Pressurized Window Failure at Flight Level 180 (N85BH)

What happened

While the aircraft was cruising at an altitude of 18,000 feet, the pilot reported that the pressurized portion of the second window failed catastrophically and blew out. Despite this sudden loss of the outer pane, the inside window remained intact, which allowed the cabin to depressurize slowly rather than experiencing a rapid decompression event. The pilot maintained control of the aircraft and executed an uneventful landing without further incident.

The investigation

Following the incident, the failed window component was examined. It was determined that the old window had accumulated approximately 5773 hours since its installation. To resolve the issue, the defective pane was replaced with a later production version of the window assembly. After the replacement and necessary inspections, the aircraft was released back into service for flight operations.