28 Oct 15
Originally posted by twhiteheadNone of your anecdotal examples require a globe.
In reality, there are many good reasons for just about anyone to think the spherical model is valid based on their own direct observations. I for example have travelled across timelines and phone back home and asked what the time is, and confirmed for my self that the sun rises earlier in the east (Dar-es-Salaam in my case). I have also travelled further ...[text shortened]... so met someone who actually sailed around the world, but there I must just take his word for it.
28 Oct 15
Originally posted by PatNovakGo back and respond to the post I directed to you and in so doing, explain why a person must leave a particular point of latitude while engaging in longitude travel in order to obtain the shortest route (assuming no geographical barriers).
This is the whole point. A straight line between points on a sphere must go inside the sphere. And because a straight path cannot be taken on the surface of a sphere, the shortest path you can take between points on the surface is along a Great Circle.
Do you agree or disagree with a Great Circle being the shortest path on the surface of a sphere?
You're going to have a hard time doing so, because (as you can see from the math) the path in question caused the plane to travel an additional nearly 1600 miles north of its otherwise fairly straight path.
Originally posted by FreakyKBHNeither, I am just making sense which is more than can be said about you.
I'm not sure if you're lacking in imagination, simply being obstinate or some inexplicable combination of both.
Starting at Boston's Logan Airport at a latitude of 42.372524° one can EASILY stay at the same latitude across the entire US--- or the entire earth, for that matter--- without any deviation whatsoever, north or south.
I agree. I have not disputed that in any way shape or form.
You are fully aware that this in no way, shape or form represents what has been discussed.
You do understand English I hope? If that is not what was being discussed then what is being discussed?
The question considered whether or not a person could conceivably remain on the same latitude even while making longitude changes.
No, it wasn't. this is the first I am hearing of that 'question' and it is not the question I was responding to. To claim otherwise is a blatant lie on your part. And your post is there for anyone to check an verify that you are lying.
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28 Oct 15
Originally posted by FreakyKBHSimple.
Go back and respond to the post I directed to you and in so doing, explain why a person must leave a particular point of latitude while engaging in longitude travel in order to obtain the shortest route (assuming no geographical barriers).
You're going to have a hard time doing so, because (as you can see from the math) the path in question caused the plane to travel an additional nearly 1600 miles north of its otherwise fairly straight path.
Imagine that you are 1 degree away from the north pole. [~110km, we will specify
exactly 110km for the purpose of this thought experiment]
And you want to travel to a different point that is at the exact same latitude [89 degrees North]
as you but on the opposite side of the north pole.
Question. Which route is quicker/shorter to take, the one strait across the pole? Or
going around the pole staying on the same latitude?
The answer is obvious, the shortest route is over the pole.
Now move those points [keeping them at the same latitude] 1/8th of the way around the
pole each so that they now have 1/4 of the circumference between them instead of 1/2.
Now again, which is the shortest route...
Across the circle? or around the circumference?
Again, the answer is obviously across the circle... But not strait across, the correct shortest
path will be a curved line [as viewed from above the pole] as you take into account the upward
bulge due to Earth's curvature. This line is a great circle that will cross the latitude at an angle
depending on where the two points on the latitude are, and what that latitude is.
The closer the latitude is to the equator, the shallower the angle will be.
At the equator the equator IS the shortest line between two points on the equator.
Above the equator the shortest line will bulge north, below it will bulge south.
Originally posted by googlefudgeSo simple, in fact, that you aren't able to address the example(s) which have already been brought forth.
Simple.
Imagine that you are 1 degree away from the north pole. [~110km, we will specify
exactly 110km for the purpose of this thought experiment]
And you want to travel to a different point that is at the exact same latitude [89 degrees North]
as you but on the opposite side of the north pole.
Question. Which route is quicker/shorter to take ...[text shortened]... the equator.
Above the equator the shortest line will bulge north, below it will bulge south.
Take either TPE to LAX or BOS to SEA and make your point accordingly.
The closer the latitude is to the equator, the shallower the angle will be.
I'm sure you have a formula for that.
Nonetheless, let's see if that statement holds true in the examples.
In the TPE to LAX flight, the path requires a 1600-1750 mile northward divergence prior to traveling east to the destination.
Beginning point is along 25° latitude.
Ending point is along 33° latitude.
Normal path takes the vehicle north to 50° latitude--- or, as stated, nearly 1600 miles off the east-west path which is within 8° of each other.
EDIT: Although I have been able to find some paths which are as low as mid-40° latitude for this flight.
Conversely, BOS is on 42° latitude, ends up at SEA on 47° for a 5° northward variation.
