Narrative:

Approximately 1 hour after departure the flight attendant notified me that the access door from the lavatory to the cargo compartment was ajar. I instructed the first officer to investigate the situation. When he returned I was informed that the cargo access door had, what appeared to be, a manufacturer defect. The latch did not align with the lock. We assumed that the access door opened from fuselage flexing during flight. I instructed the flight attendant to inform me of any passenger that used the lavatory while we evaluated the situation. After approximately 2 mins she informed me that 2 passenger, in the back, had used the lavatory more than once and that one of them was at that time in the lavatory. I then instructed her to 'seal' and not to allow any further use of the lavatory. Meanwhile, the first officer and I continued to evaluate the situation and found that all that we had was an open access door, with no evidence of tampering, and a couple of passenger who appeared normal other than using the lavatory more than once.

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Original NASA ASRS Text

Title: ACCESS DOOR TO CARGO COMPARTMENT FROM LAVATORY TO CARGO COMPARTMENT FOUND AJAR.

Narrative: APPROX 1 HR AFTER DEP THE FLT ATTENDANT NOTIFIED ME THAT THE ACCESS DOOR FROM THE LAVATORY TO THE CARGO COMPARTMENT WAS AJAR. I INSTRUCTED THE FO TO INVESTIGATE THE SITUATION. WHEN HE RETURNED I WAS INFORMED THAT THE CARGO ACCESS DOOR HAD, WHAT APPEARED TO BE, A MANUFACTURER DEFECT. THE LATCH DID NOT ALIGN WITH THE LOCK. WE ASSUMED THAT THE ACCESS DOOR OPENED FROM FUSELAGE FLEXING DURING FLT. I INSTRUCTED THE FLT ATTENDANT TO INFORM ME OF ANY PAX THAT USED THE LAVATORY WHILE WE EVALUATED THE SITUATION. AFTER APPROX 2 MINS SHE INFORMED ME THAT 2 PAX, IN THE BACK, HAD USED THE LAVATORY MORE THAN ONCE AND THAT ONE OF THEM WAS AT THAT TIME IN THE LAVATORY. I THEN INSTRUCTED HER TO 'SEAL' AND NOT TO ALLOW ANY FURTHER USE OF THE LAVATORY. MEANWHILE, THE FO AND I CONTINUED TO EVALUATE THE SITUATION AND FOUND THAT ALL THAT WE HAD WAS AN OPEN ACCESS DOOR, WITH NO EVIDENCE OF TAMPERING, AND A COUPLE OF PAX WHO APPEARED NORMAL OTHER THAN USING THE LAVATORY MORE THAN ONCE.

Data retrieved from NASA's ASRS site as of July 2007 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.