Narrative:

On climb out; noticed loud noise from main cabin door. Looked at cabin altitude and rate on EICAS. Noticed that rate was zero and cabin altitude was 2000-3000 ft. Captain decided to return to ZZZ. On downwind; cabin rate started to fluctuate rapidly; then stabilized at zero. Landed with crash fire rescue equipment. They noticed that door flap did not appear to be closed all the way. When parked and door was opened at gate; ramp crew noticed that a small piece of material fell from the door onto the ramp.

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Original NASA ASRS Text

Title: A CRJ200 ON CLBOUT HAD A LOUD NOISE FROM THE MAIN CABIN DOOR. CREW NOTED CABIN CLBING WITH AIRPLANE. ON GND; FOUND SMALL PIECE OF MATERIAL BLOCKING DOOR FLAP.

Narrative: ON CLBOUT; NOTICED LOUD NOISE FROM MAIN CABIN DOOR. LOOKED AT CABIN ALT AND RATE ON EICAS. NOTICED THAT RATE WAS ZERO AND CABIN ALT WAS 2000-3000 FT. CAPT DECIDED TO RETURN TO ZZZ. ON DOWNWIND; CABIN RATE STARTED TO FLUCTUATE RAPIDLY; THEN STABILIZED AT ZERO. LANDED WITH CFR. THEY NOTICED THAT DOOR FLAP DID NOT APPEAR TO BE CLOSED ALL THE WAY. WHEN PARKED AND DOOR WAS OPENED AT GATE; RAMP CREW NOTICED THAT A SMALL PIECE OF MATERIAL FELL FROM THE DOOR ONTO THE RAMP.

Data retrieved from NASA's ASRS site as of January 2009 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.