EASA today issued an emergency AD calling for inspections of ATR-series cockpit forward side window sealant after a recent failure of a window on an ATR 72 during a ground pressurization test. From the AD:
The investigation revealed some anomalies on the forward side window at the level of the z-bar on the windows external side and at the level of the inner retainer on the windows internal side. These anomalies are considered as precursors of this failure.
EASA notes that signs of air or water leakage mean the windows must be replaced; repairing the sealant "could lead to a similar event that has originated this AD."
The AD covers aircraft with at least 2,000 cycles. Operators have 10 days to check their aircraft; acrylic-based windows are not covered.
Window manufacturer PPG Aerospace issued a service bulletin on July 8 addressing the issue.