Normal flight pattern takes the vehicle north to ~48° around Montana and then slowly back south to finish in SEA.
And the ~ in front of the 48° is meant to indicate the lower portion of that latitude, generally in the two's.
If my calculations are correct--- and I'm pretty sure they are--- latitudes of either 25° or 33° are both considerably closer to the equator than either latitude of 42° or 47° and yet the swing from 25° is a whopping 25° difference (representing the stated 1600-1750 additional miles), whereas the northward excess on the BOS to SEA is ~1° for a swing of ~70 miles.
You were saying?
28 Oct 15
Originally posted by twhiteheadI agree. I have not disputed that in any way shape or form.
Neither, I am just making sense which is more than can be said about you.
[b]Starting at Boston's Logan Airport at a latitude of 42.372524° one can EASILY stay at the same latitude across the entire US--- or the entire earth, for that matter--- without any deviation whatsoever, north or south.
I agree. I have not disputed that in any way shape or ...[text shortened]... atant lie on your part. And your post is there for anyone to check an verify that you are lying.[/b]
Well, of course you do.
Now.
However, you seemed to be of a different mind when I asked you:
"Is he able to keep a trajectory which does not require any northern deviation greater than his final destination?"
You responded quite monosyllabically:
"No."
Or again, in the same post, you were asked:
"Is he able to refrain from a trajectory no further north than his final destination?"
You articulated a little more on your response to this one:
"No."
So you can understand how a reasonable person might think you're just taking the piss at this point.
No, it wasn't. this is the first I am hearing of that 'question' and it is not the question I was responding to. To claim otherwise is a blatant lie on your part. And your post is there for anyone to check an verify that you are lying.
The summation in the post to which you are responding here is nothing more than a rewording of the concept you have already acknowledged understanding.
To wit:
Originally posted by twhitehead
27 Oct '15 12:36 / 1 edit
"On a globe, one would not fly due east as doing so is not the shortest path."
You were saying something about someone lying...?
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28 Oct 15
Originally posted by FreakyKBHI chose an example that makes what is going on obvious, as a starting point.
So simple, in fact, that you aren't able to address the example(s) which have already been brought forth.
It's much more sensible to use obvious simple examples when trying to understand
a basic concept rather than jump in with a more complex messy one.
However if you are going to insist on looking at this particular example...
Open [or download and install] Google Earth.
Use the ruler function to draw a strait line from Boston to Seattle.
Then tilt the Earth so that this line appears strait, ie you are directly above that line looking down.
What you will notice looking at the Earth like this is that the lines of latitude appear curved.
Now zoom/pan/tilt till the nearest lines of latitude appear strait, and what you will see is that
the line you drew between Boston and Seattle looks curved.
What this tells you is that ALL 'strait' lines on the surface of a sphere can appear to be strait or curved
depending on the angle at which you view them.
Now Google Earth is drawing the shortest line between the two points so why would that line 'bow northwards'
'adding distance'?
Because it's REDUCING the extra distance required because the Earth bulges OUTWARDS in the
third spacial dimension you don't get on 2d maps.
Which is why you use a globe [or digital equivalent] and not a flat distorted projection map.
28 Oct 15
3 edits
The Earth is (mostly) spherical. To go from point A to point B most directly does not involve following the latitude lines. Look at a globe some time. Or look at a map of one of the poles with latitude lines drawn in.
http://www.mgaqua.net/AquaDoc/Projections/img/Polar%20Stereographic.jpg
There are probably other variables like weather, politics, terrain etc but the above fact is quite well known.
What is the most direct route from Finland to Alaska? Perpendicular to latitude lines, over the North Pole.
http://cdn-www.airliners.net/uf/111795/middle/phpsUWcIb.gif
Originally posted by FreakyKBHNo. I cannot understand how a reasonable person might think that. Why should a monosyllabic answer cause a reasonable person to think I am 'just taking the piss'? The answers were clear and to the point. And correct.
So you can understand how a reasonable person might think you're just taking the piss at this point.
The summation in the post to which you are responding here is nothing more than a rewording of the concept you have already acknowledged understanding.
No, it is not. (four syllables).
The post I originally responded to clearly asked about what would happen if someone walked (whether or the ground or in the air) in a straight line. It did not as you falsely claim ask about sticking to a line of latitude which everyone knows is not a straight line. Or are you really that delusional?
28 Oct 15
Originally posted by googlefudgeI appreciate your effort at attempting to clarify, but I think it makes more sense to stay with what is already on the table.
I chose an example that makes what is going on obvious, as a starting point.
It's much more sensible to use obvious simple examples when trying to understand
a basic concept rather than jump in with a more complex messy one.
