1

Flat Earth Theory / Re: Around-the-World Sailing Races?

« on: May 24, 2020, 03:59:22 AM »

I forgot about an interesting “around-the-world” sailing race that’s been ongoing since 1989 occurring roughly every four years.  It’s a grueling single-handed non-stop race from a port in France (a French sailor is the founder of this race) called the Vendée Globe.  They sail south to the Cape of Good Hope (southern tip of Africa), continue south to sail clockwise around Antarctica, then return to France, again non-stop, no outside assistance allowed.  Typically takes about 9 months.  There have been many boats from all different countries that have participated. 

One of the major strategic decisions the skippers have to make is that if they sail closer to Antarctica this distance they have to travel is less since they’re basically circling Antarctica, so that saves time, but then the odds of running into ice is higher.  And these guys have to sleep sometime.  Given the speeds these pedigreed racing sailboats can travel now if they slam into a big enough chunk of ice - their boat is destroyed and they’re dead.  They are not permitted any outside input like from meteorologists and satellite photos.  It’s entirely up to each skipper.  The typical sea conditions are 20-30 foot waves and winds in the 40-50 knot range.  An amazing feat of endurance.

But how can this race exist if the typical FE model is true? And it happens about every four years with multiple boats.  All the people involved are lying?

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Flat Earth Theory / Re: Around-the-World Sailing Races?

« on: May 21, 2020, 08:01:29 PM »

Ah, I love selective quotes.  Total Lackey is quoting from the accounts of Cook's second voyage.  Please read the entire section.  He was referring to what was called then "field ice" = floating pieces of ice of varying sizes, nowadays called pack ice.  Cook went on to lament that the ice prevented him from sailing further south, and he speculated that beyond the pack ice lay a land which contained the not-yet-discovered South Pole.  Keep in mind that from the deck of a ship all you can see is to about 8 miles away under perfect clear sky conditions.  After that it's over the horizon.  So he turned around and headed north.  Thus is all from page 160 of the accounts of Cook's second voyage.  Sure doesn't sound like a guy who just found an ice wall that stretched endlessly around the entire flat earth, now does it?

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Flat Earth Theory / Re: Around-the-World Sailing Races?

« on: May 20, 2020, 06:51:13 PM »

Okay, I'm the one who started this.  This will be my final input.  But I'd like to make a few last points/clarifications:

