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Help calculating search radius for downed mavic

Peter Babar

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Hey everyone,

I'd really appreciate your help. I'm going to help look for a crashed Mavic Pro in the next few days, and want to figure out what the ideal search area (perimeter) should be, taking into account (i) the possible margin of error by the Mavic when it recorded the final coordinates, and (ii) the margin of error of the GPS unit I'm going to be using to navigate to said coordinates.

I have two coordinates where I suspect the Mavic could be: the last one registered by the Mavic (coordinate A), and the one registered by the Mavic when "Find My Drone" was activated (coordinate B).

Coordinate A is: 46.312978, 13.887644
Coordinate B is: 46.312921, 13.887774

They're about 39 feet apart, according to Google maps. I don't know how accurate they were when they were measured, but I'm surprised that the last coordinates of the flight (after it crashed, and lay stationary), and the "Find My Drone" coordinates are so far apart.

Now, I'll be using a Garmin GPS unit to navigate to the search area, and it's only accurate to five decimal points.

I'd be really grateful for your advice on what coordinates I should use to define the search area. I assume it should be more or less oval- or rectangle-shaped. I will then search intensively for it, on the side of a mountain :/

Bonus points if you can actually help me figure out the four sets of coordinates for the rectangular search grid.

Many thanks!

Pete
 

mi8radire

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With such thick canopy i dont think tha your gps is going to be accurate at all
 
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sar104

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There's not really enough information there to give a useful answer. It would probably be more informative to consider the end of the flight track when the aircraft was above the trees with a good view of the GNSS constellations - assuming that it was flying above the trees. If both the coordinates that you mentioned are from the aircraft on the ground, and therefore from exactly the same location, then the difference between them potentially gives some idea of the spatial uncertainty but, with only two data points, not much confidence.
 

sleebus.jones

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I don't know if you've done much geocaching, but the GPS coordinates are usually just the start of the hunt unfortunately. Your phone may have better accuracy than your GPS unit. I use GPS Status on Android which would give you the accuracy you're looking for...I think. I can't get a fix in the office at the moment.
 

WAXMAN

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I don't know if you've done much geocaching, but the GPS coordinates are usually just the start of the hunt unfortunately. Your phone may have better accuracy than your GPS unit. I use GPS Status on Android which would give you the accuracy you're looking for...I think. I can't get a fix in the office at the moment.
Question? Is that the exact name of the app GPS STATUS? Thanks for any info.
 

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