COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Bell Helicopter Textron 212 Series Helicopters AD/BELL 212/3 Amdt 5 Main Rotor Blades - Eddy Current Inspection 12/84 Applicability: All models with main rotor blades P/N 204-012-001. Requirement: 1. Inspect the upper and lower surface of each blade by means of an approved low frequency eddy current technique in order to detect fatigue cracking in the blade spar prior to its propagation into the skin material. The areas to be inspected are the upper and lower sections of the spar extending forward approximately 0.5 inches and along a line approximately 4.0 inches, from the rear vertical face. As far as is practicable and excluding the inboard end doubler and tip weight areas, the complete length of each blade is to be covered. Note: Eddy Current Technique ATG/NDI/EC3 is approved for this inspection. 2. By means of an approved eddy current technique inspect the main rotor blade upper and lower skins between the spar and the trailing edge member for fatigue cracking. Two approximately equally spaced scans are required on each surface. Compliance: Prior to achieving 300 hours component time in service and thereafter at intervals not exceeding 25 hours component time in service. Background: This Directive has been revised to exclude the later model glass fibre belted blades from the requirement.