EASA AD US-2022-25-01
Wings - Center Wing Box Rear Spar and Lower Skin - Inspection
Summary
The Federal Aviation Administration's Airworthiness Directive 2022-25-01 addresses structural cracking issues in the center wing box rear spar and lower skin on all Boeing Model 707 and Model 727 airplanes. This directive requires repetitive inspections and sealant applications to detect and mitigate cracking that could compromise the structural integrity of these aircraft. The AD was prompted by findings of similar cracking on a Boeing Model 737-300 airplane and a cross-model review indicating susceptibility in the 707 and 727 models.
What Changed
This new airworthiness directive introduces mandatory repetitive detailed inspections, including high frequency eddy current and ultrasonic inspections, of the center wing box lower skin and rear spar lower chord for cracking on Boeing 707 and 727 airplanes. It also requires repetitive sealant applications and necessary repairs to address detected cracks. The AD establishes specific compliance times and inspection procedures based on Boeing Alert Requirements Bulletins.
Why It Matters
This directive is critical for aviation professionals as it addresses a structural safety concern that could lead to failure of the wing box and rear spar components, potentially compromising the aircraft's ability to sustain limit loads. Operators and maintenance organizations must implement these inspections and repairs to maintain airworthiness and ensure continued safe operation of affected Boeing 707 and 727 airplanes. Compliance with this AD helps prevent costly structural failures and enhances overall fleet safety.
What To Do
Operators of Boeing 707 and 727 airplanes must perform repetitive detailed inspections of the center wing box lower skin and rear spar lower chord as specified in the Boeing Alert Requirements Bulletins. Sealant applications and repairs must be conducted as necessary based on inspection findings. For Group 1 Model 727 airplanes, inspections and any required corrective actions must be completed within 120 days of the AD's effective date, February 16, 2023. Other affected airplanes must comply according to the specified intervals in the service bulletins.
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