What was found
NR 1 & NR 2 ENG PYLON, STRUT AFT FAIRING HEAT SHIELD SPAR STRUCTURE, NR 5 FRAME P/N 313W3813-X HAS A 4.50 INCH CRACK ON THE LOWER AFT INBD CORNER. CRACK IS IN THE SAME LOCATION ON BOTH NR 1 & NR 2 ENG PYLON FRAMES. NR 2 ENG PYLON FRAMES NR 1 THRU NR 4, P/N'S 313W1813-X & 313W3813-X HAVE EVIDENCE OF HEAT DAMAGE AND SURFACE CORROSION. REF SRM 54-51-71 FIGURE 4. POSSIBLE CAUSE WAS AFT FAIRING HEAT SHIELD THERMAL BLANKETS NR 1 THRU NR 6 (NR 2 ENG PYLON) AND NR 6 (NR 1 ENG PYLON) WERE TORN AND WATER LOGGED. REF AMM 54-54-01 PG 426, 54-54-03 PG 406 AND 54-55-01 PG 623. AD 2002-07-07 AND SB 777-54A0017 ARE RELATED TO THIS BUT HAVE NOT BEEN ACCOMPLISHED. COMPLIANCE WITH AD WILL CORRECT CONDITION.