Capitulo 55 Estabilizador Villafaña Martínez Arturo BAC1514-1681 7075-T6511 extrusion BAC1503-100235 2024-T3511 extrusion 7050-T7451 plate REPAIR 4 - HORIZONTAL STABILIZER MACHINED INSPAR RIB STIFFENER CRACK RE Repair Instructions • A. Get access to the damaged area. You may need to install an access panel in the lower inspar skin to get access. Refer to 55-1001, REPAIR 7 or 55-10-01, REPAIR 8. • B. Remove the damaged part of the rib as shown in Figure 202/REPAIR 4. Refer to 51-10-02, • GENERAL. (1) Cut and remove the damage from the vertical stiffener of the rib. (2) If the crack extends into the web of the rib, cut and remove the damage from the web. Make the corner radii of the web cutout a minimum of 0.167 in. (4.24 mm). NOTE: Increase the corner radius where you can keep the 1.5D fastener edge margin between the cutout and all the repair parts, except as noted on Figure 202/REPAIR 4. NOTE: Adjacent Rib bays at vertical stiffener location may vary in web thickness. In this case, trim the stiffener flush to the thicker web thickness. • C. Do a HFEC inspection of the cut edges of the stiffener and web as applicable for cracks as shown in 737 NDT Part 6, 51-00-00, Procedure 4 or 737 NDT Part 6, 51-00-00, Procedure 23 . • D. Do a HFEC inspection of all existing fastener holes within the repair area for cracks as shown in 737 NDT Part 6, 51-00-00, Procedure 16. • E. Do a general visual inspection of all areas within the repair area (including underlying structure) for corrosion, existing repairs or any other defects. If discrepancies are found, contact the Boeing Company. • F. Make the repair parts. Refer to Table 201/REPAIR 4 for the repair material. (1) For cutout length less than 2.01 inches (50.9 mm), refer to Figure 202/REPAIR 4, Detail A. (2) For cutout length 2.01-3.00 inches (50.9-76.2 mm), refer to Figure 202/REPAIR 4, Detail B. • REPAIR 5 - HORIZONTAL STABILIZER MACHINED INSPAR RIB LOWER CHORD AND VERTICAL STIFFENER CRACK REPAIR Repair Instructions • A. Get access to the damaged area. You may need to install an access panel in the lower inspar skin to get access. Refer to 55-1001, REPAIR 7 or 55-10-01, REPAIR 8. • B. Remove the damaged part of the rib as shown in Figure 202/REPAIR 5, Figure 203/REPAIR 5, or Figure 204/REPAIR 5. Refer to 5110-02, GENERAL. (1) Cut and remove the damage from the lower chord of the rib. Removal of chord radius is allowed, but do not cut into rib web. (2) For repair as shown in Figure 203/REPAIR 5, Detail A or Detail B cutout the rib vertical stiffener as needed. (3) For repair as shown in Figure 204/REPAIR 5, Detail A or Detail B remove the damage from the rib vertical stiffener. (a) If the crack extends into the web of the rib, cut and remove the damage from the web. Make the corner radii of the web cutout a minimum of 0.167 in. (4.24 mm) NOTE: Increase the corner radius where you can keep the 2D fastener edge margin between the cutout and all the repair parts. Refer to Figure 204/REPAIR 5, Details A and B. NOTE: Adjacent Rib bays at vertical stiffener location may vary in web thickness. In this case, cutout the stiffener to the thicker rib web thickness. • C. For repair as shown in Figure 205/REPAIR 5, Detail A or Detail B, remove damage from horizontal rib chord. (1) Cut and remove the damage from the lower chord of the rib. Removal of chord radius is allowed, but do not cut into rib web. • D. Do a HFEC inspection of the cut edges of the chord, stiffener and web (if applicable) cutouts for cracks as shown in 737 NDT Part 6, 51-00-00, Procedure 4 or 737 NDT Part 6, 51-00-00, Procedure 23
