# SDR AALA201709069034

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: September 3, 2017
- Submitted: September 7, 2017
- Operation: Air carrier
- Aircraft: [N921NN](https://openairdocs.org/aircraft/N921NN), registered now
- Make and model: Boeing 737823
- Aircraft serial: 33229
- Aircraft time: 14,360 hours, 5,791 cycles
- System (JASC): [2120 · Air Distribution System](https://openairdocs.org/jasc/2120)
- Part: Air Filter
- Part number: P199753
- Condition: Odor
- Location: Cabin
- Stage of operation: TX
- How discovered: O
- Nature of condition: B
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/AALA201709069034

## Discrepancy

AIRCRAFT WAS GROUNDED.  DIRTY SOCK SMELL NOTICED ON TAXI OUT WITH APU NOT IN USE, DURING INITIAL CLIMB, AT CRUISE AFTER TURNING ON ANTI-ICE, AND AFTER START OF DESCENT.  ACCOMPLISHED CABIN ODOR TROUBLESHOOTING PER MCM CARD 05-96-70, NO ODOR NOTED.  REMOVED AND REPLACED LEFT RECIRCULATION AIR FILTER PER AMM 21-25-01 AT MOC REQUEST.  OPERATIONAL CHECK GOOD.

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