EASA AD US-2021-23-08
Wings - Center Wing Mid Spar Splice Plate - Repetitive Inspections
Summary
The FAA Airworthiness Directive 2021-23-08 is a final rule addressing certain Learjet Inc. Model 45 series airplanes, including Learjet 40, 45, 70, and 75. It mandates repetitive inspections of the center wing mid spar splice plate for corrosion and deterioration of protective treatments. This directive aims to prevent potential wing centerline joint failure due to corrosion.
What Changed
This new airworthiness directive introduces mandatory repetitive inspections of the center wing area for corrosion and protective treatment deterioration on specified Learjet Model 45 airplanes. It requires removal of any corrosion found and treatment of deteriorated areas. Additionally, credit is provided for previous inspections performed under Inspection Reference Number 5710190.
Why It Matters
This directive is critical for aviation professionals because corrosion in the center wing mid spar splice plate can lead to partial wing separation and loss of airplane control. Operators and maintenance organizations must ensure ongoing compliance to maintain aircraft structural integrity and flight safety. Early detection and treatment of corrosion reduce the risk of costly repairs and enhance operational reliability.
What To Do
Affected operators must perform repetitive inspections of the center wing area for corrosion and protective treatment deterioration using the specified Bombardier Learjet service bulletins. Any corrosion must be removed and deteriorated areas treated promptly. Compliance with this directive is required starting January 10, 2022, and credit is allowed for prior inspections using IRN 5710190.
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