exncsurfer
Pattern Altitude
I did, so I emailed them and got the answer.
My example, notice the two checkpoint flags and two airport info text blocks for SUT:
And the explanation:
"This is an interesting situation due to the way VFR charts are produced. I am going to attempt to write out the process so bear with me… The current process of maintaining and producing VFR charts focuses primarily on supporting the printing of a folded paper chart from which these production files are used to create the digital VFR charts. Each folded paper VFR Sectional is printed on a large sheet of paper that is printed on both sides so that each half has a north and a south side of the chart. By cutting each sheet of paper in half two folded VFR charts are created out of one sheet of paper. Similar to how every sectional has an overlap to an adjoining chart to the north, east, south, and west, each individual sectional also has an overlap when flipping the paper chart over from south/north. In order to allow for the user to easily identify where they are when moving from one side of the chart to the other, a slight overlap is created. Sometimes aeronautical information falls in this overlapping area and shows up on both the north and south half of the paper chart. In order to provide the information on both halves, we duplicate the information so that it appears on each side. Now to explain why this is showing up on the digital versions…this is because we use the same files for printing as we do when creating pdf or geotiff formats. So if you look closely to other sectionals you will notice similar duplication of information in the approximate halfway point of sectionals.
We are currently working on an alternative production system from which one of the many benefits would be the elimination of overlapping information by creating a seamless national VFR chart"
My example, notice the two checkpoint flags and two airport info text blocks for SUT:
And the explanation:
"This is an interesting situation due to the way VFR charts are produced. I am going to attempt to write out the process so bear with me… The current process of maintaining and producing VFR charts focuses primarily on supporting the printing of a folded paper chart from which these production files are used to create the digital VFR charts. Each folded paper VFR Sectional is printed on a large sheet of paper that is printed on both sides so that each half has a north and a south side of the chart. By cutting each sheet of paper in half two folded VFR charts are created out of one sheet of paper. Similar to how every sectional has an overlap to an adjoining chart to the north, east, south, and west, each individual sectional also has an overlap when flipping the paper chart over from south/north. In order to allow for the user to easily identify where they are when moving from one side of the chart to the other, a slight overlap is created. Sometimes aeronautical information falls in this overlapping area and shows up on both the north and south half of the paper chart. In order to provide the information on both halves, we duplicate the information so that it appears on each side. Now to explain why this is showing up on the digital versions…this is because we use the same files for printing as we do when creating pdf or geotiff formats. So if you look closely to other sectionals you will notice similar duplication of information in the approximate halfway point of sectionals.
We are currently working on an alternative production system from which one of the many benefits would be the elimination of overlapping information by creating a seamless national VFR chart"
