Narrative:

ATC facility: ZFW. Location: abi. During final phase of climb to FL350, flight attendant reported unfamiliar smell in aft lavatories. I determined acrid smell was overheated wiring. No smoke. No fire. First officer popped circuit breaker. Declared emergency and, as a precaution, returned to dfw. Passenger deplaned via jetbridge. Callback conversation with reporter revealed the following information: the captain is an a&P mechanic as well, so he was very familiar with the odor, identing it as electrical. That simply enforced his decision to return to dfw. Appropriate circuit breakers were pulled to isolate the suspected region. He has made a habit of briefing the flight attendants and advising them not to be shy about being suspicious about odors or anything unusual and to report those facts to the cockpit. It seems to have paid off in this incident. When at the gate the maintenance personnel went to the rear of the aircraft where the voice recorder is kept in the overhead panel. They remarked that something was 'very hot and semi scorched.' it was not a pneumatic problem. The crew was given a spare aircraft to continue their flight to lax.

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Original NASA ASRS Text

Title: A B757-200 RETURNS AND LANDS AT DFW AFTER THERE IS A FLT ATTENDANT RPT OF AN ACRID ELECTRICAL ODOR IN THE REAR OF THE ACFT OVER ABI, TX.

Narrative: ATC FACILITY: ZFW. LOCATION: ABI. DURING FINAL PHASE OF CLB TO FL350, FLT ATTENDANT RPTED UNFAMILIAR SMELL IN AFT LAVATORIES. I DETERMINED ACRID SMELL WAS OVERHEATED WIRING. NO SMOKE. NO FIRE. FO POPPED CIRCUIT BREAKER. DECLARED EMER AND, AS A PRECAUTION, RETURNED TO DFW. PAX DEPLANED VIA JETBRIDGE. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE CAPT IS AN A&P MECH AS WELL, SO HE WAS VERY FAMILIAR WITH THE ODOR, IDENTING IT AS ELECTRICAL. THAT SIMPLY ENFORCED HIS DECISION TO RETURN TO DFW. APPROPRIATE CIRCUIT BREAKERS WERE PULLED TO ISOLATE THE SUSPECTED REGION. HE HAS MADE A HABIT OF BRIEFING THE FLT ATTENDANTS AND ADVISING THEM NOT TO BE SHY ABOUT BEING SUSPICIOUS ABOUT ODORS OR ANYTHING UNUSUAL AND TO RPT THOSE FACTS TO THE COCKPIT. IT SEEMS TO HAVE PAID OFF IN THIS INCIDENT. WHEN AT THE GATE THE MAINT PERSONNEL WENT TO THE REAR OF THE ACFT WHERE THE VOICE RECORDER IS KEPT IN THE OVERHEAD PANEL. THEY REMARKED THAT SOMETHING WAS 'VERY HOT AND SEMI SCORCHED.' IT WAS NOT A PNEUMATIC PROB. THE CREW WAS GIVEN A SPARE ACFT TO CONTINUE THEIR FLT TO LAX.

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.