How about all of the above, and additionally expense! Some people really don't care what they spend on their plane, I do! The engineer in me also begs me to ask if the alteration of hydrocarbon to another chemical in the atmosphere is really helpful AT ALL. Most "environmentalists" are ignorant idiots and the sooner we start listening to real scientists as opposed to paid "advocates" I'll feel a lot better about it. Anthropomorphic global warming is BS, get over it. Sorry for the rant.
-- 
Homepage: http://www.flyrotary.com/ 
Archive and UnSub: http://mail.lancaironline.net:81/lists/flyrotary/List.html