[inquisitive]

There is no Flat Earth map.

You mean it is not possible to use measured distances to produce a map that shows the earth is flat.

[Tom Bishop]

There is no Flat Earth map.

You mean it is not possible to use measured distances to produce a map that shows the earth is flat.

The problem with creating a map and model is that those "measured distances" rely on a Round Earth coordinate system to compute a distance. No one has ever verified the accuracy of the distances computed from that coordinate system. No one has ever taken a tape measurer across the Atlantic to verify the spherical lat/lon distances, for example.

If we accept the round earth coordinate system as true, we might as well accept that the earth is round. The claim that GPS, or whatever Round Earth coordinate device, is true and accurate, is a positive claim brought to these discussions which must be demonstrated as accurate.

[mtnman]

If we accept the round earth coordinate system as true, we might as well accept that the earth is round.

This sums up FE belief. You can't accept that the Earth is round, so you must reject every article of evidence and science that conflicts with your belief.

Distances not verified. Can you honestly say that you believe all these planes have not verified distances and don't know how far they are flying each day. How you expect anyone to take anything you say seriously with claims like that?

[Tom Bishop]

This sums up FE belief. You can't accept that the Earth is round, so you must reject every article of evidence and science that conflicts with your belief.

Distances not verified. Can you honestly say that you believe all these planes have not verified distances and don't know how far they are flying each day. How you expect anyone to take anything you say seriously with claims like that?

How does the pilot know that the output from the round earth coordinate system is exactly true?

[mtnman]

This sums up FE belief. You can't accept that the Earth is round, so you must reject every article of evidence and science that conflicts with your belief.

Distances not verified. Can you honestly say that you believe all these planes have not verified distances and don't know how far they are flying each day. How you expect anyone to take anything you say seriously with claims like that?

How does the pilot know that the output from the round earth coordinate system is exactly true?

Because they fly from point A to point B. They leave point A with known aircraft weight and fuel, they know the route, they know the speed, heading and fuel consumption of their aircraft, and they know when they land.

Do you REALLY think that pilots don't know that the distance they travel matches the expectation based on coordinates?

Have you ever been on a commercial flight where they couldn't forecast a landing time?

[xenotolerance]

 The pilot knows the distance is correct because the plane used the predicted amount of fuel. Because the flight took the predicted amount of time. Because the plane's GPS indicates the distance traveled.

See also, a thread on the same topic. It's a lock for proving the Earth is not flat, by Tom's own standards.

[Tom Bishop]

How does the pilot know that the amount of consumed fuel equates to a true distance traveled rather than a distance traveled according to the Round Earth coordinate system?

Equally questionable, how does the pilot know that the time of flight equates to distance traveled? Cruising speed? How did these airplanes get their cruising speed calculated? Based on a distance provided by a Round Earth coordinate system?

[inquisitive]

How does the pilot know that the amount of consumed fuel equates to a true distance traveled rather than a distance traveled according to the Round Earth coordinate system?

The round earth coordinate system has nothing to do with measured distances by an object travelling at a given speed for a given time.

DISTANCE = VELOCITY * TIME

[Tom Bishop]

How does the pilot know that the amount of consumed fuel equates to a true distance traveled rather than a distance traveled according to the Round Earth coordinate system?

The round earth coordinate system has nothing to do with measured distances by an object travelling at a given speed for a given time.

The plane would need to know how fast it is traveling.

Airspeed indicator devices are not accurate and are not used in navigation. It is not possible to create an odometer for an airplane to guess how fast it is moving through the air. It is measuring fluids traveling within fluids. The airspeed of fluids against the wings is only used in things like banking maneuvers.

Groundspeed indicators which measure against the ground (such as GPS) are based on a Round Earth coordinate system, and would produce a Round Earth result.

[mtnman]

Airspeed indicator devices are not accurate and are not used in navigation.

Please provide your reference for this claim.

[Tom Bishop]

Airspeed indicator devices are not accurate and are not used in navigation.

Please provide your reference for this claim.

See this exchange with Curious Squirrel:

I'll link you again that air speed is NOT measured by how much ground they cover, but by the speed of the plane through the air. As explained here the speed of a plane is measured based on the air it goes through, using standard nautical miles. If you wish to explain how a Flat Earth mile differs from a Round Earth mile, I'm all ears. But I'm not sure such a claim can hold water in any sort of honest debate.

