Originally Posted by stevebarrow
As you go into the loop and over the top you need to change pitch. If you keep positive pitch at the top your heli is pushing itself down. Enter the loop and as you go up and over gently pull on a little negative pitch and as you come down and back to upright change to positive again.
+1. You also want the heli to be travelling reasonably fast forward before you enter the loop. If it's going fast enough you won't even need negative pitch; 0 degrees pitch as the heli goes over the top when it's upside down is enough, as centrifugal force will prevent it from losing altitude.
Another tip is, pull back on the cyclic just a bit to enter the loop, leave the cyclic stick in the same position until the heli has completed the loop, and just concentrate on working the collective.