What was found
DAMAGE WAS FOUND TO THE 142U0086-198 STRINGER 31L AT BS 550 AFTER A BURST EQUIPMENT COOLING EXHAUST VALVE TRUCK THE S-31L STRINGER AND SKIN. REFER TO EO 4453A362 FOR THE SKIN REPAIR. THE 142U0086-198 STRINGER IS MADE FROM 0.050 INCH THICK 7075-0 SHEET PER QQ-A-250/12 HEAT TREATED TO T62 AFTER FORMING. IN THE AREA OF THE DAMAGE, STRINGER HAS A MACHINE TAPER 0.050 TO 0.040 INCH OVER 197 INCHES. PART 1 OF THIS EO ACCOMPLISHES THE TIME LIMITED REPAIR OF THE STRINGER. THE REPAIR IAW PART 1 OF THIS EO IS CATEGORY C AND REQUIRES REPETITIVE INSP IAW PART 2 OF THIS EO AT A-CHECK INTERVALS AND REPLACEMENT AT THE NEXT C-CHECK AFTER 24MAY2010 IAW PART 3 OF THIS EO. PART 2 OF THIS EO REPETITIVELY INSPECTS THE PART 1 REPAIR TO ENSURE CONTINUED AIRWORTHINESS. PART 3 OF THIS EO ACCOMPLISHES THE INTERIM REPAIR AT THE NEXT C-CHECK AFTER 24MAY2010 IAW SRM 53-00-03, FIGURE 201, REPAIR 3.