1) I guess in the beginning I should have defined terms.  What I mean my "celestial navigation" is the final product of years of smart people working on this problem of using a sextant, a chronometer, and carefully developed tables or computers/calculators to find your position at sea.  The math required to do so is spherical trigonometry.  This is a fact.  Spherical trig is used because you are finding your position on a sphere. So, my definition of "celestial navigation" is the common system in worldwide use before the advent of electronic navigation systems like GPS, LORAN, DECCA, etc.
2) It is true that people have been using other kinds of celestial navigation for millennia.  The indigenous navigators of the South Pacific are particularly famous.  (Read the book about them: "We, the Navigators" by David Lewis - fascinating!)  Even in more modern ages there is a "lunar method" that does not require a chronometer.  The famous sea captain, Joshua Slocum, who was the first person to sail single-handed around the world in 1895-98 reportedly used that method, but I understand it is extraordinarily complicated.  However Slocum spent years before that famous voyage as a regular sea captain, so he had the experience & knowledge.
3) The example I gave of a large spherical triangle based on the pole and the equator was just that, an example.  One easily imagined in someone's mind.  In real life celestial navigation involves solving many different spherical triangles, some big, some small.  There are an infinite number of possible spherical triangles on the surface of a sphere, just like there are an infinite number of potential flat triangles on a plane.  I was just giving an example.  Don't get hung up on that.
4) It's also true that navigators use flat maps (charts) at sea, not a globe.  BUT, BUT, BUT that's because flat maps are much more convenient, AND over the scale of the typical marine chart the differences between a flat Mercator projection chart and the real spherical world are trivial.  But that is for the same reason that when you are standing on shore looking at the horizon - it looks flat.  It's NOT FLAT!  But the curvature is so subtle that the human eye and brain cannot detect it.  Similarly over the distances covered by a typical chart "correcting" for the fact that this is a flat representation of a small portion of a sphere is just unneeded.  BUT for crossing entire oceans, then it matters.  You then use a great circle course, which when plotted on a standard Mercator projection chart ends up looking like a "longer" curved line, but in the real world is the shortest distance.  The ONLY great circle routes when plotted on a Mercator chart are still straight lines are at the Equator headed due east or west or when traveling absolutely due north/south along a line of longitude.  All other great circle routes on a standard chart will look like a curved line.  In an earlier post I mentioned Charles Lindbergh.  Before his historic New York to Paris flight, he went to the main New York City public library and stretched a string on a very large globe they had there (I understand it was 4-5 feet in diameter) between New York and Paris.  Since he could not take a globe with him in his airplane, he took careful notes as to where he needed to be for each stage of his flight to follow a great circle course.  And in almost every book I've read about Lindbergh and his flight, there is a chart of his course across the Atlantic plotted on a Mercator projection chart of the Atlantic ocean.  The course looks like a curved line.  In reality, up in the air, it was not - it was a straight-as-he-could-do-it straight Great Circle line to Paris.
4) And again, all those crusty old sea captains who had to do celestial never fessed up?  And none of them ever found the "ice wall" circling the flat earth?  And since the southern oceans were at one point heavily sailed by whalers (thankfully that's over) you think one of them would have noticed an endless wall of ice?
5) And I need at least mention another inconvenient fact about celestial that I haven't yet mentioned.  Celestial is also based heavily on a bunch of smart astronomers figuring out precisely where the "geographic point" is for all the celestial bodies used for navigation are at any given time.  The celestial bodies are: sun, moon, major planets, and about 20 of the brightest stars.  The principle is using the angle measured by a sextant and a chronometer to calculate where you are compared to the geographic point of the celestial object you are using at that exact point in time.  (Given the rotation of the Earth, for every 4 seconds you are off on your time measurement your calculated position is off by a mile of longitude.)  The geographic point is where the celestial object would be directly over your head.  If the object is low on the horizon from the navigator's perspective the geographic point could be thousands of miles away.  That's not a problem, but then the use of spherical trig is mandatory or else the error involved would make the effort pointless.  Plus, that entire process of calculating and then incorporating the geographic point for all those celestial bodies into the tables or calculators/computers used is also based on the earth being a globe.  None of those astronomers are flat-earthers.  So geographic points are yet another critical part of celestial navigation that relies on the Earth being a sphere. 
6) To the FE people who have replied, it strikes me that none have you have carefully thought about what I and others have said about celestial navigation.  Your response seems to be the intellectual equivalent of putting your fingers in your ears and yelling "Na-Na-Na-Na" when someone is telling you something you don't want to hear. 
7) And no FE responder has explained why the distances required for an around-the-world sailing race would be 2-3 times longer based on the common FE model than they really are. And, yes, the sailors would notice that sort of thing. 
Finally - Celestial navigation works.  It's worked for centuries.  Long before NASA and at least since the 1760s by every sea captain from every seafaring nation, regardless of politics, religion.  The math required is spherical trigonometry.  It's spherical trigonometry because the earth is a sphere.  No one would bother using the complexity of spherical trig if it wasn't needed.  Be intellectually honest and get over it.  I'm going sailing.

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Flat Earth Theory / Re: Around-the-World Sailing Races?

« on: May 18, 2020, 03:43:19 PM »

