Disproving aviation's notion of a curved world

As a student pilot, I am frequently exposed to scientific evidence of the world taking on a spherical shape. There is one such example that i am at loss to explain after reading your FAQ section. In aviation, we use radio navigation aids known as VORs, which operate on the Very High Frequency spectrum. These energy waves propagate outwards from ground stations, and due to the energy of these waves, are only transmittable by direct line of sight. This means, in simple terms, you have to be able to "see" the ground station in order to receive information from it. Consider the example of being off the coast of Australia and tracking toward Sydney airport from New Zealand. This approach is flown fully over water, which obviously is all at an elevation of 0 feet. If the aircraft is at 5000ft above sea level, the declared (and proven) range of the VOR is approx 60 miles, whereas at 10,000ft, the range is double that. With no terrain impeding the wave propagation, and no interference of any sort from the ocean surface, how can the range change on a flat Earth? If, for arguments sake, the earth was curved, the range would obviously change with altitude, as the higher you are, the further away your visible horizon is. If the earth was flat, VOR range would be infinite, as long as there is no terrain blocking the waves. It is important to note that the power of a VOR transmitter does not affect range, over any reasonable distance. How can this be explained??

As a student pilot, I am frequently exposed to scientific evidence of the world taking on a spherical shape. There is one such example that i am at loss to explain after reading your FAQ section. In aviation, we use radio navigation aids known as VORs, which operate on the Very High Frequency spectrum. These energy waves propagate outwards from ground stations, and due to the energy of these waves, are only transmittable by direct line of sight. This means, in simple terms, you have to be able to "see" the ground station in order to receive information from it. Consider the example of being off the coast of Australia and tracking toward Sydney airport from New Zealand. This approach is flown fully over water, which obviously is all at an elevation of 0 feet. If the aircraft is at 5000ft above sea level, the declared (and proven) range of the VOR is approx 60 miles, whereas at 10,000ft, the range is double that. With no terrain impeding the wave propagation, and no interference of any sort from the ocean surface, how can the range change on a flat Earth? If, for arguments sake, the earth was curved, the range would obviously change with altitude, as the higher you are, the further away your visible horizon is. If the earth was flat, VOR range would be infinite, as long as there is no terrain blocking the waves. It is important to note that the power of a VOR transmitter does not affect range, over any reasonable distance. How can this be explained??

Welcome to the forum. 73% of the members here are like you. They know the earth is round. The other 27% are the FE(flat earth) members. You will get strange answers if any. I worked as a electronic and communication technician for 25 years at air traffic control center so I know exactly what your are talking about. They will come up with ideas that are totally observed. That is because they have no scientific knowledge of the laws of physics. If they did this site would not exist. I am her to go past their theories and to study their minds to how that got to be this way. I have learned many thing about them. I do respect them and try not to claim them as nuts or crazy. I won't say any more for now. Good luck. You can message me any time. I am am here 5 to 7 hours a day.

I do respect them and try not to claim them as nuts or crazy.

Typical!

Quote from: Starman on March 18, 2014, 06:17:13 PM

I do respect them and try not to claim them as nuts or crazy.

Typical!

I can if you want.

At higher altitudes, the air is less dense and therefore, radio signals and light can more easily travel through.  That is why you can see farther and receive radio signals from more distant places why you are flying higher than you would at a lower altitude.   

Quote from: sciencebitch on March 18, 2014, 06:01:06 PM

As a student pilot, I am frequently exposed to scientific evidence of the world taking on a spherical shape. There is one such example that i am at loss to explain after reading your FAQ section. In aviation, we use radio navigation aids known as VORs, which operate on the Very High Frequency spectrum. These energy waves propagate outwards from ground stations, and due to the energy of these waves, are only transmittable by direct line of sight. This means, in simple terms, you have to be able to "see" the ground station in order to receive information from it. Consider the example of being off the coast of Australia and tracking toward Sydney airport from New Zealand. This approach is flown fully over water, which obviously is all at an elevation of 0 feet. If the aircraft is at 5000ft above sea level, the declared (and proven) range of the VOR is approx 60 miles, whereas at 10,000ft, the range is double that. With no terrain impeding the wave propagation, and no interference of any sort from the ocean surface, how can the range change on a flat Earth? If, for arguments sake, the earth was curved, the range would obviously change with altitude, as the higher you are, the further away your visible horizon is. If the earth was flat, VOR range would be infinite, as long as there is no terrain blocking the waves. It is important to note that the power of a VOR transmitter does not affect range, over any reasonable distance. How can this be explained??

