Narrative:

On taxi out the 'a' flight attendant called the flight deck and asked if we heard a 'siren' or 'alarm' sound. We assumed she meant an emergency vehicle outside the aircraft. We did not; but asked her to keep us informed. Just as we were taking the runway she called again. This time she was expressing concern over the sound; as were some of the passengers. She thought the sound was coming from an overhead bin. We declined taking off and cleared the runway. ATC eventually had us taxi to a vacant area to the far west of the airport. Once we arrived in the remote area the flight attendant asked the passengers in the vicinity of the sound if they could explain the sound. None could. She then had them retrieve their bags from the overhead to 'make sure.' no explanation was forthcoming; which began to raise my suspicions. To be clear: the first officer and I did not ask for assistance; nor did we at any time use the words: 'bomb'; 'security'; or 'suspicious' on the radio frequency. As we were sorting this out several police cars gathered around us and blocked our forward progress. After some discussion with the first officer and the police we decided the best course of action would be to deplane the passengers and inspect the aircraft. The aircraft was inspected by police dogs; police; and company maintenance personnel. Nothing suspicious was found. During the event I was in contact (by phone) with dispatch maintenance control and the chief pilot. There were also detectives and station managers on the scene. The detective ran a search on the passenger manifest; which did not turn up anything. After discussion with my crew we decided we wanted to continue the flight. None of our 99 passengers opted to remain behind (all continued on with us).I have not heard the official explanation but the police suspected the noise was coming from a credit card scanner in the overhead that the flight attendants use for on board purchases.

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Original NASA ASRS Text

Title: EMB190 Captain is informed by the A Flight Attendant of a siren-like noise in the cabin. The aircraft is taxied to a remote area where the passengers are deplaned and the aircraft throughly inspected by security; dogs; and company maintenance personnel. Nothing is found and the flight departs with all passengers on board.

Narrative: On taxi out the 'A' Flight Attendant called the flight deck and asked if we heard a 'siren' or 'alarm' sound. We assumed she meant an emergency vehicle outside the aircraft. We did not; but asked her to keep us informed. Just as we were taking the runway she called again. This time she was expressing concern over the sound; as were some of the passengers. She thought the sound was coming from an overhead bin. We declined taking off and cleared the runway. ATC eventually had us taxi to a vacant area to the far west of the airport. Once we arrived in the remote area the Flight Attendant asked the passengers in the vicinity of the sound if they could explain the sound. None could. She then had them retrieve their bags from the overhead to 'make sure.' No explanation was forthcoming; which began to raise my suspicions. To be clear: the First Officer and I did not ask for assistance; nor did we at any time use the words: 'bomb'; 'security'; or 'suspicious' on the radio frequency. As we were sorting this out several police cars gathered around us and blocked our forward progress. After some discussion with the First Officer and the police we decided the best course of action would be to deplane the passengers and inspect the aircraft. The aircraft was inspected by police dogs; police; and company Maintenance personnel. Nothing suspicious was found. During the event I was in contact (by phone) with Dispatch Maintenance Control and the Chief Pilot. There were also detectives and station managers on the scene. The detective ran a search on the passenger manifest; which did not turn up anything. After discussion with my crew we decided we wanted to continue the flight. None of our 99 passengers opted to remain behind (all continued on with us).I have not heard the official explanation but the police suspected the noise was coming from a credit card scanner in the overhead that the Flight Attendants use for on board purchases.

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.