Narrative:

After takeoff the passenger door not latched caution message came on. Then shortly after, the passenger door warning message and 'door' aural came on. At that point we requested a leveloff at 6000 ft. The first officer (PNF) pulled out the emergency checklist and I (the captain/PF) took over radio communications. I declared an emergency and informed ATC of our problem and the need to return for a landing. The first officer and I went over the emergency checklist items. The first action for an in-flight door warning is to depressurize the aircraft. I elected to not follow this procedure for several reasons. This aircraft type has a history of false door warnings. To my knowledge, every passenger door warning has been a false warning. When the emergency procedure has been blindly followed, the result has been passenger and crew being injured from the rapid depressurization. The first officer informed the flight attendant of our problem. She said that the door alignment markings that she could see from her seat were all aligned. Because we did not receive any other indications that the door was unsecured, ie, noise from the door, pressurization problems, other door cautions, the emergency procedure was not precisely followed. Instead, I elected to reduce our airspeed and descend. The return and landing were uneventful. The door warning and caution went out shortly after touchdown. This problem is discussed in our annual recurrent ground school. A revised checklist is needed as well as further or improved door alert/warning system.

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Original NASA ASRS Text

Title: A CANADAIR CL65 IN CLB AT 6000 FT DECLARED AN EMER AND DIVERTED DUE TO A PAX DOOR WARNING.

Narrative: AFTER TKOF THE PAX DOOR NOT LATCHED CAUTION MESSAGE CAME ON. THEN SHORTLY AFTER, THE PAX DOOR WARNING MESSAGE AND 'DOOR' AURAL CAME ON. AT THAT POINT WE REQUESTED A LEVELOFF AT 6000 FT. THE FO (PNF) PULLED OUT THE EMER CHKLIST AND I (THE CAPT/PF) TOOK OVER RADIO COMS. I DECLARED AN EMER AND INFORMED ATC OF OUR PROB AND THE NEED TO RETURN FOR A LNDG. THE FO AND I WENT OVER THE EMER CHKLIST ITEMS. THE FIRST ACTION FOR AN INFLT DOOR WARNING IS TO DEPRESSURIZE THE ACFT. I ELECTED TO NOT FOLLOW THIS PROC FOR SEVERAL REASONS. THIS ACFT TYPE HAS A HISTORY OF FALSE DOOR WARNINGS. TO MY KNOWLEDGE, EVERY PAX DOOR WARNING HAS BEEN A FALSE WARNING. WHEN THE EMER PROC HAS BEEN BLINDLY FOLLOWED, THE RESULT HAS BEEN PAX AND CREW BEING INJURED FROM THE RAPID DEPRESSURIZATION. THE FO INFORMED THE FLT ATTENDANT OF OUR PROB. SHE SAID THAT THE DOOR ALIGNMENT MARKINGS THAT SHE COULD SEE FROM HER SEAT WERE ALL ALIGNED. BECAUSE WE DID NOT RECEIVE ANY OTHER INDICATIONS THAT THE DOOR WAS UNSECURED, IE, NOISE FROM THE DOOR, PRESSURIZATION PROBS, OTHER DOOR CAUTIONS, THE EMER PROC WAS NOT PRECISELY FOLLOWED. INSTEAD, I ELECTED TO REDUCE OUR AIRSPD AND DSND. THE RETURN AND LNDG WERE UNEVENTFUL. THE DOOR WARNING AND CAUTION WENT OUT SHORTLY AFTER TOUCHDOWN. THIS PROB IS DISCUSSED IN OUR ANNUAL RECURRENT GND SCHOOL. A REVISED CHKLIST IS NEEDED AS WELL AS FURTHER OR IMPROVED DOOR ALERT/WARNING SYS.

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.