Service difficulty report · Skin · Boeing 757251

Difficulty date
August 7, 2015
Submitted
August 13, 2015
Operation
Air carrier
Aircraft
N551NW
Make and model
Boeing 757251
Aircraft serial
26498
Aircraft time
41,570 hours, 18,372 cycles
Part
Skin
Condition
Damaged
Location
Bs 627
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

LIGHTNING STRIKE DAMAGE AT FS 627 BETWEEN STR S28L -29L. BLENDED AREA IAW SRM 53-00-01, FOUND TO BE OUT OF LIMITS; REMOVED DAMAGED AREA IAW SRM 53-00-01, REPAIR 14; C/W EDDY CURRENT INSPECTION AT CUTOUT IAW-SRM 53-00-01, REPAIR 14, STEP 3. NO ITEMS NOTED FABRICATED REPAIR PARTS IAW SRM 53-00-01, REPAIR 14. OK TO INSTALL REPAIR RII; INSTALLED DOUBLER IAW SRM 53-00-01, REPAIR 14; USING TABLE I, THE THICKNESS OF THE DOUBLER WAS DETERMINED TO BE .050"; USING TABLE II, PAGE 203, THE FOLLOWING INFORMATION WAS OBTAINED: WITH .040" SKIN, FASTENER BACR15FR4E-2 WILL BE USED IN THE NON-STRINGER HOLES AND BACR15FR6E-2 WILL BE USED IN THE STRINGER HOLES AND SPACING BETWEEN FASTENERS WILL BE .63" TO .75". TABLE II ALSO HAS 2 FOOTNOTES, WHICH SAYS THIS REPAIR IS NOT NEAR STATIC PORTS NOR AA SENSORS AND C WHICH REFERS TO REPAIR GENERAL FOR REPAIR ZONES. TABLE IV WAS ALSO USED. IT SAID THE VISUAL INSPECTION WILL OCCUR EVERY 1,000 FLIGHT CYCLES AND THE TIME LIMITED REPAIR WILL BE REPACED BEFORE 3,000 FLIGHT CYCLES.