If you find out it has a full range receiver and all your equipment is working correctly, the range will be further than you can see your plane.
Full range equipment is good for several kilometres.
When first starting with 2.4Ghz, I did my own full range tests -
See here (unfortunately since the RCU upgrade, the photos were lost on this old post)
And these vids.
http://www.youtube.com/watch?v=PPIWgfgvxAU
http://www.youtube.com/watch?v=KVIR0a9s8TE