Airworthiness Directives; AeroSpace Technologies of Australia Pty Ltd. Models N22B and N24A Airplanes

This amendment supersedes Airworthiness Directive (AD) 82-12- 06, which applies to certain AeroSpace Technologies of Australia Pty Ltd. (ASTA) Models N22B and N24A airplanes. AD 82-12-06 currently requires repetitive visual inspections of all rudder control lever shaft assemblies for cracks and discrepancies, and, if cracks or discrepancies are found, it requires replacement with new or serviceable rudder control shafts, and a check of the fit of all rod end bearings in lever shafts. AD 82-12-06 also allows you to inspect all lever shafts by magnetic particle inspection or dye penetrant methods as terminating action for the repetitive visual inspections. This AD is the result of recent reports of failures of the upper control lever torque shaft due to fatigue loading on the affected airplanes, including those that included the terminating actions. This AD requires more detailed repetitive inspections (than there are in AD 82-12-06) of the upper and lower rudder pedal torque shafts and a one- time inspection for discrepancies in the thickness of the lever shaft side plates with appropriate follow-up action. The actions specified by this AD are intended to detect and correct cracks in the rudder control lever torque shafts and discrepancies in the thickness of the lever shaft side plates, which could result in failure of the rudder control lever torque shaft. Such failure could lead to reduced controllability of the airplane.