However if you are going to insist on looking at this particular example...
Open [or download and install] Google Earth. ...[text shortened]...
Which is why you use a globe [or digital equivalent] and not a flat distorted projection map.
I've had Google Earth installed on my computer (and phone) since it was first made available.
It's not really too helpful for these questions, since it presumes a globe--- although there is some light shed on some of the issues.
For instance, a globe model presents some very difficult obstacles when it comes to distances and flight paths below the equator.
But I don't want to muddy the waters more with even further considerations.
Let's focus on the problems presented at this point, please.
28 Oct 15
Originally posted by twhiteheadNo, it is not. (four syllables).
No. I cannot understand how a reasonable person might think that. Why should a monosyllabic answer cause a reasonable person to think I am 'just taking the piss'? The answers were clear and to the point. And correct.
[b]The summation in the post to which you are responding here is nothing more than a rewording of the concept you have already acknowledg ...[text shortened]... line of latitude which everyone knows is not a straight line. Or are you really that delusional?
Keep that calculator.
You're likely going to need it.
The post I originally responded to clearly asked about what would happen if someone walked (whether or the ground or in the air) in a straight line. It did not as you falsely claim ask about sticking to a line of latitude which everyone knows is not a straight line.
I get it: you're upset because you've realized your position is untenable.
It happens.
There is no "clearly" to the situation as you have reframed it.
I even helped you out by quoting the original question:
"Is he able to keep a trajectory which does not require any northern deviation greater than his final destination?"
Do you see those emboldened and italicized words with quotation marks just above this sentence you are reading now?
That is the sentence I originally put to you, to which you responded with the one word, "No."
The question asked if one could travel, altering their line of longitude (in this case, east to west) without deviating (in this case, more north) in excess of the latitude of the final destination.
I asked the question again with another parameter, which essentially did nothing to the original question other than move the traveler further from the surface of the earth, and you also responded with the one word, "No."
Or are you really that delusional?
Come, come, now.
We can both see you're the one having the connection issues.
28 Oct 15
Originally posted by FreakyKBHI am not upset. On the contrary, I am having a good laugh at your expense.
I get it: you're upset because you've realized your position is untenable.
It happens.
There is no "clearly" to the situation as you have reframed it.
It is clear to everyone but you.
I even helped you out by quoting the original question:
But you quoted it out of context. Earlier in the same post you stated that he was "taking the most direct path possible."
That is the sentence I originally put to you, to which you responded with the one word, "No."
And my answer was, and remains, correct. And it remains the case that the question I was responding to was not the question you later falsely claimed I was responding to.
The question asked if one could travel, altering their line of longitude (in this case, east to west) without deviating (in this case, more north) in excess of the latitude of the final destination.
No, it did not. It asked if he could do so whilst simultaneously taking the most direct path possible.
Come, come, now.
We can both see you're the one having the connection issues.
Try taking a poll on that and I think you will fail to find anyone who thinks you are not either totally delusional or trolling.
28 Oct 15
Originally posted by FreakyKBHThat's because your examples are designed to create the maximum confusion. This is a matter of elementary geometry. The shortest route from the north pole to any point on the earths surface is to face the right way and then head south. That is one of the great circles. If one rotates the great circle around the Earth's centre so it passes through both airports that will be the shortest route by rotational invariance. The route you are advocating is not a great circle. It is a longer path.
So simple, in fact, that you aren't able to address the example(s) which have already been brought forth.
Take either TPE to LAX or BOS to SEA and make your point accordingly.
[b]The closer the latitude is to the equator, the shallower the angle will be.
I'm sure you have a formula for that.
Nonetheless, let's see if that statement holds true in ...[text shortened]... eas the northward excess on the BOS to SEA is ~1° for a swing of ~70 miles.
You were saying?[/b]
There are a number of reasons why internal airlines might not take the shortest distance, including navigational simplicity, avoiding certain airspace, and air traffic congestion. There's no point in talking about airline's routes unless you know why they've taken that route.
Originally posted by FreakyKBHtwhitehead said: "So Freaky, now that you have demonstrated that you know nothing about maps, can't use relevant websites and cant even get your figures or story right when you post, why don't you just tell us the punchline? What was all this mean to be about before your plan went up in flames?"
Whoa. Your insight is dazzling. As I have concentrated my arguments to numbers and what can be demonstrated (mistakes on my part notwithstanding), your contention how there will be a deference to some subjective or arbitrary standard(s) makes exactly zero sense. Not that I would tell another how to play it, but if you wish to get in the arena, by all means ...[text shortened]... n the sidelines taking pot shots at the players contributes nothing more than unnecessary noise.
And I offered a possible explanation, that's all.