# SDR CALA2026092319686

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: September 21, 2026
- Submitted: September 23, 2026
- Operation: Air carrier
- Aircraft: [N37253](https://openairdocs.org/aircraft/N37253), registered now
- Make and model: Boeing 737824
- Aircraft serial: 30584
- Aircraft time: 78,446 hours, 29,413 cycles
- System (JASC): [2120 · Air Distribution System](https://openairdocs.org/jasc/2120)
- Part: Air Filter
- Part number: 21FA407G
- Condition: Abnormal
- Location: Zone 100
- Stage of operation: NR
- How discovered: O
- Nature of condition: B
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/CALA2026092319686

## Discrepancy

SEC ENG START AND BUS XFER WHITE SMOKE ACRID SMELL ON FO SIDE VE NT UNDER WINDOW T/S AS PER AMM: 05-51-26-800-C1, STEP C: INITIAL INSP & OPS CHECKS AND DETAILED INSP & OPS CHECKS. LOAD SHED TEST OPS OK. COULD NOT DUPLICATE FAULT. NO EVIDENCE OF SMOKE IN CABIN OR COCKPIT IAW AMM.  REF: STEP E DISPOSITION OF EVENT. ACCOMPLISHED REPLACEMENT OF BOTH RECIR. FILTERS IAW AMM 21-25-01-000-801. PERFORMED OPS TEST IAW 710-802-002. OPS CHKD GOOD. OK FOR SERVICE.

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