# SDR ASAA2021061935143

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: June 19, 2021
- Submitted: June 30, 2021
- Operation: Air carrier
- Aircraft: [N566AS](https://openairdocs.org/aircraft/N566AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35182
- Aircraft time: 53,433 hours, 15,786 cycles
- System (JASC): [2210 · Autopilot System](https://openairdocs.org/jasc/2210)
- Part: Control Panel
- Condition: No Test
- Location: V/S Library
- Stage of operation: DE
- How discovered: O
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2021061935143

## Discrepancy

ON DESCENT VERTICAL SPEED WAS NOT SELECTABLE WOULD DEFAULT TO CURRENT DESCENT RATE AND WAS NOT CONTROLLABLE. GROUNDED - YES. MCP FAILED V/S LIBRARY TEST. REMOVED AND REPLACED MCP REF B737-800 AMM 22-11-34. OPS CHECK GOOD.

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