Okay, I gave the illustration of an equilateral triangle on a sphere with three 90 degree angles to contrast to the standard flat equilateral triangle of three 60 degree angles just to illustrate the difference and to make sure readers knew what I was talking about.  Never-the-less spherical trig is indeed different than flat trig, and celestial navigation is based on spherical trig.  It uses spherical trig to calculate the angles relative to where a celestial body is directly over the surface of the earth at the time you are taking the sight.  (In other words the place you would be if the celestial body you are using was straight up over your head.) If that were the case all the time then celestial would be absurdly easy. Since the celestial object (sun, moon stars, planets) is almost never directly over your head, you use a sextant to measure the angle that object appears above the horizon.  Celestial then uses that angle with spherical trig to determine your "line of position".  (It's a movie myth that a single sextant sight gives you an "X marks the spot" position.  Except for the famous "noon sight" you get a short line that you are somewhere on that line.  There are other ways to then upscale that to a more precise position.).  And in reality nobody does the math themselves.  You use either books of detailed tables or later computer/calculators to do that math.  BUT the reality is that the system is indeed based on spherical trig, not flat trig.  The respondent's statement that you don't need spherical trig to navigate, that it's "nonsense" is simply not true for celestial navigation.  it is true for navigating on a chart, within sight of land, to work out your bearing to a lighthouse for example.  Flat trig works fine for that, because the distances involved are so short that the "needed correction" for being on the surface of a sphere is trivial.  It's the same reason you can use a flat paper chart to navigate along the coast.  Technically that flat chart is slightly "wrong" since you cannot accurately depict a sphere on a flat paper, but again for the distances involved the "error" is trivial.  But out on the open ocean, trying to determine your position is an entirely different matter.  Prior to GPS, you needed celestial navigation to do that. And without the spherical trig behind celestial, it would fail. And it doesn't fail - it works.  It's worked for hundreds of years.  If the earth was flat, then the math for celestial would be standard flat trig, but it's not.  There would be no need to calculate spherical triangles to determine your position since you are on a alleged flat surface.  This is a simple non-disputable fact.

I feel I speak with some degree of real-world expertise about celestial navigation.  Anybody out there who has used celestial who disagrees with me?

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Flat Earth Theory / Re: Around-the-World Sailing Races?

« on: May 17, 2020, 10:44:28 PM »

Yes, indeed you would end up back at the pole on a FE with your proposed trip, BUT the flaw in that is that you have not made an equilateral triangle on your flat earth since the equator part of the trip is a curved line, a radius around the North Pole.  The math would then fail.  On a globe my route from pole to equator and back to the pole is a perfectly fine 90-90-90 equilateral spherical triangle.  Yours is a pie wedge. 

And so far, no one has answered why celestial navigation, based on spherical trigonometry, works if the earth is truly flat.  Plus the matching issue as to why sea captains don’t believe in a flat earth. 

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Flat Earth Theory / Re: Around-the-World Sailing Races?

« on: May 16, 2020, 12:23:59 AM »

One other brief comment about sailboats and hull speed. Sailors are warned that if they ever need to be towed by a powerful powerboat - to make absolutely sure the skipper of the powerboat understands the hull speed of the towed boat. Trying to exceed that speed puts tremendous loads on the tow rope and whatever it is attached to, and yes, there have been occasional reports of sailboats being swamped and lost because someone tried to greatly exceed the boat’s hull speed during a tow. They weren’t paying attention as their tow sunk behind them.

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Flat Earth Theory / Re: Around-the-World Sailing Races?

« on: May 16, 2020, 12:05:22 AM »

The slightly longer but still simplified explanation of hull speed is that the curved bottom of a sailboat can be viewed as an upside down airplane wing. On airplanes the curve points up, on sailboats down. As the boat moves through the water it creates “lift” downwards. The faster it goes the greater the down force, the deeper the boat sinks, and up goes the drag. There’s wave making issues too which limit the speed. And we’re only talking about the boat sinking down by a few inches but that’s enough to increase the drag to limit the speed. The standard formula is that the hull speed of most sailboats in knots is 1.34 times the square root of the waterline length.  My 34 foot (Overall) non-racing sailboat has a waterline length of about 25 feet, so her hull speed is 1.34 x sq rt(25) = 6.7 knots. Under perfect conditions I can get her up to about 7 knots but that’s it. (1 knot = 1.15 mph). High end racing yacht designers can use tricks to increase the hull speed past that formula - but not by much. Powerboats generally avoid the problem by skimming (planing) on the surface of the water, like continuously skipping a flat stone. And if the hull is really long and skinny (a ratio of length to beam generally greater than 20:1) other physics kicks in. Note: a real naval architect would be howling about my oversimplification. It ain’t simple.

