What was found
DURING A 100-HOUR INSPECTION, THE MECHANIC DISCOVERED A SIGNIFICANT CRACK/BREAK OF THE AIRCRAFT'S HORIZONTAL STABILIZER 'BRACKET ASSEMBLY,' P/N 0432004-9, THAT SEVERELY COMPROMISES THE INTEGRITY OF THE AIRCRAFT VERTICAL FIN MOUNT. THE NUTPLATES WITHIN THE SUBJECT PART ARE SUBJECT TO AD 80-11-04.