What was found
ON FINAL APPROACH, CONFIGURED AT FLAPS 15, SLAT EXT. WHEN ATTEMPTED TO EXTEND FLAPS TO 28, RECEIVED FLAP DISAG ALERT . RECYCLED FLAPS, SAME RESULT RAN QRH FOR FLAP DISAG, LANDED WITH FLAP 15, SLAT EXT CONFIGURATION. INSPECTION FOUND LT I/B FLAP FOLLOW UP CABLE & CABLE PULLY DAMAGED. REMOVED DAMAGED LT FLAP BUSS CABLES IAW MM 27-51-11-4. RIGGED FLAP BUSS CABLES IAW MM 27-50-00-5. REPLACED ONE PULLEY IAW DWG NEH6003. COMPLETED RIG OF FLAP BUSS CABLES. COMPLETED SAFETIES ON ALL TURNBARRELS IAW MM 27-50-00-5 AND ALL OPS CHECKS GOOD.