I'm out in Naperville, so I have pretty easy access to open farm fields and some of the Forest (Prarie) Preserves are fairly isolated and devoid of people. DuPage county, at least, has several model aircraft sites in Forest Preserves, but only one is for Helis - the model aircraft parks with runways tend to not like Helis getting in the way. Check out the AMA web site and check google for park district property in your area. I doubt there's any room at Cook County green spaces if that's where you live, but, man, I'd love a reason to get a waiver to video Chicago at night from 1000'. ;-)
- Mike