Narrative:

Upon rotation/climbing off the runway, I heard a sound that I thought was an air leak. The noise became progressively louder and higher in pitch as time passed. The aircraft leveled off and I received a crew call on the interphone from the first officer (copilot), stating they were having trouble sealing/pressurizing the aircraft for flight. He said we would be returning to miami. I was having difficulty hearing him, so I briefed the passenger, assuming that an announcement from the cockpit was not possible. Once we landed and returned to the gate, maintenance boarded the aircraft and, in examining the captain's port side window, discovered a pen lodged in the window track. I later learned that we reached a maximum altitude of 3000 ft before descending back into miami. We took off and flew to boston without further incident less than 1 hour later. The small plastic pen was the cause of the problem.

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Original NASA ASRS Text

Title: RETURN LAND MANDATED FOR AN A300-600 FLT WHEN THE CREW IS UNABLE TO PRESSURIZE THE ACFT AFTER TKOF FROM MIA, FL.

Narrative: UPON ROTATION/CLBING OFF THE RWY, I HEARD A SOUND THAT I THOUGHT WAS AN AIR LEAK. THE NOISE BECAME PROGRESSIVELY LOUDER AND HIGHER IN PITCH AS TIME PASSED. THE ACFT LEVELED OFF AND I RECEIVED A CREW CALL ON THE INTERPHONE FROM THE FO (COPLT), STATING THEY WERE HAVING TROUBLE SEALING/PRESSURIZING THE ACFT FOR FLT. HE SAID WE WOULD BE RETURNING TO MIAMI. I WAS HAVING DIFFICULTY HEARING HIM, SO I BRIEFED THE PAX, ASSUMING THAT AN ANNOUNCEMENT FROM THE COCKPIT WAS NOT POSSIBLE. ONCE WE LANDED AND RETURNED TO THE GATE, MAINT BOARDED THE ACFT AND, IN EXAMINING THE CAPT'S PORT SIDE WINDOW, DISCOVERED A PEN LODGED IN THE WINDOW TRACK. I LATER LEARNED THAT WE REACHED A MAX ALT OF 3000 FT BEFORE DSNDING BACK INTO MIAMI. WE TOOK OFF AND FLEW TO BOSTON WITHOUT FURTHER INCIDENT LESS THAN 1 HR LATER. THE SMALL PLASTIC PEN WAS THE CAUSE OF THE PROB.

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.