Narrative:

Before pushing back from the gate, maintenance was working in the equipment bay to troubleshoot an electrical problem. After completing the problem they closed the door, which is a few ft aft of the nose wheel of the aircraft. The light in the cockpit remained on, however, after the door was closed. I asked them to rechk the door to confirm it was closed. After rechking the door maintenance confirmed it was closed. We pushed back and taxied out for a normal departure. After takeoff and the landing gear retracted, a very loud noise became apparent as we increased our airspeed. The noise became louder to the point that conversation in the cockpit was impossible. The aircraft would not pressurize. I immediately assessed the problem that the equipment door somehow was not completely closed and that was causing the loud air noise and pressurization problem we were having. We leveled off at 2000' and requested a return to the airport. The return was normal. We taxied back to the gate. The equipment door was rechked by maintenance and although the door was secure, the seal around it was not. The seal was publication back in place, which put the door light out in the cockpit and the flight was continued normally.

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Original NASA ASRS Text

Title: MAINT CLOSED EQUIPMENT BAY DOOR, BUT FLT CREW UNABLE TO PRESSURIZE AFTER TKOF WITH EVIDENT AIR NOISE RETURNED. LANDED. MAINTENANCE ADJUSTED SEAL AROUND DOOR.

Narrative: BEFORE PUSHING BACK FROM THE GATE, MAINT WAS WORKING IN THE EQUIP BAY TO TROUBLESHOOT AN ELECTRICAL PROB. AFTER COMPLETING THE PROB THEY CLOSED THE DOOR, WHICH IS A FEW FT AFT OF THE NOSE WHEEL OF THE ACFT. THE LIGHT IN THE COCKPIT REMAINED ON, HOWEVER, AFTER THE DOOR WAS CLOSED. I ASKED THEM TO RECHK THE DOOR TO CONFIRM IT WAS CLOSED. AFTER RECHKING THE DOOR MAINT CONFIRMED IT WAS CLOSED. WE PUSHED BACK AND TAXIED OUT FOR A NORMAL DEP. AFTER TKOF AND THE LNDG GEAR RETRACTED, A VERY LOUD NOISE BECAME APPARENT AS WE INCREASED OUR AIRSPD. THE NOISE BECAME LOUDER TO THE POINT THAT CONVERSATION IN THE COCKPIT WAS IMPOSSIBLE. THE ACFT WOULD NOT PRESSURIZE. I IMMEDIATELY ASSESSED THE PROB THAT THE EQUIP DOOR SOMEHOW WAS NOT COMPLETELY CLOSED AND THAT WAS CAUSING THE LOUD AIR NOISE AND PRESSURIZATION PROB WE WERE HAVING. WE LEVELED OFF AT 2000' AND REQUESTED A RETURN TO THE ARPT. THE RETURN WAS NORMAL. WE TAXIED BACK TO THE GATE. THE EQUIP DOOR WAS RECHKED BY MAINT AND ALTHOUGH THE DOOR WAS SECURE, THE SEAL AROUND IT WAS NOT. THE SEAL WAS PUB BACK IN PLACE, WHICH PUT THE DOOR LIGHT OUT IN THE COCKPIT AND THE FLT WAS CONTINUED NORMALLY.

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.