EASA AD US-2019-03-24: Fuselage - Overwing Emergency Exit Doors - Inspection

What to do

Operators of affected Boeing 737-400 series airplanes, specifically line numbers 1487 through 3132, must perform repetitive inspections as specified in Boeing Alert Requirements Bulletin 737-53A1380 RB starting from the effective date. Any detected cracking must be repaired before further flight using FAA-approved methods. Compliance with this directive is mandatory by April 8, 2019, the effective date of the AD.

Summary

Federal Register Volume 84, Number 42 (March 4, 2019) Final Rule titled 'Fuselage - Overwing Emergency Exit Doors - Inspection' is an airworthiness directive issued by the FAA for certain Boeing 737-400 series airplanes. It addresses cracking found in the splice plate on the lower sill of the overwing emergency exit doors. The directive mandates repetitive inspections and necessary repairs to ensure continued structural integrity.

What changed

This new airworthiness directive introduces mandatory repetitive high frequency eddy current inspections for cracking in the splice plate of the overwing emergency exit door lower sill on Boeing 737-400 series airplanes. It also requires applicable on-condition corrective actions if cracking is found. The directive incorporates Boeing Alert Requirements Bulletin 737-53A1380 RB dated July 18, 2018, as the service information for compliance.

Why it matters

This directive is critical for aviation professionals because undetected cracking in the splice plate could compromise a principal structural element, potentially leading to rapid decompression of the fuselage. Operators and maintenance organizations must ensure compliance to maintain aircraft airworthiness and passenger safety. The inspections and repairs help prevent structural failures and avoid costly unscheduled maintenance or safety incidents.

What to do

Summary

What changed

Why it matters

More for Boeing 737