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Old 19th April 2020 | 09:17
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buzzc152
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Converting 2 angular measurements to distance on the earth.

If 2 aircraft at roughly the same latitude measure the sun in the sky at 2 different angle, how can you use that to estimate distance between the 2 aircraft ?
To my puny brain I can just take the number of arc minutes difference and call that nautical miles between them. Does that work ?

eg, Aircraft A measures the sun to be 10º above the horizon and aircraft B measures it as 5º. So, 5º difference between them equals 5ºx60" = 300nm separating the two. If so, why does that work ?

Does that work at all latitudes or would I have to make a correction (struggling to remember my atpl theory stuff 20 years ago). Also, what is the effect if the aircraft are at very different altitudes ?

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