The European Aviation Safety Agency (EASA) has issued an emergency airworthiness directive (AD) for ATR cockpit windows. AD Number 2009-0159-E requires inspection and, if necessary, replacement of  cockpit forward-side windows on ATR models 42-200, 42-300, 42-320, 42-400 and 42-500, and 72-101, 72-102, 72-201, 72-202, 72-211, 72-212 and 72-212A equipped with PPG Aerospace glass windows. The inspection must be completed within 10 days after accumulation of 2,000 total flight cycles on a given cockpit forward-side window, or within 10 days after July 20, 2009, the effective date of the AD, for windows that have accumulated 2,000 or more total flight cycles . The reason for the AD is a recent event in which a left hand, forward side glass window of an ATR 72-212 blew out while the airplane was performing a ground pressure test. The investigation revealed some anomalies on the forward side window at the level of the z-bar on the window’s external side and at the level of the inner retainer on the window’s internal side considered precursors of the failure. Neither ATR nor PPG Aerospace authorizes repairs.