Narrative:

After takeoff, cabin and cockpit crew noticed a strong burning odor in the cabin. The odor dissipated within 30 seconds without crew action. A few moments later, the cabin crew reported a hot spot on the aircraft sidewall in the vicinity of the overwing exits. The crew initiated a return to ZZZ shortly thereafter. The hot spot spread to the aircraft floor. An emergency was declared, followed by an uneventful descent and landing. After landing, a smoky haze was reported in the passenger cabin. A passenger evacuate/evacuation was initiated through the forward right door. The aircraft was secured and towed to parking. Callback conversation with reporter revealed the following information: the reporter stated the flight crew never did see the haze or smell the burning odor that was reported by the cabin crew. The reporter said the flight crew did not leave the cockpit to check the reported hot spots in the sidewall or floor. The reporter stated the airplane was removed from service and all pneumatic and air conditioning ducting was checked for broken ducting, connections and leaks. The reporter said no discrepancies were found and the airplane was test flown with no hot spots found.

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Original NASA ASRS Text

Title: A B737-800 IN CLB AT FL220 DECLARED AN EMER AND DIVERTED DUE TO CABIN CREW RPT OF SIDEWALL AND CABIN FLOOR HOT SPOTS.

Narrative: AFTER TKOF, CABIN AND COCKPIT CREW NOTICED A STRONG BURNING ODOR IN THE CABIN. THE ODOR DISSIPATED WITHIN 30 SECONDS WITHOUT CREW ACTION. A FEW MOMENTS LATER, THE CABIN CREW RPTED A HOT SPOT ON THE ACFT SIDEWALL IN THE VICINITY OF THE OVERWING EXITS. THE CREW INITIATED A RETURN TO ZZZ SHORTLY THEREAFTER. THE HOT SPOT SPREAD TO THE ACFT FLOOR. AN EMER WAS DECLARED, FOLLOWED BY AN UNEVENTFUL DSCNT AND LNDG. AFTER LNDG, A SMOKY HAZE WAS RPTED IN THE PAX CABIN. A PAX EVAC WAS INITIATED THROUGH THE FORWARD R DOOR. THE ACFT WAS SECURED AND TOWED TO PARKING. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE FLC NEVER DID SEE THE HAZE OR SMELL THE BURNING ODOR THAT WAS RPTED BY THE CABIN CREW. THE RPTR SAID THE FLC DID NOT LEAVE THE COCKPIT TO CHK THE RPTED HOT SPOTS IN THE SIDEWALL OR FLOOR. THE RPTR STATED THE AIRPLANE WAS REMOVED FROM SVC AND ALL PNEUMATIC AND AIR CONDITIONING DUCTING WAS CHKED FOR BROKEN DUCTING, CONNECTIONS AND LEAKS. THE RPTR SAID NO DISCREPANCIES WERE FOUND AND THE AIRPLANE WAS TEST FLOWN WITH NO HOT SPOTS FOUND.

Data retrieved from NASA's ASRS site as of July 2007 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.