Narrative:

Approximately 25 minutes prior to pushback with the aircraft boarding mostly complete; the purser came to the flight deck to notify me of a burning electrical smell coming from the mid cabin area. I left the flight deck to investigate and did smell a faint electrical burning smell in the vicinity of row 30. I attempted to locate the source of the smell but was unable. I told the first officer to turn on the APU and have the pc air disconnected in the hopes the fumes were coming from outside the aircraft. After 5 minutes on APU air and the smell still present I contacted [maintenance] who responded very quickly; probably within 5 minutes. A separate 'fumes' team handed me a fumes/odor report which I filled out on the flight deck while they attempted to locate the source of smell. Shortly after completing the form I called to the aft flight attendant station in an attempt to ascertain whether the smell was present prior to boarding. My thinking was perhaps a passenger's personal electronic device was the source. In mid conversation the flight attendant advised me that another flight attendant working in the back of the aircraft had grabbed a fire extinguisher and returned to the row 30 area. I immediately left the flight deck and proceeded to the entry door; 2L. A customer service agent was making an announcement for all passengers to take their personal belongings and leave the aircraft I believe at the direction of the [maintenance] team.one of the technicians approached and advised me that a passenger had observed smoke and flames coming from a light above an overhead bin on the left side of the aircraft. I did not see any smoke or flames. I immediately made an additional announcement to the passengers explaining the need for expeditious deplaning. The flight attendant who retrieved the fire extinguisher had immediately moved the passengers from the 4-5 rows around the source of the smoke/flames to the front of the aircraft near the exit door. All passengers were deplaned within 10 minutes. I proceeded to the row 30 area were the technicians were already investigating a florescent light socket that was the source of the problem. I did not observe any flames; smoke or fumes. I did see a small area of scorch marks on the trim above the socket. [Maintenance] removed the socket and secured the wires per MEL. The aircraft was re-boarded and we proceeded to our destination without further incident.

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Original NASA ASRS Text

Title: B757 flight crew reported a passenger advised a flight attendant that smoke and flames were coming from a cabin light fixture.

Narrative: Approximately 25 minutes prior to pushback with the aircraft boarding mostly complete; the Purser came to the flight deck to notify me of a burning electrical smell coming from the mid cabin area. I left the flight deck to investigate and did smell a faint electrical burning smell in the vicinity of row 30. I attempted to locate the source of the smell but was unable. I told the First Officer to turn on the APU and have the PC air disconnected in the hopes the fumes were coming from outside the aircraft. After 5 minutes on APU air and the smell still present I contacted [Maintenance] who responded very quickly; probably within 5 minutes. A separate 'fumes' team handed me a fumes/odor report which I filled out on the flight deck while they attempted to locate the source of smell. Shortly after completing the form I called to the aft flight attendant station in an attempt to ascertain whether the smell was present prior to boarding. My thinking was perhaps a passenger's personal electronic device was the source. In mid conversation the flight attendant advised me that another flight attendant working in the back of the aircraft had grabbed a fire extinguisher and returned to the row 30 area. I immediately left the flight deck and proceeded to the entry door; 2L. A customer service agent was making an announcement for all passengers to take their personal belongings and leave the aircraft I believe at the direction of the [Maintenance] team.One of the technicians approached and advised me that a passenger had observed smoke and flames coming from a light above an overhead bin on the left side of the aircraft. I did not see any smoke or flames. I immediately made an additional announcement to the passengers explaining the need for expeditious deplaning. The flight attendant who retrieved the fire extinguisher had immediately moved the passengers from the 4-5 rows around the source of the smoke/flames to the front of the aircraft near the exit door. All passengers were deplaned within 10 minutes. I proceeded to the row 30 area were the technicians were already investigating a florescent light socket that was the source of the problem. I did not observe any flames; smoke or fumes. I did see a small area of scorch marks on the trim above the socket. [Maintenance] removed the socket and secured the wires per MEL. The aircraft was re-boarded and we proceeded to our destination without further incident.

Data retrieved from NASA's ASRS site 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.