Narrative:

Shortly after takeoff; the flight attendants called the flight deck and reported that passengers were yelling that there was a fire on the left side of the aircraft. We had not yet reached our 1000 feet clean up altitude and were just beginning a turn to the west on the departure. We had no fire/overheat indications on the flight deck and all engine readings were normal. However; the intensity and concern in the flight attendants' report was evident; and we elected to [advise ATC] and continue our turn onto a left downwind for a return to the runway. We immediately informed the fas of the plan to return and; given the lack of abnormal indications on the flight deck; informed them that we did not anticipate an evacuation. I flew a normal and uneventful visual approach and exited. Crash fire rescue immediately informed us that there was no visual indication of any fire or smoke. We verified this with crash fire rescue and then elected to do a normal shut down of the number one engine as a precaution. The flight attendants were then contacted and informed that we still did not have any fire indications on the flight deck and that crash fire rescue did not see any indications of fire or smoke. We asked the fas again if they saw any visual indication of fire or smoke and they confirmed that there was not. At that point we elected to return to the gate.

Related reports:

Google
 

Original NASA ASRS Text

Title: After takeoff; some B737-700 passengers claimed the number 1 engine was on fire; so as a precaution the crew returned to the departure airport. No fire or overheat warnings alerted during flight.

Narrative: Shortly after takeoff; the Flight Attendants called the flight deck and reported that Passengers were yelling that there was a fire on the left side of the aircraft. We had not yet reached our 1000 feet clean up altitude and were just beginning a turn to the west on the departure. We had no fire/overheat indications on the flight deck and all engine readings were normal. However; the intensity and concern in the Flight Attendants' report was evident; and we elected to [advise ATC] and continue our turn onto a left downwind for a return to the runway. We immediately informed the FAs of the plan to return and; given the lack of abnormal indications on the flight deck; informed them that we did not anticipate an evacuation. I flew a normal and uneventful visual approach and exited. Crash Fire Rescue immediately informed us that there was no visual indication of any fire or smoke. We verified this with Crash Fire Rescue and then elected to do a normal shut down of the number one engine as a precaution. The Flight Attendants were then contacted and informed that we still did not have any fire indications on the flight deck and that Crash Fire Rescue did not see any indications of fire or smoke. We asked the FAs again if they saw any visual indication of fire or smoke and they confirmed that there was not. At that point we elected to return to the gate.

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.