Narrative:

In cruise flight, we received a master warning annunciator for cabin door insecure. We immediately informed ATC and made a precautionary landing in groton, ct. The first officer insured that the door was secure prior to flight. Therefore, there was really nothing that could have been done to prevent this incident. However, we should have declared an emergency. That is the only thing that I would have done differently.

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Original NASA ASRS Text

Title: FLC OF A BEECH 1900 AIRLINER DIVERTED TO ANOTHER ARPT TO MAKE A PRECAUTIONARY LNDG DUE TO A CABIN DOOR WARNINGS.

Narrative: IN CRUISE FLT, WE RECEIVED A MASTER WARNING ANNUNCIATOR FOR CABIN DOOR INSECURE. WE IMMEDIATELY INFORMED ATC AND MADE A PRECAUTIONARY LNDG IN GROTON, CT. THE FO INSURED THAT THE DOOR WAS SECURE PRIOR TO FLT. THEREFORE, THERE WAS REALLY NOTHING THAT COULD HAVE BEEN DONE TO PREVENT THIS INCIDENT. HOWEVER, WE SHOULD HAVE DECLARED AN EMER. THAT IS THE ONLY THING THAT I WOULD HAVE DONE DIFFERENTLY.

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.