Narrative:

After takeoff we heard a banging noise coming from the outside of the aircraft. It sounded like an unbalanced washing machine. As speed increased; the noise increased. While talking over the noise with the #1 flight attendant she stated that the noise was coming from the top left corner of the forward passenger entry door as seen from the inside of the aircraft. You could hear the noise back to seat row 6. I decided to return and have the aircraft checked by maintenance. We declared an emergency and returned for an over weight landing without incident. When we arrived at the gate we waited for maintenance to inspect the door before it was opened. He found an orange strap about 2 feet in length hung up in the door at the location where we heard the noise coming from. There was some damage to the inside seal of the door from the strap. The aircraft was taken out of service. A new aircraft was assigned and we continued with the flight.

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Original NASA ASRS Text

Title: Air Carrier Captain reports a loud banging noise coming outside the main entry door after takeoff and during climb. The crew elected to return for a Maintenance inspection where an orange strap was found extending from the door seal.

Narrative: After takeoff we heard a banging noise coming from the outside of the aircraft. It sounded like an unbalanced washing machine. As speed increased; the noise increased. While talking over the noise with the #1 Flight Attendant she stated that the noise was coming from the top left corner of the forward passenger entry door as seen from the inside of the aircraft. You could hear the noise back to seat row 6. I decided to return and have the aircraft checked by Maintenance. We declared an emergency and returned for an over weight landing without incident. When we arrived at the gate we waited for Maintenance to inspect the door before it was opened. He found an orange strap about 2 feet in length hung up in the door at the location where we heard the noise coming from. There was some damage to the inside seal of the door from the strap. The aircraft was taken out of service. A new aircraft was assigned and we continued with the flight.

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.