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The free software FAA software compsys21 will do this and more
That's interesting but for something the size of half-a-state I would more likely work with UTM coordinates and then use plane survey formulas... Why use an inaccurate approximation when better software already exits??? You give yourself away with a comment like that... Projections to rectangular grids are not intended to be approximations but are intended to be rectangular grids. Latitudes and longitudes labeled on an atlas are first converted to rectangular coordinates, plotted as rectangular coordinates, and then labeled as latitude and longitude. In other words any point (within range) has both latitude / longitude location and UTM grid location. Simply there is a conversion between the two. Okay, UTM and geodetic have different directional orientations. But in project layout any point is relative to two or more other points. In project layout there is no such thing as one point relative to only one other point because that would be a magical creation. The point is that UTM directional orientation is used with UTM points and that geodetic directional orientation is used with geodetic points. (For example, the consumer GPS user can do this by getting their GPS location, getting a GPS location of a skyscraper or transmission tower that can be seen in the distance, and then laying out an angle to a required point using their home point location and the line of sight to the tower. Note the three points and that is project layout.) Also, a bearing in UTM is one direction to the point. And that is likely what is required on a project. A geodetic bearing is simply a beginning direction to the point and directional corrections are required. That may be okay for navigation but would very strange in project layout...So a layout in UTM is a rumb line while a geodetic layout is a great circle. Note that a point laid out on a rumb line in a UTM grid could after layout be converted to latitude and longitude. In other words simply meet requirements and output in any required format. Of course for higher accuracy, projections to state plane coordinates are used instead of UTM coordinates. And state plane coordinates are used extensively in project layout. There are not a bunch of engineers walking around saying "...why use an inaccurate approximation..." as the project is simply defined with a rectangular coordinate system. Finally, one benefit is using rectangular coordinates are that simple formulas can be used with rectangular coordinates. Someone with an inexpensive scientific calculator can make on-site calculations that for instance a construction crew might be waiting on. And of course a $90 HP48 will hold and quickly run all of the plane survey formulas and will fit in shirt pocket. Furthermore, plane survey formulas can be developed for PC programs in short periods of time and without access to highly developed formal sources of information or expertise. So if the project is defined with rectangular coordinates why have a software that does not apply to the task ? |
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