What was found
AIRCRAFT RETURNED TO FIELD AFTER ENGINE HAD A COMPRESSOR STALL JUST AFTER TAKEOFF. DISASSEMBLY OF THE ENGINE SHOWED TEARS AND MISSING MATERIAL ON COMPRESSOR BLADES AND VANES STAGES 6 THROUGH 9 DUE TO A STAGE 8 VANE SECTOR HONEYCOMB FAILURE. FAILURE OF THE HONEYCOMB IS A RESULT OF SEAL SLOT CRACKING WHICH EVENTUALLY ALLOWS THE HONEYCOMB TO SEPARATE FROM THE VANE SECTOR. THE HONEYCOMB IS INSTALLED WITH A TIGHT SNUG FIT TO THE SEAL SLOTS. BECAUSE OF THE THIN SLOT WALLS AND SNUG HONEYCOMB FIT A CAUTION WAS ADDED IN THE JOB INSTRUCTION CARD (JIC) WHEN INSTALLING VANES SECTOR SEALS TO ENSURE STRESS RISERS ARE NOT INTRODUCED TO THE SEALS SLOTS DURING HONEYCOMB INSTALLATION.