What was found
AIRCRAFT RETURN OF FLIGHT, RT ENGINE FIRE DETECTOR LIGHT TURNED ON AND IT TURNED OFF WHEN ENGINE WAS DECELERATED. DURING CHECK LOOPS WERE DETECTED GROUNDED, BOROSCOPIC INSP WAS PERFORMED TO RT ENGINE DETECTING 13TH STAGE BLEED DUCT DAMAGED. RT ENGINE MANIFOLD WAS REPLACED IAW MM AND A AND B LOOPS WERE ISOLATED AND TESTED IAW MM. AIRCRAFT WAS SENT TO MAIN BASE AND DURING OVERNIGHT DETAILED INSPECTION, IT WAS DETECTED NOISE SUPPRESSOR PANEL WITH DAMAGES. IN ORDER AVOID MORE DAMAGES TO SUCH ENGINE, IT WAS REPLACED IAW MM, TESTED CORRECT IAW MM.