Service difficulty report · Spar · Boeing 747230B

Difficulty date
September 21, 2004
Submitted
October 27, 2004
Operation
Air carrier
Aircraft
N512MC
Make and model
Boeing 747230B
Aircraft serial
21220
System (JASC)
5711 · Wing Spar
Part
Spar
Condition
Corroded
Location
Lt Wing
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

DURING SCHEDULED MAINTENANCE, CORROSION WAS FOUND LEFT WING SKIN FORWARD OF FRONT SPAR OLES 1378-1387, 1410, 1438-1447. CORROSION WAS REMOVED BY BLENDING. NDT INSPECTED TO CONFIRM DAMAGE FREE CONDITION. BLENDED AREAS WERE FLAP PEENED, ALODINE 1200 AND BMS 10-11 TYPE II PRIMER APPLIED. CUSTOM FILLERS WRE INSTALLED. TO RMOVED CORROSION AT OLES 1410, THE EXISTING CUTOUT IN THE SKIN LOCATED 4 INCHES OUTBOARD IS ENLARGED. SKIN FILLER IS SEGMENTED SO AS NOT TO BE LONGER THAN 8 INCHES. THREE REPAIR PLATES WRE MADE FROM .096 INCH THICK 2024-T3 ALUMINUM. (M)