Welcome to the forum. 73% of the members here are like you. They know the earth is round. The other 27% are the FE(flat earth) members. You will get strange answers if any. I worked as a electronic and communication technician for 25 years at air traffic control center so I know exactly what your are talking about. They will come up with ideas that are totally observed. That is because they have no scientific knowledge of the laws of physics. If they did this site would not exist. I am her to go past their theories and to study their minds to how that got to be this way. I have learned many thing about them. I do respect them and try not to claim them as nuts or crazy. I won't say any more for now. Good luck. You can message me any time. I am am here 5 to 7 hours a day.

My experience has been about the same as starman. I worked at an air route traffic control center for 38 years on communications, radar and computer systems so I know what you are talking about. You will see some absolutely bizarre and goofy answers from FE's.

I won't go in to all the details, but check out my thread on "Ham Radio Measurements of the Distance From The Earth to the Moon" to see what I mean. ( I am also a licensed amateur radio operator as well as having held a commercial radio license.)

I am also an amateur photographer and FE's exhibit the same kind  of posts indicating a lack of even the basics of exposure, lenses, etc.

Like starman I won't say any more for fear of this being considered "low content" posting. I'm not on as regularly as starman. Some times I am on for  several hours but I may not be on for days at a time. You can also message me any time.  So good luck. Stick around for the entertainment value alone, but thanks to the preponderance of RE's you  may also learn a lot of evidence and facts from other RE's. I have. Welcome to the club !

My signature line says it all.  I will admit it's not original. I just paraphrased an old line that Billy Rose originated.LOL.

Well for RE  that claim to know their physics with radio waves. Air density plays a big part. Your not transmitting in a F-IN vacuum.  Atmospheric conditions have a big  influence on radio waves.       

Air density (ionosphere aside) has zero effect on radio waves bellow 10GHz (only some minor refraction). Try other explanation.

Air density (ionosphere aside) has zero effect on radio waves bellow 10GHz (only some minor refraction). Try other explanation.

This is a well known fact. Weather factors such as fog, clouds ,etc. will have some effect but it has been proven the atmosphere has little effect. There is no effect on the speed of radio waves also as some FE's will claim.

jroa's statetment is also ridiculously fallacious. No matter how high you go in  an aircraft you are always going to have to penetrate the "higher density" of lower altitudes  between you and the radio station and even if there was an effect of going higher this would have no effect . The aircraft is in the air above the station and the station is on the ground below the aircraft and there is nothing in between them but air.

Incidentally VOR by its very definition of "Very High Frequency Omni Range" indicates it operates on frequencies which are line of sight  and the range is limited by the curvature of the earth. Even sciencebitch knows this, but apparently FE's do not. (108-117.95 MHZ)

Incidentally most of other radio operations, such as the amateur radio repeater stations are also limited to their range due to the curvature of the earth and the frequencies used such as in the 2 Meter (144-148 MHZ) amateur radio band. The higher the antenna, the longer the range.


There is a simple formula to determine the distance to the horizon. The higher the altitude the longer the distance. Of course FE is going to say this is just a formula made up by some RE scientist to conform to the so-called "Round Earth Theory."

If the earth was truly flat, there would be no need for anything other than one radar system, one VOR and one communications system for air traffic control for the whole world. There would be no need for microwave relay systems either. The list could go on and on......

Actually atmospheric conditions do play an important role in electromagnetic wave propagation.

