SDR DALA2018100505919

Service difficulty report · Door Sill · Boeing 757251

Difficulty date: October 4, 2018
Submitted: October 8, 2018
Operation: Air carrier
Aircraft: N551NW
Make and model: Boeing 757251
Aircraft serial: 26498
Aircraft time: 51,344 hours, 22,152 cycles
System (JASC): 5320 · Fuselage Miscellaneous Structure
Part: Door Sill
Condition: Corroded
Location: Fuselage
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

CORROSION ON CARGO DOOR LOWER SILL FROM STA BS1380 TO BS1440, AT AFT CARGO COMPARTMENT. DOOR LOWER SILL (FLOOR SUPPORT) WAS FABRICATED AND REPLACED PER DWG 146N5391 REV F AND SRM 51-30-01, 51-40-05, 51-40-08, 51-40-02 PAR 4. (UT) WAS ACCOMPLISHED PER NDT MANUAL PART 4. 51-00-10 THE ORIGINAL THICKNESS ON DOOR LOWER SILL IS .063" REMAINING THICKNESS IS .035" THEREFORE IT’S OUT OF LIMITS PER SRM 53-60-15 AD 2.