The eddy current inspection used on VH-TZJ, and other M18 aircraft, had not been approved by the Civil Aviation Safety Authority as an alternate means of compliance to airworthiness directive AD/PZL/5. This exposed those aircraft to an inspection method that was potentially ineffective at detecting cracks in the wing attachment fittings.
The ATSB is satisfied that the actions taken by CASA address the safety risk associated with this issue.
On 15 November 2013, the Civil Aviation Safety Authority (CASA) issued an amendment to airworthiness directive AD/PZL/5, revoking the approval for the eddy current procedure to be used for M18 wing joint inspections. It also added a 100‑hourly visual inspection, and additional wing-off inspections in M18 aircraft every 2,500 hours. CASA also issued a direction to all registered operators of M18 aircraft in Australia that the aircraft could be flown after compliance with the amended AD.
On 22 November 2013, CASA issued AD/PZL/5 Amendment 2, to additionally require: