The Flat Earth Society
Flat Earth Discussion Boards => Flat Earth Theory => Topic started by: jimster on May 23, 2021, 09:43:54 PM
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I was watching a battleship New Jersey youtube video that had a Viet Nam war vet talking about using the 5" inch secondary fire control computer.
https://www.youtube.com/watch?v=nUESPDkKEgA
The 16" guns fire control computer had earth curvature correction (explained in video below) The secondary fire control computer did not have earth curvature correction, range was too short. They came up with a rocket assisted round with 50% greater range. They had to correct for earth curvature manually.
Then I searched to find out more about how common is curvature correction for artillery, and I found that the US Army acknowledges flat earth!
https://www.facebook.com/129815299935/posts/flat-earth-changes-artillery-mathematicsby-monica-k-guthriefort-sill-okla-the-re/10156326388059936/
Sorry, had to do it, but seriously ... here is a good explanation of why all countries with artillery with more than 10 miles know whether the earth is curved.
https://www.youtube.com/watch?v=wKTvZ8azi5U
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Watch the first video from 2:00 to 3:30. After the test round was fired he does not say that the adjustments were made based on earth curvature/rotation calculations when the Pacific Fleet Admiral was standing behind him for the demonstration. Adjustments were made by the offset of the test round. Artillery does not make first round hits, and requires adjustment.
See: https://wiki.tfes.org/Coriolis_Effect#Artillery
Artillery is not accurate. Calculations for Coriolis may be applied in the initial firing table based on theory, but the guns are nonetheless always inaccurate and adjustments are required.
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He dry-labbed the correction factor instead of calculating it, but if the earth was flat, the gun would have been on target without the correction.
He also says the 16" guns did have the curvature calculation built in to the computer (actually a system of gears and cams, a mechanical analog computer.
The accuracy of artillery is well known, Aberdeen Proving Grounds had been doing this since forever, and testing weapons is a world-wide popular thing to do. Every major country tests artillery.
Coriolis was discussed in my web search someone said it was in the software, someone else said it was a tiny error, but I believe it causes a bearing error, and earth curve causes range error.
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Again, all you need for accuracy is to know the amount of "punch," each round has, the wind, and a simple quadratic equation which all work just fine on any FLAT x/y coordinate plane.
More RE sound and fury, signifying nothing.
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Again, all you need for accuracy is to know the amount of "punch," each round has, the wind, and a simple quadratic equation which all work just fine on any FLAT x/y coordinate plane.
More RE sound and fury, signifying nothing.
I'm personally not a trained artilleryman so I couldn't give you an exhaustive list of "all you need for accuracy", but I would have thought that, in addition to muzzle velocity (punch?), then mass, size and drag-coefficient of the shell, as well as air density, would be in there somewhere.
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Again, all you need for accuracy is to know the amount of "punch," each round has, the wind, and a simple quadratic equation which all work just fine on any FLAT x/y coordinate plane.
More RE sound and fury, signifying nothing.
I'm personally not a trained artilleryman so I couldn't give you an exhaustive list of "all you need for accuracy", but I would have thought that, in addition to muzzle velocity (punch?), then mass, size and drag-coefficient of the shell, as well as air density, would be in there somewhere.
"Punch," is inclusive of all the things you just mentioned.
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That is not the question. The questions is, given identical conditions, will the curve of the earth play a part in long range artillery aiming. Multiple countries have researched artillery aiming. My point is that artillery aimers think they need to consider the earth's curvature at long range. They go to great effort to test artillery accuracy and get the aim right. The people testing long range artillery know the shape of the earth as confirmed by real world testing.
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Again, all you need for accuracy is to know the amount of "punch," each round has, the wind, and a simple quadratic equation which all work just fine on any FLAT x/y coordinate plane.
More RE sound and fury, signifying nothing.
I'm personally not a trained artilleryman so I couldn't give you an exhaustive list of "all you need for accuracy", but I would have thought that, in addition to muzzle velocity (punch?), then mass, size and drag-coefficient of the shell, as well as air density, would be in there somewhere.
"Punch," is inclusive of all the things you just mentioned.
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So "punch", inherent to the shell as it leaves the factory, includes atmospheric air density on the day it is fired? How do they do that?
As jimster quite rightly says, "that is not the question", but I ask it again anyway to illustrate that, if your simplistic argument can't address the opposing values of "punch" ( the initial impetus given to the shell in the barrel), and the aerodynamic drag on the shell due to changeable atmospheric conditions over any-shape of Earth, how do you expect to persuade us of your flat/round insight?
Or is it all wrapped up in the "simple quadratic equations" that you have yet to define?
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What he is calling "punch" would be referred to as F (force) in physics class. If you know F, M (mass) and the angle of the barrel, and the force of gravity, the resulting trajectory will be a parabola described by a quadratic equation. And yes, that is the basic equation of a range finder. Let's agree to ignore the aerodynamics of the projectile (with cannon ball or artillery shell affect is minor), wind (calm day), corriolis (tiny effect), the point stands without the minor differences these would make.
Whatever the shape of the trajectory, that is not the issue. The issue is where is the target:
(https://i0.wp.com/mathscinotes.com/wp-content/uploads/2017/12/GoodIllustration.png?ssl=1)
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Jimster, you really ought to find out what the FEI board is for before posting in it.