Narrative:

After takeoff and climbing through 3000ft; purser called to the cockpit warning us that there was a thick layer of light-gray smoke in the mid-aft passenger cabin and a strong hydraulic-like odor (apparently it started when selecting landing gear up); which caused dizziness; sore throat and eye burn to many crewmembers and a few passengers. Both pilots immediately donned the oxygen masks as a precaution should smoke enter the cockpit.'immediate actions' from the 'smoke/fumes/avionics smoke' QRH procedure were performed; which led to total smoke dissipation in only a minute. While the situation was under control and cabin crew confirmed no more smoke coming out (but still a strong; harmful odor/fumes); since it was a red-eye flight with few available airports for a further diversion and since smoke source was not immediately obvious (cabin crew could not determine where it was coming from) flight crew decided not to declare an emergency but to declare 'pan-pan' urgency to return to [departure airport] for landing. Landing was performed safely on [the] runway; and the aircraft was stopped short of runway to verify once again with cabin crew if there had been any more smoke or if an emergency evacuation would be required; while emergency equipment stood at the other side of runway. After confirming everything was still under control and smoke didn't come back we advised ATC and were cleared to taxi to gate as emergency equipment moved away and no further assistance was required. It was a disappointment that as we got to the gate there were neither wing-walkers nor marshalls to guide us to parking which left us sitting at the apron 5-10 minutes even though company was fully aware we were coming back. In the end; another aircraft was assigned to us to perform an uneventful flight which resulted overall in a delay. As far as crewmembers knowledge there was no aircraft damage and no passenger's injured/requiring medical assistance.

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Original NASA ASRS Text

Title: A320 Captain reported the purser advised that there was a thick layer of light-gray smoke in passenger cabin and a strong hydraulic-like odor.

Narrative: After takeoff and climbing through 3000ft; purser called to the cockpit warning us that there was a thick layer of light-gray smoke in the mid-aft passenger cabin and a strong hydraulic-like odor (apparently it started when selecting landing gear up); which caused dizziness; sore throat and eye burn to many crewmembers and a few passengers. Both pilots immediately donned the oxygen masks as a precaution should smoke enter the cockpit.'Immediate actions' from the 'Smoke/Fumes/Avionics Smoke' QRH procedure were performed; which led to total smoke dissipation in only a minute. While the situation was under control and cabin crew confirmed no more smoke coming out (but still a strong; harmful odor/fumes); since it was a red-eye flight with few available airports for a further diversion and since smoke source was not immediately obvious (cabin crew could not determine where it was coming from) flight crew decided NOT to declare an emergency but to declare 'PAN-PAN' urgency to return to [departure airport] for landing. Landing was performed safely on [the] runway; and the aircraft was stopped short of runway to verify once again with cabin crew if there had been any more smoke or if an emergency evacuation would be required; while emergency equipment stood at the other side of runway. After confirming everything was still under control and smoke didn't come back we advised ATC and were cleared to taxi to gate as emergency equipment moved away and no further assistance was required. It was a disappointment that as we got to the gate there were neither wing-walkers nor marshalls to guide us to parking which left us sitting at the apron 5-10 minutes even though company was fully aware we were coming back. In the end; another aircraft was assigned to us to perform an uneventful flight which resulted overall in a delay. As far as crewmembers knowledge there was no aircraft damage and no passenger's injured/requiring medical assistance.

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.