How the charts are madeThe BackgroundFor the background the 'Interactive World Atlas', on CD is used. The area or part of it is displayed on the screen and is captured to an image file by using the graphics program 'Paintshop Pro' (version 6). In most cases, several captures are merged into one image file. The file's size should not exceed 1000 x 1500 pixels (roughly), to work conveniently. The ratio between width and height is kept between 1.3 and 1.5 to match paper formats when printed.Locations of beacons / airportsThe 'Airports and Facility Directory' of FS98 lists frequency, latitude and longitude of all radio beacons used by FS98. With the upgrades to FS2000, 2002 and 2004 my life has not become easier; there is no more listing and FS2004 does not even supply coordinates of beacons anymore. All beacons that will show on the chart, plus the neighbouring ones outside the chart area, are selected by screening the list (in the good old times) and nowadays by screening the map under the world...view map menu and extract the datas using pen and paper. The coordinates are input in a spreadsheet, each beacon one row.Bearing and Distance calculationA number of columns in the spreadsheet contain formulaes for calculating distance over a sphere, as well as bearings on a sphere. The formulaes were prepared for use in the spreadsheet by myself. One beacon is chosen as the base point. The datas of this beacon is copied to a special row in the top of the spreadsheet. Now the distance and bearing from each beacon in the list, referred to the basepoint, is calculated.Bearing correctionDue to unavoidable chart projection used by MS flightsimulator, the true bearing between 2 points can never be exactly the same bearing you use on the FS' compass (it's just because the world is round, even Microsoft cannot help it). Instead of applying the projection formulae MS has used (if even I would know them), I use an empirical way to determine the correction at a certain point: using the flightsimulator itself.Determining the bearing correctionSince FS2000, I use the GPS data results after making a flightplan from an airport near the point where I want to determine the bearing correction, to an airport far away (not less than 1000 miles). I compare the GPS heading of the direct flight with the calculated heading, using the same coordinates as FS does.In the pre-GPS era, with FS95 and FS98, things where more adventurous: I took a plane (the Cessna 182 is my favourite) and took the easiest way into the air possible: by clicking 'world', 'go to', 'exact location'. Then I keyed in a VOR beacon's correct longitude, the latitude minus 30 minutes of arc and an altitude of 25000 ft. I put the simulator in 'pause' mode, because I wanted to do the job frozen still in the air instead of tumbling to the earth in a vrille. The beacon's frequency was keyed in and the meter was adjusted in order to read the compass value. The deviation from North was the correction. Structure of the chartThe image file has 5 layers of map data. The first (bottom) layer is the topographic data and is kept in it's original status. The second layer is a vector layer, containing the lines. The third layer is a transparant layer where I make (white, yellow) colored areas. The fourth contains all the beacon texture and the fifth (top) layer contains all the text. In this structure, the chart is stored after completion, for future editing and upgrading. Before uploading the chart to the website, all layers are merged and it is saved as a GIF file.Placing beacons (on land)The atlas on CD program is running and it has a facility to show latitude and longitude of the cursor. The cursor is moved to the exact location and I make a good impression of it, in relation to the geographical features. Then I swap (under Windows) to the graphics program and get the same map in the screen, already captured before. I copy the beacon texture (circle or triangle) to the clipboard and paste it (transparant mode) to the 4th layer of the image file.Placing beacons (at sea)At lack of geographical features, the cursor is pointed to the exact location in the atlas program and the window is captured by use of the graphics program, including the cursor. In the graphics program, the captured area is reduced to show only the cursor and at least some geographical feature, such as an island of part of a coastline. This reduced area is now copied and pasted to a temporary 6th layer in the image file. It is moved so that the geographical features match. Then the beacon is pasted, in the 4th layer. The 6th layer is then made invisible and is eventually deleted after finishing the chart.Lines and textA line is drawn between two beacons and the corresponding nav-data is extracted from the spreadsheet. The bearing correction is applied, using the weighed average between the points where the correction was determined. The text is prepared and pasted along the line. If the line points to a beacon outside the chart area, the procedure is different: the pasted text is rotated according to the spreadsheet results, without bearing correction. Then the line is drawn, matching the direction of the text. Finally, the texted is moved to the line properly.Field testingA chart (of larger scale only) is not regarded as finished before a 'test flight', where all beacons are tested on existence and errors.
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