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sinemora

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quote:
Originally posted by -SineMora-:

If I have a known point, then have a direction in degrees minus declination and a distance, how do I find the grid or new coord's? I think there is a formula but I can't recall it.


 

The answer depends on a lot of things. Do you want an accurate result, or are you willing to approximate the Earth as a sphere? For magnetic headings of relatively short distances (less than 1 km or so) then the spherical approximation is probably OK, and there is a formula, which you can find at the Aviation Formulary.

 

For accurate calculations using the ellipsoidal model of the Earth, there is no closed-form equation. The calculations are done iteratively. You can try my program GeoCalc, which does those calculations.

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Since the probability that you do have access to a GPS unit is high, considering that you are writing in this forum, you have an excellent tool there.

The GPS can be used as a calculation device too, for solving problems like this.

Enter the coordinates of the known point as a waypoint. Then project a new waypoint in the desired direction, at the distance in question, and it will calculate the new position for you.

 

Anders

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quote:
Enter the coordinates of the known point as a waypoint. Then project a new waypoint in the desired direction, at the distance in question, and it will calculate the new position for you.


 

I don't know 'bout other GPSr's,

but

the SporTrack does that: go to the position screen,

then menu

next choose "projection"

fill in the distance and degrees (angle)

and the answer comes as a projected waypoint.

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