THE AIRCRAFT STRUCK AND SEVERED 3 POWER LINES ABOUT 3 MILES SOUTH OF THE DEPARTURE AIRPORT. PRIOR TO THE ACCIDENT, IT WAS OBSERVED FLYING AT LOW ALTITUDE IN THE VICINITY. THE PILOT STATED THAT HE FLEW BY A MOBILE HOME PARK TO VERIFY THAT A TRAILER HAD BEEN MOVED. HE ALSO STATED THAT THE ENGINE WAS NOT DEVELOPING FULL POWER WHEN HE DEPARTED THE MOBILE HOME AREA AND THAT HE ENCOUNTERED TURBULENCE AND A DOWNDRAFT DURING CLIMB-OUT. HE THEN STRUCK THE LINES; HOWEVER, THE AIRCRAFT HAD SUFFICIENT POWER TO FLY THROUGH AND SEVERE THE 12KV LINES, WHICH WERE ABOUT 1/2 INCH IN DIAMETER, AND THEN CLIMB UP TO A SUFFICIENTLY HIGH ALTITUDE TO FLY BACK TO THE AIRPORT AND LAND. THE ENTIRE ENGINE COWLING WAS TORN LOOSE FROM THE EDGE OF THE FIREWALL ATTACH POINTS; THE PROPELLER TIPS WERE BENT FORWARD ABOUT 3 INCHES; 3 OF THE 4 LEFT WING STRUT ATTACH RIVETS AT THE WING ATTACH POINT WERE SHEARED; A NUMBER OF ELECTRIC ARC BURN SPOTS WERE FOUND ON THE PROPELLER AND LEFT WING SKIN.