Action
Final rule.
Summary
We are adopting a new airworthiness directive (AD) for certain ATR-GIE Avions de Transport R[eacute]gional Model ATR42-500 airplanes and Model ATR72-102, -202, -212, and -212A airplanes. This AD was prompted by reports of failure of emergency power supply units (EPSUs) in production and in service. This AD requires an inspection to determine the part number and serial number of each EPSU, and replacement if necessary. We are issuing this AD to address the unsafe condition on these products.