Narrative:

During climb out; the lead flight attendant informed me of excessive floor vibration and loud noise in the forward galley area. I asked her to have another flight attendant to verify and advise me of what she heard. After their reports; I went to the forward galley and heard/felt the noise/vibration. Upon return to the cockpit and after discussion with the first officer; I believed that the noise/vibration was increasing with the aircraft's increasing speed. I had the first officer slow to 250 KTS and obtained ATC clearance to return to the departure airport. Our arrival gross weight exceeded the maximum landing weight; so I briefed the crew of our need to declare an emergency; briefed the flight attendants and informed the passengers. We ran the QRH over-weight landing checklist and notified dispatch. ATC was informed of our emergency status and told us crash fire rescue equipment was standing by. I transitioned to pilot flying; landed the aircraft and; after being told the aircraft appeared normal; taxied to the gate. After gate arrival; maintenance informed me that the potable water service door had been removed; placed in the cockpit; and entered in the cdl on a previous flight leg. The cdl has a requirement to secure the opened compartment's hinges and any other loose items before flight. He said that the door hinges were left unsecured and suggested they might have caused the vibration/noise.

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Original NASA ASRS Text

Title: Unusual sounds and vibrations in flight caused the flight crew of a B757-200 to return to their departure airport where it was determined maintenance had not secured the loose ends of the hinges for the potable water door as required by the CDL procedure for operation with the door removed.

Narrative: During climb out; the Lead Flight Attendant informed me of excessive floor vibration and loud noise in the forward galley area. I asked her to have another Flight Attendant to verify and advise me of what she heard. After their reports; I went to the forward galley and heard/felt the noise/vibration. Upon return to the cockpit and after discussion with the First Officer; I believed that the noise/vibration was increasing with the aircraft's increasing speed. I had the First Officer slow to 250 KTS and obtained ATC clearance to return to the departure airport. Our arrival gross weight exceeded the maximum landing weight; so I briefed the crew of our need to declare an emergency; briefed the flight attendants and informed the passengers. We ran the QRH Over-Weight Landing checklist and notified Dispatch. ATC was informed of our emergency status and told us CFR was standing by. I transitioned to pilot flying; landed the aircraft and; after being told the aircraft appeared normal; taxied to the gate. After gate arrival; Maintenance informed me that the potable water service door had been removed; placed in the cockpit; and entered in the CDL on a previous flight leg. The CDL has a requirement to secure the opened compartment's hinges and any other loose items before flight. He said that the door hinges were left unsecured and suggested they might have caused the vibration/noise.

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.