Narrative:

During climb out we noticed an odor in the cockpit that seemed to be like dirty socks or wet carpet. We asked flight attendants if they could smell the same thing but they said no. The captain went to the back of the aircraft to check. He could not smell it in the back. When he returned we determined that the fumes were starting to have an effect on both of us. We began running the fumes and smoke check list. We decided to divert to ZZZ. We began using oxygen. We briefed cat 3 approach and ran over weight landing check list. By this time in my opinion we both were becoming more and more incapacitated. Both of us were having problems concentrating on the tasks at hand. We were given priority handling by ATC and landed the aircraft without further problems. Emergency equipment met the aircraft when we exited the runway. We were given instructions to taxi to the ramp. By this time it seemed that we were nearly unable to follow instructions; but managed the aircraft to a gate. Fire and rescue inspected the aircraft but didn't find anything wrong.

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Original NASA ASRS Text

Title: A319 flight crew reported fumes in the flight deck. After a short time they began to experience problems concentrating and the onset of incapacitation.

Narrative: During climb out we noticed an odor in the cockpit that seemed to be like dirty socks or wet carpet. We asked flight attendants if they could smell the same thing but they said no. The captain went to the back of the aircraft to check. He could not smell it in the back. When he returned we determined that the fumes were starting to have an effect on both of us. We began running the fumes and smoke check list. We decided to divert to ZZZ. We began using oxygen. We briefed cat 3 approach and ran over weight landing check list. By this time in my opinion we both were becoming more and more incapacitated. Both of us were having problems concentrating on the tasks at hand. We were given priority handling by ATC and landed the aircraft without further problems. Emergency equipment met the aircraft when we exited the runway. We were given instructions to taxi to the ramp. By this time it seemed that we were nearly unable to follow instructions; but managed the aircraft to a gate. Fire and rescue inspected the aircraft but didn't find anything wrong.

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.