Atmospheric inversion layers (most commonly temperature inversions) will refract electromagnetic waves of >= 90 MHz over the line of sight optical horizon due to the higher pressure of warmer air having a higher refractive index.

The result would seem as if the wave is traveling faster in lower density higher altitude air overtaking the wave portion in higher density lower altitude air, but in reality it is being refracted.

Radar and other technologies can take advantage of this phenomenon known as tropospheric ducting.

To prove the curved Earth theory you would have to place the VOR station at a height where there is no line of sight terrain interference, and know exactly how the signal is radiated, ie. what angle to the horizontal, power, range etc. They are not set up to accommodate close range reception, and so, to keep things simple, just draw a line at an angle, say 10/20 degrees upwards from the point where the station is, and you can easily see that the higher you go, the further the apparent range.

Actually atmospheric conditions do play an important role in electromagnetic wave propagation.

Atmospheric inversion layers (most commonly temperature inversions) will refract electromagnetic waves of >= 90 MHz over the line of sight optical horizon due to the higher pressure of warmer air having a higher refractive index.

The result would seem as if the wave is traveling faster in lower density higher altitude air overtaking the wave portion in higher density lower altitude air, but in reality it is being refracted.

Radar and other technologies can take advantage of this phenomenon known as tropospheric ducting.

You are talking about ducting. It happens only on certain time a year. The lower frequencies below 30 Mhz will reflect on the ionosphere all the time. At those frequencies weather has no effect because the wavelength are to long compared to water in the air.

To prove the curved Earth theory you would have to place the VOR station at a height where there is no line of sight terrain interference, and know exactly how the signal is radiated, ie. what angle to the horizontal, power, range etc. They are not set up to accommodate close range reception, and so, to keep things simple, just draw a line at an angle, say 10/20 degrees upwards from the point where the station is, and you can easily see that the higher you go, the further the apparent range.

It is a lot more complicated than that. Radio waves have a direct effect on the surface it on. For example the higher you place an antenna above the ground the lower the main lobe will drop. It would be almost impossible to use that method to test the curvature of the earth.

Case rested?

Case rested?

I am on your site but that method would not work. Using laser beams would be a better way to prove that notion. You could have a big white surface on a ship and have it sail out at sea. With a fixed laser on the land you would sail and see that the laser on the white surface will be getting lower and lower. It would not be easy. The curvature is about one foot per 6400 feet.

Quote from: 391MultiVac611 on April 09, 2014, 11:42:56 AM

Actually atmospheric conditions do play an important role in electromagnetic wave propagation.

Atmospheric inversion layers (most commonly temperature inversions) will refract electromagnetic waves of >= 90 MHz over the line of sight optical horizon due to the higher pressure of warmer air having a higher refractive index.

The result would seem as if the wave is traveling faster in lower density higher altitude air overtaking the wave portion in higher density lower altitude air, but in reality it is being refracted.

Radar and other technologies can take advantage of this phenomenon known as tropospheric ducting.

You are talking about ducting. It happens only on certain time a year. The lower frequencies below 30 Mhz will reflect on the ionosphere all the time. At those frequencies weather has no effect because the wavelength are to long compared to water in the air.

Yes I'm talking about ducting, which is why I said ducting.  This phenomenon does affect RADAR.  I never mentioned ionospheric effects.  What is your point?

To prove the curved Earth theory you would have to place the VOR station at a height where there is no line of sight terrain interference, and know exactly how the signal is radiated, ie. what angle to the horizontal, power, range etc. They are not set up to accommodate close range reception, and so, to keep things simple, just draw a line at an angle, say 10/20 degrees upwards from the point where the station is, and you can easily see that the higher you go, the further the apparent range.

None of that makes any sense. In my example I clearly explained that there is no terrain interference, since the VOR sits at Sydney Airport (on the coast) and propagates over the ocean (flat). I would like a diagram of your 10/20 degree principle, because I think if you drew it you might realise it makes no sense.

