# SDR 2016F00172

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 23, 2016
- Submitted: August 24, 2016
- Operation: General aviation
- Make and model: Boeing 737-3Q8
- Registry model: [Boeing 737-3Q8](https://openairdocs.org/model/boeing-737-3q8) (OpenAirDocs)
- Aircraft serial: 26309
- System (JASC): [2131 · Cabin Pressure Controller](https://openairdocs.org/jasc/2131)
- Part: Control Unit
- Part number: 655281057
- Condition: Malfunctioned
- Location: Cabin Pressure
- Stage of operation: CL
- How discovered: O
- Nature of condition: J
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/2016F00172

## Discrepancy

CABIN ALTITUDE UNCONTROLABLE IN AUTO ALTITUDE, AND MANUAL. QRF FLIGHT RETURNING TO DEPARTURE.

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