B777 Undifferentiated or Other Model
Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine; Flight Crew Instrument
Flight Crew Last 90 Days 196.35; Flight Crew Total 22099.55; Flight Crew Type 7756.68
Situational Awareness
Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor
Air Traffic Control Provided Assistance; Flight Crew Landed As Precaution; Flight Crew Overcame Equipment Problem; Flight Crew Returned To Departure Airport; General Maintenance Action
Aircraft
Flight attendants reported electrical smell in aft galley after takeoff. [Relief Pilot] was sent to investigate. He determined that it was not electrical. All ovens and galley equipment were verified to be operating normally. [Maintenance Control] and Dispatch were conferenced. There was no EICAS messages. [Maintenance Control] did not have any abnormal telemetry data. Dispatch agreed that a precautionary Maintenance return was in order. The smell never intensified or went away. Fuel was dumped; all normal checklists were run. We did not declare an emergency; we did not land overweight.
Unidentifiable odor in aft galley at takeoff. Odor remained for entire flight. Source of odor could not be identified. Odor neither diminished nor intensified. The cabin crew was uncomfortable continuing; and passengers were also aware of the odor. The decision to return to ZZZ as a maintenance issue. There were no abnormal system indications on the flight deck. We contacted [Maintenance Control] to discuss maintenance history and to verify that he had no abnormal system indications. We did not declare an emergency. We dumped fuel as to arrive at ZZZ at max landing weight.
B777 flight crew reported precautionary air return due to persistent odor throughout the aircraft.