Disclaimer: I still enjoyed the time spent on this, but....
I spent 2 hours talking with my highly inebriated and closest friend because she decided to spend Christmas with her family. Her shitty, shitty family who has always been some combination of neglectful and passive aggressive. She's also very sensitive and it still hurts her after all these years/decades that they treat her this way.
Celebrities could retire into obscurity, go away and be forgotten, nobody would bother them. But they want and NEED to be hounded, stalked, chased and be the center of attention.
I’m better at writing than talking because it takes me so long to think of so many words.
today I paused for 30 seconds trying to remember “second line of defense,”
and paused again for a really long time trying to remember what this thing is called I plug my phone into recharge when I’m traveling, oh yeah it’s called a “power bank.”
When I was younger and went out all night often me and my flatmates used to wake up and watch that until we felt better. Like 4 hours of it every saturday and sunday morning.
Please note that in aerodynamics, “lift” is any aerodynamic force that acts perpendicular to the relative wind on an object, so it’s lift whether it pushes a plane up, down, left, right, or pushes a sailing boat across the wind.
Also the keel of the boat that keeps it sailing in a straight line is technically providing lift in the water, although that “lift” is sideways. Also it isn’t aerodynamic lift, but hydrodynamic. The general field is called fluid dynamics, which covers both gasses and liquids.
You’ve got some good answers, but the problem with the air bouncing idea is that it ignores the air on top of the wing, or to the leeward side of the sail. The sail is pushed on by the windward air, and pulled on by the leeward air. (Edit: technically not pulled on, but you can model it that way if you take atmospheric pressure as 0 and anything lower than that as negative; it will give you correct results)
A better way to think about it is flow turning - as the wind moves past the sail, its flow is turned and the momentum change causes an equal and opposite change in momentum of the boat: www.grc.nasa.gov/www/k-12/…/right2.html
So ideally the leading edge of the sail should be parallel to the oncoming wind, and the trailing edge will be by definition parallel to the outgoing wind. The difference in velocity between these two winds multiplied by the mass of air passing over them over time will give you the force acting on the sail.
If the leading edge isn’t parallel, the air’s transition from free flow into contact with the sail will not be smooth, and will cause losses that reduce the efficiency of the sail.
In practice, the way to achieve this parallel flow is to let out the sail until you see “luffing”, which is just the leading edge flapping a bit in the wind. Then you tighten it until the luffing disappears, at which point the sail should be correctly trimmed. As you carry on you can occasionally repeat this process to check that you’ve still got the right angle, as minor shifts in wind or boat direction can change the ideal angle of attack.
This is also called “setting” the sail. So when a ship “sets sail” it’s referring to the fact a skipper would order the crew to “set sails”, which would start them moving. Now the term also means to commence a voyage.
In some bigger boats you have strings called “telltales” on the surface of the sail. If you see them flapping you know the air flow is turbulent, and you can trim the sail until the telltales on both sides of the sail are blown into a smooth line along the sail. If you tighten the sail too much, the leeward telltales will flap. If you let it out it too much, the windward telltales will flap.
A flat surface is much less efficient as it will cause a lot more turbulence on the leeward side. A lot of work has been done to make sails form the most efficient shape, and they are always deliberately curved. The shape will change depending on the tightness of the sheet (the rope that sets the sail) and on its manufacture, but ultimately your sail shape was basically set when it was made. Different sail shapes will be optimised for different types of tack and different tasks, but I don’t know enough about that to explain more. Mainly I know that spinnakers are made for running downwind and the other sails usually have to make do for the rest of the situations, but this article tells you a lot more: en.m.wikipedia.org/wiki/Sail_components
I only just found that article, so if it disagrees with anything I’ve said here I’d defer to it.
Very high performance sails and setups can do some cool things, like racing catamarans with their very sleek hulls and optimised sails allow you to sail in a close haul within 30-something degrees of the wind, whereas most normal sailboats can’t get much closer than 45 degrees.
Edit: This seems like a decent resource for first time sailors, and gives some more in depth explanation of how to set your sails correctly: www.cruisingworld.com/learn-to-sail-101/
This is also where I learned what telltales are called. I’ve never sailed bigger boats much tbh.
Okay, I think that’s most of what I can info-dump on the basis of your question. You landed on an intersection of two of my special interests lol :)
It’s completely my ignorance that i didn’t think of a sail as an aerofoil, in my lightbulb moment my brain thought, “fabric catch wind” in a very neanderthal voice.
I really appreciate everyone’s comments however i think with yours the nail is sufficiently hit on its head.
I haven’t done the full length of one but I’ve gone pretty far down one before
Basically you just need to figure out who owns the land and depending on that would depend on if you can legally or not
When I did it though I didn’t check first because I was basically banking on the fact it was near a national forest so if someone stopped me I’d claim (accurately) that I didn’t know it wasn’t a part of the national forest. Of course I’m not sure if it is a part of it or not, but if I did get stopped at least I’d know for sure. I didn’t get stopped but I did have a nice day out there.
Because it’s not needed outside the eastern US. The vast majority of land around me is public and anyone can go out. Right to roam would just give me the right to trample through someone’s property when there’s plenty of public land to go around it with, which is what right to roam usually entails anyways.
This is genuinely a states issue and not something federal.
Walking very close to someone’s home is also illegal with the right to roam. The right to roam just gives everyone the right to walk were they want except in someone’s garden. You can also camp anywhere (gardens excluded of course) for a day (or two can’t remember) without asking anyone for permission.
One kinda surprising thing is that everyone is allowed to enter fenced animal pastures, provided that they aren’t malicious and that they close the gate.
It’s an amazing right that should exist in the entire world.
You don’t seem to understand that my house, my town, and the majority of my state, are massive amounts of public forest. I have every right to wander and camp, as long as I’m not squatting (which is it’s own mess of an issue where what counts “permanently inhabiting” an area), anywhere in that public forest.
Why would my state govt have any reason to enshrine a right that would just make more people trespass because they don’t understand the law? Those that follow that law would then have nothing change.
This is why I say it’s a states’ issue. This won’t be the same across the entire US.
There are people who harvest wild food, yes. I think you need to understand that just our national forests are almost twice the size of the entirety of Sweden. Then there are state forests, national parks, and state parks. Texas alone is 50% larger than Sweden, and Alaska is 3x larger than Texas.
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