value consistency —- the boat can’t race without a crew, so literally just reliably showing up is a valuable thing.

Re: How a yacht works: sailboat physics and design

#66

Post by floren »

arnarbi wrote: post #16
lasermatts wrote: post #14

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

There are many sailing schools around SF, but one that stands out is https://www.cal-sailing.org/ - as it's by far the least expensive and low-commitment option to get on the water, and they have dinghies in which you'll learn very fast (but also get wet). Instructors are regular volunteer club members and mileage may vary, so make sure to go out with a few different ones. Another good way to get started is to find c…

I found CSC friendly but basically the boating equivalent of opening the encyclopedia at random and reading -- whichever instructor I ended up with would just decide what he wanted to teach/do that day, no structured curriculum. Presumably one could eventually learn enough to pass the test and be able to take dinghies out yourself, but I didn't have the patience--I bought my own and learned more in 30 minutes than I ever did at CSC

Re: How a yacht works: sailboat physics and design

#67

Post by cycomanic »

patagonia wrote: post #32
jp57 wrote: 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 learned to race first and am now learning to cruise. And I’m glad I learned in that order. Cruising has a very specific set of skills that you’ll never learn racing. That stuff will be obvious and if you want to cruise, you’ll learn those skills. But what is not obvious to cruisers is that racing teaches you how to handle your boat in many different and difficult conditions, with confidence. When you race you have…

Agreed. I used to race on a one design 34ft boats (steward 34s for the kiwis here). For the Thursday night rum racing they always casually divided up sailors amongst all the available boats and therefore the yacht squadron would refer people in town to them. So naturally we got a lot of cruisers on there around the world trips who wanted to try out racing. The most striking was the lack of urgency. Even though many were quite experienced sailors they were often worse than people who never sailed before. The newbies could be told to which as if your life depends on it and they would go full out, some of the cruisers not so much.

Re: How a yacht works: sailboat physics and design

#68

Post by Lefuz »

reddit_clone wrote: post #3

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.

There is a modern-ish simulator here: https://thapen.itch.io/painted-ocean

The tutorial level on how to get the ship pointed in the right direction and moving out of the harbour will give you the basics.

Re: How a yacht works: sailboat physics and design

#69

Post by lillecarl »

jp57 wrote: 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 was born into sailing though dad, and I know how he is about performance and ekking every little bit out of what he can (and can afford) (no huge stuff, 21ft). I mean I never let the sails go all out of trim, but I can appreciate putting it on good enough, setting the autopilot and just chill and listen to the sound of sailing, the sound of sailing in a mild summer day is peak life
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