Narrative:

Took off, entered IMC. Alternator warning lights came on, I requested vectors for landing. Received vector for return and then the door opened. Because of combination of factors I declared emergency. Landing was uneventful and safe. I (pilot) neglected to check that door was properly closed after my wife (passenger) closed it. Because she had closed the door on many prior flts, I had become complacent about checking. That will not happen again.

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Original NASA ASRS Text

Title: PLT OF BE55 DEPARTS AND ENTERS IMC. THE ALTERNATOR WARNING LIGHTS ACTIVATE. DURING RETURN TO LAND THE ACFT DOOR OPENS.

Narrative: TOOK OFF, ENTERED IMC. ALTERNATOR WARNING LIGHTS CAME ON, I REQUESTED VECTORS FOR LNDG. RECEIVED VECTOR FOR RETURN AND THEN THE DOOR OPENED. BECAUSE OF COMBINATION OF FACTORS I DECLARED EMER. LNDG WAS UNEVENTFUL AND SAFE. I (PLT) NEGLECTED TO CHK THAT DOOR WAS PROPERLY CLOSED AFTER MY WIFE (PAX) CLOSED IT. BECAUSE SHE HAD CLOSED THE DOOR ON MANY PRIOR FLTS, I HAD BECOME COMPLACENT ABOUT CHKING. THAT WILL NOT HAPPEN AGAIN.

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.