What was found
DURING HEAVY MAINTENANCE AREA INSIDE THE LH HORIZONTAL STAB HAS (1) SPOT OF POSSIBLE CORROSION ON THE SPAR WEB LOWER MID SECTION @ APPROXIMATELY (XE-217.500) JUST BELOW THE FASTENER ROWS. AFTER FURTHER EVALUATION OF AREA AT INSIDE THE LH HORIZONTAL STABILIZER SPAR WEB LOWER MID-SECTION AT APPROX. XE 217.500, JUST BELOW FASTENER ROW, FOUND NO EVIDENCE OF CORROSION AT THIS TIME IAW MD-11 SRM 51-21-01. THE AIRCRAFT WAS APPROVED FOR RETURN TO SERVICE.