Narrative:

Loss of cabin pressure on takeoff and climb out. Crew suspected faulty ground shift but had no indication of any malfunction through the aircraft warning system. We ran many different cockpit operating procedures from our company's manual to no avail. Burned off fuel to be at maximum landing weight or under and landed normally after declaring an emergency. Loud air noise caused us to suspect a damaged door/seal or hole in skin. Maintenance found an inoperative door micro switch, and bad seal/door on belly, of electronics bay. MEL deferred door annunciator to repair it later, and we departed, again.

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Original NASA ASRS Text

Title: A DC9 ON CLIMB OUT AT 5000 FT DECLARED AN EMERGENCY AND DIVERTED DUE TO LOSS OF CABIN PRESSURE. CAUSED BY A DEFECTIVE ELECTRONICS BAY DOOR SEAL.

Narrative: LOSS OF CABIN PRESSURE ON TKOF AND CLIMB OUT. CREW SUSPECTED FAULTY GND SHIFT BUT HAD NO INDICATION OF ANY MALFUNCTION THROUGH THE ACFT WARNING SYS. WE RAN MANY DIFFERENT COCKPIT OPERATING PROCS FROM OUR COMPANY'S MANUAL TO NO AVAIL. BURNED OFF FUEL TO BE AT MAX LANDING WEIGHT OR UNDER AND LANDED NORMALLY AFTER DECLARING AN EMER. LOUD AIR NOISE CAUSED US TO SUSPECT A DAMAGED DOOR/SEAL OR HOLE IN SKIN. MAINT FOUND AN INOPERATIVE DOOR MICRO SWITCH, AND BAD SEAL/DOOR ON BELLY, OF ELECTRONICS BAY. MEL DEFERRED DOOR ANNUNCIATOR TO REPAIR IT LATER, AND WE DEPARTED, 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.