EASA AD CF-1997-18R1
CANCELLED: Main Rotor System — Cracking of Rotor Mast
Summary
The document titled CANCELLED: Main Rotor System — Cracking of Rotor Mast is a Canadian Airworthiness Directive (CF-97-18) issued by Transport Canada. It applies to all Eurocopter Canada Ltd. BO 105LS A-3 model helicopters and addresses critical cracking found on the main rotor mast flange. The directive mandates repetitive visual inspections to detect cracks to ensure continued airworthiness.
What Changed
This directive introduced mandatory repetitive visual inspections of the main rotor mast flange using a 10x magnifying glass to detect cracks. It was issued following the discovery of critical cracks on similar Eurocopter Deutschland BO 105 rotor masts, extending the inspection requirement to the BO 105LS A-3 helicopters due to component similarity. The directive requires reporting any cracks found to Transport Canada and Eurocopter Canada.
Why It Matters
This directive is crucial for aviation professionals to prevent potential failure of the main rotor mast flange, which could lead to catastrophic helicopter failure. Operators and maintenance organizations must comply to maintain the aircraft's airworthiness and flight authority under Canadian regulations. Early detection of cracks ensures timely corrective actions, enhancing flight safety and regulatory compliance.
What To Do
Operators of Eurocopter Canada BO 105LS A-3 helicopters must perform a visual inspection of the main rotor mast flange using a 10x magnifying glass at the first flight after the directive's effective date and subsequently every 100 flight hours. Any detected cracks must be reported to Transport Canada via a service difficulty report and to Eurocopter Canada. Alternative compliance methods require prior approval from the Director of Aircraft Certification at Transport Canada.
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