ok i can only hover for like 2 min then it acts like the batt is dead. it flys great for the first 2 min then it falls to like 2ft off the ground and will stay like that for a while but it is strange when you push it to full the rpms drop.at first i thought it was the motor so i put a new one in that was not it so i put a differant battery in that was not it called e-flite they said it was the 3n1 so i put a new one in that was not it.i have played with pitch and that does not seem to make a diff. i have rebuilt the head three times new center hub ,spindle,main shaft,ect. any help whould be great
thanks

Tom