Service difficulty report · Skin · Boeing 747409

Difficulty date
June 1, 2011
Submitted
June 2, 2011
Operation
Air carrier
Aircraft
N168CL
Make and model
Boeing 747409
Aircraft serial
29906
Aircraft time
55,947 hours, 9,810 cycles
Part
Skin
Condition
Cracked
Location
Bs 1728
Stage of operation
IN
How discovered
V
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 TRANSIT CHECK, FOUND A POP-UP SKIN WITH A 0.5 INCH LENGTH CRACK LOCATED ON S44R, BS 1728. CHECKED INTERIOR SKIN AND DISCOVERED CORROSION COMMON TO INTERIOR BELLY SKIN ALONG S44R EDGE. DETAILED VISUAL INSP ON ADAJCENT STRUTURE FOUND OTHER 2 SKIN CRACKS AND CORROSION LOCATED AT APPROX. BS 1728, S43R AND S45R. SKIN UNDERSURFACE CORROSION MIGHT HAVE CAUSED THE SUBJECT CRACKING. HAVE REPORTED THIS PROBLEM TO MFG AND REQUESTED FOR ADVANCE MX PLAN. THE SUBJECT DAMAGE CAN BE REPAIRED IAW SRM 53-00-01 REPAIR 1. SPECIAL INSPECTION EO WILL BE ISSUED FOR THE FLEET TO PERFORM ONE TIME INSPECTION WITHIN 2 WEEKS, AND REPEAT INSPECTION AT R CHECK.