lol, seems like a lot of people are having the same problem =/
unfortunately, you cant fly straight through some barriers.. in some areas though, if you fly inside the level you can find a spot where the barrier braks (way under the map, or way behind some kind of structure..)
its all about playin around and finding that perfect spot =/
hope you figure it out.. if you want we can hop in a game and work at it together (i havent been able to get out of all the maps using the debug =/)