An A300 flight crew declared an emergency and returned to their departure airport after receipt of a...

Attributes
ACN	1074958
Time
Date	201303
Local Time Of Day	0001-0600
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Make Model Name	A300
Operating Under FAR Part	Part 121
Flight Phase	Climb
Flight Plan	IFR
Component
Aircraft Component	Circuit Breaker / Fuse / Thermocouple
Person 1
Function	First Officer Pilot Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Events
Anomaly	Aircraft Equipment Problem Critical Deviation - Procedural Maintenance Deviation - Procedural Published Material / Policy Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor

Narrative:

During our enroute climb we received an avionics smoke warning accompanied by the smell of fumes. We declared an emergency and got vectors to return to our departure airport. After landing we stopped on the runway for crash fire rescue equipment to inspect for hot spots. When they found none we cleared runway and taxied to ramp parking where crash fire rescue equipment inspected inside the aircraft for overheating avionics and/or lithium batteries in a shipping container. Preceding this event we had a deferral of the field limit computer system 2 and the MEL did not direct us to pull the circuit breakers; thus power was applied to [the system which] caused overheating and fumes of the system 2 computer. I recommend that pulling circuit breakers should be written into the MEL.

Original NASA ASRS Text

Title: An A300 flight crew declared an emergency and returned to their departure airport after receipt of an Avionics Smoke warning accompanied by the smell of electrical fumes. A circuit breaker involved with an associated system had not been pulled when deferred prior to departure.

Narrative: During our enroute climb we received an Avionics Smoke Warning accompanied by the smell of fumes. We declared an emergency and got vectors to return to our departure airport. After landing we stopped on the runway for CFR to inspect for hot spots. When they found none we cleared runway and taxied to ramp parking where CFR inspected inside the aircraft for overheating avionics and/or lithium batteries in a shipping container. Preceding this event we had a deferral of the Field Limit Computer System 2 and the MEL did not direct us to pull the circuit breakers; thus power was applied to [the system which] caused overheating and fumes of the system 2 computer. I recommend that pulling circuit breakers should be written into the MEL.

Data retrieved from NASA's ASRS site as of July 2013 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.

An A300 flight crew declared an emergency and returned to their departure airport after receipt of an avionics smoke warning accompanied by the smell of electrical fumes. A circuit breaker involved with an associated system had not been pulled when deferred prior to departure.