i have one of these attached to my phantom
http://www.amazon.com/DS-30-1-Cente...8&qid=1437512832&sr=8-1&keywords=drone+strobe
I have it screwed into the bottom of the gimbal guard and wired to an aux 12v output i have coming out of the body. The battery drain is negligible and it is really bright and strobes slightly quicker than once per second. Helps with finding it if you lose line of sight momentarily.
In general, whenever i'm outside i play spot the aircraft. As soon as i hear an engine, i try to pinpoint where the aircraft is and have gotten pretty good with some practice. I can now spot most within 15 seconds. I too fly in areas that on occasion have low flybys from helicopters. I wish there was a better way to coexist but nothing much better yet.