What was found
DURING CRUISE AT 14,000 FEET, LT FORWARD CABIN WINDOW BLEW OUT. UPON INSPECTION OF REMAINING CABIN WINDOWS, ALL EXCEPT ONE HAD CRACKS AROUND ENTIRE CIRCUMFERENCE. THESE CRACKS WERE IN AND PARALLEL TO THE RADIUSED AREA WHERE THE WINDOW IS MACHINED TO FIT THE CUT OUT AREA IN THE FUSELAGE. THESE WINDOWS ARE USED ON VARIOUS MODELS OF THE KING AIR FROM 90 THROUGH 350 MODELS. THE SAME PART NUMBER IS REFERRED TO IN EACH MANUAL FOR THESE DIFFERENT AIRCRAFT.