Hey Dugout, I think you give them to much credit and it sounds like you would have no problem by detection from the air as far as the plant itself goes. There is no gear on board which would say detect and zoom in on plant material. They look for human habits as a general rule as stated above, garden layouts, tender camp sites, parked vehicles etc. If they do have FLIR gear, it will clearly show you hiding under a tree whether dressed in camo or not. As the 98.6* hotspot, you look like a white cow in a coal dust storm and they would be curious. I have a patch at the back of my grand dads acreage and I just wear my jeans with a dark shirt. I also always have a fence plier, my leather gloves and a 6" spool of bailing wire so if neighbor spots me while working his land, I just grab some sagging fence line and act like I'm patching while giving him a wave. We do also have a lot of copters flying about being about 50 miles from a Navel Air Station and large AFB about 70 miles away. The best way to identify these birds you mentioned you have seen around your place, is to jot down the tail numbers Nxxxyy if possible then check registry at:
Aircraft Registration Inquiry
If it says Dept. of Justice or similar, you got problems. For example in Dallas, if you ever see N999zy, its the Fed. You will also notice a camera ball on the nose as well as an IR spot on the rear of the fuselage on this bird.
It sounds like your risk would be more likely to come from someone sending them right to it. You mentioned deer trails which raises the question of not only wildlife, but possibly the owner leasing to hunters and such. Try to scout the area to include looking up trees for deer hunting blinds and such. The other source you have control of entirely, that is tell NO ONE of your grow. Not loved ones, high school buddies or best friends period. Every time you might be tempted, think about it for 1 second, then don't do it. Scorned lovers, brother-in-laws you didn't loan money to, and many many more have come to past. Just wait until you have the cured bud in glass as at that point you are taking the same risk as most of us just possessing.