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Flat Earth Theory / Re: Around-the-World Sailing Races? - Part 2

« on: May 15, 2020, 06:39:44 PM »

AS an experienced sailor, and knowing my beloved sailboat, Serenity, very well, I can tell without looking at the knotmeter a one knot difference in speed through the water.  And as others who have replied to my original post, looking at the common FE models would require distances that are at least 2 times farther than on a RE, and likely closer to three times farther to circumnavigate.  Please believe me that even ignoring GPS data, anyone with enough sailing experience to be doing a round-the-world race would be aware of the massively increased distance involved.  And monohull sailboats have a "hull speed" past which they cannot reasonably go faster.  This is based on the well-known physics of water itself and wave generation.  The oversimplified explanation is that as you push a displacement boat hull faster and faster it starts sinking deeper into the water, which greatly increases the drag until you reach a limit = the hull speed.  You just cannot make up that degree of distance increase.

My second question/puzzle for FE's is that I have the honor of being old enough to have been trained as a celestial navigator - using a sextant and an accurate watch to determine position at sea.  I was lucky enough that when I was in graduate school at Washington University in St. Louis I was able to take a whole semester long course in Celestial taught by a retired Navy officer navigator.  Since it was a semester long course we got heavily into the basic math involved.  In practice there are books of tables and now calculators/computers that do the math for you, but if you want as a FE believer to assume those books and computers are somehow "doctored" by NASA, my instructor made us do the math ourselves.  My final project was to write a computer program that calculated the "great circle route" between two points on the globe.  When Lindbergh wanted to calculate the great circle course (the shortest distance) for his historic flight from New York to Paris he had to stretch a string taut on a large globe at the New York City library before the flight and take careful notes as to where he should be at each stage of his flight. 

The math required for Celestial is called "spherical trigonometry", and you need a higher level scientific calculator or computer.  The simplest example I can give is that on a flat plane an equilateral triangle (all three sides are on the same exact length) has three angles of 60 degrees each.  However on a sphere an equilateral triangle is quite different, with three angles of 90 degrees each, not 60.  Imagine traveling on a sphere.  You start at the north pole and travel due south to the equator.  Once you reach the equator you turn due east or west (doesn't matter which), that's a 90 degree turn, and then travel the exact same distance as you did from the pole to the equator.  At that point you turn north again (another 90 degree turn) and travel back to the pole.  Once back at the pole again you will discover the angle between your departing and returning path is also 90 degrees.  Spherical trig has no trouble with calculating all sorts of triangles on the surface of a sphere.  Regular flat trig that we all learned in school won't work.  Likewise if we really are on a flat earth, then the math behind sextants wouldn't work, not even close.  But it works fine.  Not as good, and certainly not as easy as GPS, but gets you within about a mile of where you want to be, and for most purposes that's good enough.  And it's been used since the invention of a reliable chronometer (accurate clock at sea) in the 1760s.  Long before space flight, NASA or any other alleged conspirators.  Or do you think all those tens of thousands of crusty old sea captains were all part of a massive conspiracy to hide the flat earth secret for 260 years?  And not one of them ever fessed up about the "secret" he/she was keeping?

A FE answer please?

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Flat Earth Theory / Around-the-World Sailing Races?

« on: May 14, 2020, 07:27:13 PM »

I have a question for the FE community. I've searched through the forums, and while I've seen posts about circumnavigating the Antarctic continent, I've not found this topic.  If I've missed it - I apologize.  I'm a pretty serious offshore sailor.  Over 2018-19 I put 6,000 nautical miles on my sailboat.  Since 1968, about every 4 years there are around-the-world sailboat races.  Almost all leave from England.  Some are non-stop; some have a few stops at the obvious places.  The typical course is to leave England, head south to the Cape of Good Hope at the southern tip of Africa, next to Australia, then around Cape Horn at the southern tip of South America, then back to England.  There's a great documentary movie, entitled "Maiden", about the first all-female crew to accomplish this grueling feat in 1989.  Using the FE model that I typically see, the distances involved in this would be hugely greater than if the Earth is really spherical.  Given that racing sailboats only go about 15 mph on average, I would think that the participants would easily notice such a massive increase in the distances they have to travel.  How does this reality mesh with the FE model?

I also have a question about the spherical trigonometry mathematics needed to make nautical sextants work (and they do) for ocean navigation, but I'll save that for now. 

Thanks