Basicly if you are under abour 2ft altitude helis get bad turbulance, it usually results in the heli hugging the ground and sliding off everywhere like a hovercraft (i think americans call them air boats) so to get the heli to fly easyly you have to fly it above about 2ft

which is a problem - its scary to fly that high when you arnt experienced, but it does get much easyer when your out of it so helis might not be as hard as you think after your first few flights