To prove the curved Earth theory you would have to place the VOR station at a height where there is no line of sight terrain interference, and know exactly how the signal is radiated, ie. what angle to the horizontal, power, range etc. They are not set up to accommodate close range reception, and so, to keep things simple, just draw a line at an angle, say 10/20 degrees upwards from the point where the station is, and you can easily see that the higher you go, the further the apparent range.

Oops, ^Horizontal

Diagram isn't to scale, but clearly, the higher you're flying the sooner the station will be visible over the horizon. This is what's observed in reality. I put in the 10 and 20° lines you mentioned, but I'm not sure what their purpose is. Could you explain?

Well for RE  that claim to know their physics with radio waves. Air density plays a big part. Your not transmitting in a F-IN vacuum.  Atmospheric conditions have a big  influence on radio waves.       

It depends on the frequency. At frequencies below 30Mhz it has no effects. As the frequency gets higher it will have some effects. If you go very high it will more. So specify what frequencies you are talking about to say air density effects it.

Quote from: 391MultiVac611 on April 09, 2014, 11:42:56 AM

Actually atmospheric conditions do play an important role in electromagnetic wave propagation.

Atmospheric inversion layers (most commonly temperature inversions) will refract electromagnetic waves of >= 90 MHz over the line of sight optical horizon due to the higher pressure of warmer air having a higher refractive index.

The result would seem as if the wave is traveling faster in lower density higher altitude air overtaking the wave portion in higher density lower altitude air, but in reality it is being refracted.

Radar and other technologies can take advantage of this phenomenon known as tropospheric ducting.

You are talking about ducting. It happens only on certain time a year. The lower frequencies below 30 Mhz will reflect on the ionosphere all the time. At those frequencies weather has no effect because the wavelength are to long compared to water in the air.

Ducting happens 100% of the time over water. My job is to identify and extrapolate surface and elevated ducts. I'm sitting at my workstation now and I can tell how much of a duct exists in the atmosphere for any location on earth in real time.

Quote from: Starman on April 11, 2014, 06:36:25 AM

Quote from: 391MultiVac611 on April 09, 2014, 11:42:56 AM

Actually atmospheric conditions do play an important role in electromagnetic wave propagation.

Atmospheric inversion layers (most commonly temperature inversions) will refract electromagnetic waves of >= 90 MHz over the line of sight optical horizon due to the higher pressure of warmer air having a higher refractive index.

The result would seem as if the wave is traveling faster in lower density higher altitude air overtaking the wave portion in higher density lower altitude air, but in reality it is being refracted.

Radar and other technologies can take advantage of this phenomenon known as tropospheric ducting.

You are talking about ducting. It happens only on certain time a year. The lower frequencies below 30 Mhz will reflect on the ionosphere all the time. At those frequencies weather has no effect because the wavelength are to long compared to water in the air.

Ducting happens 100% of the time over water. My job is to identify and extrapolate surface and elevated ducts. I'm sitting at my workstation now and I can tell how much of a duct exists in the atmosphere for any location on earth in real time.

The idea is about radio waves ducting. What frequencies are you referring to?

Quote from: rottingroom on April 17, 2014, 06:04:50 AM

Quote from: Starman on April 11, 2014, 06:36:25 AM

Quote from: 391MultiVac611 on April 09, 2014, 11:42:56 AM

Actually atmospheric conditions do play an important role in electromagnetic wave propagation.

Atmospheric inversion layers (most commonly temperature inversions) will refract electromagnetic waves of >= 90 MHz over the line of sight optical horizon due to the higher pressure of warmer air having a higher refractive index.

The result would seem as if the wave is traveling faster in lower density higher altitude air overtaking the wave portion in higher density lower altitude air, but in reality it is being refracted.

Radar and other technologies can take advantage of this phenomenon known as tropospheric ducting.

You are talking about ducting. It happens only on certain time a year. The lower frequencies below 30 Mhz will reflect on the ionosphere all the time. At those frequencies weather has no effect because the wavelength are to long compared to water in the air.

