What was found
NR 4 LT FLAP TRACK BEAM ASSEMBLY FOUND WITH ADVANCED CORROSION IN HIDDEN AREA. THIS BEAM WOULD NORMALLY BE A REPEAT INSPECTION AND BLENDING OF WEAR POINTS. IT WAS DECIDED TO CHANGE OUT THIS BEAM TO HAVE IT OVERHAULED INSTEAD OF RE-WORKING ON WING. THE HIDDEN CORROSION WOULD NEVER BE SEEN UNLESS THE BEAM WAS REMOVED. THE CORROSION WAS ON ONE HALF OF ASSEMBLY P/N 85780011-007 AND SUBSEQUENTLY REPLACED THE ASSEMBLY P/N 85780011-005, S/N 019.