Date: 201402
Location: ZZZ.Airport, US
Aircraft: B737 Undifferentiated or Other Model
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Takeoff / Launch
ATC / advisory: Tower ZZZ
Aircraft component: Air Conditioning and Pressurization Pack
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Not Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Second reporter function: First Officer; Pilot Flying
Anomaly: Aircraft Equipment Problem Critical; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor
Detector: Person Flight Attendant
When detected: In-flight
Result: Flight Crew Landed in Emergency Condition; Flight Crew Returned To Departure Airport; Flight Crew Overcame Equipment Problem; General Maintenance Action; General Declared Emergency
Contributing factors: Aircraft
Primary problem: Aircraft

Narrative: During taxi for departure we had the right pack light illuminate. We consulted the QRH and MEL; performed the QRH procedure; and the PACK light extinguished. Takeoff roll was normal. As I was about to bring the gear up we both heard the flight attendant chime sound twice. I picked up the interphone and was told there was smoke in the cabin. I told the flight attendants that we were returning immediately. I advised ATC that we were declaring an emergency and had smoke in the cabin. I also advised ATC there could be no delay getting us to the runway. The First Officer and I agreed that shutting off the right PACK switch as a precaution was a prudent measure considering what had occurred on taxi-out. We ran all Normal Checklist items prior to landing. Total flight time was 7 minutes. We taxied off the runway and came to a complete stop and asked the flight attendants what the situation in the cabin was. We were told that the smoke was mainly in the aft cabin behind the over wing exits and it dissipated just before we landed. Flight attendants described the odor as both electrical and deice fluid in nature. I asked if the cabin was secure and told them that we were going to taxi to an area to discuss our situation with the Aircraft Rescue and Fire Fighters (ARFF). They performed a thermal imaging scan of the aircraft prior to us taxing to gate. Appropriate PAs were made to the passengers during flight and upon landing. At the gate we wrote up the right pack and the smoke in the cabin. The Duty Manager was contacted and advised of our situation. Maintenance met the aircraft and we briefed them on the situation as well as filled out a Maintenance questionnaire. The CPO was contacted. I used my Captain's Emergency Authority through the entire event. Captain was the pilot not flying. The First Officer was the pilot flying.


Second narrative: We arrived at the aircraft and performed our preflight duties as normal. As we taxied out towards the runway the right PACK caution light came on. We reset the pack per the QRH and everything seemed to operate normally. As it was a cold morning and this is a common occurrence; we thought nothing of it. Finally after a bit of a lineup; it was our turn for departure. I was the pilot flying; and the takeoff roll was normal. Just after liftoff as the Captain brought the gear up; we heard a call from the flight attendants. We ignored the call at first to do our after takeoff duties and concentrate on flying our LNAV departure. A few seconds later they called again; and the Captain answered. He immediately announced that we had smoke in the cabin and were returning to land. I was delegated to continue flying. He declared an emergency and told the Controller we had smoke in cabin and needed an immediate return for landing. As this was happening; I was thinking to myself what could possibly cause smoke. I remembered one captain I flew with telling me about his experience with smoke so bad in the cockpit after liftoff that they couldn't even see the instruments. This Captain told me that as soon as the packs were off the smoke began to clear. After consulting with my Captain and jointly determining that under his emergency authority and due to not needing it for our short flight; we decided to turn off the right pack that had tripped on the ground. I don't know if that did any good or not but the attendants told us that by the time we turned out to the east the smoke began to clear. The Captain ran all the normal checklists as I decelerated and maneuvered for an approach. As we turned final; we took a deep breath and made sure we had accomplished everything prior to landing and were comfortable to continue the approach. We landed uneventfully and taxied clear of the runway. As soon as we stopped we spoke with the flight attendants who told us everything was normal and no signs of smoke in the back. The ARFF vehicles were in touch with the captain and told us they found no hot spots and we were free to continue taxiing. We taxied back to gate and unloaded our passengers. The whole flight lasted just 7 minutes.


Synopsis: B737 flight crew is informed by a Flight Attendant just after takeoff of smoke in the cabin. A pack trip had occurred just prior to takeoff and the crew elects to turn this pack off without reference to the QRH. Flight returns to the departure airport and the smoke cleared prior to landing.