Narrative:

On an IFR flight from ZZZ to ZZZ1 while climbing through FL270 for FL290; I heard a bang and felt a rapid decompression. I turned off the airway to the east while descending. Through the excitement and while having to talk to passenger; I was unable to speak to controllers until I got everything under control. It was probably at an altitude of about FL180 to FL190 that I finally called center. They treated it very calmly and just asked if we needed anything. They said that they didn't even need a letter about what happened. The aircraft is being repaired at ZZZ1. They found that a bolt had hollowed out and weakened the strength of the bayonet rods on the upper right side of the door; allowing it to pop open once the psi differential got to its maximum. No one was hurt and we cruised on to ZZZ1 at 11000 ft. Callback conversation with reporter revealed the following information: reporter indicated this is an older BE350; but reporter and beechcraft are unaware of any other similar problems.

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Original NASA ASRS Text

Title: A BE350 CAPTAIN CLIMBING THROUGH 27500 FT EXPERIENCED A RAPID DECOMPRESSION.

Narrative: ON AN IFR FLT FROM ZZZ TO ZZZ1 WHILE CLBING THROUGH FL270 FOR FL290; I HEARD A BANG AND FELT A RAPID DECOMPRESSION. I TURNED OFF THE AIRWAY TO THE E WHILE DSNDING. THROUGH THE EXCITEMENT AND WHILE HAVING TO TALK TO PAX; I WAS UNABLE TO SPEAK TO CTLRS UNTIL I GOT EVERYTHING UNDER CTL. IT WAS PROBABLY AT AN ALT OF ABOUT FL180 TO FL190 THAT I FINALLY CALLED CTR. THEY TREATED IT VERY CALMLY AND JUST ASKED IF WE NEEDED ANYTHING. THEY SAID THAT THEY DIDN'T EVEN NEED A LETTER ABOUT WHAT HAPPENED. THE ACFT IS BEING REPAIRED AT ZZZ1. THEY FOUND THAT A BOLT HAD HOLLOWED OUT AND WEAKENED THE STRENGTH OF THE BAYONET RODS ON THE UPPER R SIDE OF THE DOOR; ALLOWING IT TO POP OPEN ONCE THE PSI DIFFERENTIAL GOT TO ITS MAX. NO ONE WAS HURT AND WE CRUISED ON TO ZZZ1 AT 11000 FT. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: REPORTER INDICATED THIS IS AN OLDER BE350; BUT REPORTER AND BEECHCRAFT ARE UNAWARE OF ANY OTHER SIMILAR PROBLEMS.

Data retrieved from NASA's ASRS site as of January 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.