# SDR ASAA1159620

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: May 7, 2011
- Submitted: May 11, 2011
- Operation: Air carrier
- Aircraft: [N569AS](https://openairdocs.org/aircraft/N569AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35184
- Aircraft time: 15,833 hours, 5,158 cycles
- System (JASC): [2210 · Autopilot System](https://openairdocs.org/jasc/2210)
- Part: Panel
- Part number: 8221567102
- Part serial: 14JJD
- Condition: Failed
- Location: Cockpit
- Part time: 26,101 hours, 10,130 cycles
- 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/ASAA1159620

## Discrepancy

AT TOP OF DESCENT (FL360) WHEN WE SET 12,000 FT IN ALTITUDE ALERTED FOR ATC RESTRICTION ALTITUDE ALERTER RESET TO 50,000 FT & ALTITUDE DEVIATION TONE SOUNDED.  ALTITUDE ALERTER WOULD NOT RESPOND TO INPUT & ALTITUDE DEVIATIION TONE SOUNDED CONTINUOUSLY TO TOUCHDOWN.  VERTICAL FLIGHT MODES UNRELIABLE.  REPLACED MCP PER AMM 22 11 34.  ACCOMPLISHED DFCS ADJUST/TEST PER AMM REF 22 11 00, OPS CHECK NORMAL.

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