Service difficulty report · Floorbeam · Boeing 7378H4

Difficulty date
March 27, 2023
Submitted
April 27, 2023
Operation
Air carrier
Aircraft
N8529Z
Make and model
Boeing 7378H4
Aircraft serial
36974
Aircraft time
19,992 hours, 9,666 cycles
Part
Floorbeam
Condition
Corroded
Location
Zn 200 Fus Top
Stage of operation
IN
How discovered
9
Nature of condition
O
Precautionary procedure
K

As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.

What was found

CORROSION ON 328 FLOORBEAM UPPER FWD FLANGE AT RBL 21; RBL 40; RBL 48; WL 208.<REMOVED CORROSIONS BY 2.0'X1.5'X.025' ON FLOOR BEAM BS 328; RBL21; RBL40; RBL48; WL208 FOUND TO BE OUT OF LIMITS BECAUSE EXCEEDED 15% ORIGINAL MATERIAL THICKNESS WAS .125' IS NOW .100' IAW SRM 53-10-51-1A-1.REMOVED DAMAGED FLOORBEAM UPPER FLANGE SECTION AT BS 328 RBL 1.10 TO RBL 64 PER SRM 53-10-51-2R-7 REPAIR 7 MODIFIED INTERCOSTAL BS 328 TO 344 RBL 24 PER SRM 53-10-51-2R-7 REPAIR 7 STEP 4 PAR F. APPLIED CHEMICAL CONVERSION COATING AND PRIMER PER 53-10-51-2R-7 REPAIR 7 FABRICATED REPAIR PARTS: ITEM [1] T-CHORD EXTRUSION BAC1505-100224#7075T6511 LOT#1521819-1; ITEM [2] ANGLE (2 EA.) BAC1490-2811#7075T62 CLAD LOT#1491932-1; ITEM [3] ANGLE (2 EA.) BAC1490-2900#7075-T62 CLAD LOT#1519553-1; LOCATED HOLES; DRILLED; DEBURRED; AND APPLIED CHEMICAL CONVERSION COATING AND PRIMER PER SRM 53-10-51-2R-7 REPAIR 7 INSTALLED 100% TEMP. AND PERMANENT FASTENER WITHIN SEALANT SQUEEZE-OUT TIME BMS-5-95 TYP 1 C20 USED; APPLIED AT 05-APR-2023 15:30 UTC PER SOPM 20-50-19 AND SRM 53-10-51-2R-7INSTALLED REPAIR PARTS ITEM 1 T-CHORD(1EA); ITEM 2 ANGLES (2EA); ITEM 3 ANGLE (2EA) ITEM 4 SHIMS (9EA); ITEM 5 ANGLE (1EA); ITEM 6 FILLER (1EA) AND INSTALLED ALL PARTS REMOVED FOR ACCESS ON BS 328 RBL 1.10 TO RBL 64 PER SRM 53-10-51-2R-7 REPAIR 7; SRM 51-40-02-0G-0; DWG 274A9410; AND DWG 141A5400;[ APPLIED FILLET SEAL AROUND; FILL ALL INTERNAL GAPS AND APPLIED CIC ON REPAI

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