Narrative:

I was PF (pilot flying) started descent in ZZZ; captain asked me if I smelled a dirty sock smell. I said that I did. Although it wasn't real strong at first. Captain called the fas to ask them if they smelled anything. I was on ATC; so I didn't hear conversation with fas. Things were starting to get busy as we were on the arrival. We donned our oxygen masks when we thought that the odor had become more noticeable. Captain was running QRH and sending ACARS messages to company maintenance and dispatch dispatcher. [Notified ATC]. We made a normal approach and landed; taxied up but short of our gate. Then finally we were marshaled into the gate after a long wait. With the information the dispatcher had (fumes dirty socks smell) we should have been allowed to proceed straight to the gate. The captain and I both opened our windows in the rain to get fresh air into the aircraft as the smell was very strong by this point.cause: I believe it was oil aerosol from the engine into the packs.

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Original NASA ASRS Text

Title: A319 First Officer reported a 'dirty socks' smell in cockpit which steadily intensified and resulting into an uneventful landing.

Narrative: I was PF (Pilot Flying) started descent in ZZZ; Captain asked me if I smelled a dirty sock smell. I said that I did. Although it wasn't real strong at first. Captain called the FAs to ask them if they smelled anything. I was on ATC; so I didn't hear conversation with FAs. Things were starting to get busy as we were on the arrival. We donned our Oxygen masks when we thought that the odor had become more noticeable. Captain was running QRH and sending ACARS messages to Company Maintenance and Dispatch Dispatcher. [Notified ATC]. We made a normal approach and landed; taxied up but short of our gate. Then finally we were marshaled into the gate after a long wait. With the information the Dispatcher had (fumes dirty socks smell) we should have been allowed to proceed straight to the gate. The Captain and I both opened our windows in the rain to get fresh air into the aircraft as the smell was very strong by this point.Cause: I believe it was oil aerosol from the engine into the packs.

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.