FRIENDS AND FAMILY OF THE 69-YEAR-OLD PILOT WERE VISITING AT HIS COTTAGE OVER THE FOURTH OF JULY HOLIDAY. THE PILOT'S STATED INTENTION WAS TO FLY HIS AIRPLANE TO PICK UP HIS GIRLFRIEND. THE FRIENDS REPORTED THEY OBSERVED THE AIRPLANE FLY 'LOW OVER THE BACK YARD IT STARTED GOING UP...AGAIN AFTER HE GOT OUT OF SIGHT...WE ALL HEARD LOUD BANGING, CRACKLING NOISES...' THE FRIENDS/RELATIVES REPORTED THE PILOT HAD MADE LOW PASSES OVER THE COTTAGE ON PREVIOUS OCCASIONS, BUT HE SEEMED LOWER THAN USUAL ON THIS PASS. THEY STATED: 'WE THOUGHT HE WAS PLAYING A JOKE ON US POSSIBLY WITH FIRE CRACKERS...' DAMAGE TO TREES AND WRECKAGE DEBRIS REVEALED THE AIRPLANES RIGHT WING IMPACTED A TREE ABOUT 75 FEET ABOVE THE GROUND. THE OUTBOARD SECTION OF THE RIGHT WING SEPARATED AND THE AIRPLANE DESCENDED THROUGH THE TREES, COMING TO REST INVERTED. POST-ACCIDENT INVESTIGATION REVEALED NO EVIDENCE OF PRE-IMPACT MECHANICAL MALFUNCTION.