B777 flight crew reported air return shortly after takeoff due to fumes in the cabin.

Attributes
ACN	1605295
Time
Date	201812
Local Time Of Day	1801-2400
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	VMC
Aircraft 1
Make Model Name	B777 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	Climb Initial Climb
Flight Plan	IFR
Component
Aircraft Component	Air Conditioning and Pressurization Pack
Person 1
Function	Pilot Flying Captain
Qualification	Flight Crew Multiengine Flight Crew Air Transport Pilot (ATP) Flight Crew Instrument
Experience	Flight Crew Last 90 Days 170 Flight Crew Total 8930 Flight Crew Type 1363
Person 2
Function	Pilot Not Flying First Officer
Qualification	Flight Crew Air Transport Pilot (ATP) Flight Crew Instrument Flight Crew Multiengine
Experience	Flight Crew Last 90 Days 197 Flight Crew Total 6121 Flight Crew Type 1278
Events
Anomaly	Aircraft Equipment Problem Less Severe Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor

Narrative:

Shortly after takeoff received a call from cabin stating that they were experiencing smoke and fumes in the cabin primarily by door 3 left. Continued with the after takeoff profile and checklist; continued climb to above 10;000 feet. Received a second call from the cabin regarding the smoke and fumes; and sent one of the relief pilots to the cabin to assess the situation. As the cockpit door opened and closed we immediately smelled the fumes coming from the cabin. Shortly thereafter; the relief pilot called to report a fireworks-like smell in the cabin; no smoke but plenty of fumes. At that point we elected to return to ZZZ; [notified ATC;] and commenced fuel dump. Approach offered us an immediate return to rwy xxr; but I declined since we did not have smoke and the situation did not seem to be escalating. We dumped fuel as we flew the downwind for rwy xyl. We made a satcom call to dispatch and requested landing data be uplinked for rwy xyl at our projected landing weight after fuel dumping. We experienced several status messages; and a pack overheat as we turned final. We turned the pack off and continued the approach to a normal landing; taxi in and parking. Excellent CRM and coordination with ATC and dispatch made this a successful and safe return to field.

Original NASA ASRS Text

Title: B777 flight crew reported air return shortly after takeoff due to fumes in the cabin.

Narrative: Shortly after takeoff received a call from cabin stating that they were experiencing smoke and fumes in the cabin primarily by door 3 left. Continued with the after takeoff profile and checklist; continued climb to above 10;000 feet. Received a second call from the cabin regarding the smoke and fumes; and sent one of the relief pilots to the cabin to assess the situation. As the cockpit door opened and closed we immediately smelled the fumes coming from the cabin. Shortly thereafter; the relief pilot called to report a fireworks-like smell in the cabin; no smoke but plenty of fumes. At that point we elected to return to ZZZ; [notified ATC;] and commenced fuel dump. Approach offered us an immediate return to Rwy XXR; but I declined since we did not have smoke and the situation did not seem to be escalating. We dumped fuel as we flew the downwind for rwy XYL. We made a SATCOM call to dispatch and requested landing data be uplinked for rwy XYL at our projected landing weight after fuel dumping. We experienced several status messages; and a pack overheat as we turned final. We turned the pack off and continued the approach to a normal landing; taxi in and parking. Excellent CRM and coordination with ATC and dispatch made this a successful and safe return to field.

Data retrieved from NASA's ASRS site 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.