# SDR AALA202506259622

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: June 13, 2025
- Submitted: June 25, 2025
- Operation: Air carrier
- Aircraft: [N946NN](https://openairdocs.org/aircraft/N946NN), registered now
- Make and model: Boeing 737823
- Aircraft serial: 33234
- Aircraft time: 33,797 hours, 13,865 cycles
- System (JASC): [2210 · Autopilot System](https://openairdocs.org/jasc/2210)
- Part: Pressure Switch
- Condition: Failed
- Location: Zone 100
- Stage of operation: CL
- How discovered: O
- Nature of condition: B, F
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/AALA202506259622

## Discrepancy

AIRCRAFT WAS GROUNDED: AN EMERGENCY WAS DECLARED DUE TO: ON CLIMB OUT, PASSING 5000FT AND MAINTAINING 250KTS ENGAGED AUTOPILOT-B. A BUMP WAS FELT, AND THE AIRCRAFT WAS THEN UNABLE TO MAINTAIN PITCH AND AIRSPEED. AUTOPILOT WAS DISCONNECTED AND THE AIRCRAFT WAS HAND FLOWN. THEN AUTOPILOT-B WAS REENGAGED WITH THE SAME RESULT. STAB OUT OF TRIM LIGHT ILLUMINATED. AIRCRAFT AIR INTERRUPTED BACK TO AND LANDED SAFELY AT ORD. **SUPPLEMENTAL REPORT FOR (AALA202506178071): REMOVE AND REPLACE THE AUTOPILOT-B ACTUATOR UPPER ASSEMBLY (AALA202506178071), PER AMM 22-11-26. ADDITIONALLY, REPLACED THE HYDRAULIC PRESSURE SWITCH ON THE AUTOPILOT ACTUATOR-B (AALA202506259622), PER AMM 22-11-40. OPERATIONAL AND LEAK CHECK GIS OOD AT THIS TIME. NO ACTIVE FAULTS NOTED ON DFSC SYSTEM AT THIS TIME**(CLOSED).

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