Narrative:

I smelled smoke during cruise and inquired with the lead F/a (flight attendant) about checking to see if a passenger was smoking in one of the lavs. Just as I began this conversation; smoke began pouring into the cockpit. We donned our masks; [advised ATC] and requested priority handling to the nearest suitable airport. I executed an [expedited] descent and turned toward ZZZ. I made a PA and told the lead F/a what was happening. She confirmed smoke in the cabin as well. We had no ECAM (electronic aircraft centralized monitoring) indication of any faults. As the first officer (first officer) was re-programming the mcdu; I began scrolling through the system pages and looking for tripped circuit breakers. I found no abnormal indications. At about 15;000 ft.; the smoke dissipated slightly. It returned again at about 12;000 ft.; and I decided to try turning off the packs. At that point we got our first ECAM indications. The first was related to pack flow on both packs (due to turning them off) and the second was for a faulty pack regulator valve on pack 1. This turned out to be the cause of the event. The smoke cleared and we landed without further incident. [Maintenance] deferred pack 1 and we continued to [our destination] a few hours later. Some smoke events are pack related. This turned out to be the case for us.

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Original NASA ASRS Text

Title: The flight crew of an Airbus A319 detected smoke in both the cockpit and cabin. A descent was immediately initiated and a diversion to a suitable airfield was successfully accomplished. Troubleshooting revealed that a faulty air conditioning pack was the source of the smoke.

Narrative: I smelled smoke during cruise and inquired with the lead F/A (Flight Attendant) about checking to see if a passenger was smoking in one of the lavs. Just as I began this conversation; smoke began pouring into the cockpit. We donned our masks; [advised ATC] and requested priority handling to the nearest suitable airport. I executed an [expedited] descent and turned toward ZZZ. I made a PA and told the lead F/A what was happening. She confirmed smoke in the cabin as well. We had no ECAM (Electronic Aircraft Centralized Monitoring) indication of any faults. As the F/O (First Officer) was re-programming the MCDU; I began scrolling through the system pages and looking for tripped circuit breakers. I found no abnormal indications. At about 15;000 ft.; the smoke dissipated slightly. It returned again at about 12;000 ft.; and I decided to try turning off the packs. At that point we got our first ECAM indications. The first was related to pack flow on both packs (due to turning them off) and the second was for a faulty pack regulator valve on pack 1. This turned out to be the cause of the event. The smoke cleared and we landed without further incident. [Maintenance] deferred pack 1 and we continued to [our destination] a few hours later. Some smoke events are pack related. This turned out to be the case for us.

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.