Difference between revisions of "Talk:Air geohash achievement"
imported>Danatar (how near do I have to be for an air geohash?) |
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==Distance allowed for valid expedition== | ==Distance allowed for valid expedition== | ||
| − | I just tried to figure out how near I have to be to the hashpoint while flying, using the 10 arc second rule. While doing that, I read Robyn's calculations on [[2008-10-16 59 -122]] and I think there is an error/misinterpretation. To get the 300 metre radius, | + | I just tried to figure out how near I have to be to the hashpoint while flying, using the 10 arc second rule. While doing that, I read Robyn's calculations on [[2008-10-16 59 -122]] and I think there is an error/misinterpretation by whoever first said "10 arc seconds". To get the 300 metre radius, Robyn took 10 arc seconds of the world's radius/circumference (6370 km and 40000 km resp.); But this means the "coordinates reached" radius neglects altitude above sea/ground level: It is 309m while flying at an altitude of 1 metre above sea level and only half a metre more while flying in a passenger plane at an altitude of 10km. I don't think that's what has been intended while creating the achievement. On the other hand, when starting counting from ground level, 10 arc seconds are about 0.5 centimetres for every 1 kilometre altitude, and that's not possible to achieve. I think we should change the requirement to "percentage of altitude", but how large should this percentage be? For a remotely controlled device, 1 metre at an altitude of 10 metres above ground should be possible with a few tries, this would be 10% and give 1 kilometre for a passenger plane flying at 10 kilometres. Or a larger percentage (20%) up to a certain altitude (1km / 1 mile...), and less above that. Please give your opinion. - [[User:Danatar|Danatar]] 11:31, 9 November 2008 (UTC) |
Revision as of 11:31, 9 November 2008
Removed the kite section, due to the availability of the Geohash By Proxy achievement. --Pardey 07:04, 20 October 2008 (UTC)
Distance allowed for valid expedition
I just tried to figure out how near I have to be to the hashpoint while flying, using the 10 arc second rule. While doing that, I read Robyn's calculations on 2008-10-16 59 -122 and I think there is an error/misinterpretation by whoever first said "10 arc seconds". To get the 300 metre radius, Robyn took 10 arc seconds of the world's radius/circumference (6370 km and 40000 km resp.); But this means the "coordinates reached" radius neglects altitude above sea/ground level: It is 309m while flying at an altitude of 1 metre above sea level and only half a metre more while flying in a passenger plane at an altitude of 10km. I don't think that's what has been intended while creating the achievement. On the other hand, when starting counting from ground level, 10 arc seconds are about 0.5 centimetres for every 1 kilometre altitude, and that's not possible to achieve. I think we should change the requirement to "percentage of altitude", but how large should this percentage be? For a remotely controlled device, 1 metre at an altitude of 10 metres above ground should be possible with a few tries, this would be 10% and give 1 kilometre for a passenger plane flying at 10 kilometres. Or a larger percentage (20%) up to a certain altitude (1km / 1 mile...), and less above that. Please give your opinion. - Danatar 11:31, 9 November 2008 (UTC)
