Originally Posted by H5487

Except for the landing and takeoff phases (and perhaps cropdusting and law enforcement ops) full-scale aircraft don't usually operate below 500ft above the highest obstacle in sparsely-occupied areas, 1000ft in congested areas. However, bear in mind that these altitudes were largely established back when accidental contact with an obstacle was the main concern. However, since 9/11, the Dept of Homeland Security has been diligently occupied with preventing a reoccurrence. This includes finding ways to identify potential threats in enough time to react to them. While a drone probably isn't a substantial threat to the airlines or crowds of people on the ground (not yet, anyway), I'm sure Homeland Security would prefer to keep larger (non-hobby) UAVs above 500ft where it is easier to spot and track them, as opposed to closer to the ground where they could be hidden by buildings, trees, etc. And since our models typically fly under 400ft, I can see where they would like to keep us confined to officially-recognized locations such as AMA Club fields.

Before someone posts that I'm predicting doom and gloom for our hobby, please note that I'm only speculating what some in the government would probably LIKE to do with us. The next terrorist attack on the US (and we'd be fools to say it can never happen again!) will determine just how much those DHS planners will get their way.

Harvey