Narrative:

About 1 hour 10 mins after departure, second flight attendant rang up and informed me that 'numerous passenger' in rows 15-18 'especially on the right side' commented about 'a burning smell' and one of them 'says he is a pilot.' flight deck immediately donned crew oxygen masks and captain ordered u-turn to abq and requested return to abq and lower altitude from center. Captain then called first flight attendant (most experienced) and told him to go investigate and report back. In a couple of mins, first flight attendant reported no smell, no smoke, no fire and then second flight attendant agreed there were no smells. Flight attendants suggested passenger may have smelled burned food from ovens or captain suspected (the good old) compressor wash (dirty socks) smell. Flight returned to original flight plan to bwi and no emergency declared up till then. Almost immediately (within 4 O5 5 mins) 'burning smell' returned. First officer dispatched to evaluate situation, returned and said he couldn't smell it, but he (the captain) would go evaluate. I went back and was unable to smell anything either. However, all passenger in cabin were adamant and obviously concerned. Additionally, the pilot turned out to be an air force pilot. He knew the difference in the 'burning socks' and real stuff. His statement to me that it was 'an acrid burning smell' convinced me to divert to abq. After briefing flight attendants, contacting dispatch, flight operations management and then the dispatcher agreed with the diversion, abq was notified and an emergency was then declared. An overweight landing was made without incident. Source of smell later tracked to 3 cabin lighting ballasts on the left side of aircraft.

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Original NASA ASRS Text

Title: A320 CREW WAS INFORMED OF A BURNING ODOR IN THE CABIN IN ZAB CLASS A AIRSPACE.

Narrative: ABOUT 1 HR 10 MINS AFTER DEP, SECOND FLT ATTENDANT RANG UP AND INFORMED ME THAT 'NUMEROUS PAX' IN ROWS 15-18 'ESPECIALLY ON THE R SIDE' COMMENTED ABOUT 'A BURNING SMELL' AND ONE OF THEM 'SAYS HE IS A PLT.' FLT DECK IMMEDIATELY DONNED CREW OXYGEN MASKS AND CAPT ORDERED U-TURN TO ABQ AND REQUESTED RETURN TO ABQ AND LOWER ALT FROM CTR. CAPT THEN CALLED FIRST FLT ATTENDANT (MOST EXPERIENCED) AND TOLD HIM TO GO INVESTIGATE AND RPT BACK. IN A COUPLE OF MINS, FIRST FLT ATTENDANT RPTED NO SMELL, NO SMOKE, NO FIRE AND THEN SECOND FLT ATTENDANT AGREED THERE WERE NO SMELLS. FLT ATTENDANTS SUGGESTED PAX MAY HAVE SMELLED BURNED FOOD FROM OVENS OR CAPT SUSPECTED (THE GOOD OLD) COMPRESSOR WASH (DIRTY SOCKS) SMELL. FLT RETURNED TO ORIGINAL FLT PLAN TO BWI AND NO EMER DECLARED UP TILL THEN. ALMOST IMMEDIATELY (WITHIN 4 O5 5 MINS) 'BURNING SMELL' RETURNED. FO DISPATCHED TO EVALUATE SIT, RETURNED AND SAID HE COULDN'T SMELL IT, BUT HE (THE CAPT) WOULD GO EVALUATE. I WENT BACK AND WAS UNABLE TO SMELL ANYTHING EITHER. HOWEVER, ALL PAX IN CABIN WERE ADAMANT AND OBVIOUSLY CONCERNED. ADDITIONALLY, THE PLT TURNED OUT TO BE AN AIR FORCE PLT. HE KNEW THE DIFFERENCE IN THE 'BURNING SOCKS' AND REAL STUFF. HIS STATEMENT TO ME THAT IT WAS 'AN ACRID BURNING SMELL' CONVINCED ME TO DIVERT TO ABQ. AFTER BRIEFING FLT ATTENDANTS, CONTACTING DISPATCH, FLT OPS MGMNT AND THEN THE DISPATCHER AGREED WITH THE DIVERSION, ABQ WAS NOTIFIED AND AN EMER WAS THEN DECLARED. AN OVERWT LNDG WAS MADE WITHOUT INCIDENT. SOURCE OF SMELL LATER TRACKED TO 3 CABIN LIGHTING BALLASTS ON THE L SIDE OF ACFT.

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.