I also have the aerohawk. Mine came with 2 sets of batteries, I don't know why but with one set the heli flys beautifully (I can't control it very well, but it goes skward with only 1/2 throttle). The second battery will not let the heli leave the ground. They both check out on a voltmeter as having 8.4volts, but one does not work in the heli (the heli gets very light and will occasionally go 2 inches in the air before coming down again).
Of course I tried to start with the bad battery (didn't know it was bad at the time) and when it wouldn't leave the floor, I twisted the main blades (as it says in the manual) eventually the battery was flat and the heli still hadn't lost contact with the floor. Then I tried the second battery set and it wouldn't fly (I was seriously pissed off) but I decided to bend the baldes back to try and get to the original configuration. Well the heli flew, I then bent them back even further and the heli flew even better! With the good battery I can get around 15 minutes of uncontrolled flight and its real fun. But I seem to be making very slow progress in learning to control this helicopter, I don't know if I am a slow learner or if this is just a very difficult heli to learn on. I have got it nicely adjusted so that it takes of from the ground with almost no rotation about the main axis (the gyro works nicely), but the cyclic controls really seem to do very little to the flight direction!! Still its fun and has proved not to be very expensive so far.. A good upgrade is to get a peak detect quick charge, I can fly for 15 minutes and in 10 minutes have the battery recharged for another flight.. Now I just need to replace the defective second battery. I have no idea when I will be good enough to actually fly it indoors, at the moment it has a mind of its own regarding where it wants to go!

Hope this might help.

Gary