# SDR AALA202009229018

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 17, 2020
- Submitted: September 23, 2020
- Operation: Air carrier
- Aircraft: [N916AN](https://openairdocs.org/aircraft/N916AN), registered now
- Make and model: Boeing 737823
- Aircraft serial: 29517
- Aircraft time: 61,912 hours, 25,177 cycles
- System (JASC): [3460 · Flight Management Computing Hardware System](https://openairdocs.org/jasc/3460)
- Part: Relay
- Part number: 172934001
- Condition: Defective
- Location: Flt Management
- Stage of operation: DE
- How discovered: O
- Nature of condition: O
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/AALA202009229018

## Discrepancy

AIRCRAFT WAS GROUNDED.  CMD A AP ON, CA F/O ON DURING DESCENT F/O AIRSPEED REF BUG INCREASED AND SEPARATED FROM CA STANDBY AIRSPEED INDICATIONS.  F/O`S INDICATION INCREASED TO VMO.  F/O`S AIR SPEED INDICATION RETURNED TO MATCH CAPATAIN`S STANDBY INDICATION WHEN VNAV PATH DISENGAGED BY SWITCHING TO LVL CHG.  REPLACED FLIGHT CONTROL COMPUTER A AND ACCOMPLISHED A SATISFACTORY OPERATIONAL CHECK, PER AMM 22-11-33 (AALA202008219017).  REPLACED FLIGHT MANAGEMENT CONTROL SYSTEM TRANSFER RELAYS R475 (AALA202009229018) AND R475 (AALA202009229019).  ACCOMPLISHED A SATISFACTORY OPERATIONAL CHECK, PER AMM 34-61-04.

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