# SDR UIEA2015050600263

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: May 6, 2015
- Submitted: May 6, 2015
- Operation: Air carrier
- Aircraft: [N249BA](https://openairdocs.org/aircraft/N249BA), registered now
- Make and model: Boeing 747409
- Aircraft serial: 24309
- Aircraft time: 73,258 hours, 14,470 cycles
- System (JASC): [3610 · Pneumatic Distribution System](https://openairdocs.org/jasc/3610)
- Part: Unknown
- Condition: Malfunctioned
- Location: Bleed Air Sys
- Stage of operation: DE
- How discovered: O
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/UIEA2015050600263

## Discrepancy

AT TOP, FL 370 DUCT PRESS SUDLING DROP TO 7 PSI WHEN THROTTLES RETARTED TO IDLE.  CABIN ALTITUDE ROSE TO 9300 FT & STABILIZED.  WITHIN 5 - 10 SECONDS PRESSURIZATION OF CABIN BEGAN TO RETURN TO NORMAL, NO OTHER NON-NORMAL NOTED.  PERFORMED BITE TEST OF SYS, BITE TEST PASSED, NO FAULTS NOTED ON CMC IAW AMM 36-11-30.

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