# SDR CALA2025090108309

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 29, 2025
- Submitted: September 1, 2025
- Operation: Air carrier
- Aircraft: [N17356](https://openairdocs.org/aircraft/N17356), registered now
- Make and model: Boeing 737-8
- Registry model: [Boeing 737-8](https://openairdocs.org/model/boeing-737-8) (OpenAirDocs)
- Aircraft serial: 67625
- Aircraft time: 3,532 hours, 1,202 cycles
- System (JASC): [2120 · Air Distribution System](https://openairdocs.org/jasc/2120)
- Part: Filter
- Part number: S161N3001
- Part serial: NOSERIAL
- Condition: Dirty
- Location: Zone 100
- Stage of operation: TX
- How discovered: O
- Nature of condition: B
- Precautionary procedure: D
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/CALA2025090108309

## Discrepancy

UNKNOWN BURNING ODOR COMING FROM AIR VENT OVER FORWARD FA JUMPSEAT.   CHECKED CEILING AREA ABOVE ENTRY. NO ODORS PRESENT & NO ANOMALIES FOUND. OPS SAFETY VIDEO & CHANGED LIGHTING SCHEMES WHILE RUNNING PACKS & WITH RECIRC FANS ALONE. ALL OVENS & AFT CHILLER OPERATING. COULD NOT DUPLICATE ODOR. GAINED ACCESS TO MIX BAY. NO ODORS NOTED. DISCONNECTED & RECONNECTED RECIRC FANS. START, STOP & OPS SMOOTH. FILTERS HAVE DUST BUILD UP. NO ODORS NOTED IN AVIONICS BAY. VERIFIED ALL C/B'S CLOSED ON P91 & P92 PANELS. CHKD E11 & E6 RACK UNITS IN AFT CARGO BAY. NO ODORS NOTED. REPLACED BOTH LT & RT RECIRC FILTERS IAW AMM 21-25-01/401. NO FAILED UNITS OR SUSPECT ITEMS SHOWING ON CURRENT OR EXISTING FAULTS.   ACCOMPLISHED 10 MIN IDLE RUN BOTH ENGS WITH ALL BLEEDS & BOTH PACKS RUNNING IAW FIM 21-00 TASK 830, STEP Q. NO SUSPECT ODORS GENERATED THROUGHOUT CABIN.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.