Date: 201603
Local time of day: 0601-1200
Location: ZZZ.Airport, US
Flight conditions: VMC
Light: Daylight
Aircraft: Large Transport
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Climb
Airspace: Class B ZZZ
ATC / advisory: TRACON ZZZ
Aircraft component: Cargo Compartment Fire/Overheat Warning
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: Captain
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Anomaly: Aircraft Equipment Problem Critical; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor; Flight Deck / Cabin / Aircraft Event Illness / Injury
Detector: Person Flight Attendant; Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Provided Assistance; Flight Crew Overcame Equipment Problem; Flight Crew Returned To Departure Airport; Flight Crew Landed in Emergency Condition
Contributing factors: Aircraft
Primary problem: Aircraft

Narrative: After a lengthy one step de-icing we then taxied to the runway. Upon being cleared to depart I performed a static; Takeoff Go-Around [powered] takeoff without incident. At thrust reduction altitude I reduced power and the First Officer (FO) set Pack 1 to on. Almost immediately we received a call from the aft Flight Attendant (FA).As the Pilot Monitoring; the FO answered the call and after I overheard his initial questions and responses I selected my ACP CABIN button to on so I could listen in. They told us that there was a lot of 'fog' coming into the aft galley; grey like smoke. While she was still on the line we reached flap retraction speed and I commanded flaps up from the FO. He raised the flaps and set Pack 2 to on. The Flight Attendant immediately said; 'Now smoke is pouring into the cabin and people are very concerned.' Hearing this I transferred control and radios to the FO; advised him to level off as soon as allowable; advised ATC of our situation and request an immediate return to the airport. He did all of the above. At this point we began to receive a moderate influx of smoke into the flight deck. The smoke seemed to be emanating from both the vents on the glare shield and from beneath our feet. I told the FO and our observer in the jump seat to don their masks. Nearly simultaneously to transferring controls we received a SMOKE: AFT LAV ECAM and associated Master Warning. I verbalized this to the cabin and within seconds received SMOKE: AFT CARGO Master Warning which I also verbalized to the FA's and asked them to stand by.I followed the above ECAM's completely to include discharge of AGENT into the AFT CARGO pit. After completing the ECAM procedure I reconnected with the FA's. We talked through the [emergency checklist] and I verified that everyone was clear on the plan; they replied affirmatively. I asked them to inspect the floor in the aft galley and cabin to check for heat. The FA reported back that they had done that and the floor was definitely not hot and the smoke seemed to have stopped entering the cabin.While back and forth between ECAM and communicating with the FA's I handed the observer our QRH and told him to open the red tab; find the smoke checklists for both lav and cargo; back us up and point out anything he thought was important or we were missing. At this point I made a PA to advise the passengers that due to the obvious smoke situation we were making an immediate return to the airport; that I felt strongly that we did not have a fire on board and that the smoke was possibly from a large ingestion of de-icing fluid; but to be safe we would return. I further advised them to expect to see a lot of fire equipment surrounding the airplane upon exiting the runway. I checked back with the FO and he briefed me that we had been cleared for a visual approach. At this point we were probably on a 7 or 8 mile left base. I consulted the observer on his thoughts and he said he had reviewed the QRH and had nothing to add and felt like we had not missed anything. At this point I contacted approach and advised them that our procedure called for disembarking passengers prior to accessing the cargo pit and requested that he pass that on to Airport Rescue and Fire Fighting (ARFF). I advised him that I planned on exiting the runway; but did not want to evacuate onto an icy taxiway unless absolutely necessary and asked if we could expedite air stairs. He advised that that would occur and added that busses would be immediately dispatched as well. After collaborating logistics with approach I contacted OPS. I quickly advised them of our emergency return and asked that they help with coordinating logistics.I made a second PA advising passengers of our plan to exit the aircraft on the taxiway via air stairs into busses. I stressed to them that I needed their cooperation in a calm; orderly and safe 'normal' exit; but to be prepared for a different command if the situation changed. By now theFO had done an impeccable 'single pilot' job of: changing our destination; programming the FMS; flying and configuring the aircraft and by the time I rejoined him; now as PM; we were fully configured and stabilized for landing.I switched to tower; confirmed clearance to land and reiterated our request to ARFF to disembark passengers prior to opening the aft pit. I brought him up to speed on all my plans and coordination. I advised him that I did not intend to take control of the aircraft after landing and that I wanted him to taxi off so I was best available to continue coordinating and communicating to emergency personnel. We conducted a normal; uneventful landing. Once it was clear that we would easily make the first high-speed taxiway; but to hold short so we could keep things fully clear for use. As we came to a stop I gave a 'Remain seated' PA. Tower advised us to switch to ground frequency OPS command. Prior to connecting with ARFF I spoke with the FA's and confirmed with them that air stairs were coming to the airplane and would come up to doors 1L and 2L. They asked if they should disarm doors and I stated; yes. I gave a 'Doors verified' PA and we ran a parking checklist. We were contacted by OPS command. They told us that ARFF was conducting a 360 inspection and once cleared they would bring air stairs to the airplane. He asked if anyone needed immediate medical attention and after confirmation with the cabin crew I told him not at this time. I inquired about busses and he said they were on the taxiway behind the aircraft. ARFF confirmed that there was no external indication of fire or smoke and they were bringing air stairs to the aircraft. After door 1L was opened I met with the Fire Lieutenant (LT) in command; received his report and plan for getting the folks safely onto the busses and continued to do all my coordination face to face with him. While ARFF brought air stairs to both exits they chose to only exit passengers through door 1L in order to maintain a more coordinated control of people directly onto the busses. We made a series of PA's advising passengers of our plan to take 10 at a time down the stairs and onto the busses. We advised everyone that Paramedics were waiting at the bottom of the stairs and to let them know if they needed medical evaluation.ARFF made a final sweep of the aircraft interior and exterior and we coordinated a clearing of all their equipment. They advised their equipment was clear; we were clear to start our engines and to advise ground when we were ready to taxi. We received taxi clearance. Unfortunately; upon entering the ramp we had to wait approximately 15+ minutes for an aircraft to push back and clear. This forced both ARFF and OPS to wait as well as they were trailing us to the gate. I confirmed with Ops that they knew we were the Air Turn Back aircraft and that we and ARFF were waiting out here on the ramp. They said they were aware. We got parked and were met by a line mechanic and MX Supervisor. I gave them a firsthand report and let them know what write ups I had placed in the logbook. An ACP also met us at the plane.




Synopsis: During climb while turning air conditioning packs on smoke began to fill the cabin and cockpit. The crew elected to return to the point of departure. Passengers were deplaned normally.