Airspeed is not reliable, as the plane is traveling in fluids which are traveling within fluids. All instruments which measure how fast air is passing by the craft are unreliable. Your website directly states that it is considered rather useless and is not used in navigation.

Read this quote from your link:

Knowing TAS (True Airspeed) during flight is surprisingly useless - for navigation, ground speed is needed

Groundspeed is computed by measuring with some reference to coordinates based on a Round Earth model.

[xenotolerance]

That planes can navigate so well using 'round Earth coordinates' is evidence that their coordinates are correct, that their navigation models are correct, and that the Earth is not flat. Not sure why you keep bringing that up like it's supposed to help your argument; it doesn't.

[mtnman]

Airspeed indicator devices are not accurate and are not used in navigation.

Please provide your reference for this claim.

See this exchange with Curious Squirrel:

...

While I'm sure Curious Squirrel will be flattered to be your source material on this subject, I don't see where in that quote it is established that airspeed indicators are not used in navigation. If you want to make a claim that they are not the only source of navigation data, I would agree with that. But it is still nonsense that pilots have not confirmed distances based on conventional maps and charts.

[Shifter]

Perhaps most of this thread should be moved into the debate section.

[Tom Bishop]

That planes can navigate so well using 'round Earth coordinates' is evidence that their coordinates are correct, that their navigation models are correct, and that the Earth is not flat. Not sure why you keep bringing that up like it's supposed to help your argument; it doesn't.

So if a pilot can navigate between points with a Mercator map, the world is a Mercator map? 

[xenotolerance]

Yes.

It means the Mercator map is sufficiently accurate for navigation to be possible. Mercator maps are cylindrical projections of a sphere. Thus, the spherical model is accurate.

[GiantTurtle]

Air speed indicators are accurate to a degree, and while they are not used for navigation, they will give a reading that can confirm the shape of the earth.
Here is an article that shows a pilot claiming that an error of 6knots is outside of safe levels. http://rec.aviation.ifr.narkive.com/ISynE1Rf/airspeed-indicator-accuracy-tolerance
An inaccuracy of 6knots on a Boeing 747 at cruse speed is an error of just over 1%.

So yes you can't draw an accurate map based on flight speeds and time alone, but I think some of them would notice if they always had to fly twice as fast in one hemisphere than another.

[GiantTurtle]

That planes can navigate so well using 'round Earth coordinates' is evidence that their coordinates are correct, that their navigation models are correct, and that the Earth is not flat. Not sure why you keep bringing that up like it's supposed to help your argument; it doesn't.

So if a pilot can navigate between points with a Mercator map, the world is a Mercator map? 

If the round earth was correct then using a Mercator map would leave many planes running short of fuel. For example, flying across Africa would take three times as much fuel than Europe even though Europe is bigger on the projection.
But if you do fly across both Europe and Africa using the same amount of fuel then, yeah, I guess that is a good map.

[xenotolerance]

True. I am assuming one would account for the distorted distance shown on the map, as that is a well understood feature of Mercator projection.

[TropeADope]

How does the pilot know that the amount of consumed fuel equates to a true distance traveled rather than a distance traveled according to the Round Earth coordinate system?

The round earth coordinate system has nothing to do with measured distances by an object travelling at a given speed for a given time.

The plane would need to know how fast it is traveling.

Airspeed indicator devices are not accurate and are not used in navigation. It is not possible to create an odometer for an airplane to guess how fast it is moving through the air. It is measuring fluids traveling within fluids. The airspeed of fluids against the wings is only used in things like banking maneuvers.

Groundspeed indicators which measure against the ground (such as GPS) are based on a Round Earth coordinate system, and would produce a Round Earth result.

Tom how do you travel? Im going to assume you have been to somewhere new, that you don't have inherent knowledge of where everything is. How did you get from point A to point B? Can't use a map, MapQuest, Google, any sort of GPS, or any modern technology as it is all based on RE measurements.
So, how the hell did you get there and back? Also did you tell whoever was on the other end of the trip, "I'll get there when I get there because I have no clue as to how far it actually is."