Narrative:

During taxi for takeoff with both air conditioning packs operating in automatic mode, I noticed a 'hot air conditioning' smell. I alerted the flight attendant and we were immediately faced within rapid succession, a duct overheat, pack trip offirst officerverheat and smoke throughout the aircraft. Pandemonium ensued as people, mostly children, began screaming and moving into the aisle. 3 of our 4 flight attendants were, fortunately, very experienced, and recognized the source of the smoke/smell as air conditioning. Their quick reaction was instrumental in calming passenger who were rapidly reaching panic mode. I picked up the PA microphone and urged people to remain seated, but in some sections of the cabin, my repeated PA's were drowned out by screaming kids. The flight attendants' immediate presence in the aisle most likely prevented an uncommanded, uncontrolled evacuate/evacuation on the taxiway. A return to the gate for maintenance action revealed the cause of the pack overheat to be an inoperative cooling fan door, and we were subsequently dispatched with that air conditioning pack inoperative on the ground. It's interesting to note that our relatively new flight attendant, who did not immediately recognize the source of the smoke, did immediately produce a fire extinguisher, until she was advised by her co-worker of the actual source. Also, once people understood the actual problem, they were very cooperative and very understanding. Effective, immediate flight crew communication in the early moments of this incident prevented a panic situation in the cabin.

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Original NASA ASRS Text

Title: ON A B727, SUDDEN SMOKE FILLED THE CABIN WHILE ON THE TXWY IN SLC, RESULTING IN RETURN TO GATE FOR MAINT ACTION.

Narrative: DURING TAXI FOR TKOF WITH BOTH AIR CONDITIONING PACKS OPERATING IN AUTO MODE, I NOTICED A 'HOT AIR CONDITIONING' SMELL. I ALERTED THE FLT ATTENDANT AND WE WERE IMMEDIATELY FACED WITHIN RAPID SUCCESSION, A DUCT OVERHEAT, PACK TRIP OFF/OVERHEAT AND SMOKE THROUGHOUT THE ACFT. PANDEMONIUM ENSUED AS PEOPLE, MOSTLY CHILDREN, BEGAN SCREAMING AND MOVING INTO THE AISLE. 3 OF OUR 4 FLT ATTENDANTS WERE, FORTUNATELY, VERY EXPERIENCED, AND RECOGNIZED THE SOURCE OF THE SMOKE/SMELL AS AIR CONDITIONING. THEIR QUICK REACTION WAS INSTRUMENTAL IN CALMING PAX WHO WERE RAPIDLY REACHING PANIC MODE. I PICKED UP THE PA MIKE AND URGED PEOPLE TO REMAIN SEATED, BUT IN SOME SECTIONS OF THE CABIN, MY REPEATED PA'S WERE DROWNED OUT BY SCREAMING KIDS. THE FLT ATTENDANTS' IMMEDIATE PRESENCE IN THE AISLE MOST LIKELY PREVENTED AN UNCOMMANDED, UNCTLED EVAC ON THE TXWY. A RETURN TO THE GATE FOR MAINT ACTION REVEALED THE CAUSE OF THE PACK OVERHEAT TO BE AN INOP COOLING FAN DOOR, AND WE WERE SUBSEQUENTLY DISPATCHED WITH THAT AIR CONDITIONING PACK INOP ON THE GND. IT'S INTERESTING TO NOTE THAT OUR RELATIVELY NEW FLT ATTENDANT, WHO DID NOT IMMEDIATELY RECOGNIZE THE SOURCE OF THE SMOKE, DID IMMEDIATELY PRODUCE A FIRE EXTINGUISHER, UNTIL SHE WAS ADVISED BY HER CO-WORKER OF THE ACTUAL SOURCE. ALSO, ONCE PEOPLE UNDERSTOOD THE ACTUAL PROB, THEY WERE VERY COOPERATIVE AND VERY UNDERSTANDING. EFFECTIVE, IMMEDIATE FLC COM IN THE EARLY MOMENTS OF THIS INCIDENT PREVENTED A PANIC SIT IN THE CABIN.

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.