Ducting happens 100% of the time over water. My job is to identify and extrapolate surface and elevated ducts. I'm sitting at my workstation now and I can tell how much of a duct exists in the atmosphere for any location on earth in real time.

The idea is about radio waves ducting. What frequencies are you referring to?

All sorts. For every single naval radar in existence.

Quote from: Starman on April 17, 2014, 06:10:25 AM

Quote from: rottingroom on April 17, 2014, 06:04:50 AM

Quote from: Starman on April 11, 2014, 06:36:25 AM

Quote from: 391MultiVac611 on April 09, 2014, 11:42:56 AM

Actually atmospheric conditions do play an important role in electromagnetic wave propagation.

Atmospheric inversion layers (most commonly temperature inversions) will refract electromagnetic waves of >= 90 MHz over the line of sight optical horizon due to the higher pressure of warmer air having a higher refractive index.

The result would seem as if the wave is traveling faster in lower density higher altitude air overtaking the wave portion in higher density lower altitude air, but in reality it is being refracted.

Radar and other technologies can take advantage of this phenomenon known as tropospheric ducting.

You are talking about ducting. It happens only on certain time a year. The lower frequencies below 30 Mhz will reflect on the ionosphere all the time. At those frequencies weather has no effect because the wavelength are to long compared to water in the air.

Ducting happens 100% of the time over water. My job is to identify and extrapolate surface and elevated ducts. I'm sitting at my workstation now and I can tell how much of a duct exists in the atmosphere for any location on earth in real time.

The idea is about radio waves ducting. What frequencies are you referring to?

All sorts. For every single naval radar in existence.

It sounds interesting. How far will naval radar go in these conditions?

Quote from: rottingroom on April 17, 2014, 06:12:19 AM

Quote from: Starman on April 17, 2014, 06:10:25 AM

Quote from: rottingroom on April 17, 2014, 06:04:50 AM

Quote from: Starman on April 11, 2014, 06:36:25 AM

Quote from: 391MultiVac611 on April 09, 2014, 11:42:56 AM

Actually atmospheric conditions do play an important role in electromagnetic wave propagation.

Atmospheric inversion layers (most commonly temperature inversions) will refract electromagnetic waves of >= 90 MHz over the line of sight optical horizon due to the higher pressure of warmer air having a higher refractive index.

The result would seem as if the wave is traveling faster in lower density higher altitude air overtaking the wave portion in higher density lower altitude air, but in reality it is being refracted.

Radar and other technologies can take advantage of this phenomenon known as tropospheric ducting.

You are talking about ducting. It happens only on certain time a year. The lower frequencies below 30 Mhz will reflect on the ionosphere all the time. At those frequencies weather has no effect because the wavelength are to long compared to water in the air.

Ducting happens 100% of the time over water. My job is to identify and extrapolate surface and elevated ducts. I'm sitting at my workstation now and I can tell how much of a duct exists in the atmosphere for any location on earth in real time.

The idea is about radio waves ducting. What frequencies are you referring to?

All sorts. For every single naval radar in existence.

It sounds interesting. How far will naval radar go in these conditions?

I would need to know a location obviously. Unfortunately, I cannot divulge that information. I'm sure you understand. I can at least tell you that more often than not, ranges are actually greater when you are closer to the surface because surface ducting (which is available over water 100% of the time) can extend ranges as much as 100 times the normal capabilities of a radar.

I can understand most of it. Salt water acts like a giant sheet of metal.

I can understand most of it. Salt water acts like a giant sheet of metal.

Asking if you understand was not to infer that you don't understand ducting. I just can't give you details because it is secret.

Salt has nothing to do with it. It has everything to do with temperature inversion near the surface of water.

Quote from: Starman on April 17, 2014, 06:23:13 AM

I can understand most of it. Salt water acts like a giant sheet of metal.

Asking if you understand was not to infer that you don't understand ducting. I just can't give you details because it is secret.

Salt has nothing to do with it. It has everything to do with temperature inversion near the surface of water.

Sounds good. We will leave it at that.