# SDR FDEA202107041676

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 4, 2021
- Submitted: August 31, 2021
- Operation: Air carrier
- Aircraft: [N842FD](https://openairdocs.org/aircraft/N842FD), registered now
- Make and model: Boeing 777FHT
- Registry model: [Boeing 777FHT](https://openairdocs.org/model/boeing-777fht) (OpenAirDocs)
- Aircraft serial: 38969
- Aircraft time: 39,657 hours, 6,005 cycles
- System (JASC): [2121 · Air Distribution Fan](https://openairdocs.org/jasc/2121)
- Part: Fan
- Condition: Failed
- Location: Recirculation
- Stage of operation: NR
- How discovered: O
- Nature of condition: O, O, O
- Precautionary procedure: K, O, O, O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/FDEA202107041676

## Discrepancy

RH LOWER RECIRCULATION FAN IS CREATING VERY LOAD HUMING SOUND DURING   OPERATION.  FOUND R/H RECIRCULATION FAN INBOARD FILTER DEFORMED AND DRAWN DOWN INTO THE R/H RECIRCULATION FAN.   REMOVED AND REPLACED R/H RECIRCULATION FAN REF M.M. 21-25-07-4, OPS CK NORMAL, REMOVED AND REPLACED R/H RECIRCULATION FAN FILTERS REF M.M. 21-25-08-4. ALSO C/W L/H RECIRCULATION FAN FILTER REPLACEMENT REF B777 M.M. 21-25-08-4,  RECIRCULATION SYSTEM OPS CK NORMAL REF M.M. 21-25-00-5.

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