# SDR CALA2026070617564

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 2, 2026
- Submitted: July 6, 2026
- Operation: Air carrier
- Aircraft: [N34137](https://openairdocs.org/aircraft/N34137), registered now
- Make and model: Boeing 757224
- Aircraft serial: 30229
- Aircraft time: 91,990 hours, 21,881 cycles
- System (JASC): [2120 · Air Distribution System](https://openairdocs.org/jasc/2120)
- Part: Unknown
- Condition: Odor
- 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/CALA2026070617564

## Discrepancy

AFTER STARTING APU WE SMELL BURNED RUBBER SMEL IT GOES AWAY AND CYCLES BACK ABOUT EACH MINUTE. PERFORMED OPS TEST OF THE LH & RH AIR-CONDITIONING PACK.  CYCLED BETWEEN FULL HOT AND FULL COLD TEMP SETTINGS.  WENT THROUGH THE CABIN AND FLIGHT DECK TO SEE IF SMELL COULD BE DUPLICATED. WAS NOT ABLE TO DUPLICATE WRITE UP.  OPS CHECKED GOOD REF AMM TASK 21-51-03-404-018.  OPENED LH & RH AC BAYS AND PERFORMED A VISUAL INSPECTION, NO DEFECTS NOTED.

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