the servos are new purchased a while back and yes setting up the plane i used a sub-c 4.8 volt pack to find center for control linkage then switch to the regulated ions for control throws, rates and mixes ,just a guess but the servos were powered up for 30 to 45 minutes and to be fare there is no run in the f-18 wing for them to breath maybe they just got to hot running in full rates for that long ,hitec did sudjest that could be the case