As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING COMPLIANCE WITH PIPER SB 974, DYE PENETRANT INSPECTION OF THE INBOARD HINGE AREA OF THE LEFT AILERON SPAR INDICATED A CRACK. INSPECTION WAS REPEATED WITH SAME RESULT. NOTE: THIS CRACK WAS NOT VISIBLE DURING VISUAL INSPECITON. SPAR WAS REPLACED AND SERVICE BULLETIN COMPLETED.