Narrative:

After departing and during initial climb; the master warning annunciator sounded and illuminated and the fuselage doors warning annunciator also illuminated. Simultaneously the aircraft lost all pressurization. This occurred at approximately 1;000-1;500 ft MSL. We (the crew) subsequently went to the doors page of the mfd and confirmed that the aft baggage door was annunciating an unsafe condition. I called for the QRH for fuselage doors and the first officer performed and completed the QRH checklist. During which time we informed the tower of the problem and requested vectors back to the departure airport for the air return. Since the aircraft lost pressurization immediately upon the activation of the master warning; as well as a very rapid de-pressurization; I decided to declare the emergency and request priority handling from the tower. I also informed the flight attendants of the nature of the emergency and that we would be returning back to the departure airport. I then made a PA informing the passengers of the problem and that we would be returning back to the airport. The flight crew prepared the aircraft for landing by obtaining the appropriate performance data and performing and descent and before landing checklist. It was also determined that the aircraft was not over its max landing weight limits of 62;000 pounds. I executed a visual approach to runway 25 and landed without incident. Upon reaching the gate after the air return; it was discovered that the aft baggage door handle had popped out and triggered the annunciators. Apparently; through a mechanic's inspection; he had determined that the baggage door handle had not been completed closed by the ground handling crew. It is my understanding that this issue has occurred a number of times before; mainly in stations new to handling this particular aircraft. Proper and thorough training with respect to this door issue should be paramount.

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Original NASA ASRS Text

Title: A Q400's door warning indicated the aft cargo door was open climbing through about 1;500 FT after takeoff. An emergency was declared and the crew returned to the departure airport where it was determined that Ground Personnel had not properly closed the door.

Narrative: After departing and during initial climb; the master warning annunciator sounded and illuminated and the fuselage doors warning annunciator also illuminated. Simultaneously the aircraft lost all pressurization. This occurred at approximately 1;000-1;500 FT MSL. We (the crew) subsequently went to the doors page of the MFD and confirmed that the aft baggage door was annunciating an unsafe condition. I called for the QRH for fuselage doors and the First Officer performed and completed the QRH checklist. During which time we informed the Tower of the problem and requested vectors back to the departure airport for the air return. Since the aircraft lost pressurization immediately upon the activation of the Master Warning; as well as a very rapid de-pressurization; I decided to declare the emergency and request priority handling from the Tower. I also informed the flight attendants of the nature of the emergency and that we would be returning back to the departure airport. I then made a PA informing the passengers of the problem and that we would be returning back to the airport. The flight crew prepared the aircraft for landing by obtaining the appropriate performance data and performing and descent and before landing checklist. It was also determined that the aircraft was not over its max landing weight limits of 62;000 LBS. I executed a visual approach to Runway 25 and landed without incident. Upon reaching the gate after the air return; it was discovered that the aft baggage door handle had popped out and triggered the annunciators. Apparently; through a mechanic's inspection; he had determined that the baggage door handle had not been completed closed by the ground handling crew. It is my understanding that this issue has occurred a number of times before; mainly in stations new to handling this particular aircraft. Proper and thorough training with respect to this door issue should be paramount.

Data retrieved from NASA's ASRS site as of April 2012 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.