# SDR DALA2026031801868

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: March 16, 2026
- Submitted: March 18, 2026
- Operation: Air carrier
- Aircraft: [N939DZ](https://openairdocs.org/aircraft/N939DZ), registered now
- Make and model: Boeing 737-9GPER
- Registry model: [Boeing 737-9GPER](https://openairdocs.org/model/boeing-737-9gper) (OpenAirDocs)
- Aircraft serial: 38720
- Aircraft time: 32,065 hours, 19,212 cycles
- System (JASC): [2150 · Cabin Cooling System](https://openairdocs.org/jasc/2150)
- Part: A/C Pack
- Condition: Faulted
- Location: Zone 100
- Stage of operation: DE
- How discovered: O
- Nature of condition: J
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/DALA2026031801868

## Discrepancy

DUE TO CAB ALT LIGHT ILLUMINATED ON DESCENT. AIRCRAFT WOULD NOT MAINTAIN CABIN PRESSURE. RIGHT PACK ON MEL.   REPLACED RIGHT PACK TCV FOR MEL. FAILED SINGLE PACK CONFIDENCE CHECK. FOUND MULTIPLE FUSELAGE DRAIN VALVES LEAKING. REPLACED 10 DRAIN VALVES. REPLACED LEFT AND RIGHT PACK BAY FLEX DUCTS AFT OF CONDITIONED AIR CHECK VALVES FOR LEAKING. LEFT AND RIGHT PACKS PASS SINGLE PACK CONFIDENCE CHECKS. AIRCRAFT OK FOR SERVICE.

---
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.