WINDOW AND DOOR BLOW OUT DURING FLT.

Narrative

THE FLT HAD COMPLETED A SERIES OF 5 SELECTED AEROBATIC SEQUENCES INVOLVING LOOPS; SLOW ROLLS; SPLIT S; HAMMERHEAD TURNS; SPINS; 4 POINT ROLL; CLOVERLEAF; AND HORIZ 8'S. THE CREW THEN BEGAN A REVIEW OF SELECTED MANEUVERS WHICH HAD NOT BEEN ACCOMPLISHED IN THE SEQUENCES. WHEN PERFORMING THE SECOND SLOW ROLLING TURN; AS THE ACFT APCHED THE R KNIFE EDGE THE CABIN DOOR WINDOW BLEW OUT AND THE UPPER HALF OF THE DOOR BROKE. IT IS BELIEVED THAT THE UPPER DOOR LATCHES RELEASED DURING THE ROLL. INSPECTION/REPLACEMENT OF THE LATCHES ON. EACH PHASE MAY HAVE PREVENTED THEM FROM OPENING; DUE TO EXCESSIVE WEAR/LOOSING. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: DURING CALLBACK PLT BETTER DESCRIBED HOW DOOR AND WINDOW FLEX OUTWARD ANYTIME THE FUSELAGE IS IN A KNIFE EDGE MANEUVER. THE TOP SIDE OF THE FUSELAGE DURING THE MANEUVER ALWAYS FLEX IN AND OUT SEVERAL TIMES DURING THE WING'S VERT POS. THE DOOR HAS 2 OTHER LATCHES THAT HOLD THE DOOR CLOSED BESIDES THE LATCH FOR ENTRY INTO THE ACFT. APPARENTLY AS THE ACFT AGES FROM AEROBATIC MANEUVERING; THESE LATCHES CAN FAIL FROM THE STRESS PLACED ON THEM FROM SEVERAL FLTS.