# SDR ASAA2023060343448

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: June 3, 2023
- Submitted: June 5, 2023
- Operation: Air carrier
- Aircraft: [N407AS](https://openairdocs.org/aircraft/N407AS), registered now
- Make and model: Boeing 737-900ER
- Registry model: [Boeing 737-900ER](https://openairdocs.org/model/boeing-737-900er) (OpenAirDocs)
- Aircraft serial: 41731
- Aircraft time: 39,609 hours, 12,381 cycles
- System (JASC): [3610 · Pneumatic Distribution System](https://openairdocs.org/jasc/3610)
- Part: Regulator
- Part number: 1074926
- Part serial: 13348
- Condition: Faulty
- Location: #2 Engine
- Part time: 333 hours, 94 cycles
- Stage of operation: CR
- How discovered: V
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2023060343448

## Discrepancy

AT CRUISE ALT OF FL 330, DUCT SPLIT IS CONSISTENT AT 23 PSI. LEFT DUCT IS 40 PSI AND RIGHT PACK IS 17 PSI. OAT IS -50C AND ABOVE PRESSURES MEASURED AT 88.5% N1. GROUNDED - YES. ACCOMPLISHED HEALTH CHK TASK CARD NG-36WC-00002-2. REPLACED BLEED AIR REG REF B737-900 AMM 36-11-03. PERFORMED HIGH POWER RUN. R/H DUCT PRESS FAILED. 20%N1 L 20 PSI R 6 PSI, 60% N1 AND ABLOVE L-30 R-10.

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