Airworthiness Directives; ATR-GIE Avions de Transport Régional Airplanes

The FAA is superseding Airworthiness Directive (AD) 2021-10- 20, which applied to certain ATR-GIE Avions de Transport R[eacute]gional Model ATR42-500 and ATR72-212A airplanes. AD 2021-10-20 required revising the existing aircraft flight manual (AFM) and applicable corresponding operational procedures to update a systems limitation, limiting dispatch with certain equipment inoperative, performing an operational test of a certain contactor and an electrical test of a certain battery toggle switch, and performing corrective actions if necessary. This AD was prompted by new procedures for modifying the wiring and replacing the battery toggle switch that have been developed that would terminate the AD requirements. This AD continues to require certain actions in AD 2021-10-20, and requires modifying the battery toggle switch wiring and replacing the battery toggle switch, and revises the applicability to include additional airplanes, as specified in a European Union Aviation Safety Agency (EASA) AD, which is incorporated by reference. This AD also prohibits the installation of affected parts. The FAA is issuing this AD to address the unsafe condition on these products.