What was found
DURING BASIC CHECK AT EAMS, A FASTENER HOLE ON THE RH HORIZONTAL STABILIZER UPPER SKIN, P/N 170-62726-016, AND ON THE UNDERLYING FRONT SPAR, P/N 170-62760-006, WAS ELONGATED (REF ETD2017-170-108564, FIGURES 1 AND 2). THE ELONGATED FASTENER HOLE IS LOCATED ON THE FRONT SPAR AND BETWEEN RIB12/RIB14. THIS EO IS BEING ISSUED TO PROVIDE INSTRUCTIONS TO ACCOMPLISH THE PERMANENT REPAIR OF THE ELONGATED FASTENER HOLE ON THE RH HORIZONTAL STABILIZER BY REAMING THE HOLE ON THE UPPER SKIN AND ON THE FRONT SPAR TO REMOVE THE DAMAGE AND INSTALLING 2EA BUSHINGS PER ETD2017-170-108564-A. BECAUSE THE RH HORIZONTAL STABILIZER UPPER SKIN AND THE FRONT SPAR ARE PRIMARY STRUCTURAL ELEMENTS (PSE), ACCOMPLISHMENT OF THIS EO HAS BEEN CLASSIFIED BY COMPASS ENGINEERING AS A MAJOR REPAIR DUE TO STRENGTH RESTORATION. EO E175-55MR-023.1 WILL BE ISSUED TO ACCOMPLISH FOLLOW UP INSPECTIONS: [REF TASK 55-10-001-0001 (EXTERNAL GVI THRESHOLD OF 20,000 FC, INTERVAL OF 20,000 FC) AND TASK 55-10-013-0001 (INTERNAL DET THRESHOLD OF 20,000 FC, INTERVAL OF 20,000 FC) ARE SUFFICIENT AND IS MET USING THE INSPECTION REQUIREMENTS: MPG/MRBR REVISION #13. THRESHOLD IS COUNTED SINCE NEW]. THE EO WILL BE ACCOMPLISHED ON WORK ORDER 2395516.