Arrakis, the other forum broke their necks by google earth google line google landscape versions, (and checking how google works by distance btw 2 mountain peaks), by entering Near and Far Beacons' co-ordinates (in degrees, geographically, in the word overall), and it seems by all systems possible. Sometimes they get 6100 sometimes 6300. And say it's all turned 170 degrees sideways somewhere. Either way majotity votes for 6300. Amelin wrote "question open, suspended" :o)