Service difficulty report · Sill Drain · Boeing 7377H4

Difficulty date
August 6, 2026
Submitted
September 11, 2026
Operation
Air carrier
Aircraft
N931WN
Make and model
Boeing 7377H4
Aircraft serial
36637
Aircraft time
56,214 hours, 34,452 cycles
Part
Sill Drain
Condition
Corroded
Location
Zone 200
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 FOUND ON TOP & UNDERSIDE AFT (WET AREA) FLOOR STRUCTURE AT RBL 57 BS 947 - BS 990 (MOP-SILL) CORROSION ON ASD INNER CHORD EVALUATED AND FOUND TO BE OUT LIMITS IN AN AREA OF 4.1"LX1.5"WX0.02"D REMOVED AND REPLACED I.A.W SRM 51-40-02-0G-0 AND BOEING DWG 147A8501 REV: B 147A8501 REV: B 147A8540 REV: B VERIFIED ACTION 1 MEASUREMENT TABLE UPDATED VERIFIED CORRECTIVE ACTION ITEM #3.

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