I understand that each RULE in RULES.TXT should contain:- Terrain type- Min Alt- Max Alt- Min Long- Max Long- Min Lat- Max LatHowever, some rules have an eighth entry, such as 0.4, at the end. I'm sure that this has been explained elsewhere but can't find the relevant post and can't remember the answer!Can anybody remind me what this mystery eighth entry is for?Many thanksJonathan Stonehouse

Hello Jonathan,Here in our Flight Unlimited library is a file named: outer_terrain_editor.zipBelow is an excerpt from the file"The airport clearing for Portland International Airport is right against a river, and we don

Many thanks.